Method and system for shape-memory alloy wire control

Abstract

To provide a method and system for shape-memory alloy wire control.SOLUTION: The present invention defines a method for controlling an infusion pump by using a shape-memory alloy wire actuator and also defines a device corresponding to the method. The method includes determining, before actuation, an on-time on the basis of a target volume pumped by a shape-memory alloy wire plunger and the temperature of a shape-memory alloy wire. This adjusts the on-time of the actuator on the basis of the temperature of the shape-memory alloy wire. According to a first implementation, a method for controlling a device which uses the shape-memory alloy wire is disclosed. The method includes: determining an on-time for the shape-memory alloy wire on the basis of a target volume pumped by a pump plunger; determining the temperature of the shape-memory alloy wire; and adjusting the on-time on the basis of the temperature of the shape-memory alloy wire.SELECTED DRAWING: Figure 134

Description

Technical Field

[0001] This application is a non-provisional patent application and claims priority from U.S. Provisional Patent Application No. 61 / 297,506 (entitled "Method and System for Temperature Compensation in a Medical Device", filed on January 22, 2010, Attorney Docket No. H84), which is hereby incorporated by reference in its entirety.

[0002] This application is also a partial continuation application of U.S. Patent Application No. 12 / 347,981 (entitled "Infusion Pump Assembly", filed on December 31, 2008, currently published as U.S. Patent Application Publication No. US-2009-0275896-A1 (published on November 5, 2009), Attorney Docket No. G77), which is hereby incorporated by reference in its entirety. This application also claims priority from the following U.S. provisional patent applications, all of which are hereby incorporated by reference in their entirety: U.S. Provisional Patent Application No. 61 / 018,054 (entitled "Patch Pump with Shape Memory Wire Pump Actuator", filed on December 31, 2007, Attorney Docket No. E87); U.S. Provisional Patent Application No. 61 / 018,042 (entitled "Patch Pump with External Infusion Set", filed on December 31, 2007, Attorney Docket No. E88); U.S. Provisional Patent Application No. 61 / 017,989 (entitled "Wearable Infusion Pump with Disposable Base", filed on December 31, 2007, Attorney Docket No. E89); U.S. Provisional Patent Application No. 61 / 018,002 (entitled "Patch Pump with Rotational Engagement Assembly", filed on December 31, 2007, Attorney Docket No. E90); U.S. Provisional Patent Application No. 61 / 018,339 (entitled "System and Method for Controlling a Shape-Memory Actuator", filed on December 31, 2007, Attorney Docket No. E91); U.S. Provisional Patent Application No. 61 / 023,645 (entitled "Infusion Pump with Bolus Button", filed on January 25, 2008, Attorney Docket No. F49); U.S. Provisional Patent Application No. 61 / 101,053 (entitled "Infusion Pump Assembly with a Switch Assembly", filed on September 29, 2008, Attorney Docket No. F73); U.S. Provisional Patent Application No. 61 / 101,077 (entitled "Infusion Pump Assembly with a Tubing Storage", filed on September 29, 2008, Attorney Docket No. F74); U.S. Provisional Patent Application No. 61 / 101,105 (entitled "Improved Infusion Pump Assembly", filed on September 29, 2008, Attorney Docket No. F75), and U.S. Provisional Patent Application No. 61 / 101,115 (entitled "Filling Apparatus and Methods for an Infusion Pump Assembly", filed on September 29, 2008, Attorney Docket No. G08).

[0003] U.S. Patent Application No. 12 / 347,981 is a partial continuation application of each of the following applications: U.S. Patent Application No. 11 / 704,899 (entitled "Fluid Delivery Systems and Method", filed on February 9, 2007, currently, U.S. Patent Application Publication No. US-2007-0228071-A1 (published on October 4, 2007), Attorney Docket No. E70); U.S. Patent Application No. 11 / 704,896 (titled "Pumping Fluid Delivery Systems and Methods Using Force Application Assembly", filed on February 9, 2007, currently published as U.S. Patent Application Publication No. US-2007-0219496-A1 (published on September 20, 2007), Attorney Docket No. 1062 / E71); U.S. Patent Application No. 11 / 704,886 (titled "Patch-Sized Fluid Delivery Systems and Methods", filed on February 9, 2007, currently published as U.S. Patent Application Publication No. US-2007-0219480-A1 (published on September 20, 2007), Attorney Docket No. 1062 / E72), and U.S. Patent Application No. 11 / 704,897 (titled "Adhesive and Peripheral Systems and Methods for Medical Devices ", filed on February 9, 2007, currently published as U.S. Patent Application Publication No. US-2007-0219597-A1 (published on September 20, 2007), Attorney Docket No. 1062 / E73), all of which claim priority from the following U.S. Provisional Patent Applications, and all of which are hereby incorporated by reference in their entirety: U.S. Provisional Patent Application No. 60 / 772,313 (titled "Portable Injection System", filed on February 9, 2006, Attorney Docket No. 1062 / E42), U.S. Provisional Patent Application No. 60 / 789,243 / (titled "Method of Volume Measurement for Flow Control", filed on April 5, 2006, Attorney Docket No. 1062 / E53), and U.S. Provisional Patent Application No. 60 / 793,188 (titled "Portable Injection and Adhesive System", filed on April 19, 2006, Attorney Docket No. 1062 / E46), all of which are hereby incorporated by reference in their entirety.

[0004] U.S. Patent Application No. 11 / 704,899 (titled "Fluid Delivery Systems and Method", filed on October 4, 2007, currently published as U.S. Patent Application Publication No. US-2007-0228071-A1, Attorney Docket No. E70), U.S. Patent Application No. 12 / 347,981 (titled "Pumping Fluid Delivery Systems and Methods Using Force Application Assembly", filed on February 9, 2007, currently published as U.S. Patent Application Publication No. US-2007-0219496-A1 (published on September 20, 2007), Attorney Docket No. 1062 / E71), U.S. Patent Application No. 11 / 704,886 (titled "Patch-Sized Fluid Delivery Systems and Methods", filed on February 9, 2007, currently published as U.S. Patent Application Publication No. US-2007-0219480-A1 (published on September 20, 2007), Attorney Docket No. 1062 / E72), and U.S. Patent Application No. 11 / 704,897 (titled "Adhesive and Peripheral Systems and Methods for Medical Devices", filed on February 9, 2007, currently published as U.S. Patent Application Publication No. US-2007-0219597-A1 (published on September 20, 2007), Attorney Docket No. 1062 / E73) are all related to one another and Also related to U.S. Patent Application No. 60 / 889,007 (titled "Two-Stage Transcutaneous Inserter", filed on February 9, 2007, Attorney Docket No. 1062 / E74), which is incorporated herein by reference in its entirety.

[0005] (Field of the Invention) This application generally relates to fluid delivery systems, and more specifically, to infusion pump assemblies. [Background Art]

[0006] Many potentially valuable drugs or compounds containing biological agents are not orally effective due to poor absorption, poor liver metabolism, or other pharmacokinetic factors. In addition, some therapeutic compounds can be absorbed orally but may need to be administered frequently, making it difficult for patients to maintain the desired schedule. In such cases, parenteral delivery is often employed or can be employed.

[0007] Effective parenteral routes for drug delivery such as subcutaneous injection, intramuscular injection, and intravenous (IV) administration, as well as other fluids and compounds, involve piercing the skin with a needle or stylet. Insulin is an example of a therapeutic fluid that is self-injected by millions of diabetics. Users of parenteral delivery drugs can benefit from wearable devices that automatically deliver the required drug / compound over a period of time.

[0008] To achieve this goal, efforts have been made to design portable and wearable devices for the controlled release of therapeutic agents. Such devices are known to have a reservoir such as a cartridge, syringe, or bag and to be electronically controlled. These devices have a number of drawbacks, including a malfunction rate. Reducing the size, weight, and cost of these devices is also an ongoing challenge. In addition, these devices are often applied to the skin, presenting the challenge of frequent repositioning for application. SUMMARY OF THE INVENTION MEANS FOR SOLVING THE PROBLEM

[0009] According to a first implementation, a method for controlling a device using a shape memory alloy wire is disclosed. The method includes determining an on-time for the shape memory alloy wire based on a target volume pumped by a pump plunger, determining a temperature of the shape memory alloy wire, and adjusting the on-time based on the temperature of the shape memory alloy wire.

[0010] Some embodiments of this implementation include one or more of the following. The method further includes actuating a shape memory alloy wire to effect pumping a volume of fluid from a reservoir to a capacitive sensor chamber by a pump plunger, measuring the volume of the fluid being pumped using a capacitive sensor assembly, and determining a difference between a target volume and the volume of the fluid being pumped. The method further includes updating an on-time when the volume of the fluid being pumped exceeds or falls short of the target volume. The step of determining the temperature of the shape memory alloy wire further includes determining an elapsed time since actuation of the shape memory alloy and determining a predicted temperature of the shape memory alloy wire using the elapsed time.

[0011] According to another implementation, a method for controlling a device using a shape memory alloy wire is disclosed. The method includes determining an on-time for the shape memory alloy wire, determining the temperature of the shape memory alloy wire, and adjusting the on-time based on the temperature of the shape memory alloy wire.

[0012] In some embodiments of this implementation, the step of determining the temperature of the shape memory alloy wire further includes determining an elapsed time since actuation of the shape memory alloy and determining a predicted temperature of the shape memory alloy wire using the elapsed time.

[0013] According to another implementation, a shape memory alloy wire actuation system is disclosed. The system includes at least one shape memory alloy wire, a valve member connected to the at least one shape memory alloy wire, wherein the shape memory alloy wire, when actuated, actuates the valve member, a controller for controlling the on-time of the at least one shape memory alloy wire, and a temperature sensor for determining the temperature of the shape memory alloy wire. In this system, the controller determines the on-time based on the temperature of the shape memory alloy wire prior to actuation.

[0014] Some embodiments of this implementation may include one or more of the following. The system further includes a reservoir upstream of the valve member, and the valve member controls the flow of fluid flowing out of the reservoir. The temperature sensor is a thermistor. The temperature sensor is positioned adjacent to the shape memory alloy wire. The system further includes a capacitance measurement assembly upstream of the valve member, the capacitance measurement assembly includes a capacitance sensor chamber, fluid from the reservoir flows into the capacitance sensor chamber, and the capacitance measurement assembly determines the capacitance of the fluid in the capacitance sensor chamber.

[0015] According to another implementation, a shape memory alloy wire pumping system is disclosed. The system includes a pump plunger that effects pumping of fluid from a reservoir, at least one shape memory alloy wire connected to the pump plunger that, when actuated, actuates the pump plunger, a controller for controlling the on-time of the at least one shape memory alloy wire, and a temperature sensor for determining the temperature of the shape memory alloy wire, and the controller determines the on-time based on the temperature of the shape memory alloy wire prior to actuation.

[0016] Some embodiments of this implementation of the system may include one or more of the following. In this system, further, the temperature sensor is a thermistor. The temperature sensor is positioned adjacent to the shape memory alloy wire. The system further includes a capacitance measurement assembly downstream of the pump plunger, the capacitance measurement assembly includes a capacitance sensor chamber, fluid from the reservoir flows into the capacitance sensor chamber, and the system includes a capacitance measurement assembly that determines the capacitance of the fluid in the capacitance sensor chamber.

[0017] According to a first implementation, a wearable infusion pump assembly includes a reservoir for receiving an injectable fluid and an external infusion set configured to deliver the injectable fluid to a user. The fluid delivery system is configured to deliver the injectable fluid from the reservoir to the external infusion set. The fluid delivery system includes a volume sensor assembly and a pump assembly for extracting a quantity of the injectable fluid from the reservoir and providing the quantity of the injectable fluid to the volume sensor assembly. The volume sensor assembly is configured to determine the volume of at least a portion of the quantity of the fluid. The fluid delivery system also includes at least one optical sensor assembly and a first valve assembly configured to selectively isolate the pump assembly from the reservoir. The fluid delivery system further includes a second valve assembly configured to selectively isolate the volume sensor assembly from the external infusion set.

[0018] One or more of the following features may be included. The wearable infusion pump assembly may also include a disposable housing assembly including the reservoir and a first portion of the fluid delivery system. The wearable infusion pump assembly may also include a reusable housing assembly including a second portion of the fluid delivery system. The first portion of the pump assembly may be positioned within the disposable housing assembly. The second portion of the pump assembly may be positioned within the reusable housing assembly. The first portion of the first valve assembly may be positioned within the disposable housing assembly. The second portion of the first valve assembly may be positioned within the reusable housing assembly. The first portion of the second valve assembly may be positioned within the disposable housing assembly. The second portion of the second valve assembly may be positioned within the reusable housing assembly.

[0019] The external infusion set may be a detachable external infusion set configured to releasably engage with the fluid delivery system.

[0020] The mounted injection pump assembly may further include at least one processor and a computer-readable medium coupled to the at least one processor. The computer-readable medium may include a plurality of instructions stored thereon. When executed by the at least one processor, the instructions may cause the at least one processor to perform operations including activating a first valve assembly to isolate the pump assembly from the reservoir. The computer-readable medium may also include instructions for activating the pump assembly to provide a volume of injectable fluid to a volume sensor assembly.

[0021] The fluid delivery system may include an actuator associated with the first valve assembly. Activating the first valve assembly may include energizing the actuator. The actuator may include a shape memory actuator. The fluid delivery system may include an actuator associated with the pump assembly.

[0022] Activating the pump assembly may include energizing the actuator. The fluid delivery system may also include a bell crank assembly for mechanically coupling the pump assembly to the actuator. The actuator may include a shape memory actuator.

[0023] The computer-readable medium may further include instructions for activating the volume sensor assembly to determine the volume of at least a portion of the volume of fluid provided from the pump assembly to the volume sensor assembly. The computer-readable medium may also include instructions for activating the second valve assembly to fluidly couple the volume sensor assembly to an external injection set.

[0024] The fluid delivery system may include an actuator associated with a second valve assembly, and activating the second valve assembly includes energizing the actuator. The fluid delivery system may also include a bell crank assembly for mechanically coupling the second valve assembly to the actuator. The actuator may include a shape memory actuator.

[0025] The fluid delivery system may further include a bracket assembly configured to maintain the second valve assembly in an activated state. The computer-readable medium may further include instructions for activating the bracket assembly to release the second valve assembly from the activated state. The step of activating the bracket assembly may include the step of energizing a bracket actuator associated with the bracket assembly. The bracket actuator may include a shape memory actuator. This specification provides, for example, the following items. (Item 1) A method for controlling a device using a shape memory alloy wire, comprising: determining an on-time for the shape memory alloy wire based on a target volume delivered by a pump plunger; determining a temperature of the shape memory alloy wire; adjusting the on-time based on the temperature of the shape memory alloy wire and including a method. (Item 2) operating the shape memory alloy wire by the pump plunger to effect delivery of a volume of fluid from a reservoir to a capacitive sensor chamber; measuring the volume of the delivered fluid using a capacitive sensor assembly; determining a difference between the target volume and the volume of the delivered fluid and further including the method according to item 1. (Item 3) The method according to item 2, further comprising updating the on-time when the volume of the fluid to be delivered is greater than or less than the target volume. (Item 4) Determining the temperature of the shape memory alloy wire comprises: determining the elapsed time since the activation of the shape memory alloy; and using the elapsed time to determine the predicted temperature of the shape memory alloy wire. The method according to item 1, further comprising the above steps. (Item 5) A method for controlling a device using a shape memory alloy wire, comprising: determining an on-time for the shape memory alloy wire; determining the temperature of the shape memory alloy wire; and adjusting the on-time based on the temperature of the shape memory alloy wire. The method includes the above steps. (Item 6) Determining the temperature of the shape memory alloy wire comprises: determining the elapsed time since the activation of the shape memory alloy; and using the elapsed time to determine the predicted temperature of the shape memory alloy wire. The method according to item 5, further comprising the above steps. (Item 7) A shape memory alloy wire actuating system, comprising: at least one shape memory alloy wire; a valve member connected to the at least one shape memory alloy wire, wherein the shape memory alloy wire actuates the valve member when activated; a controller for controlling the on-time of the at least one shape memory alloy wire; and a temperature sensor for determining the temperature of the shape memory alloy wire. The controller determines the on-time based on the temperature of the shape memory alloy wire before activation. (Item 8) The system according to item 7, further comprising a storage part upstream of the valve member, wherein the valve member controls the flow of fluid from the storage part to the outlet. (Item 9) The system according to item 7, wherein the temperature sensor is a thermistor. (Item 10) The system according to item 7, wherein the temperature sensor is located adjacent to the shape memory alloy wire. (Item 11) The system according to item 8, further comprising a volume measurement assembly upstream of the valve member, the volume measurement assembly comprising a volume sensor chamber, fluid from the storage part flowing into the volume sensor chamber, and the volume measurement assembly determining the volume of fluid in the volume sensor chamber. (Item 12) A shape memory alloy wire delivery system, a pump plunger that effects the delivery of fluid from a storage part, at least one shape memory alloy wire connected to the pump plunger, which, when actuated, actuates the pump plunger, a controller for controlling the on-time of the at least one shape memory alloy wire, a temperature sensor for determining the temperature of the shape memory alloy wire and comprising, wherein the controller determines the on-time based on the temperature of the shape memory alloy wire before actuation. (Item 13) The system according to item 12, wherein the temperature sensor is a thermistor. (Item 14) The system according to item 13, wherein the temperature sensor is located adjacent to the shape memory alloy wire. (Item 15) The system according to item 8 further comprises a volume measurement assembly downstream of the pump plunger, the volume measurement assembly comprising a volume sensor chamber, fluid from the reservoir flowing into the volume sensor chamber, and the volume measurement assembly determining the volume of fluid in the volume sensor chamber.

[0026] Details of one or more embodiments are described in the following accompanying drawings and description. Other features and advantages will be apparent from the description, drawings, and claims.

Brief Description of the Drawings

[0027]

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[0028] Like reference symbols in the various drawings indicate like elements.

[0029] Referring to FIGS. 1-3, the infusion pump assembly 100 may include a reusable housing assembly 102. The reusable housing assembly 102 may be constructed from any suitable material such as a rigid or stiff plastic that resists compression. For example, the use of durable materials and components can improve quality and reduce costs by providing a more long-lasting and durable reusable portion that provides excellent protection for the components disposed therein.

[0030] The reusable housing assembly 102 may include a mechanical control assembly 104 having a pump assembly 106 and at least one valve assembly 108. The reusable housing assembly 102 may also include an electrical control assembly 110 configured to provide one or more control signals to the mechanical control assembly 104 to achieve basal and / or bolus delivery of injectable fluid to the user. The disposable housing assembly 114 may include a valve assembly 108 configured to control the flow rate of injectable fluid through the fluid path. The reusable housing assembly 102 may also include a pump assembly 106 configured to deliver injectable fluid from the fluid path to the user.

[0031] The electrical control assembly 110 can monitor and control the amount of injectable fluid that has been delivered and / or is being delivered. For example, the electrical control assembly 110 can receive a signal from the volume sensor assembly 148, calculate the amount of injectable fluid that has just been dispensed, and determine whether sufficient injectable fluid has been dispensed based on the dosage required by the user. If sufficient injectable fluid has not been dispensed, the electrical control assembly 110 can determine that more injectable fluid should be delivered. The electrical control assembly 110 may provide an appropriate signal to the mechanical control assembly 104 so that additional required dosages can be delivered, or the electrical control assembly 110 can provide an appropriate signal to the mechanical control assembly 104 so that additional dosages can be dispensed along with the next dosage. Alternatively, if excessive injectable fluid has been dispensed, the electrical control assembly 110 can provide an appropriate signal to the mechanical control assembly 104 so that less injectable fluid can be dispensed in the next dosage.

[0032] The mechanical control assembly 104 can include at least one shape memory actuator 112. The pump assembly 106 and / or the valve assembly 108 of the mechanical control assembly 104 can be actuated by at least one shape memory actuator, such as the shape memory actuator 112 which can be a shape memory wire in the form of a wire or a spring. The shape memory actuator 112 is operably connected to an electrical control assembly 110 that can control the timing and the amount of heat and / or electrical energy used to operate the mechanical control assembly 104, and can be activated by the electrical control assembly 110. The shape memory actuator 112 can be, for example, a conductive shape memory alloy wire that changes shape with temperature. The temperature of the shape memory actuator 112 can be changed by a heater or, more conveniently, by the application of electrical energy. The shape memory actuator 112 can be a shape memory wire made of a nickel / titanium alloy such as NITINOL TM or FLEXINOL®.

[0033] The infusion pump assembly 100 can include a volume sensor assembly 148 configured to monitor the amount of fluid infused by the infusion pump assembly 100. For example, the volume sensor assembly 148 can employ, for example, acoustic volume sensing. Acoustic volume measurement techniques are the subject of U.S. Pat. Nos. 5,575,310 and 5,755,683, assigned to DEKA Products Limited Partnership, and U.S. Patent Application Publication Nos. US2007 / 0228071A1, US2007 / 0219496A1, US2007 / 0219480A1, US2007 / 0219597A1, which are hereby incorporated by reference in their entireties. Other alternative techniques for measuring flow rate can also be used, such as Doppler-based methods, the use of Hall effect sensors in combination with vanes or flapper valves, the use of strain beams (e.g., related to a flexible member covering a fluid reservoir to sense deflection of the flexible member), the use of capacitance sensing with plates, or time-of-flight thermal methods. One such alternative technique is disclosed in U.S. Patent Application No. 11 / 704,899, filed Feb. 9, 2007, entitled Fluid Delivery Systems and Methods, the disclosure of which is hereby incorporated by reference in its entirety. The infusion pump assembly 100 can be configured such that volume measurements generated by the volume sensor assembly 148 can be used through a feedback loop to control the amount of injectable fluid injected into a user.

[0034] The infusion pump assembly 100 may further include a disposable housing assembly 114. For example, the disposable housing assembly 114 may be configured for single use or for use over a specified period, such as three days or any other amount of time. The disposable housing assembly 114 may be configured such that any components within the infusion pump assembly 100 that contact the injectable fluid are disposed on and / or within the disposable housing assembly 114. For example, a fluid path or channel including a reservoir may be located within the disposable housing assembly 114 and may be configured for single use or for a specified number of uses prior to disposal. The disposable nature of the disposable housing assembly 114 may improve the hygiene of the infusion pump assembly 100.

[0035] Referring also to FIG. 4, the disposable housing assembly 114 may be configured to releasably engage a reusable housing assembly 102 and includes a cavity 116 having a reservoir 118 for receiving an injectable fluid (not shown), such as insulin. Such releasable engagement may be achieved, for example, by a screw-type, twist-lock, or compression fit configuration. The disposable housing assembly 114 and / or the reusable housing assembly 102 may include an alignment assembly configured to assist in aligning the disposable housing assembly 114 and the reusable housing assembly 102 for engagement in a particular orientation. Similarly, a base knob 120 and a top knob 122 may be used as indicators of alignment and complete engagement.

[0036] The cavity 116 is at least partially formed by and may be integral with the disposable housing assembly 114. The cavity 116 may include a membrane assembly 124 for at least partially defining a reservoir 118. The reservoir 118 may be further defined by the disposable housing assembly 114, for example, by a recess 126 formed in a base portion 128 of the disposable housing assembly 114. For example, the membrane assembly 124 may be disposed to cover the recess 126 and attached to the base portion 128, thereby forming the reservoir 118. The membrane assembly 124 may be attached to the base portion 128 by conventional means such as adhesion, heat fusion, and / or compression fitting so that a seal 130 is formed between the membrane assembly 124 and the base portion 128. The membrane assembly 124 may be flexible, and the space formed between the membrane assembly 124 and the recess 126 of the base portion 128 may define the reservoir 118. The reservoir 118 is non-pressurized and may be in fluid communication with a fluid path (not shown). The membrane assembly 124 may be at least partially foldable, and the cavity 116 may include a vent assembly, thereby advantageously preventing the accumulation of a vacuum in the reservoir 118 when an injectable fluid is delivered from the reservoir 118 to the fluid path. In a preferred embodiment, the membrane assembly 124 is fully foldable, thus allowing for the complete delivery of the injectable fluid. The cavity 116 may be configured to provide sufficient space to ensure that there is always some void space even when the reservoir 118 is filled with the injectable fluid.

[0037] The membranes and reservoirs described herein may be made from materials including, but not limited to, silicone, nitrile, and any other material having the desired elasticity and properties to function as described herein. Additionally, other structures may be able to achieve the same purpose.

[0038] The use of a partially collapsible non-pressurized reservoir can advantageously prevent the accumulation of air in the reservoir as the fluid in the reservoir is depleted. The accumulation of air in a vented reservoir can prevent the escape of fluid from the reservoir, particularly when the system is tilted such that an air pocket is interposed between the fluid contained in the reservoir and the reservoir's partition walls. Tilting of the system is expected during normal operation as a wearable device.

[0039] Reservoir 118 can be conveniently sized to carry a sufficient supply of insulin for delivery over one or more days. For example, reservoir 118 can carry from about 1.00 to 3.00 ml of insulin. A 3.00 ml insulin reservoir can correspond to a supply for about three days for approximately 90% of potential users. In other embodiments, reservoir 118 can be of any size or shape and can be adapted to carry any amount of insulin or other injectable fluid. In some embodiments, the size and shape of cavity 116 and reservoir 118 are related to the type of injectable fluid that cavity 116 and reservoir 118 are adapted to carry.

[0040] The disposable housing assembly 114 can include a support member 132 (FIG. 3) configured to prevent accidental compression of reservoir 118. Compression of reservoir 118 can force an unintended dose of injectable fluid through the fluid path to the user. In a preferred embodiment, the reusable housing assembly 102 and the disposable housing assembly 114 can be constructed of a rigid material that is not easily compressible. However, as an additional precaution, support member 132 can be included within disposable housing assembly 114 to prevent compression of injection pump assembly 100 and cavity 116 therein. Support member 132 can be a rigid protrusion from base portion 128. For example, support member 132 can be disposed within cavity 116 and can prevent compression of reservoir 118.

[0041] As discussed above, the cavity 116 can be configured to provide sufficient space to ensure that there is always some void space even when the reservoir 118 is filled with an injectable fluid. Thus, if the injection pump assembly 100 is accidentally compressed, the injectable fluid cannot be pushed through the cannula assembly 136 (e.g., as shown in FIG. 9).

[0042] The cavity 116 can include a septum assembly 146 (FIG. 3) configured to allow the reservoir 118 to be filled with an injectable fluid. The septum assembly 146 can be a conventional septum made of rubber or plastic and can have a one-way fluid valve configured to allow a user to fill the reservoir 118 from a syringe or other filling device. In some embodiments, the septum 146 can be located at the top of the membrane assembly 124. In these embodiments, the cavity 116 can include a support structure (e.g., the support member 132 in FIG. 3) for supporting the area around the back surface of the septum to maintain the integrity of the septum seal when a needle is introducing an injectable fluid into the cavity 116. The support structure can be configured to support the septum while still allowing the introduction of a needle for introducing an injectable fluid into the cavity 116.

[0043] The injection pump assembly 100 can, for example, project into the cavity 116 and can include an overfill prevention assembly (not shown) that can prevent overfilling of the reservoir 118, for example.

[0044] In some embodiments, the reservoir 118 can be configured to be filled multiple times. For example, the reservoir 118 can be refillable via the septum assembly 146. Since an injectable fluid can be dispensed to a user, the electronic control assembly 110 can monitor the liquid level of the injectable fluid in the reservoir 118. When the liquid level reaches a low point, the electronic control assembly 110 can provide a signal, such as a light or vibration, to the user indicating that the reservoir 118 needs to be refilled. A syringe or other filling device can be used to fill the reservoir 118 through the septum 146.

[0045] The reservoir 118 can be configured to be filled once. For example, a refill prevention assembly (not shown) can be utilized to prevent refilling of the reservoir 118 so that the disposable housing assembly 114 can be used only once. The refill prevention assembly (not shown) can be a mechanical device or an electromechanical device. For example, insertion of a syringe into the septum assembly 146 for filling the reservoir 118 can induce a shutter to cover and close the septum 146 after one filling, thus preventing further access to the septum 146. Similarly, a sensor may indicate to the electronic control assembly 110 that the reservoir 118 has been filled once, and after one filling, a shutter can be induced to cover and close the septum 146, thus preventing further access to the septum 146. Other means of preventing refilling may be utilized and are considered within the scope of the present disclosure.

[0046] As discussed above, the disposable housing assembly 114 can include a septum assembly 146 configured to allow the reservoir 118 to be filled with an insoluble fluid. The septum assembly 146 can be a conventional septum made of rubber or any other material that can function as a septum, or in other embodiments, the septum assembly 146 can be a one-way fluid valve of plastic or other materials, but is not limited thereto. In various embodiments, including the exemplary embodiment, the septum assembly 146 is configured to allow a user to fill the reservoir 118 from a syringe or other filling device. The disposable housing assembly 114 can include a septum access assembly configured to limit the number of times a user can refill the reservoir 118.

[0047] For example, referring also to FIGS. 5A - 5C, the septum access assembly 152 may include a shutter assembly 154 that can be carried in an "open" position by a tab assembly 156 configured to fit within a slot assembly 158. When the filling syringe 160 penetrates the septum 146, the shutter assembly 154 may be disposed downwardly, disengaging the tab assembly 156 from the slot assembly 158. Once disengaged, a spring assembly 162 may displace the shutter assembly 154 in the direction of arrow 164, rendering the septum 146 no longer accessible to the user.

[0048] Referring also to FIG. 6A, an alternative embodiment of a septum access assembly 166 is shown in an "open" position. Similar to the septum access assembly 152, the septum access assembly 166 includes a shutter assembly 168 and a spring assembly 170.

[0049] Referring also to FIG. 6B, an alternative embodiment of a septum access assembly 172 is shown in an "open" position where a tab 178 can engage a slot 180. Similar to the septum access assembly 166, the septum access assembly 172 includes a shutter assembly 174 and a spring assembly 176. Once the shutter assembly 172 moves to a "closed" position (e.g., preventing further access to the septum 146 by the user), the tab 178 can engage at least partially within a slot 180a. The engagement between the tab 178 and the slot 180a can lock the shutter assembly 172 in the "closed" position, preventing tampering or re - opening of the shutter assembly 172. A spring tab 182 of the shutter assembly 172 can bias the tab 178 to engage the slot 180a.

[0050] However, in various embodiments, the septum access assembly may not be actuated linearly. For example, referring also to FIGS. 7A-7B, an alternative embodiment of the septum access assembly 184 is shown that includes a shutter assembly 186 configured to pivot about an axis 188. When positioned in the open position (as shown in FIG. 7A), the septum 146 may be accessible via a passage 190 (in the shutter assembly 186) that is aligned, for example, with a passage 192 in the surface of the disposable housing assembly 114. However, similar to the septum access assemblies 166, 172, when the fill syringe 160 (see FIG. 6B) penetrates the septum 146, the shutter assembly 186 may be displaced in a clockwise direction and the passage 190 (in the shutter assembly 186) may become misaligned with, for example, the passage 192 in the surface of the disposable housing assembly 114, thus preventing access to the septum 146.

[0051] Referring also to FIGS. 8A-8B, an alternative embodiment of the septum access assembly 194 is shown. Similar to the septum access assemblies 166, 172, the septum access assembly 194 includes a shutter assembly 196 and a spring assembly 198 configured to bias the shutter assembly 196 in the direction of arrow 200. A fill assembly 202 may be used to fill the reservoir 118. The fill assembly 202 may include a shutter displacement assembly 204 configured to displace the shutter assembly 196 in the direction of arrow 206, which in turn aligns a passage 208 in the shutter assembly 196 with a passage 210 in the septum 146 and the septum access assembly 194, thus enabling the fill syringe assembly 212 to penetrate the septum 146 and the fill reservoir 118.

[0052] The infusion pump assembly 100 may include a hermetic assembly 150 (FIG. 3) configured to provide a seal between a reusable housing assembly 102 and a disposable housing assembly 114. For example, when the reusable housing assembly 102 and the disposable housing assembly 114 are engaged, such as by a rotary screw engagement, a twist-lock engagement, or a compression engagement, the reusable housing assembly 102 and the disposable housing assembly 114 may fit tightly and thus form a seal. In some embodiments, it may be desirable for the seal to be more secure. Accordingly, the hermetic assembly 150 may include an O-ring assembly (not shown). Alternatively, the hermetic assembly 150 may include an externally coated seal assembly (not shown). The use of an O-ring assembly or an externally coated seal assembly may provide a compressible rubber or plastic layer between the reusable housing assembly 102 and the disposable housing assembly 114 when engaged, and thus may make the seal more secure by preventing penetration by external fluids. In some cases, the O-ring assembly may prevent accidental disengagement. For example, the hermetic assembly 150 may be a watertight assembly and thus may allow the user to wear the infusion pump assembly 100 while swimming, bathing, or exercising.

[0053] Referring also to FIG. 9, the infusion pump assembly 100 may include an external infusion set 134 configured to deliver a fluid injectable by the user. The external infusion set 134 may be in fluid communication with the cavity 118, for example, via a fluid path. The external infusion set 134 may be disposed adjacent to the infusion pump assembly 100. Alternatively, the external infusion set 134 may be configured for application remotely from the infusion pump assembly 100, as discussed in more detail below. The external infusion set 134 may include a cannula assembly 136 that may include a needle or a disposable cannula 138, and a tubing assembly 140. The tubing assembly 140 may be in fluid communication with the reservoir 118 and the cannula assembly 138, for example, directly or through a cannula interface 142, through a fluid path.

[0054] The external infusion set 134 can be a tethered infusion set, as discussed above with respect to remote application from the infusion pump assembly 100. For example, the external infusion set 134 can be in fluid communication with the infusion pump assembly 100 via a tubing assembly 140 that can be any length (e.g., 3 to 18 inches) desired by the user. The infusion pump assembly 100 can be worn on the user's skin by use of an adhesive patch 144, although the length of the tubing assembly 140 can alternatively enable the user to wear the infusion pump assembly 100 in a pocket. This can be beneficial for users whose skin is prone to inflammation upon application of the adhesive patch 144. Similarly, wearing and / or securing the infusion pump assembly 100 in a pocket may be preferable for users engaged in physical activity.

[0055] In addition to / alternatively to the adhesive patch 144, a Velcro® system (e.g., a Velcro® system provided by Velcro® USA Inc. (Manchester, NH)) can be utilized to enable easy attachment / removal of the infusion pump assembly (e.g., infusion pump assembly 100) to / from the user. Thus, the adhesive patch 144 can be attached to the user's skin and can include an outward-facing hook or loop surface. Additionally, the lower surface of the disposable housing assembly 114 can include a complementary hook or loop surface. Depending on the separation resistance of the particular type of Velcro® system employed, it can be possible for the strength of the hook and loop connection to be stronger than the strength of the adhesive for skin connection. Thus, various hook and loop surface patterns can be utilized to adjust the strength of the hook and loop connection.

[0056] Referring also to FIGS. 10A - 10E, five examples of such hook and loop surface patterns are shown. For illustrative purposes, assume that the entire lower surface of the disposable housing assembly 114 is covered with a "loop" material. Thus, the strength of the hook and loop connection can be adjusted by varying the pattern (i.e., amount) of "hook" material present on the surface of the adhesive patch 144. Examples of such patterns can include, but are not limited to, a single outer circle 220 of "hook" material (as shown in FIG. 10A), multiple concentric circles 222, 224 of "hook" material (as shown in FIG. 10B), multiple radial spokes 226 of "hook" material (as shown in FIG. 10C), multiple radial spokes 228 combined with a single outer circle 230 of "hook" material (as shown in FIG. 10D), and multiple radial spokes 232 combined with multiple concentric circles 234, 236 of "hook" material (as shown in FIG. 10E).

[0057] In addition, referring also to FIG. 11A, in one exemplary embodiment of the injection pump assembly described above, the injection pump assembly 100' can be configured via a remote control assembly 300. In this particular embodiment, the injection pump assembly 100' can include a telemetry circuit (not shown) that enables communication (e.g., wired or wireless) between the injection pump assembly 100' and, for example, the remote control assembly 300, thus enabling the remote control assembly 300 to remotely control the injection pump assembly 100'. The remote control assembly 300 (which may similarly include a telemetry circuit (not shown) and be capable of communicating with the injection pump assembly 100') can include a display assembly 302 and an input assembly 304. The input assembly 304 can include a slider assembly 306 and switch assemblies 308, 310. In other embodiments, the input assembly can include a jog wheel, multiple switch assemblies, or the like.

[0058] The remote control assembly 300 can include the ability to pre-program basal rates, bolus alarms, delivery limits, and may enable a user to view history and establish user preferences. The remote control assembly 300 may also include a glucose snippet reader.

[0059] In use, the remote control assembly 300 can provide commands to the infusion pump assembly 100' via a wireless communication channel 312 established between the remote control assembly 300 and the infusion pump assembly 100'. Thus, a user can use the remote control assembly 300 to program / configure the infusion pump assembly 100'. Some or all of the communication between the remote control assembly 300 and the infusion pump assembly 100' can be encrypted to provide an enhanced level of security.

[0060] Communication between the remote control assembly 300 and the infusion pump assembly 100' can be achieved using a standard communication protocol. Further, communication between various components included within the infusion pump assemblies 100, 100' can be achieved using the same protocol. An example of such a communication protocol is the Packet Communication Gateway Protocol (PCGP) developed by DEKA Research & Development (Manchester, NH). As discussed above, the infusion pump assemblies 100, 100' can include an electrical control assembly 110 that can include one or more electrical components. For example, the electrical control assembly 110 can include a plurality of data processors (e.g., a supervisor processor and a command processor) and a wireless processor to enable the infusion pump assemblies 100, 100' to communicate with the remote control assembly 300. Further, the remote control assembly 300 may include one or more electrical components, examples of which can include, but are not limited to, a command processor and a wireless processor to enable the remote control assembly 300 to communicate with the infusion pump assemblies 100, 100'. A high-level diagram of an example of such a system is shown in FIG. 11B.

[0061] Each of these electrical components may be manufactured by different component providers and may thus utilize unique (i.e., one-of-a-kind) communication commands. Thus, efficient communication between such heterogeneous components can be achieved through the use of a standard communication protocol.

[0062] PCGP can be a flexible and extensible software module that can be used on processors within the infusion pump assemblies 100, 100' and the remote control assembly 300 to construct and send packets. PCGP may abstract various interfaces and provide a unified application programming interface (API) to various applications running on each processor. PCGP may also provide an adaptation interface to various drivers. For illustrative purposes only, PCGP may have the conceptual structure illustrated in FIG. 11C for a given processor.

[0063] PCGP can ensure data integrity by utilizing cyclic redundancy checks (CRC). PCGP can also provide a guaranteed delivery status. For example, all new messages should have a reply. If such a reply is not sent back in time, the message may time out and PCGP can generate a negative response reply message (i.e., NACK) to the application. Thus, the message reply protocol can inform the application whether the application should retry sending the message.

[0064] PCGP may also limit the number of in-flight messages from a given node, may be coupled with a flow control mechanism at the driver level to provide a deterministic approach to message delivery, and may give individual nodes different amounts of buffer without withdrawing packets. When the buffer runs out at a node, the driver can provide backpressure to other nodes and prevent the transmission of new messages.

[0065] PCGP may use a shared buffer pool strategy and avoid mutual exclusion to minimize data copying, which has a slight impact on the APIs used to send / receive messages to the application and may have a greater impact on the driver. PCGP may use a "bridge" base class that provides routing and buffer ownership. The main PCGP classes may be subclassed from the bridge base class. The driver may be derived from the bridge class, communicate with, or own the derived bridge class.

[0066] PCGP may be designed to operate in an embedded environment with or without an operating system by using semaphores to protect shared data so that some calls are reentrant and can operate on multiple threads. An exemplary embodiment of such an implementation is shown in FIG. 11D. PCGP may operate in the same way in both environments, but there may be versions of calls for specific processor types (e.g., ARM 9 / OS version). Thus, the functionality may be the same, but there may be an operating system abstraction layer with slightly different calls, for example, suitable for the ARM 9 Nucleus OS environment.

[0067] Referring also to FIG. 11E, PCGP may do the following. · Enable multiple send / reply calls to occur (on Pilot’s ARM 9 on multiple reentrant tasks). · Have multiple drivers that operate asynchronously for RX and TX on different interfaces. · Provide packet ordering for transmission / reception and a deterministic timeout for message transmission.

[0068] Each software object may request the buffer manager for the next buffer to use, and then may give that buffer to another object. The buffer may be automatically passed from one exclusive owner to another, and a queue may be automatically generated by ordering the buffers by sequence number. When the buffer is no longer in use, the buffer may be recycled (e.g., an object releases the buffer to the buffer manager to give itself the buffer or to reallocate it later). Thus, data generally does not need to be copied, and routing simply overwrites the buffer owner byte.

[0069] Such an implementation of PCGP may provide various benefits, examples of which may include, but are not limited to, the following. · Once a message is in the buffer, it can persist there until transferred or received by the application, so message withdrawal due to buffer lack may not be possible. · Since offsets are used to access the driver, PCGP, and the payload section of the buffer, data may not need to be copied. · The driver can exchange ownership of message data by overwriting one byte (i.e., the buffer ownership byte). · Mutual exclusion may not be necessary except for reentrant calls, since mutual exclusion may be required only when a single buffer owner may wish to use the buffer simultaneously or acquire a new sequence number. · There may be fewer rules for application writers to follow to implement a reliable system. · Since there is a set of calls provided to push / pull data from the driver out of the buffer management system, the driver may use an ISR / push / pull / and polled data model. · The driver does not have to perform copy, CRC, or any other checks, but since destination bytes and CRC as well as other checks may be performed later from the ISR hot path, the driver does not have to operate much beyond TX and RX. · Since the buffer manager may order accesses by sequence number, queue ordering may occur automatically. · Small code / variable footprint may be used, the hot path code may be small, and the overhead may be low.

[0070] As shown in Figure 11F, when a message needs to be sent, the PCGP may quickly construct a packet and insert it into the buffer management system. Once inside the buffer management system, the call to "packetProcessor" may apply protocol rules and provide the message to the driver / application.

[0071] To send a new message or send a reply, the PCGP may do the following. · Check the call arguments, for example, to confirm that the packet length is legal, the destination is correct, etc. · Avoid attempting to send a message on a downlink link, unless it is a wireless link, that can enable the PCGP to be used by the wireless processor to establish a link, pair, etc., and can notify the application when the PCGP is attempting to communicate on a non-functional link (instead of timing out). · Obtain the sequence number of a new message or use the existing sequence number of an existing message. · Construct a packet, copy the payload data and write it to the CRC, and the integrity of the packet may be protected by the CRC since this point. · As a reply or a new message, giving the message to the buffer manager and putting this buffer into the buffer manager determines whether it exceeds the maximum number of transmission messages in the standby state.

[0072] Referring also to FIGS. 11G - 11H, the PCGP can operate by performing all of the major operations in one thread so as to avoid mutual exclusion and to avoid performing a great deal of work in transmission / reply or driver calls. The "packetProcessor" call may need to apply protocol rules to reply, new transmission messages, and received messages. The reply message can simply be sent, but for new messages and received messages, there may be rules for sending the message. In each case, the software can loop while the correct type of message can apply the protocol rules until it becomes unable to process the packet.

[0073] The transmission of new messages may follow the following rules. · Only two messages can be the permitted "in - flight" on the network. · Sufficient data regarding the in - flight message can be stored to match responses and handle timeouts.

[0074] The reception of messages may follow the following rules. · Since a matching response may remove the "in - flight" information slot, a new packet can be sent. · A non - matching response can be withdrawn. · The new message can be for the protocol (for example, obtaining / deleting network statistics for this node). · A buffer may be given to the application to receive the message and callback can be used. · The buffer can be freed or remain owned by the application.

[0075] Therefore, the PCGP can be configured as follows. · The return function may copy the payload data out or may fully consume it before returning. · The return function may own a buffer and reference the buffer's payload by the buffer and payload address, and the message may be processed later. · The application may poll the PCGP system for received messages. · The application may use the return to set an event and then poll for received messages.

[0076] The communication system may have a limited number of buffers. When the buffers for the PCGP run out, the driver may stop receiving new packets, and the application may be informed that the application cannot send new packets. To avoid this and maintain optimal performance, the application may attempt one or more procedures, examples of which may include, but are not limited to, the following. a) The application should keep the PCGP up-to-date in a wireless state. Specifically, if the link goes down and the PCGP is unaware, the PCGP may receive new messages to send and place them in a queue (or may not optimally time out the messages), which may interfere with the transmit queue and delay the application from optimally using the link. b) The application should periodically call "decrement the timeout." Optimally, this is every 20 - 100 milliseconds as long as the processor is not idle. Generally, messages move quickly (a few milliseconds), slowly (a few seconds), or not at all. The timeout is an attempt to remove "in-flight" messages that should be withdrawn to free up buffers and bandwidth. Doing this too frequently may delay the time when new messages are sent or when the application places new messages in the queue. c) The application should ask the PCGP whether there is any work to be done that is pending before pausing. If not for the PCGP, the driver activity may start the system and thus the PCGP, and then until a new packet enters the system, the PCGP does not need a call to "packetProcessor" or "decrement the timeout". Failure to do this may cause messages that should have been successfully sent / transferred / received to be withdrawn due to the timeout state. d) The application should not hold received messages indefinitely. The message system depends on a quick response. If the application shares the PCGP buffer, holding the message means holding the PCGP buffer. The receiving node does not know whether the sending node has a timeout configured for low or high-speed wireless communication. This means that when a node receives a message, it should measure the high-speed timeout speed of the network. e) The application should frequently call "packetProcessor". The call may cause the application to send new messages queued, and can handle the receipt of new messages. The call may also cause the buffer to be reallocated, and if not called too frequently, it may delay message traffic.

[0077] As shown in FIG. 11I, at some point, the RX driver may be required to receive a message from the opposite side of the interface. To ensure that the message is not withdrawn, the RX driver may ask the buffer manager whether there is a buffer available for storing the new message. Then, the driver may request a buffer pointer and may start filling the buffer with the received data. When a complete message is received, the RX driver may call the function to send the packet. The routing function may inspect the destination byte in the packet header and may change the owner to another driver or application, or may detect that the packet is defective and may withdraw the packet by releasing the buffer.

[0078] The PCGP RX overhead may consist of asking for the next available buffer and calling the routing function. An example of the code to perform such functions is as follows. @ Receive request uint8 i=0, * p; if (Bridge::canReceiveFlowControl()) { p = Bridge::nextBufferRX(); while (not done) { p[i] = the next byte;} Bridge::route(p); } The driver may perform TX by asking the buffer manager for a pointer to the next buffer to be sent. Then, the TX driver may ask the opposite side of the interface whether it can receive the packet. If the opposite side rejects the packet, the TX driver may not need to do anything to the buffer because its state has not changed. Otherwise, the driver may send the packet and may recycle / release the buffer. An example of the code to perform such functions is as follows. uint8 * p = Bridge::nextBufferTX(); if (p != (uint8 * )0) { send the buffer p; Bridge::recycle(p); } To avoid transferring packets that have exceeded the maximum message system timeout, in order to obtain the next buffer, BufferManager::first(uint8 owner) can be called to scan the buffers to be freed. Thus, a complete TX buffer that does not wish to time out can be freed on the thread that owns the buffer. The bridge that is performing TX (i.e., while looking for the next TX buffer) can free all TX buffers that will expire before receiving the next TX buffer for processing.

[0079] As shown in FIGS. 11J-11L, during the buffer allocation process, buffers marked as available can be transferred to the driver to receive new packets or to the PCGP to receive a new payload for TX. The allocation from "available" may be done by the "packetProcessor" function. The number of transmissions and receptions during a "packetProcessor" call can determine how many LT_Driver_RX, GT_Driver_RX, and PCGP_Free buffers need to be allocated. The LT_Driver may represent a driver that handles addresses less than the node address. The GT_Driver may represent a driver that handles addresses greater than the node address.

[0080] When the driver receives a packet, the driver may place the data in the RX buffer to be passed to the router. The router may then reassign the buffer to PCGP_Receive or the TX (not shown) of another driver. If the buffer contains clearly invalid data, the buffer may transition to an available state.

[0081] After the router marks the buffer for TX, the driver may discover that the buffer is for TX and may send a message. After sending the message, if the driver is short of RX buffers, the buffer may immediately become an RX buffer, or the buffer may be freed for reallocation.

[0082] During a "packetProcessor" call, PCGP may process all buffers marked by the router as PCGP_Receive. At this point, since the data may be acted upon, CRC and other data items may be checked. If the data is corrupted, a statistical value may be incremented and the buffer may be freed. Otherwise, the buffer may be marked as being owned by the application. Buffers marked as being owned by the application may be recycled for use by RCGP or freed for reallocation by the buffer manager.

[0083] When an application wants to send a new message, it may be done in a re - entrant, understandable / mutually - exclusive manner. If a buffer can be allocated, the PCGP may mark the buffer as in use. Once marked as in use, since it is owned by the invocation of the send or reply function, none of the other threads calling this function should capture this buffer. The remaining process of error - checking and message creation may be done outside the isolation - race - condition mutual - exclusion protection code. The buffer may transition to an available state or become a valid, filled, CRC - checked buffer that can be passed to the router. These buffers need not be sent immediately and can be queued (assuming protocol rules allow) to send the message later. Reply messages may be sent with a higher priority than normal send messages and may be marked differently from new send messages since there may be no rules limiting how many / when they can be sent.

[0084] The PCGP is designed to work in conjunction with flow control. Since the buffer may be missing on the opposite side of the interface (which may cause backpressure on the sending node), flow control may negotiate the transfer of messages from one node to another so that the buffer is never withdrawn.

[0085] Flow control may be part of the shared - buffer format. The first two bytes may be reserved for the driver so that the driver never has to shift packet bytes. The two bytes may be used such that one byte is the DMA length - 1 and the second byte controls the flow of the message. These same two bytes may synchronize the bytes when the PCGP message is transmitted over RS232.

[0086] When a packet is "in - flight", the packet may be in the process of being sent by the driver, processed by its destination, or returned as a response while en route to its destination.

[0087] Typical delays are as follows.

[0088]

Table 1

[0089] PCGP may use two different times (set at initialization) for all timeouts, one for when the RF link is in high heartbeat mode and the other for when the RF link is in low speed mode. If a message is in flight and the link state changes from high to low speed, the timeout may be adjusted, and the difference between high and low speed can be added to the expiration counter for the packet. Neither additional transitions back and forth should affect the expiration time for the message.

[0090] There is a second timeout, which can be twice the length of the low-speed timeout, used to monitor buffer allocation within PCGP. Therefore, for example, if a message is "left behind" in the driver and not sent due to flow control or hardware damage, the buffer may be released by the buffer manager to withdraw the buffer. For "new" messages, this may mean that a reply has already been given to the application that the packet has already timed out and the message was not delivered. Since the driver polls the buffer manager for buffers that need to be sent, the buffer is released so that when the next obstacle is removed, a message that can be sent is passed to the driver. For reply messages, the reply may simply be withdrawn, and the sending node may time out.

[0091] The PCGP messaging system can pass messages containing header information and a payload. Outside of PCGP, the header can be a set of data items in the call signature. However, inside PCGP, there can be a byte layout that is easy for a consistent driver to use. The driver can insert bytes into the PCGP packet or in front of the PCGP packet as follows. · DE, CA: Synchronization bytes for use with RS232, nominal values of 0xDE, 0xCA or 0x5A, 0xA5. · LD: Driver DMA length byte, equal to the amount the driver is push-delivering in this DMA transfer, which is the total size excluding the size byte or synchronization bytes. · Cmd: Driver command and control byte used for flow control. · LP: PCGP packet length, always the total header + payload size in bytes + CRC size. LD = LP + 1. · Dst: Destination address. · Src: Source address. · Cmd: Command byte. · Scd: Subcommand byte. · AT: The application tag is defined by the application and has no importance to PCGP. This allows the application to attach additional information to the message, such as the thread from which the message originated. · SeqNum: A 32-bit sequence number is incremented by PCGP for each new message sent, without wraparound, serving as a token, and ensuring endianness is irrelevant. · CRC16: 16-bit CRC of the PCGP header and payload.

[0092] An example of a message with no payload and cmd = 1, subcmd = 2 is as follows. 0xDE, 0xCA, 0xC, 0x5, 0x14, 1, 2, 0, 0, 0, 0, 0x1, crchigh, crclow. 0x0D, cmd, 0xC, 0x5, 0x14, 1, 2, 0, 0, 0, 0, 0x1, crchigh, crclow. This methodology may have several advantages, examples of which may include, but are not limited to, the following. · Most of our hardware DMA engines may use the first byte to define how many additional bytes to move, thus, in this methodology, the driver and PCGP may share the buffer. · A byte may be provided immediately after the DMA length to pass flow control information between drivers. · Since the driver length and the "Cmd" byte may be outside the CRC region, they may be modified by the driver, may be owned by the driver transport mechanism, and the driver may be vigilant about invalid lengths. · There may be a separate PGCP packet length byte protected by CRC. Thus, the application may rely on its payload length being correct. · The endianness of the sequence number may be a byte pattern that can be made to match, which happens to also be a 32-bit integer, so there may be no relevance. · The sequence number may be four bytes aligned to the edge of the shared buffer pool length. · While debugging the message stream, the user may move the cable around, and there may be an optional RS232 synchronization byte so that both sides of the interface can resynchronize. · The application, driver, and PCGP may share the buffer and may free them by pointer.

[0093] PCGP may not be event-driven software design, but can be used in an event-driven architecture depending on how the subclasses are written. Data may be conceptually exchanged between classes (as shown in FIGS. 11M-11N).

[0094] Some event models in the driver may start the driver, may receive a message, and may pass the message through the bridge into the buffer manager that sends the message to the new owner of the new message (through the bridge to the driver or the PCGP).

[0095] The following summarizes some exemplary events.

[0096] [Table 2] The following exemplary embodiments show how the PCGP event model can interact with Nucleus such that, after decTimeout that generated all sent messages, replies, or NACKs, the PCGP task is started. class PcgpOS : public Pcgp { virtual void schedulePacketProcessor(void) { OS_EventGrp_Set(g_RCVEvGrps[EVG_RF_TASK].pEvgHandle, RfRadioTxEvent, OS_EV_OR_NO_CLEAR); } } The following is an event-based pseudo-code driver that illustrates how the driver events operate. If the Driver sub-classifies the Bridge and disables hasMessagesToSend and flowControlTurnedOff, and the TX and RX functions are not already operating, they are scheduled to operate. class SPI_Driver : public Bridge { virtual void hasMessagesToSend() { Trigger_ISR(TX_ISR, this); } virtual void flowControlTurnedOff() { Trigger_ISR(RX_ISR, this); } static void TX_RetryTimer() { Trigger_ISR(TX_ISR, this); } static void TX_ISR(Bridge * b) { DisableISRs(); do { uint8 *p = b->nextBufferTX(); if (p == null) break; if (b->_bufferManager->bufferTimedOut(p)==false) { if (OtherSideSPI_FlowControl() == false) { Trigger TX_RetryTimer in 20 msec. break; } send(p); } free(p); } while (true) ; EnableISRs(); } static void RX_ISR(Bridge *b) { DisableISRs(); do { uint8* p = b->nextBufferRX(); if (p == null) break; uint i; while (not done receiving) p[i++] = getChar(); b->route(p); } while (true); EnableISRs(); } } The following statistical values can be supported by the PCGP. · The number of packets sent · The number of packets received · CRC errors · Timeouts · Unavailable buffers (buffers exhausted) The PCGP can be designed to operate in multiple processing environments. Most parameters can be configured at runtime to facilitate testing and runtime fine-tuning of performance. Other parameters may be at compile time, for example, anything that modifies memory allocations that must be done statically at compile time.

[0097] The following can be a specification of the number of compile-time configurations that may vary the location where the PCGP is implemented. · Driver byte count: It can be two bytes reserved for the common buffer scheme for the driver, which can be a compile-time option to adapt to other drivers such as RF protocols. · Number of RX driver buffers: It can be tuned for how many buffers are good for that processor / traffic flow, etc. · Number of PCGP RX buffers: It can be tuned for how many buffers are good for that processor / traffic flow, etc. · Total number of buffers: It can be tuned for how many buffers should be in that processor.

[0098] CRC can be used to ensure data integrity. If the CRC is invalid, it may not be delivered to the application and CRC errors can be tracked. The message may ultimately time out and can be retried by the originator.

[0099] Similarly, if the messaging system notifies the application that a message has been delivered when it has not, this can be dangerous to the system. A no-op stop command is an example of such a command. This can be mitigated by the message request / action sequence that may be required by the application to change the therapy. The controller may receive an authentication command from the pump application and consider the delivered message.

[0100] DEKA may provide a reference method to interface the PCGP to the Nucleus OS system on the ARM 9 (as shown in Figure 11O).

[0101] As shown in Figure 11P, the pcgpOS.cpp file may create instances of PCGP node instances (Pcgp, Bridge, etc.) and provide a set of "C" linkable function calls through pcgpOS.h that provide a "C" language interface to the C++ code. This may simplify the fact that the "C" code is implicit as the object on which the action acts.

[0102] The following general rules may apply. · The PCGP may operate on all nodes. Any driver may support the general driver interface. · Race conditions are not allowed. · Half-duplex may be supported on the SPI port between the slave and master processors. · Data transfers may not be attempted to return success or failure / false. · Low overhead (wasted time, processing, bandwidth) may be required. ·It can support the CC2510 operating at the DMA (high-speed) SPI clock speed.

[0103] On the receiving side, if there is no empty buffer for placing the packet currently, SPI flow control can prevent data from being transmitted. This can be achieved by requesting permission to transmit and waiting for a response indicating that permission has been granted. Also, there may be a way to inform the other party that there is no currently empty buffer and that a transfer should be attempted later.

[0104] All transmissions can start with a length byte indicating the number of bytes to be transmitted, not including the length byte itself. Following the length can be a single byte indicating the command being transmitted.

[0105] The actual transmission of the packet may be, for the command byte, the packet length plus 1, followed by the command byte for the attached message, and finally the packet itself.

[0106] In addition to the command byte being transmitted, an additional hardware line called the flow control line can be added to the conventional four SPI signals. The purpose of this line is to enable the protocol to operate as quickly as possible without a preset delay. It also enables the slave processor to inform the master processor that there is a packet waiting to be transmitted, thus eliminating the need for the master processor to poll the slave processor about the status.

[0107] The following exemplary command values can be used.

[0108]

Table 3

[0109]

Table 4

[0110] The master processor may initiate retrieval by sending the slave processor an M_CTS command. This is repeated by sending the S_MSG_APPENDED command along with the packet itself until the slave processor responds. The flow control line may be deasserted after the packet has been sent. If, unexpectedly, the M_CTS command is received by the slave processor, the M_CTS command may be ignored.

[0111] As shown in FIG. 11R, when the master processor has a packet to send to the slave processor, the master processor may initiate transfer by sending an M_RTS command. Upon receiving the M_RTS command, if the slave processor currently has a pending transmit packet, the slave processor lowers the flow control line so that it can be reused as a transmit enable signal. The slave processor may then inform the master processor that it is in the process of preparing the SPI DMA to receive the packet, during which time the master processor may stop measuring the byte time on the bus, enabling the slave processor to finish preparing for reception.

[0112] Next, the slave processor may indicate that it is ready to receive all packets by raising the flow control line (which is being used as the CTS signal). Upon receiving the CTS signal, the master processor may subsequently transmit the M_MSG_APPENDED command along with the packet itself.

[0113] After the transfer is complete, the slave processor may lower the flow control line. If a packet was pending at the start of the transfer or if transmission occurred on the slave processor while a packet was being received, the slave processor may re-assert the flow control line indicating that there is a pending packet.

[0114] Referring again to FIG. 11A, the infusion pump assemblies 100, 100' may include a switch assembly 318 coupled to an electrical control assembly 110 (FIG. 3) that may enable a user (not shown) to perform at least one task and in some embodiments a plurality of tasks. One exemplary embodiment of such a task is the administration of a bolus dose of an injectable fluid (e.g., insulin) without using a display assembly. The remote control assembly 300 may enable a user to activate / deactivate / configure the infusion pump assemblies 100, 100' to administer a bolus dose of insulin.

[0115] Referring also to FIG. 12A, the slider assembly 306 can be configured to at least partially enable a user to manipulate menu-based information rendered on the display assembly 302. An example of the slider assembly 306 may include a capacitive slider assembly that can be implemented using a CY8C21434-24LFXI PSOC provided by Cypress Semiconductor (San Jose, California), the design of whose operation is described in the "CSD User Module" published by Cypress Semiconductor. For example, via the slider assembly 306, a user can slide a finger in the direction of arrow 314 to bring about a highlighted portion of the information contained within the main menu 350 (shown in FIG. 12A) that is rendered on the display assembly 302 and scrolls upward. Alternatively, the user can slide a finger in the direction of arrow 316 to bring about a highlighted portion of the information contained within the main menu 350 that is rendered on the display assembly 302 and scrolls downward.

[0116] The slider assembly 306 can be configured to vary, for example, the speed at which the highlighted portion of the main menu 350 scrolls "upward" or "downward" in response to the displacement of the user's finger relative to the origin 320. Thus, if the user wishes to scroll "upward" quickly, the user may position a finger near the top of the slider assembly 306. Similarly, if the user wishes to scroll "downward" quickly, the user may position a finger near the bottom of the slider assembly 306. Additionally, if the user wishes to scroll "upward" slowly, the user may position a finger slightly "upward" relative to the origin 320. Further, if the user wishes to scroll "downward" slowly, the user may position a finger slightly "downward" relative to the origin 320. Once an appropriate menu item is highlighted, the user can select the highlighted menu item via one or more switch assemblies 308, 310.

[0117] Referring also to FIGS. 12B - 12F, assume for illustrative purposes that the infusion pump assemblies 100, 100' are insulin pumps, and that when the switch assembly 318 is depressed by the user, a 0.20 unit bolus dose of insulin is administered. Thus, for example, the user may use the slider assembly 306 to highlight "Bolus" within the main menu 350 rendered on the display assembly 302. The user may then use the switch assembly 308 to select "Bolus". Once selected, processing logic (not shown) within the remote control assembly 300 may render a sub - menu 352 on the display assembly 302 (as shown in FIG. 12B).

[0118] The user may then use the slider assembly 306 to highlight "Manual Bolus" within the sub - menu 352 that may be selected using the switch assembly 308. Processing logic (not shown) within the remote control assembly 300 may then render a sub - menu 354 on the display assembly 302 (as shown in FIG. 12C).

[0119] The user may then use the switch assembly 306 to select "Bolus: 0.0 units" within the sub - menu 354 that may be selected using the switch assembly 308. Processing logic (not shown) within the remote control assembly 300 may then render a sub - menu 356 on the display assembly 302 (as shown in FIG. 12D).

[0120] The user may then use the slider assembly 306 to adjust the "Bolus" insulin amount to "0.20 units" that may be selected using the switch assembly 308. Processing logic (not shown) within the remote control assembly 300 may then render a sub - menu 358 on the display assembly 302 (as shown in FIG. 12E).

[0121] Next, user 14 may use slider assembly 306 to highlight "Confirm", which may be selected using switch assembly 308. Next, processing logic (not shown) within remote control assembly 300 may generate an appropriate signal that may be transmitted to the above-described telemetry circuit (not shown) included within remote control assembly 300. Next, a telemetry circuit (not shown) included within the remote control assembly may, whenever switch assembly 318 is depressed by the user, transmit an appropriate configuration command to configure injection pump assembly 100' such that an insulin bolus dose of 0.20 units is administered via wireless communication channel 312 established between remote control assembly 300 and injection pump assembly 100'.

[0122] Once the transmission of the appropriate command is successful, the processing logic (not shown) within remote control assembly 300 may once again render sub-menu 350 on display assembly 302 (as shown in FIG. 12F).

[0123] Specifically, once programmed via remote control assembly 300, the user may depress switch assembly 318 of injection pump assembly 100' to administer the above-described insulin bolus dose of 0.20 units. Via the above-described menu system included within remote control assembly 300, the user may specify the amount of insulin to be administered each time the user depresses switch assembly 318. This specific example designates that one depression of switch assembly 318 is equivalent to 0.20 units of insulin, but this is for illustrative purposes only and is not intended to be a limitation of the present disclosure as other values (e.g., 1.00 unit of insulin per depression) are equally applicable.

[0124] For illustrative purposes, assume that the user desires to administer a bolus dose of 2.00 units of insulin. To activate the bolus dose administration system described above, the user may need to hold down the switch assembly 318 for a defined period (e.g., 5 seconds), at which point the infusion pump assemblies 100, 100' may generate an audible signal indicating to the user that the infusion pump assemblies 100, 100' are ready to administer a bolus dose of insulin via the switch assembly 318. Thus, the user may depress the switch assembly 318 ten times (i.e., 2.00 units are ten 0.20 unit doses). After each depression of the switch assembly 318, the infusion pump assemblies 100, 100' may provide an audible response to the user via an internal speaker / sound generating device (not shown). Thus, the user may first depress the switch assembly 318, and the infusion pump assemblies 100, 100' may generate a confirmation beep in response, thus indicating to the user that the infusion pump assemblies 100, 100' have received a command for 0.20 units of insulin (in this specific example). Since the desired bolus dose is 2.00 units of insulin, the user may repeat this procedure nine more times to achieve a bolus dose of 2.00 units, and the infusion pump assemblies 100, 100' may generate a confirmation beep after each depression of the switch assembly 318.

[0125] In this specific example, the infusion pump assemblies 100, 100' are described as providing one beep sound each time the user presses the switch assembly 318, but this is for illustrative purposes only and not intended to be a limitation of the present disclosure. Specifically, the infusion pump assemblies 100, 100' can be configured to provide a single beep sound for each prescribed dose of insulin. As discussed above, one press of the switch assembly 318 can be equivalent to 0.20 units of insulin. Thus, the infusion pump assemblies 100, 100' can be configured to provide a single beep sound for each 0.10 units of insulin. Therefore, if the infusion pump assemblies 100, 100' are configured such that one press of the switch assembly 318 is equivalent to 0.20 units of insulin, each time the switch assembly 318 is pressed, the infusion pump assemblies 100, 100' can provide two beep sounds to the user (i.e., one for each 0.10 units of insulin).

[0126] Once the user presses the switch assembly 318 on the infusion pump assembly 100' a total of 10 times, the user may simply wait for the infusion pump assemblies 100, 100' to approve the receipt of an order to administer a 2.00 unit bolus dose of insulin (as opposed to the confirmation beep sound received with each press of the switch assembly 318). Once a prescribed period of time (e.g., 2 seconds) has elapsed, the infusion pump assemblies 100, 100' can provide an audible confirmation to the user regarding the unit dose being administered via the bolus insulin dose requested by the user. For example, if the infusion pump assemblies 100, 100' are programmed by the user such that one press of the switch assembly 318 is equivalent to 0.20 units of insulin (in this example), the infusion pump assemblies 100, 100' can emit 10 beep sounds (i.e., 2.00 units is 10 doses of 0.20 units).

[0127] When providing feedback to the user regarding the unit dose administered via the bolus insulin dose, the infusion pump assemblies 100, 100' may provide a multi-frequency audible confirmation. For example, continuing with the above example where 10 beep sounds are provided to the user, the infusion pump assemblies 100, 100' may group the beep sounds into groups of 5 (to facilitate easier aggregation by the user), and the beep sounds within each group of 5 may be rendered by the infusion pump assemblies 100, 100' such that each subsequent beep sound has a higher frequency than the preceding beep sound (similar to a musical scale). Thus, continuing with the above example, the infusion pump assemblies 100, 100' may render a beep sound at 1,000 Hz, followed by a beep sound at 1,100 Hz, followed by a beep sound at 1,200 Hz, followed by a beep sound at 1,300 Hz, followed by a beep sound at 1,400 Hz (thus completing a group of 5 beep sounds), followed by a short pause, then a beep sound at 1,000 Hz, followed by a beep sound at 1,100 Hz, followed by a beep sound at 1,200 Hz, followed by a beep sound at 1,300 Hz, followed by a beep sound at 1,400 Hz (thus completing a second group of 5 beep sounds). According to various additional / alternative embodiments, the multi-frequency audible confirmation may utilize various numbers of tones with increasing frequencies. For example, an embodiment may utilize 20 different tones with increasing frequencies. However, since the number of tones may vary depending on design criteria and user needs, the number of tones should not be construed as a limitation of the present disclosure.

[0128] Once the infusion pump assemblies 100, 100' have completed rendering the multi - frequency audible confirmation (i.e., the 10 beep sounds described above), the user may, within a specified period (e.g., 2 seconds), press the switch assembly 318 to provide a confirmation signal to the infusion pump assemblies 100, 100', indicating that the multi - frequency audible confirmation is accurate and represents the size of the bolus dose of insulin to be administered (i.e., 2.00 units). Upon receiving this confirmation signal, the infusion pump assemblies 100, 100' may render an audible sound of "confirmation received" and (in this particular embodiment) may achieve delivery of a 2.00 unit bolus dose of insulin. If the infusion pump assemblies 100, 100' do not receive the above - mentioned confirmation signal, the infusion pump assemblies 100, 100' may render an audible sound of "confirmation failed" and may not achieve delivery of the bolus dose of insulin. Thus, if the multi - frequency audible confirmation is not accurate / does not indicate the size of the bolus dose of insulin to be administered, the user may simply not provide the above - mentioned confirmation signal, thereby aborting delivery of the bolus dose of insulin.

[0129] As discussed above, in one exemplary embodiment of the infusion pump assembly described above, the infusion pump assembly 100' can be used to communicate with a remote control assembly 300. When such a remote control assembly 300 is utilized, the infusion pump assembly 100' and the remote control assembly 300 can periodically contact each other to ensure that the two devices are still communicating with each other. For example, the infusion pump assembly 100' can send a "ping" to the remote control assembly 300 to ensure that the remote control assembly 300 is present and operating. Further, the remote control assembly 300 can send a "ping" to the infusion pump assembly 100' to ensure that the infusion pump assembly 100' is still present and operating. If either the infusion pump assembly 100' or the remote control assembly 300 is unable to establish communication with the other assembly, the assembly that cannot establish communication can sound a "separation" alarm. For example, assume that the remote control assembly 300 is left in the user's car while the infusion pump assembly 100' is in the user's pocket. Thus, after a defined period, the infusion pump assembly 100' can begin to sound a "separation" alarm, indicating that it is unable to establish communication with the remote control assembly 300. Using a switch assembly 318, the user can approve / silence this "separation" alarm.

[0130] While the remote control assembly 300 is not communicating with the infusion pump assembly 100', the user can define and administer a bolus insulin dose via the switch assembly 318 of the infusion pump assembly 100'. Therefore, the infusion pump assembly 100' can store information regarding the administered bolus insulin dose in a log file (not shown) stored within the infusion pump assembly 100'. This log file (not shown) can be stored in a non-volatile memory (not shown) included within the infusion pump assembly 100'. When communication is re-established between the infusion pump assembly 100' and the remote control assembly 300, the infusion pump assembly 100' can provide the remote control assembly 300 with information regarding the administered bolus insulin dose stored in the log file (not shown) of the infusion pump assembly 100'.

[0131] Furthermore, if the user anticipates separating the remote control assembly 300 from the infusion pump assembly 100', the user can configure the infusion pump assembly 100' and the remote control assembly 300 to enter the "separation" mode (via the above menu system), thus eliminating the occurrence of the above "separation" alarm. However, when the devices resume communication with each other, they may continue to "ping" each other so that the infusion pump assembly 100' and the remote control assembly 300 can automatically exit the "separation" mode.

[0132] Furthermore, if the user anticipates traveling by aircraft, the user can configure the infusion pump assembly 100' and the remote control assembly 300 to enter the "aircraft" mode in which all data transmissions are temporarily halted for each of the infusion pump assembly 100' and the remote control assembly 300 (via the above menu system of the remote control assembly 300). During the "aircraft" mode, the infusion pump assembly 100' and the remote control assembly 300 may or may not continue to receive data.

[0133] The switch assembly 318 can be used to perform additional functions such as checking the battery life of the reusable housing assembly 102, pairing the reusable housing assembly 102 with the remote control assembly 300, and interrupting the bolus dose administration of the injectable fluid.

[0134] Step of checking battery life: The reusable housing assembly 102 may include a rechargeable battery assembly that can potentially power the infusion pump assemblies 100, 100' for about three days (when fully charged). Such a rechargeable battery assembly may have a predetermined number of usable hours, such as a number of years of usable life, or other predetermined length of usable time. However, the predetermined life may depend on many factors including, but not limited to, one or more of climate, daily use, and number of recharges. Whenever the reusable housing assembly 102 is disconnected from the disposable housing assembly 114, or whenever the switch assembly 318 is depressed for a specified period (e.g., more than 2 seconds), a battery check may be performed on the rechargeable battery assembly described above. If it is determined that the rechargeable battery assembly described above is charged above a desired threshold, the infusion pump assemblies 100, 100' may render a "battery okay" tone. Alternatively, if it is determined that the rechargeable battery assembly described above is charged below a desired threshold, the infusion pump assemblies 100, 100' may render a "low battery" tone. The infusion pump assemblies 100, 100' may include components and / or circuitry to determine whether the reusable housing assembly 102 is disconnected from the disposable housing assembly 114.

[0135] Pairing step: As discussed above, in one exemplary embodiment of the infusion pump assembly, the infusion pump assembly 100' can be used to communicate with the remote control assembly 300. A pairing process may be performed to achieve communication between the infusion pump assembly 100' and the remote control assembly 300. During such a pairing process, one or more infusion pump assemblies (e.g., infusion pump assembly 100') may be configured to communicate with the remote control assembly 300, and (conversely) the remote control assembly 300 may be configured to communicate with one or more infusion pump assemblies (e.g., infusion pump assembly 100'). Specifically, the serial number of the infusion pump assembly (e.g., infusion pump assembly 100') may be recorded in a pairing file (not shown) included within the remote control assembly 300, and the serial number of the remote control assembly 300 may be recorded in a pairing file (not shown) included within the infusion pump assembly (e.g., infusion pump assembly 100').

[0136] According to an embodiment, to achieve such a pairing procedure, the user may simultaneously press one or more switch assemblies on both the remote control assembly 300 and the infusion pump assembly 100'. For example, the user may simultaneously press the switch assembly 310 included within the remote control assembly 300 and the switch assembly 318 included within the infusion pump assembly 100' for a defined period of time, such as over 5 seconds. Once this defined period of time is reached, one or more of the remote control assembly 300 and the infusion pump assembly 100' may generate an audible signal indicating that the pairing procedure has been achieved.

[0137] According to another embodiment, prior to performing the pairing process, the user may disconnect the reusable housing assembly 102 from the disposable housing assembly 114. By requiring this initial step, further assurance is provided that the infusion pump assembly being worn by the user cannot be inadvertently paired with the remote control assembly.

[0138] Once disconnected, the user can enter the pairing mode via the input assembly 304 of the remote control assembly 300. For example, the user can enter the pairing mode on the remote control assembly 300 via the above menu system combined with, for example, the switch assembly 310. The user can be instructed on the display assembly 302 of the remote control assembly 300 to press and hold the switch assembly 318 on the infusion pump assembly 100'. In addition, the remote control assembly 304 may switch to a low power mode, for example, to avoid attempting to pair with a remote infusion pump assembly. The user may then press and hold the switch assembly 318 on the infusion pump assembly 100' so that the infusion pump assembly 100' enters the receiving mode and waits for a pairing command from the remote control assembly 300.

[0139] The remote control assembly 300 may then transmit a pairing request to the infusion pump assembly 100', which may be approved by the infusion pump assembly 100'. The infusion pump assembly 100' may perform a security check on the pairing request received from the remote control assembly 300, and (if the security check passes) the infusion pump assembly 100' may activate a pump pairing signal (i.e., enter the active pairing mode). The remote control assembly 300 may perform a security check on the approval received from the infusion pump assembly 100'.

[0140] The authorization received from the infusion pump assembly 100' may define the serial number of the infusion pump assembly 100', and the remote control assembly 300 may display that serial number on the display assembly 302 of the remote control assembly 300. The user may be asked if they wish to pair with the found pump. If the user declines, the pairing process may be interrupted. If the user consents to the pairing process, the remote control assembly 300 may instruct the user (via the display assembly 302) to press and hold the switch assembly 318 on the infusion pump assembly 100'.

[0141] Next, the user may press and hold the switch assembly 318 on the infusion pump assembly 100' and, for example, also press and hold the switch assembly 310 on the remote control assembly 300.

[0142] The remote control assembly 300 may confirm that the remote switch assembly 310 has been pressed (which may be reported to the infusion pump assembly 100'). The infusion pump assembly 100' may perform a security check on the confirmation received from the remote control assembly 300 to verify the integrity of the confirmation. If the integrity of the received confirmation is not proven, the pairing process is interrupted. If the integrity of the received confirmation is proven, any existing remote pairing configuration file is overwritten to reflect the newly paired remote control assembly 300, a pump pairing completion signal is activated, and the pairing process is complete.

[0143] In addition, the infusion pump assembly 100' can confirm that the switch assembly 318 has been pressed (which can be reported to the remote control assembly 300). The remote control assembly 300 can perform a security check on the confirmation received from the infusion pump assembly 100' to confirm the integrity of the confirmation. If the integrity of the received confirmation is not proven, the pairing process is interrupted. If the integrity of the received confirmation is proven, the pair list file in the remote control assembly 300 can be modified to add the infusion pump assembly 100'. Generally, while the remote control assembly 300 may be able to pair with multiple infusion pump assemblies, the infusion pump assembly 100' may only be able to pair with a single remote control assembly. A pairing completion signal may be activated to complete the pairing process.

[0144] When the pairing process is completed, one or more of the remote control assembly 300 and the infusion pump assembly 100' can generate an audible signal indicating that the above pairing procedure has been successfully achieved.

[0145] Step of interrupting the bolus dose: If the user wishes to discontinue, for example, the bolus dose of insulin being administered by the infusion pump assembly 100', the user can press the switch assembly 318 (shown in FIGS. 1 and 2, for example) for a defined period exceeding, for example, 5 seconds. Once this defined period is reached, the infusion pump assembly 100' can render an audible signal indicating that the above discontinuation procedure has been achieved.

[0146] The switch assembly 318 is shown as being positioned at the top of the infusion pump assemblies 100, 100', but this is for illustrative purposes only as other configurations are possible and is not intended to be a limitation of the present disclosure. For example, the switch assembly 318 can be positioned around the infusion pump assemblies 100, 100'.

[0147] Referring also to FIGS. 13 - 15, an injection pump assembly 400 of an alternative embodiment is shown. Similar to the pump assemblies 100, 100', the injection pump assembly 400 may include a reusable housing assembly 402 and a disposable housing assembly 404.

[0148] Similar to the reusable housing assembly 102, the reusable housing assembly 402 may include a mechanical control assembly (including at least one pump assembly and at least one valve assembly). The reusable housing assembly 402 may also include an electrical control assembly configured to provide control signals to the mechanical control assembly to achieve delivery of injectable fluid to the user. The valve assembly may be configured to control the flow rate of injectable fluid through the fluid path, and the pump assembly may be configured to deliver injectable fluid from the fluid path to the user.

[0149] Similar to the disposable housing assembly 114, the disposable housing assembly 404 may be configured for single use or for use over a specified period, such as, for example, three days or any other amount of time. The disposable housing assembly 404 may be configured such that any components within the injection pump assembly 400 that contact the injectable fluid are disposed on and / or inside the disposable housing assembly 404.

[0150] In a particular embodiment of this injection pump assembly, the injection pump assembly 400 may include a switch assembly 406 positioned around the injection pump assembly 400. For example, the switch assembly 406 may be positioned along the radial edge of the injection pump assembly 400, which may enable easier use by the user. The switch assembly 406 may be covered with a waterproof membrane configured to prevent ingress of water into the injection pump assembly 400. The reusable housing assembly 402 may include a main body 408 (housing the mechanical and electrical control assemblies described above) and a locking ring assembly 410 configured to rotate around the main body 408 in the direction of arrow 412.

[0151] Similar to the reusable housing assembly 102 and the disposable housing assembly 114, the reusable housing assembly 402 can be configured to releasably engage with the disposable housing assembly 404. Such a releasable engagement can be achieved, for example, by a screw-type, twist-lock, or compression fit configuration. In an embodiment where a twist-lock configuration is utilized, the user of the injection pump assembly 400 may first properly position the reusable housing assembly 402 relative to the disposable housing assembly 404, and then rotate the locking ring assembly 410 (in the direction of arrow 412) to releasably engage the reusable housing assembly 402 with the disposable housing assembly 404.

[0152] Through the use of the locking ring assembly 410, the reusable housing assembly 402 can be properly positioned relative to the disposable housing assembly 404 and then releasably engaged by rotating the locking ring assembly 410, thus eliminating the need to rotate the reusable housing assembly 402 relative to the disposable housing assembly 404. Accordingly, the reusable housing assembly 402 may be properly aligned with the disposable housing assembly 404 prior to engagement, and such alignment should not be disrupted during the engagement process. The locking ring assembly 410 may include a latching mechanism (not shown) that can prevent rotation of the locking ring assembly 410 until the reusable housing assembly 402 and the disposable housing assembly 404 are properly positioned relative to each other.

[0153] Referring also to FIGS. 16 - 18, an injection pump assembly 500 of an alternative embodiment is shown. Similar to the pump assemblies 100, 100', the injection pump assembly 500 may include a reusable housing assembly 502 and a disposable housing assembly 504.

[0154] Similar to the reusable housing assembly 402, the reusable housing assembly 502 may include a machine control assembly (including at least one pump assembly and at least one valve assembly). The reusable housing assembly 502 may also include an electrical control assembly configured to provide a control signal to the machine control assembly to achieve delivery of injectable fluid to a user. The valve assembly may be configured to control the flow rate of injectable fluid through the fluid path, and the pump assembly may be configured to deliver injectable fluid from the fluid path to the user.

[0155] Similar to the disposable housing assembly 404, the disposable housing assembly 504 may be configured for single use or for use over a specified period, such as, for example, three days or any other amount of time. The disposable housing assembly 504 may be configured such that any components within the injection pump assembly 500 that contact the injectable fluid are disposed on and / or inside the disposable housing assembly 504.

[0156] In certain embodiments of this infusion pump assembly, the infusion pump assembly 500 may include a switch assembly 506 positioned peripherally to the infusion pump assembly 500. For example, the switch assembly 506 may be positioned along the radial edge of the infusion pump assembly 500, which may enable easier use by the user. The switch assembly 506 may be covered with a waterproof membrane and / or an O-ring, or alternatively, other sealing mechanisms may be included over the handle 507 of the switch assembly 506 configured to prevent water infiltration into the infusion pump assembly 500. However, in some embodiments, the switch assembly 506 includes an externally coated rubber button and thus may provide functionality as a waterproof seal without using a waterproof membrane or an O-ring. However, in yet other embodiments, the externally coated rubber button may additionally include a waterproof membrane and / or an O-ring. The reusable housing assembly 502 may include a main body 508 (housing the mechanical and electrical control assemblies described above) and a locking ring assembly 510 configured to rotate around the main body 508 (in the direction of arrow 512).

[0157] Similar to the reusable housing assembly 402 and the disposable housing assembly 404, the reusable housing assembly 502 may be configured to releasably engage with the disposable housing assembly 504. Such releasable engagement may be achieved, for example, by a screw-type, twist-lock, or compression fit configuration. In embodiments where a twist-lock configuration is utilized, the user of the infusion pump assembly 500 may first properly position the reusable housing assembly 502 relative to the disposable housing assembly 504 and then rotate the locking ring assembly 510 (in the direction of arrow 512) to releasably engage the reusable housing assembly 502 with the disposable housing assembly 404.

[0158] The locking ring assembly 510 included within the injection pump assembly 500 may be higher than the locking ring assembly 410 (i.e., as shown by arrow 514), so the locking ring assembly 510 may include a passageway 516 through which the button 506 can pass. Thus, when assembling the reusable housing assembly 502, the locking ring assembly 510 can be placed on top of the main body 508 (in the direction of arrow 518). Once the locking ring assembly 510 is placed on top of the main body 508, one or more locking tabs (not shown) can prevent the locking ring assembly 510 from being removed from the main body 508. Next, the portion of the switch assembly 506 protruding through the passageway 516 is pushed into the main body 508 (in the direction of arrow 520), and thus the installation of the switch assembly 506 can be completed.

[0159] The button 506 is shown at various locations on the injection pump assembly 500, but in other embodiments, the button 506 can be located at any desired location on the injection pump assembly 500.

[0160] Through the use of the locking ring assembly 510, the reusable housing assembly 502 is properly positioned relative to the disposable housing assembly 504 and then releasably engaged by rotating the locking ring assembly 510, thus eliminating the need to rotate the reusable housing assembly 502 relative to the disposable housing assembly 504. Thus, the reusable housing assembly 502 may be properly aligned with the disposable housing assembly 504 prior to engagement, and such alignment must not be disrupted during the engagement process. The locking ring assembly 510 may include a latching mechanism (not shown) that prevents rotation of the locking ring assembly 510 until the reusable housing assembly 502 and the disposable housing assembly 504 are properly positioned relative to each other. The passageway 516 may be elongated to allow movement of the locking ring 510 around the switch assembly 506.

[0161] Referring also to FIGS. 19A-19B and 20-21, various views of an injection pump assembly 500 are shown, which includes a reusable housing assembly 502, a switch assembly 506, and a main body 508. As discussed above, the main body 508 may include a plurality of components, examples of which include a capacitance sensor assembly 148, a printed circuit board 600, a vibration motor assembly 602, a shape memory actuator anchor 604, a switch assembly 506, a battery 606, an antenna assembly 608, a pump assembly 106, a metering valve assembly 610, a capacitance sensor valve assembly 612, and a reservoir valve assembly 614, but are not limited thereto. For clarity, the printed circuit board 600 has been removed from FIG. 19B to allow visualization of the various components located beneath the printed circuit board 600.

[0162] Various electrical components that can be electrically coupled to the printed circuit board 600 may utilize spring-biased terminals that allow for electrical coupling without the need to solder connections. For example, the vibration motor assembly 602 may utilize a pair of spring-biased terminals (one positive terminal and one negative terminal) that are configured to compress corresponding conductive pads on the printed circuit board 600 when the vibration motor assembly 602 is positioned on the printed circuit board 600. However, in the exemplary embodiment, the vibration motor assembly 602 is soldered directly to the printed circuit board.

[0163] As discussed above, the volume sensor assembly 148 can be configured to monitor the amount of fluid being injected by the injection pump assembly 500. For example, the volume sensor assembly 148 can employ acoustic volume sensing, which is the subject of U.S. Pat. Nos. 5,575,310 and 5,755,683, assigned to DEKA Products Limited Partnership, and U.S. Patent Application Publication Nos. US2007 / 0228071A1, US2007 / 0219496A1, US2007 / 0219480A1, and US2007 / 0219597A1, the entire disclosures of which are incorporated herein by reference.

[0164] The vibration motor assembly 602 can be configured to provide a vibration-based signal to a user of the injection pump assembly 500. For example, when the voltage of the battery 606 (which powers the injection pump assembly 500) drops below a minimum allowable voltage, the vibration motor assembly 602 can vibrate the injection pump assembly 500 to provide a vibration-based signal to a user of the injection pump assembly 500. The shape memory actuator anchor 604 can provide a mounting point for the shape memory actuator described above (e.g., the shape memory actuator 112). As discussed above, the shape memory actuator 112 can be, for example, a conductive shape memory alloy wire that changes shape with temperature. The temperature of the shape memory actuator 112 can be changed by a heater or, more conveniently, by the application of electrical energy. Thus, one end of the shape memory actuator 112 can be rigidly attached (i.e., affixed) to the shape memory actuator anchor 604, and the other end of the shape memory actuator 112 can be applied to, for example, a valve assembly and / or a pump actuator. Thus, by applying electrical energy to the shape memory actuator 112, the length of the shape memory actuator 112 can be controlled, and thus the valve assembly and / or pump actuator to which it is attached can be operated.

[0165] The antenna assembly 608 can be configured to enable wireless communication, for example, between the infusion pump assembly 500 and the remote control assembly 300 (FIG. 11). As discussed above, the remote control assembly 300 can enable a user to program the infusion pump assembly 500, for example, to configure a bolus infusion event. As discussed above, the infusion pump assembly 500 can include one or more valve assemblies configured to control the flow rate of an injectable fluid through a fluid path (within the infusion pump assembly 500), and the pump assembly 106 can be configured to deliver the injectable fluid from the fluid path to the user. In a particular embodiment of this infusion pump assembly 500, the infusion pump assembly 500 is shown to include three valve assemblies, namely, a measurement valve assembly 610, a volume sensor valve assembly 612, and a reservoir valve assembly 614.

[0166] As discussed above and with reference also to FIG. 21, the injectable fluid can be stored within the reservoir 118. To achieve delivery of the injectable fluid to the user, processing logic (not shown) included within the infusion pump assembly 500 can energize a shape memory actuator 112 that can be secured onto one end using a shape memory actuator anchor 604. Referring also to FIG. 22A, the shape memory actuator 112 can effect activation of the pump assembly 106 and the reservoir valve assembly 614. The reservoir valve assembly 614 can include a reservoir valve actuator 614A and a reservoir valve 614B, and activation of the reservoir valve assembly 614 can effect a downward displacement of the reservoir valve actuator 614A and closure of the reservoir valve 614B, which can effect isolation of the reservoir 118. Further, the pump assembly 106 can include a pump plunger 106A and a pump chamber 106B, and activation of the pump assembly 106 can effect downward displacement of the pump plunger 106A into the pump chamber 106B, which can effect displacement of the injectable fluid (in the direction of arrow 616).

[0167] The volume sensor valve assembly 612 can include a volume sensor valve actuator 612A and a volume sensor valve 612B. Referring also to FIG. 22B, the volume sensor valve actuator 612A can be closed via a spring assembly that provides a mechanical force to seal the volume sensor valve 612B. However, when the pump assembly 106 is activated, if the displaced injectable fluid is at a pressure sufficient to overcome the mechanical sealing force of the volume sensor valve assembly 612, the displacement of the injectable fluid occurs in the direction of arrow 618. This can result in the filling of the volume sensor chamber 620 contained within the volume sensor assembly 148. Through the use of the speaker assembly 622, the port assembly 624, the reference microphone 626, the spring diaphragm 628, and the variable capacitance microphone 630, the volume sensor assembly 148 can determine the dose of injectable fluid contained within the volume sensor chamber 620.

[0168] Referring also to FIG. 22C, once the volume of injectable fluid contained within the volume sensor chamber 620 has been calculated, the shape memory actuator 632 can be energized, resulting in the activation of the measurement valve assembly 610, which can include a measurement valve actuator 610A and a measurement valve 610B. Once activated, and by the mechanical energy exerted on the injectable fluid within the volume sensor chamber 620 by the spring diaphragm 628, the injectable fluid within the volume sensor chamber 620 can be displaced into the user's body (in the direction of arrow 634) through the disposable cannula 138.

[0169] Referring also to FIG. 23, an exploded view of the infusion pump assembly 500 is shown. The shape memory actuator 632 may be secured to the shape memory actuator anchor 636 (at the first end). Additionally, the other end of the shape memory actuator 632 may be used to provide mechanical energy to the valve assembly 638, which may activate the metering valve assembly 610. The capacitance sensor assembly spring retainer 642 may properly position the capacitance sensor assembly 148 relative to various other components of the infusion pump assembly 500. The valve assembly 638 may be used in conjunction with the shape memory actuator 112 to activate the pump plunger 106A. The metering valve 610B, the capacitance sensor valve 612B, and / or the reservoir valve 614B may be built-in valves configured to allow installation during the assembly of the infusion pump assembly 500 by pushing the valve upward into the lower surface of the main body 508.

[0170] Referring also to FIGS. 24 and 25A-25D, a more detailed view of the pump assembly 106 is shown. The pump actuator assembly 644 may include a pump actuator support structure 646, a biasing spring 648, and a lever assembly 650.

[0171] Referring also to FIGS. 26A-26B and 27A-27B, a more detailed view of the metering valve assembly 610 is shown. As discussed above, the valve assembly 638 may activate the metering valve assembly 610.

[0172] Referring also to FIGS. 28A - 28D, the injection pump assembly 500 may include a metering valve assembly 610. As discussed above, the valve assembly 638 may be actuated via the shape memory actuator 632 and the actuator assembly 640. Thus, in order to inject the volume of injectable fluid stored within the volume sensor chamber 620, the shape memory actuator 632 may need to actuate the valve assembly 638 for a fairly long period of time (e.g., one minute or more). Since this consumes a significant amount of power from the battery 606, the metering valve assembly 610 may allow for temporary actuation of the valve assembly 638, at which point the metering valve latch 656 may prevent the valve assembly 638 from returning to its unactuated position. The shape memory actuator 652 may be secured on a first end using the electrical contact 654. The other end of the shape memory actuator 652 may be connected to the valve latch 656. When the shape memory actuator 652 is actuated, the shape memory actuator 652 may pull the valve latch 656 forward and release the valve assembly 638. As such, the metering valve assembly 610 may be actuated via the shape memory actuator 632. Once the metering valve assembly 610 is activated, the valve latch 656 may automatically latch onto the valve assembly 638 in the actuated position. By operating the shape memory actuator 652, the valve latch 656 may be pulled forward and the valve assembly 638 may be released. Assuming that the shape memory actuator 632 is no longer actuated, when the valve latch 656 releases the valve assembly 638, the metering valve assembly 610 will be in an inoperative state. Thus, through the use of the metering valve assembly 610, the shape memory actuator 632 does not need to be actuated for the entire time required to inject the volume of injectable fluid stored within the volume sensor chamber 620.

[0173] As discussed above, the injection pump assemblies (e.g., injection pump assemblies 100, 100’, 400, 500) may include an external injection set 134 configured to deliver injectable fluid to a user. The external injection set 134 may include a cannula assembly 136 that may include a needle or a disposable cannula 138, and a tubing assembly 140, which may also be referred to as a tubing set. The tubing assembly 140 may be in fluid communication with the reservoir 118, for example, through a fluid path, and with the cannula assembly 138, for example, directly or through a cannula interface 142.

[0174] Referring also to FIG. 29, an alternative embodiment injection pump assembly 700 is shown that is configured to store a portion of the tubing assembly 140. Specifically, the injection pump assembly 700 may include a peripheral tubing storage assembly 702 configured to allow a user to wind a portion of the tubing assembly 140 around the periphery of the injection pump assembly 700 (similar to winding a yo-yo). The peripheral tubing storage assembly 702 may be positioned around the periphery of the injection pump assembly 700. The peripheral tubing storage assembly 702 may be configured as an open trough into which a portion of the tubing assembly 140 may be wound. Alternatively, the peripheral tubing storage assembly 702 may include one or more split portions 704, 706 that form a plurality of narrower troughs sized to create an interference fit between the walls of the narrower troughs and the outer surface of a portion of the tubing 140. When the peripheral tubing storage assembly 705 includes the plurality of split portions 704, 706, the resulting narrower troughs may be wound in a helical pattern around the periphery of the injection pump assembly 700 (similar to the threads of a screw).

[0175] Referring also to FIGS. 30-31, an alternative embodiment injection pump assembly 750 is shown that is configured to store a portion of the tubing assembly 140. Specifically, the injection pump assembly 750 may include a peripheral tubing storage assembly 752 that is configured to allow a user to wind a portion of the tubing assembly 140 around the injection pump assembly 750 (again, similar to a yo-yo). The peripheral tubing storage assembly 752 may be positioned around the injection pump assembly 750. The peripheral tubing storage assembly 752 may be configured as an open valley into which a portion of the tubing assembly 140 may be wound. Alternatively, the peripheral tubing storage assembly 752 may include one or more split portions 754, 756 that form a plurality of narrower valleys that may be sized to create an interference fit between the walls of the narrower valleys and the outer surface of a portion of the tubing 140. When the peripheral tubing storage assembly 752 includes the plurality of split portions 754, 756, the resulting narrower valleys may be wound in a helical pattern around the injection pump assembly 750 (again, similar to the threads of a screw).

[0176] The injection pump assembly 750 may include a tubing retainer assembly 758. The tubing retainer assembly 758 may be configured to releasably secure the tubing assembly 140 so as to prevent the tubing assembly 140 from unwinding from around the injection pump assembly 750. In one embodiment of the tubing retainer assembly 758, the tubing retainer assembly 758 may include a downwardly directed pin assembly 760 that is positioned above an upwardly directed pin assembly 762. The combination of the pin assemblies 760, 762 may define a “pinch point” through which the tubing assembly 140 may be pushed. Thus, a user may wrap the tubing assembly 140 around the periphery of the injection pump assembly 750, and each loop of the tubing assembly 140 is secured within the peripheral tubing storage assembly 752 via the tubing retainer assembly 758. If the user desires to lengthen an unsecured portion of the tubing assembly 140, the user may release one loop of the tubing assembly 140 from the tubing retainer assembly 758. Conversely, if the user desires to shorten an unsecured portion of the tubing assembly 140, the user may secure an additional loop of the tubing assembly 140 within the tubing retainer assembly 758.

[0177] Referring also to FIGS. 32-33, an exemplary embodiment of an injection pump assembly 800 is shown. Similar to the injection pump assemblies 100, 100', 400, and 500, the injection pump assembly 800 may include a reusable housing assembly 802 and a disposable housing assembly 804.

[0178] Referring also to FIGS. 34A-34B, similar to the injection pump assembly 100, the reusable housing assembly 802 can be configured to releasably engage the disposable housing assembly 804. Such a releasable engagement can be achieved, for example, by a screw-type, twist-lock, or compression fit configuration. The injection pump assembly 800 can include a locking ring assembly 806. For example, the reusable housing assembly 802 may be properly positioned relative to the disposable housing assembly, and the locking ring assembly 806 can be rotated to releasably engage the reusable housing assembly 802 and the disposable housing assembly 804.

[0179] The locking ring assembly 806 can include a knob 808 that can facilitate rotation of the locking ring assembly 806. Additionally, for example, the position of the knob 808 relative to the tab 810 of the disposable housing assembly 804 can provide evidence that the reusable housing assembly 802 is fully engaged with the disposable housing assembly 804. For example, as shown in FIG. 34A, when the reusable housing assembly 802 is properly aligned with the disposable housing assembly 804, the knob 808 can be aligned with the tab 810 in a first position. Upon achieving a fully engaged state, rotation of the locking ring assembly 806 can cause the knob 808 to be aligned with the tab 810 in a second position, as shown in FIG. 34B.

[0180] Referring also to FIGS. 35A - 35C and FIGS. 36 - 38A, similar to the reusable housing assembly 102, the reusable housing assembly 802 may include a machine control assembly 812 (e.g., may include a valve assembly 814 shown in FIG. 36, including one or more valves and one or more pumps for delivering and controlling the flow rate of an injectable fluid). The reusable housing assembly 802 may also include an electrical control assembly 816 configured to provide control signals to the machine control assembly 812 to achieve delivery of the injectable fluid to the user. The valve assembly 814 may be configured to control the flow rate of the injectable fluid through the fluid path, and the pump assembly may be configured to deliver the injectable fluid from the fluid path to the user.

[0181] The machine control assembly 812 and the electrical control assembly 816 may be contained within a housing defined by a substrate 818 and a body 820. In some embodiments, one or more of the substrate 818 and the body 820 may provide electromagnetic shielding. In such embodiments, the electromagnetic shielding may prevent and / or reduce electromagnetic interference received and / or generated by the electrical control assembly 816. Additionally / alternatively, as shown in FIGS. 36 and 37, an EMI shield 822 may be included. The EMI shield 822 may provide shielding against electromagnetic interference generated and / or received.

[0182] The reusable housing assembly 802 may include a switch assembly configured to receive user commands (e.g., for bolus delivery, pairing with a remote control assembly, or the like). The switch assembly may include a button 824 that may be disposed in an opening 826 of the body 820. For example, as shown in FIG. 35B, the locking ring assembly 806 may include a radial slot 828 configured to allow the locking ring assembly 806 to be rotated relative to the body 820 while still providing easy access to the button 824.

[0183] Referring also to FIGS. 39A - 39C, the electrical control assembly 816 may include a printed circuit board 830 as well as a battery 832. The printed circuit board 830 may include various control electronics for monitoring and controlling the amount of injectable fluid that has been delivered and / or is being delivered. For example, the electrical control assembly 816 may measure the amount of injectable fluid that has just been dispensed and determine whether sufficient injectable fluid has been dispensed based on the dosage required by the user. If sufficient injectable fluid has not been dispensed, the electrical control assembly 816 may determine that more injectable fluid should be delivered. The electrical control assembly 816 may provide an appropriate signal to the mechanical control assembly 812 so that additional required dosages can be delivered, or the electrical control assembly 816 may provide an appropriate signal to the mechanical control assembly 812 so that additional dosages can be dispensed along with the next dosage. Alternatively, if an excessive amount of injectable fluid has been dispensed, the electrical control assembly 816 may provide an appropriate signal to the mechanical control assembly 812 so that less injectable fluid can be dispensed along with the next dosage. The electrical control assembly 816 may include one or more microprocessors. In an exemplary embodiment, the electrical control assembly 816 may include three processors. One processor (which may include, but is not limited to, a CC2510 microcontroller / RF transceiver available from Chipcon AS (Oslo, Norway), for example) may be dedicated to wireless communication, for example, to communicate with a remote control assembly. Two additional microprocessors (examples of which may include, but are not limited to, an MSP430 microcontroller available from Texas Instruments Inc. (Dallas, Texas)) may be dedicated to issuing and executing commands (such as dispensing a dosage of injectable fluid, processing feedback signals from a volume measurement device, and performing equivalents).

[0184] As shown in FIG. 35C, the substrate 818 can provide access to electrical contacts 834 that can be electrically coupled to the electrical control assembly 816, for example, to recharge the battery 832. The substrate 818 can include one or more features (e.g., openings 836, 838) configured to facilitate proper alignment with the disposable housing assembly 804 through cooperative features (e.g., tabs) of the disposable housing assembly 804. Additionally, as shown in FIGS. 40A-40C, 41A-41B, and 42A-42C, the substrate 818 can include various features for mounting the valve assembly 814 and the electrical control assembly 816 and for providing access to the disposable housing assembly 804 by the valve assembly 814.

[0185] The locking ring assembly 806 can include gripping inserts 840, 842 that can include, for example, an elastomeric or molded material to facilitate gripping and twisting of the locking ring assembly 806, for example, to engage / disengage the reusable housing assembly 802 and the disposable housing assembly 804. Additionally, the locking ring assembly 806 can include sensing components (e.g., magnet 844) that can interact with components of the reusable housing assembly 802 (e.g., Hall effect sensor) to provide, for example, an indication of the nature of the mating components (e.g., which can include, but is not limited to, one or more of the disposable housing assembly 804, the charging station, or the filling station in some embodiments) and / or whether the reusable housing assembly 802 is properly engaged with the mating components. In an exemplary embodiment, a Hall effect sensor (not shown) can be located on the pump printed circuit board. The Hall effect sensor can detect when the locking ring has been rotated to the closed position. Thus, the Hall effect sensor, together with the magnet 844, can provide a system for determining whether the locking ring has been rotated to the closed position.

[0186] The sensing component (magnet) 844 can operate to provide a determination as to whether a reusable housing assembly component, i.e., in an exemplary embodiment, a component or device with which a reusable housing assembly is intended, is properly attached, along with a Hall effect sensor. The locking ring assembly 806 shall not rotate without being attached to a component, i.e., a disposable housing assembly 804, a dust cover, or a charger. Thus, the sensing component, along with the reusable housing assembly component, can function to provide many advantageous safety features to the infusion pump system. These features may include, but are not limited to, one or more of the following. If the system does not detect that it is not attached to a disposable assembly, a dust cover, or a charger, the system may notify, warn, or alert the user because reusable parts, such as valves and pump components, may be susceptible to contamination or damage that could compromise the integrity of the reusable assembly. Thus, the system can provide an integrity alarm to warn the user about potential threats to the integrity of the reusable assembly. Also, if the system senses that the reusable assembly is attached to a dust cover, the system can turn off or reduce the power to conserve power. This can provide for more efficient use of power when the reusable assembly is not connected to components that need to interact.

[0187] The reusable housing assembly 802 can be attached to a number of different components, including but not limited to a disposable housing assembly, a dust cover, or a battery charger / battery charging station. In each case, the hall effect sensor can detect that the locking ring is in the closed position and thus that the reusable housing assembly 802 is releasably engaged with a disposable housing assembly, a dust cover, or a battery charger / battery charging station (or another component). The infusion pump system can determine the component to which it is attached by using an AVS system (which may also be referred to as a volume measurement sensor) described in more detail below or by electrical contacts. Referring also to FIGS. 38B - 38D, one embodiment of a dust cover (e.g., dust cover 839) is shown. In an exemplary embodiment, the dust cover 839 can include features 841, 843, 845, 847 such that the locking ring of the reusable housing assembly 802 can be releasably engaged with the dust cover 839. Additionally, the dust cover 839 can further include a recessed region 849 for accommodating the valve and pump features of the reusable housing assembly 804. For example, with respect to the dust cover, the AVS system can determine that the dust cover, rather than the disposable housing assembly, is connected to the reusable housing assembly. The AVS system can distinguish between using a reference table or other comparison data and comparing the measurement data to data for a characteristic dust cover or an empty disposable housing assembly. With respect to the battery charger, the battery charger can include electrical contacts in an exemplary embodiment. When the reusable housing assembly is attached to the battery charger, the infusion pump assembly electronic system may sense that contact has been made and thus indicate that the reusable housing assembly is attached to the battery charger.

[0188] Referring also to FIGS. 43A-45B and FIGS. 44A-44C, an embodiment of a valve assembly 814 is shown that may include one or more valves and one or more pumps. Similar to injection pump assemblies 100, 100', 400, and 500, valve assembly 814 may generally include a reservoir valve 850, a plunger pump 852, a volume sensor valve 854, and a measurement valve 856. Similar to the previous description, reservoir valve 850 and plunger pump 852 may be actuated by a shape memory actuator 858 that may be secured to a shape memory actuator anchor 860 (at the first end). Additionally, measurement valve 856 may be actuated via valve actuator 862 by a shape memory actuator 864 that may be secured to a shape memory actuator anchor 866 (at the first end). Similar to as discussed above, the measurement valve may be maintained in an open position via a measurement valve latch assembly 868. Measurement valve 856 may be released via activation of a shape memory actuator 870 that may be secured by a shape memory actuator anchor 872 (at the first end). In some embodiments, shape memory actuator anchor 860 may be placed within a reusable housing assembly. By using this process during manufacturing, it is ensured that the shape memory length actuator 858 is installed and maintains the desired length and tension / strain.

[0189] Referring also to FIGS. 45A-45B and FIGS. 46A-46E, shape memory actuator 858 (which may include, for example, one or more shape memory wires) may actuate plunger pump 852 via actuator assembly 874. Actuator assembly 874 may include a biasing spring 876 and a lever assembly 878. Actuator assembly 874 may actuate both plunger pump 852 and measurement valve 850.

[0190] Referring also to FIGS. 47A - 47B, the measurement valve 856 can be actuated by a shape memory actuator 864 via a valve actuator 862 and a lever assembly 878. Once actuated, the measurement valve latch assembly 868 can hold the measurement valve 856 in the open position. The measurement valve latch assembly 868 is actuated by a shape memory actuator 870 to release the measurement valve 856, enabling it to return to the closed position.

[0191] The disposable housing assembly 804 can be configured for single - use or for use for a specified period, such as, for example, three days or any other amount of time. The disposable housing assembly 804 can be configured such that any component within the infusion pump assembly 800 that contacts the injectable fluid can be disposed on top of and / or inside the disposable housing assembly 804. As such, the risk of contaminating the injectable fluid can be reduced.

[0192] Referring also to FIGS. 48 and 49A - 49C, the disposable housing assembly 804 can include a base portion 900, a membrane assembly 902, and a top portion 904. The base portion 900 can include a recess 906 that, together with the membrane assembly 902, defines a reservoir 908 for receiving an injectable fluid (not shown), such as insulin. Referring also to FIGS. 50A - 50C, the recess 906 can be at least partially formed by and integral with the base portion 900. The membrane assembly 902 can be in sealed engagement with the base portion 900, for example, by being compression - clamped between the base portion 900 and the top portion 904. The top portion 904 can be attached to the base portion 900 by conventional means such as adhesion, heat - fusion, ultrasonic welding, and compression fitting. Additionally / alternatively, the membrane assembly 902 can be attached to the base portion 900 via, for example, adhesion, ultrasonic welding, heat - fusion, and equivalents to provide a seal between the membrane assembly 902 and the base portion 900.

[0193] Still referring to FIGS. 48 and 50A, in the exemplary embodiment, the recess 906 includes a raised portion 901 that includes a region 903 around a fluid opening 905 that leads to a fluid line. The raised portion 901 extends around the recess 906 in the exemplary embodiment. However, in other embodiments, the raised portion 901 may not extend all the way around, but may be partially around. The region 903 around the fluid opening 905 may include an angled portion that includes an angle of 45 degrees and may be shaped as shown in the exemplary embodiment, but in other embodiments, the angle may be larger or smaller. In some embodiments, the pump may not generate enough vacuum to fold the reservoir to expel the entire volume of fluid stored therein. The raised portion 901 may act to minimize wasted fluid.

[0194] In the exemplary embodiment, the fluid opening 905, which may include three openings in the exemplary embodiment but may include more or fewer openings in other embodiments, may be surrounded by the region 903 of the raised portion. In the exemplary embodiment, the fluid opening 905 may have a narrow center and thus generate surface tension that can prevent air from being drawn into the opening. In the exemplary embodiment, this region may be designed to encourage air in the reservoir to be drawn above one of the fluid openings 905 rather than through the fluid opening 905 into the fluid line. Additionally, since there may be more than one fluid opening 905, if a bubble is trapped above one opening, the air may not prevent fluid from flowing through the other two openings.

[0195] Referring also to FIGS. 51A - 51C, the disposable housing assembly 804 may also include a fluid path cover 910. The fluid path cover 910 may be received within a cavity 912 formed above / inside the base portion 900. The fluid path cover 910 may, in some embodiments, include at least a portion of one or more channels (e.g., channel 914). The channels included in the fluid path cover 910 may fluidly couple one or more volcano valve features (e.g., volcano valve 916) included above the base portion 900. The volcano valve 916 may include a protrusion having an opening extending therethrough. Additionally, the fluid path cover 910 and the base portion 900 may each define a portion of a recess (e.g., recessed portions 918, 920 included in the base portion 900 and the fluid path cover 910, respectively) for fluidly coupling to an infusion set (e.g., including cannula 922). The cannula 922 may be coupled to the disposable housing assembly 804 by conventional means (e.g., adhesion, heat fusion, compression fitting, or the like). The fluid path defined by the volcano valves (e.g., volcano valve 916) of the fluid path cover 910 and the base portion 900 may define a fluid path between the reservoir 908 and the cannula 922 for delivery of injectable fluid to the user via the infusion set. However, in some embodiments, the fluid path cover 910 may include at least a portion of the fluid path, and in some embodiments, the fluid path cover 910 may not include at least a portion of the fluid path. In an exemplary embodiment, the fluid path cover 910 may be laser welded to the base portion 900. However, in other embodiments, the fluid path cover 910 may also be connected to the base portion 900 by conventional means (e.g., adhesion, heat fusion, ultrasonic welding, compression fitting, or the like) to achieve a substantially fluid - tight seal between the fluid path cover 910 and the base portion 900.

[0196] Referring also to FIGS. 54A - 54C, the disposable housing assembly 804 may further include a valve membrane cover 924. The valve membrane cover 924 may be disposed at least partially over a volcano valve (e.g., volcano valve 916) and a pump recess 926 included above / inside the base portion 900. The valve membrane cover 924 may include a flexible material that can be selectively engaged, for example, with the volcano valve by a reservoir valve 850, a volume sensor valve 854, and a measurement valve 856 of the reusable housing assembly 802, for example, to control the flow rate of an injectable fluid. Additionally, the valve membrane cover 924 may be elastically deformed into the pump recess 926 by a plunger pump 852 to achieve the delivery of an injectable fluid. The valve membrane cover 924 may be engaged between the base portion 900 and the uppermost portion 904 of the disposable housing assembly 804 to form a seal 928 between the valve membrane cover 924 and the base portion 900. For example, in an exemplary embodiment, the valve membrane cover 924 may be externally coated over the base portion 900. In other embodiments, the valve membrane cover 924 may be compression-clamped between the base portion 900 and the uppermost portion 904 to form the seal 928. Additionally / alternatively, the valve membrane insert may be connected to one or more of the base portion 900 and the uppermost portion 904, for example, by adhesion, heat fusion, or the like.

[0197] Referring also to FIGS. 53A - C, the top portion 904 may include alignment tabs 930, 932 configured to be at least partially received within openings 836, 838 of the substrate 818 of the reusable housing assembly 802 so as to ensure proper alignment between the reusable housing assembly 802 and the disposable housing assembly 804. Additionally, the top portion 904 may include one or more radial tabs 934, 936, 938, 940 configured to be engaged by the cooperating tabs 942, 944, 946, 948 of the locking ring assembly 806. One or more of the radial tabs (e.g., radial tab 940) may include a stop (e.g., alignment tab stop 950, which may be used for welding, a tab that fits into a recess for positioning and ultrasonic welding) that may prevent further rotation of the locking ring assembly 806 once the reusable housing assembly 802 and the disposable housing assembly 804 are fully engaged.

[0198] As discussed above, the valve membrane insert 924 may enable the delivery and flow of injectable fluids by the reservoir valve 850, the plunger pump 852, the volume sensor valve 854, and the measurement valve 856. Accordingly, the top portion 904 may include one or more openings (e.g., openings 952, 954, 956) that may expose at least a portion of the valve membrane insert 924 for actuation by the reservoir valve 850, the plunger pump 852, the volume sensor valve 854, and the measurement valve 856. Additionally, the top portion 904 may include one or more openings 958, 960, 962 configured to enable control of the fill volume during filling of the reservoir 908, as discussed in more detail below. The reservoir assembly 902 may include ribs 964, 966, 968 (e.g., as shown in FIG. 52A) that may be at least partially received within each of the openings 958, 960, 962. As discussed in more detail below, a force may be applied to one or more of the ribs 964, 966, 968 to at least temporarily reduce the volume of the reservoir 908.

[0199] In some embodiments, it may be desirable to provide a seal between the reusable housing assembly 802 and the disposable housing assembly 804. Thus, the disposable housing assembly 804 may include a sealing assembly 970. The sealing assembly 970 may include, for example, an elastomeric member that, when engaged, may provide a compressible rubber or plastic layer between the reusable housing assembly 802 and the disposable housing assembly 804, and thus may prevent accidental disengagement and penetration by external fluids. For example, the sealing assembly 970 may be a watertight assembly, and thus may enable a user to wear the infusion pump assembly 800 while swimming, bathing, or exercising.

[0200] For example, similar to the disposable housing assembly 114, the disposable housing assembly 804 may be configured to be filled a plurality of times with the reservoir 908 in some embodiments. However, in some embodiments, the disposable housing assembly 114 may be configured such that the reservoir 908 may not need to be refilled. Referring also to FIGS. 57 - 64, the fill adapter 1000 may be configured to be coupled to the disposable housing assembly 804 to refill the reservoir 908 using a syringe (not shown). The fill adapter 1000 may include locking tabs 1002, 1004, 1006, 1008 configured to engage the radial tabs 934, 936, 938, 940 of the disposable housing assembly 804, substantially similar to the tabs 942, 944, 946, 948 of the locking ring assembly 806. Thus, the fill adapter 1000 may be releasably engaged with the disposable housing assembly 804 by aligning the fill adapter 1000 with the disposable housing assembly 804 and rotating the fill adapter 1000 and the disposable housing assembly 804 relative to each other to releasably engage the locking tabs 1002, 1004, 1006, 1008 with the radial tabs 934, 936, 938, 940.

[0201] The filling adapter 1000 may further include a filling aid 1010, which may be, for example, a guide passage 1012 configured to direct a needle of a syringe (not shown) to a partition wall of the disposable housing assembly 804 to enable the reservoir 908 of the disposable housing assembly 804 to be filled by the syringe. In some embodiments, the guide passage 1012 may be an angled ramp or other stepped angled ramp to further direct the syringe to the partition wall. The filling adapter 1000 may facilitate filling the reservoir 908, for example, by providing a relatively large insertion area at the distal opening of the guide passage 1012. The guide passage 1012 may generally taper to a smaller proximal opening that can be properly aligned with the partition wall of the disposable housing assembly 804 when the filling adapter 1000 is engaged with the disposable housing assembly 804. Thus, the filling adapter 1000 can reduce the dexterity and aiming required to properly insert the needle through the partition wall of the disposable housing assembly 804 for the purpose of filling the reservoir 908.

[0202] As discussed above, the disposable housing assembly 804 may be configured to facilitate controlling the amount of injectable fluid delivered to the reservoir 908 during filling. For example, the membrane assembly 902 of the disposable housing assembly 804 may include ribs 964, 966, 968 that can be depressed and displaced at least partially into the reservoir 908, thereby reducing the volume of the reservoir 908. Thus, when injectable fluid is delivered to the reservoir 908, the volume of fluid that can be contained by the reservoir 908 can be correspondingly reduced. The ribs 964, 966, 968 may be accessible through openings 958, 960, 962 in the uppermost portion 904 of the disposable housing assembly 804.

[0203] The filling adapter 1000 may include one or more button assemblies (e.g., button assemblies 1014, 1016, 1018) corresponding to ribs 964, 966, 968. That is, when the filling adapter 1000 is releasably engaged with the disposable housing assembly 804, the buttons 1014, 1016, 1018 may be aligned with the ribs 964, 966, 968. The button assemblies 1014, 1016, 1018 may be, for example, cantilever members that can be depressed. When the filling adapter 1000 is releasably engaged with the disposable housing assembly 804, one or more of the button assemblies 1014, 1016, 1018 may be depressed, and correspondingly, one of each of the ribs 964, 966, 968 may be displaced into the reservoir 908, causing an attendant reduction in the volume of the reservoir 908.

[0204] For example, for illustrative purposes, assume that the reservoir 908 has a maximum capacity of 3.00 mL. Further, assume that the button assembly 1014 is configured to displace the rib 964 into the disposable housing assembly 804, resulting in a 0.5 mL reduction in the 3.00 mL capacity of the disposable housing assembly 804. Further, assume that the button assembly 1016 is configured to displace the rib 966 into the disposable housing assembly 804, similarly resulting in a 0.5 mL reduction in the 3.00 mL capacity of the disposable housing assembly 804. Further, assume that the button assembly 1018 is configured to displace the slot assembly 968 into the disposable housing assembly 804, similarly resulting in a 0.5 mL reduction in the 3.00 mL capacity of the disposable housing assembly 804. Thus, if a user desires to fill the reservoir 908 within the disposable housing assembly 804 with 2.00 mL of injectable fluid, in some embodiments, the user may first fill the reservoir to its 3.00 mL capacity and then depress the button assemblies 1016 and 1014 (which causes displacement of the rib 966 into the disposable housing assembly 804), effectively reducing the 3.00 mL capacity of the reservoir 908 within the disposable housing assembly 804 to 2.00 mL. In some embodiments, the user may first depress each respective number of button assemblies to effectively reduce the capacity of the reservoir 908 and then fill the reservoir 908. Although a specific number of button assemblies are shown to represent exemplary embodiments, in other embodiments, the number of button assemblies can vary from a minimum of 1 to as many as desired. Additionally, for illustrative purposes and in the exemplary embodiments, each button assembly can displace 0.5 mL, but in other embodiments, the displacement volume per button can vary. Additionally, the reservoir can include a capacity that is larger or smaller than that described in the exemplary embodiments in various embodiments.

[0205] According to the above configuration, at least partially, a button assembly (e.g., button assemblies 1014, 1016, 108) can be employed to control the filling capacity of the reservoir 908. By not pressing any of the button assemblies, the maximum filling capacity of the reservoir 908 can be achieved. Pressing one button assembly (e.g., button assembly 1014) can enable the achievement of a second maximum filling capacity. Pressing two button assemblies (e.g., button assemblies 1014, 1016) can achieve a third maximum filling capacity. Pressing all three button assemblies (e.g., button assemblies 1014, 1016, 1018) can enable the achievement of the minimum filling capacity.

[0206] Furthermore, in an embodiment, button assemblies 1014, 1016, 1018 can be utilized to at least partially facilitate the filling of the reservoir 908. For example, once a filling needle (which can be fluidly connected to a vial of injectable fluid) is inserted into the reservoir 908, the button assemblies 1014, 1016, 1018 can be pressed to send at least a portion of the air contained within the reservoir into the vial of injectable fluid. The button assemblies 1014, 1016, 1018 can later be released to allow the injectable fluid to flow from the vial into the reservoir 908. Once the reservoir 908 is filled with the injectable fluid, one or more of the button assemblies (one or more of button assemblies 1014, 1016, 1018) may be pressed, thereby pushing out at least a portion of the injectable fluid from the reservoir 908 (e.g., via a needle used to fill the reservoir 908 and return to the vial of injectable fluid). As discussed above, the volume of the injectable fluid contained within the reservoir 908 can be controlled (e.g., control how much injectable fluid is pushed back into the vial of injectable fluid) depending on, for example, how many button assemblies are pressed.

[0207] Referring particularly to FIGS. 62 - 64, filling aid 1010 may be pivotally coupled to filling adapter substrate 1020. For example, filling aid 1010 may include pivot members 1022, 1024 configured to be received within pivot supports 1026, 1028, thereby enabling the filling aid to pivot between an open position (e.g., as shown in FIGS. 57 - 61) and a closed position (e.g., as shown in FIGS. 63 - 64). The closed position may be suitable, for example, for packaging the filling adapter 1000, storing the filling adapter 1000, or the like. To ensure that the filling aid 1010 is properly oriented for filling reservoir 908, filling adapter 1000 may include support member 1030. To properly orient the filling aid 1010, the user may pivot the filling aid 1010 to the fully open position, and the filling aid 1010 may contact the support member 1030.

[0208] According to an alternative embodiment, also referring to FIG. 65, filling adapter 1050 may be configured to releasably engage disposable housing assembly 804 via a plurality of locking tabs (e.g., locking tabs 1052, 1054). Additionally, filling adapter 1050 may include a plurality of button assemblies (e.g., button assemblies 1056, 1058, 1060) that interact with ribs 964, 966, 968 of disposable housing assembly 804 to adjust the filling volume of reservoir 908. Filling adapter 1050 may further include a filling aid 1062 having a guide passage 1064 configured to align the needle of a syringe with the partition of disposable housing 804 for the purpose of accessing reservoir 908 to fill it with, for example, an injectable fluid. Filling aid 1062 may be connected to substrate 1066, for example, as an integral component thereof, by adhesion, heat fusion, compression fitting, or the like.

[0209] Referring also to FIGS. 66 - 74, the vial filling adapter 1100 can be configured to facilitate filling the reservoir 908 of the disposable housing assembly 804 directly from the vial. Similar to the filling adapter 1000, the vial filling adapter 1100 can include locking tabs 1102, 1104, 1106, 1108 configured to engage the radial tabs 934, 936, 938, 940 of the disposable housing assembly in substantially the same manner as the tabs 942, 944, 946, 948 of the locking ring assembly 806. Thus, the vial filling adapter 1100 can be releasably engaged with the disposable housing assembly 804 by aligning the vial filling adapter 1100 with the disposable housing assembly 804 and rotating the filling adapter 1100 and the disposable housing assembly 804 relative to each other to releasably engage the locking tabs 1102, 1104, 1106, 1108 with the radial tabs 934, 936, 938, 940.

[0210] As discussed above, the disposable housing assembly 804 can be configured to facilitate controlling the amount of injectable fluid delivered to the reservoir 908 during filling. For example, the membrane assembly 902 of the disposable housing assembly 804 may include ribs 964, 966, 968 that can be depressed and displaced at least partially into the reservoir 908, thereby reducing the volume of the reservoir 908. Thus, when injectable fluid is delivered to the reservoir 908, the volume of fluid that can be contained by the reservoir 908 can be correspondingly reduced. The ribs 964, 966, 968 can be accessible through the openings 958, 960, 962 in the uppermost portion 904 of the disposable housing assembly 804.

[0211] The vial filling adapter 1100 may include one or more button assemblies (e.g., button assemblies 1110, 1112, 1114) corresponding to ribs 964, 966, 968 (as shown in FIG. 52A). That is, when the vial filling adapter 1100 is releasably engaged with the disposable housing assembly 804, the buttons 1110, 1112, 1114 can be aligned with the ribs 964, 966, 968. The button assemblies 1110, 1112, 1114 can be, for example, cantilever members that can be depressed. When the vial filling adapter 1100 is releasably engaged with the disposable housing assembly 804, one or more of the button assemblies 1110, 1112, 1114 may be depressed, and correspondingly, one of each of the ribs 964, 966, 998 can be displaced into the reservoir 908, thereby reducing the volume of the reservoir 908.

[0212] For example, for illustrative purposes, assume that the reservoir 908 has a maximum capacity of 3.00 mL. Further, assume that the button assembly 1110 is configured to displace the rib 964 into the disposable housing assembly 804, resulting in a 0.5 mL reduction in the 3.00 mL capacity of the disposable housing assembly 804. Further, assume that the button assembly 1112 is configured to displace the rib 966 into the disposable housing assembly 804, likewise resulting in a 0.5 mL reduction in the 3.00 mL capacity of the disposable housing assembly 804. Further, assume that the button assembly 1114 is configured to displace the rib 968 into the disposable housing assembly 804, likewise resulting in a 0.5 mL reduction in the 3.00 mL capacity of the disposable housing assembly 804. Thus, if a user desires to fill the reservoir 908 within the disposable housing assembly 804 with 2.00 mL of injectable fluid, depressing the button assemblies 1112 and 1114 (resulting in the displacement of the ribs 966 and 968 into the disposable housing assembly 804) can effectively reduce the 3.00 mL capacity of the reservoir 908 within the disposable housing assembly 804 to 2.0 mL.

[0213] The vial filling adapter 1100 may further include a vial filling assist assembly 1116 configured to fluidly couple, via a septum, an injectable fluid vial to a reservoir 908 of the disposable housing assembly 804. Referring particularly to FIG. 71, the vial filling assist assembly may include a double-ended needle assembly 1118. The double-ended needle assembly 1118 may include a first needle tip 1120 configured to penetrate a septum of a vial (not shown) and a second needle tip 1122 configured to penetrate a septum of the disposable housing assembly 804. As such, the vial and the reservoir 908 may be fluidly coupled, enabling the injectable fluid to be transferred from the vial to the reservoir 908. The double-ended needle assembly 1118 may include a vial engagement portion 1124 adjacent the first end 1120. The vial engagement arms 1124, 1126 may be configured to releasably engage, for example, a vial cap to assist in maintaining a fluid connection between the double-ended needle assembly 1118 and the vial. Additionally, the double-ended needle assembly 1118 may include a body 1128 slidably receivable within an opening 1130 of a vial filling assist body 1132. The vial filling assist body 1132 may include stabilizer arms 1134, 1136 configured to, for example, stabilize the vial during filling of the disposable housing assembly 804. In one embodiment, the vial may be engaged with the double-ended needle assembly 1118 such that, for example, the first end 1120 may penetrate the septum of the vial, and the vial cap may be engaged by the engagement arms 1124, 1126. The body 1128 may be slidably inserted into the opening 1130 such that the second end 1122 of the double-ended needle assembly 1118 may penetrate the septum of the disposable body assembly 804.

[0214] Similar to the filling adapter 1000, the vial filling assist assembly 1116 can be configured to be pivotally coupled to the vial filling adapter substrate 1138. For example, the vial filling assist 1116 may include pivot members 1140, 1142 that are configured to be received within pivot supports 1144, 1146 (shown, for example, in FIG. 71), thereby enabling the vial filling assist 1116 to pivot between an open position (such as shown in FIGS. 66 - 70) and a closed position (such as shown in FIGS. 72 - 74). The closed position may be suitable, for example, for packaging of the vial filling adapter 1100, storage of the vial filling adapter 1100, or the like. The vial filling adapter 1100 may include a support member 1148 to ensure that the vial filling assist 1116 is properly oriented for filling the reservoir 908. To properly orient the vial filling assist 1116, the user may pivot the vial filling assist 1116 to the fully open position, and the vial filling assist 1116 may contact the support member 1148. Additionally, the vial filling adapter substrate 1138 may include one or more locking features (such as locking tabs 1150, 1152) that may engage the vial filling assist 1116 and maintain the vial filling assist 1116 in the closed position. The vial filling adapter substrate 1138 may also include features (such as tabs 1154, 1156) that may be configured to assist in holding the double-ended needle assembly 1118, for example, by preventing proper separation of the double-ended needle assembly 1118 from the vial filling assist body 1132.

[0215] As shown in FIGS. 72 - 74, the filling assist assembly 1116 is in the closed position. In this configuration, the support member 1148 may additionally function as a needle guard. When removing the filling assist assembly 1116 from the disposable housing assembly 804, the support member 1148 may function to safely enable the user to firmly grip the end and rotate the filling assist assembly 1116 for removal. As shown in FIG. 70, in the open position, the support member 1148 may function as a stop to maintain proper orientation.

[0216] Referring again to FIGS. 57 - 73, an exemplary embodiment of the filling adapter includes gripping features (e.g., 1166 in FIG. 72). The gripping feature 1166 can provide a gripping interface for removing the filling adapter from the disposable housing assembly 804. As shown in one configuration of these figures, in other embodiments, the configuration can vary. In still other embodiments, the gripping feature may not be included.

[0217] According to one embodiment, the filling adapter substrate 1020 and the vial filling adapter substrate 1138 can be replaceable components. Thus, a single substrate (e.g., either the filling adapter substrate 1020 or the vial filling adapter substrate 1138) can be used with either the filling assistance 1010 or the vial filling assistance 1116. Thus, the number of individual components required for both filling adapters may be reduced, and the user may have the ability to select the filling adapter that may be most suitable for a given filling scenario.

[0218] Various embodiments of the filling adapter may provide many safety benefits including, but not limited to, providing a system for filling a reservoir without handling a needle, protecting the reservoir from unintentional contact with the needle, i.e., breaching the integrity of the reservoir through an unintentional puncture, and being designed to be used with both hands. In some embodiments, a system for maintaining air within the reservoir may be provided.

[0219] As discussed above, the reusable housing assembly 802 may include a battery 832, which may include, for example, a rechargeable battery. Referring also to FIGS. 75 - 80, the battery charger 1200 may be configured to recharge the battery 832. The battery charger 1200 may include a housing 1202 having a top plate 1204. The top plate 1204 may include one or more electrical contacts 1206 that are generally configured to be electrically coupled to the electrical contacts 834 of the reusable housing assembly 802. The electrical contacts 1206 may include, but are not limited to, electrical contact pads, spring - biased electrical contact members, or the like. Additionally, the top plate 1204 may include alignment tabs 1208, 1210 that are configured to engage the openings 836, 838 of the substrate 818 of the reusable housing assembly 802 (such as shown in FIG. 35C). The cooperation of the alignment tabs 1208, 1210 and the openings 836, 838 may ensure that the reusable housing assembly 802 is aligned with the battery charger 1200 such that the electrical contacts 1206 of the battery charger 1200 can be electrically coupled to the electrical contacts 834 of the reusable housing assembly 802.

[0220] Referring also to FIGS. 77 and 78, the battery charger 1200 may be configured to releasably engage the reusable housing assembly 802. For example, similar to the disposable housing assembly 804, the battery charger 1200 may include one or more locking tabs (such as the locking tabs 1212, 1214 shown in FIG. 76). The locking tabs (such as locking tabs 1212, 1214) may be engaged by the tabs 942, 944, 946, 948 of the locking ring assembly 806. As such, the reusable housing assembly 802 may be aligned with the battery charger 1200 (via the alignment tabs 1208, 1210) with the locking ring 806 in a first release position as shown in FIG. 77. The locking ring 806 may be rotated relative to the battery charger 1200 in the direction of arrow 1216 so that the tabs 942, 944, 946, 948 of the locking ring 806 are releasably engaged with the locking tabs (such as locking tabs 1212, 1214) of the battery charger 1200 as shown in FIG. 78.

[0221] In an embodiment, the battery charger 1200 may include a recessed region 1218 that, for example, in an exemplary embodiment, provides a gap to house the pump and valve components of the reusable housing assembly 802. Referring also to FIGS. 79 and 80, the battery charger 1200 may provide a current to the electrical contacts 1206 (and thereby to the reusable housing assembly 802 via the electrical contacts 834) to recharge the battery 832 of the reusable housing assembly 802. In some embodiments, the current may not be provided to the electrical contacts 1206 when a signal indicating a fully engaged reusable housing is not provided. According to such embodiments, risks associated with short circuits (e.g., due to foreign objects contacting the electrical contacts 1206) and damage to the reusable housing assembly 802 (e.g., due to improper initial alignment between the electrical contacts 1206 and the electrical contacts 834) may be reduced. Additionally, when the battery charger is not charging the reusable housing assembly 802, the battery charger 1200 may not draw current unnecessarily.

[0222] Still referring to FIGS. 79 and 80, the battery charger 1200 may include a lower housing portion 1224 and a top plate 1204. A printed circuit board 1222 (which may include, for example, the electrical contacts 1206) may be disposed within a cavity that is included between the top plate 1204 and the lower housing portion 1224.

[0223] Referring also to FIGS. 81 - 89, various embodiments of the battery charger / docking station are shown. FIGS. 81 and 82 depict a desktop charger 1250 that includes a recess 1252 configured to engage and recharge a reusable housing assembly (e.g., reusable housing assembly 802). The reusable housing assembly may be placed within the recess 1252 and / or may be releasably engaged within the recess 1252 as discussed above. Additionally, the desktop charger 1250 may include a recess 1254 configured to engage a remote control assembly (e.g., remote control assembly 300). The recess 1254 may include, for example, a USB plug 1256 that may be configured to couple to the remote control assembly when the remote control assembly is disposed within the recess 1254. The USB plug 1256 may enable data transfer to / from the remote control assembly and charging of the remote control assembly. The desktop charger 1250 may also include a USB port 1258 (which may include, for example, a mini - USB port) that enables the desktop charger to receive power (e.g., for charging the reusable housing assembly and / or the remote control assembly). Additionally / alternatively, the USB port 1258 may be configured for data transfer to / from the remote control assembly and / or the reusable housing assembly, for example, by connection to a computer (not shown).

[0224] Referring to FIGS. 83A - 83B, similar to previous embodiments, the desktop charger 1260 may include a recess 1262 for engaging a reusable housing assembly (e.g., reusable housing assembly 1264). The desktop charger may also include a recess 1266 configured to receive a remote control assembly (e.g., remote control assembly 1268). One or more of the recesses 1262, 1266 may each include electrical and / or data connections configured to charge and / or transfer data to / from the reusable housing assembly 1262 and / or the remote control assembly 1268.

[0225] Referring to FIGS. 84A - 84B, another embodiment of a desktop charger is shown. Similar to desktop charger 1260, desktop charger 1270 may each include a recess (not shown) for engaging a reusable housing assembly 1272 and a remote control assembly 1274. As shown, desktop charger 1270 may carry the reusable housing assembly 1272 and the remote control assembly 1274 in a parallel configuration. Desktop charger 1270 may include various electrical and data connections configured to charge and / or transfer data to / from the reusable housing assembly 1272 and / or the remote control assembly 1274 as described in the various embodiments above.

[0226] Referring to FIGS. 85A - 85D, foldable charger 1280 may include a recess 1282 for receiving a reusable housing assembly 1284 and a remote control assembly 1286. Foldable charger 1280 may include various electrical and data connections configured to charge and / or transfer data to / from the reusable housing assembly 1284 and / or the remote control assembly 1286 as described in the various embodiments above. Additionally, as shown in FIGS. 85B - 85D, foldable charger 1280 may include a pivotable cover 1288. The pivotable cover 1288 may be configured to pivot between an open position (e.g., as shown in FIG. 85B) where the reusable housing assembly 1284 and the remote control assembly 1286 may be docked to the foldable charger 1280 and a closed position (e.g., as shown in FIG. 85D) where the recess 1282 may be covered by the pivotable cover 1288. In the closed position, the recess 1282, as well as any electrical and / or data connections disposed therein, may be protected from damage.

[0227] Referring to FIG. 86, the wall charger 1290 may include a recess 1292 configured to receive a reusable housing assembly 1294. Additionally, the wall charger 1290 may include a recess 1296 configured to receive a remote control assembly 1298. The reusable housing assembly 1294 and the remote control assembly 1298 may be positioned in a stacked configuration, for example, thereby providing a relatively thin profile. The rear portion of the wall charger 1290 may include an electrical plug configured to enable the wall charger to be plugged into an electrical receptacle. As such, the wall charger 1290 may achieve a wall-mounted configuration while plugged into the electrical receptacle. Additionally, while plugged into the electrical receptacle, power may be provided to the reusable housing assembly 1294 and / or the remote control assembly 1298 for charging the wall charger 1290.

[0228] Referring to FIG. 87, the wall charger 1300 may include a recess 1302 configured to receive a remote control assembly 1304. Additionally, the wall charger may include a recess (not shown) configured to receive a reusable housing assembly 1306. The wall charger 1300 may be configured to position the remote control assembly 1304 and the reusable housing assembly 1306 in an antiparallel configuration that may provide a relatively thin profile. Additionally, the wall charger 1300 may include an electrical plug 1308 configured to be plugged into an electrical receptacle. The electrical plug 1308 may include a retractable configuration in which the electrical plug 1308 may be pivotable between a deployed position (e.g., as shown) and a retracted position. In the deployed position, the electrical plug 1308 may be oriented to be plugged into the electrical receptacle. In the retracted position, the electrical plug 1308 may be disposed within a recess 1310 that may protect the electrical plug 1308 from damage and / or from damaging other items.

[0229] Referring to FIG. 88, charger 1320 may include a recess 1322 configured to receive a reusable housing assembly 1324. Charger 1320 may additionally include a recess (not shown) configured to receive a remote control assembly 1326. Charger 1320 may additionally include a cover 1328. Cover 1328 may be configured to pivot between an open position (not shown) and a closed position. When cover 1328 is in the open position, the reusable housing assembly 1324 and the remote control assembly 1326 may be accessible (e.g., allowing a user to remove / install the reusable housing assembly 1324 and / or the remote control assembly 1326 from / into charger 1320). When cover 1324 is in the closed position, cover 1328 and charger body 1330 may substantially enclose the reusable housing assembly 1324 and / or the remote control assembly 1326 and / or the recess 1322, the recess being configured to receive the remote control assembly 1326, thereby providing protection against damage and / or tampering to the reusable housing assembly 1324, the remote control assembly 1326, and / or any electrical and / or data connections associated with charger 1320.

[0230] Referring to FIGS. 89A - 89B, the wall charger 1350 may include a recess 1352 configured to receive a remote control assembly 1354. The wall charger 1350 may also include a recess 1356 configured to receive a reusable housing assembly 1358. The wall charger 1350 may be configured to position the remote control assembly 1354 and the reusable housing assembly 1358 in a substantially parallel configuration, thereby providing a relatively thin profile. The charger 1350 may additionally include an electrical plug 1360 that may be configured, for example, to be inserted into an electrical receptacle. The electrical plug 1360 may include a retractable configuration such that the electrical plug 1360 may be pivotable between a deployed position (e.g., as shown) and a retracted position. In the deployed position, the electrical plug 1360 may be oriented to be inserted into an electrical receptacle. In the retracted position, the electrical plug 1360 may be disposed within a recess 1362 that may protect the electrical plug 1308 from damage and / or from damaging other items.

[0231] Infusion pump therapy may include volume and time specifications. The amount of fluid dispensed along with the dispensing timing may be two important factors of infusion pump therapy. As discussed in detail below, the infusion pump devices and systems described herein may provide a method of dispensing fluid, along with devices, systems, and methods for measuring the amount of fluid dispensed. However, in situations where calibration and accuracy of the measurement device are important, there may be an advantage in determining a degradation in the accuracy of the measurement device as soon as possible. Thus, there are advantages in off - board verification of volume and delivery.

[0232] As discussed above, the infusion pump assembly 100 may include a volume sensor assembly 148 configured to monitor the amount of fluid infused by the infusion pump assembly 100. Further, as discussed above, the infusion pump assembly 100 may be configured such that volume measurements generated by the volume sensor assembly 148 may be used through a feedback loop to control the amount of injectable fluid infused to the user.

[0233] Referring also to FIGS. 90A - 90C, one diagram and two cross - sectional views of the capacitive sensor assembly 148 are shown. Referring also to FIGS. 91A - 91I, various isometric views and diagrams of the capacitive sensor assembly 148 (which is shown to include the upper housing 1400) are shown. Referring also to FIGS. 92A - 92I, various isometric views and diagrams of the capacitive sensor assembly 148 (with the upper housing 1400 removed) are shown, exposing the speaker assembly 622, the reference microphone 626, and the printed circuit board assembly 830. Referring also to FIGS. 93A - 93I, various isometric views and diagrams of the capacitive sensor assembly 148 (with the printed circuit board assembly 830 removed) are shown, exposing the port assembly 624. Referring also to FIGS. 94A - 94F, various isometric views and cross - sectional diagrams of the capacitive sensor assembly 148 (with the printed circuit board assembly 830 removed) are shown, exposing the port assembly 624. Referring also to FIG. 95, an exploded view of the capacitive sensor assembly 148 is shown, exposing the upper housing 1400, the speaker assembly 622, the reference microphone 626, the seal assembly 1404, the lower housing 1402, the port assembly 624, the spring diaphragm 628, and the retaining ring assembly 1406.

[0234] The following discussion pertains to the design and operation of the capacitive sensor assembly 148 (shown in simplified form in FIG. 96). For the following discussion, the following names may be used.

[0235] [Table 5] (Derivation of the equation for the capacitive sensor assembly 148:) (Modeling of acoustic capacitance) The pressure and volume of an ideal adiabatic gas can be related as follows.

[0236] [Number] Here, K is a constant defined by the initial conditions of the system.

[0237] Equation 1 can be described as follows with respect to the average pressure P and volume V, and in addition to these, slight time-dependent disturbances p(t) and v(t).

[0238]

Number

[0239]

Number

[0240]

Number

[0241] When the sound pressure level is much smaller than the atmospheric pressure, the equation can be further simplified to the following equation

[0242]

Number

[0243] How valid this assumption is. It can be shown as follows using the adiabatic relation

[0244]

Number

[0245] Therefore, the error in the assumption is

[0246]

Number

[0247] A very large acoustic signal (120 dB) can correspond to a pressure sine wave with an amplitude of about 20 Pascals. Assuming air under atmospheric conditions (γ = 1.4, P = 101325 Pa), the resulting error is 0.03%. The conversion from dB to Pa is

[0248]

Number

[0249] Applying the ideal gas law P = ρRT and substituting into the pressure gives the following equation

[0250]

Number

[0251] Equation 9 can be described as the speed of sound

[0252]

Chemistry

[0253]

Number

[0254] The acoustic impedance with respect to the volume is as follows

[0255] [Mathematics] can be defined.

[0256] (Modeling of the acoustic port) The acoustic port can be modeled assuming that all of the fluid in the port moves essentially when the rigid cylinder reciprocates axially. It is assumed that all of the fluid in the channel moves at the same velocity, that the channel has a constant cross-section, and that the "end effect" due to the fluid entering and leaving the channel is ignored.

[0257] Equation

[0258] [Chemistry] When assuming laminar flow friction of, the frictional force acting on the mass of the fluid in the channel is as follows

[0259] [Mathematics] can be described as.

[0260] Next, for the dynamics of the fluid in the channel, a second-order differential equation can be described as follows

[0261] [Mathematics] or, for the volumetric flow rate, as follows

[0262] [Mathematics] seems to be.

[0263] Next, the acoustic impedance of the channel can be described as follows

[0264]

Number

[0265] (System transfer function) Using the capacitance and port dynamics defined above, the capacitance sensor assembly 148 has the following set of equations

[0266]

Number

[0267]

Number

[0268] If p0 is

[0269]

Chemistry

[0270]

Number

[0271] (Inter-system transfer function) The relationship between the speaker volume and the variable capacitance can be called the inter-system transfer function. This transfer function is derived from the above equation and

[0272] [Number] can be obtained.

[0273] Referring also to FIG. 97, the board diagram of Equation 23 is shown.

[0274] The difficulty with this relationship is that the complex poles depend on the variable capacitance V2 and the reference capacitance V1. A change in the average position of the speaker may result in an error in the estimated capacitance.

[0275] (Transfer function between ports) The relationship between the two capacitances on both sides of the acoustic port can be called the transfer function between ports. This relationship is

[0276] [Number] and is shown graphically in FIG. 98.

[0277] This relationship has the advantage that the poles depend only on the variable capacitance and not on the reference capacitance. However, there is a difficulty in that the resonance peak actually results from the inversion of the zero point according to the reference capacitance pressure. Therefore, the measured pressure value in the reference chamber has a low amplitude near resonance and potentially increases the noise of the measured value.

[0278] (Transfer function between speakers) The pressure can also be measured from both sides of the speaker. This is called the transfer function between speakers shown below,

[0279] [Number] and is shown graphically in FIG. 99.

[0280] In addition to a set of complex poles, this transfer function has a set of complex zeros.

[0281] Looking at the limit of this transfer function,

[0282]

Chem.

[0283]

Chem.

[0284] (Resonant Q factor and peak response) The quality of resonance is the ratio of the stored energy to the power loss that can be increased by the resonance frequency. For a pure second-order system, the Q factor can be expressed as a function of the damping ratio.

[0285]

Math.

[0286]

Math.

[0287] This is the damped natural frequency

[0288]

Math.

[0289] (Capacitance estimation) (Capacitance Estimation Using Phase between Ports) The variable capacitance (i.e., within the capacitance sensor chamber 620) can also be estimated using the phase between ports. The transfer function of the pressure ratio across the resonant ports is

[0290] [Number] and can be

[0291] At the 90° phase point, ω = ω n and 、 where

[0292] [Chemistry] is

[0293] The resonant frequency can be determined in a physical system using several methods. To find the 90° phase point, a phase-locked loop may be employed, and this frequency may correspond to the natural frequency of the system. Alternatively, the resonant frequency can be calculated using the phase at any two frequencies.

[0294] The phase φ at a given frequency satisfies the following relational expression

[0295] [Number] and is satisfied.

[0296] The solution for V2 is given by the following equation

[0297] [Number] and is given by

[0298] Therefore, the natural period of the system can be calculated using the ratio of the phases at two different frequencies ω1 and ω2.

[0299]

Number

[0300] For computational efficiency, it is not actually necessary to calculate the phase. The real and imaginary parts of the response (tan φ) are sufficient.

[0301] Rewriting Equation 33 for the variable capacitance gives the following equation

[0302]

Number

[0303] (Capacitance Estimation Using a Swept Sine Wave) The resonant frequency of the system can be estimated using swept sine wave system identification. In this method, the response of the system to a sinusoidal pressure fluctuation can be determined at a number of different frequencies. This frequency response data can then be used to estimate the system transfer function using linear regression.

[0304] The transfer function of the system can be expressed as a rational function of s. The general case is expressed as follows for a transfer function with an nth order numerator and an mth order denominator. N and D are the coefficients of the numerator and denominator, respectively. The equation is normalized as described above so that the leading coefficient of the denominator is 1.

[0305]

Number

[0306] This equation is

[0307] [Number] can be rewritten as.

[0308] When this sum is represented in matrix notation,

[0309] [Number] is obtained, where k is the number of data points collected in the swept sine wave. For the sake of simplicity of notation, this equation can be summarized using vectors,

[0310] [Number] where y is k×1, x is k×(m + n - 1), and c is (m + n - 1)×1. Then, the coefficients can be obtained using the least squares method. The error function is,

[0311] [Number] can be described as.

[0312] The function to be minimized is the weighted square of the error function, and W is a k×k diagonal matrix.

[0313] [Number] Since the two middle terms are scalars, the transpose is ignored and

[0314] [Number] to obtain.

[0315] In all of these cases, it may be necessary to use complex conjugation. This approach can result in complex coefficients, but the procedure can be modified to ensure that all coefficients are real. The least squares minimization can be modified to yield only real coefficients when the error function is changed to the following equation

[0316]

Number

[0317] Thus, the coefficients can be obtained by the following relational expression

[0318]

Number

[0319] (Solution of the second-order system) Transfer function

[0320]

Number

[0321] The coefficients of this transfer function are

[0322]

Number

[0323]

Number

[0324] To simplify the algorithm, some of the terms can be combined, and

[0325]

Number

[0326] To find the equation of D with respect to the complex response vector G and the natural frequency s = jω, X can be separated into its real and imaginary parts

[0327]

Number

[0328] Then, the real and imaginary parts of the equation of D can be

[0329]

Number

[0330] By combining these terms, the final equation of the D matrix that may contain only real values

[0331]

Number

[0332] The same approach can be taken to find the equation of the b vector with respect to G and ω. The real and imaginary parts of y are

[0333]

Number

[0334] By combining the real part and the imaginary part,

[0335]

Number

[0336] The next step is to invert the D matrix. Since the matrix is symmetric and positive definite, the number of calculations required to find the inverse is reduced from the general 3×3 case. The general formula for the inverse matrix is,

[0337]

Number

[0338] If D is

[0339]

Number

[0340]

Number

[0341] Due to symmetry, only the upper triangular matrix may need to be calculated.

[0342] Next, using the zero elements in the original array,

[0343]

Number

[0344] Finally, the inverse of D is

[0345]

Mathematics

[0346] The following equation

[0347]

Mathematics

[0348]

Mathematics

[0349] The final step is to obtain a quantitative assessment of how well the data fits the model. Therefore, the original equation for the error is

[0350]

Mathematics

[0351] This can be expressed as

[0352]

Mathematics

[0353] The model fitting error can be utilized to detect sensor failures.

[0354] (Alternative solution for second-order systems)

[0355] [Math] This equation can be rewritten as follows.

[0356] [Math] By putting this sum into matrix notation,

[0357] [Math] we obtain.

[0358] Transfer function

[0359] [Math] Consider a system with a zero-order numerator and a second-order denominator as shown by.

[0360] The coefficients of this transfer function can be obtained based on the equations

[0361] [Math] obtained in the previous section.

[0362] To simplify the algorithm,

[0363] [Math] Some terms can be combined as follows.

[0364] To obtain the expression for D with respect to the complex response vector G and the natural frequency s = jω, X is

[0365]

Number

[0366]

Number

[0367] Next, the real and imaginary parts of the expression for D are

[0368]

Number

[0369] By combining these terms, the final expression for the D matrix that can contain only real values

[0370]

Number

[0371] The same method can be taken to obtain the expression for the b vector with respect to G and ω. The real and imaginary parts of y are

[0372]

Number

[0373] By combining the real part and the imaginary part,

[0374] [Number] the equation of the b vector is obtained as follows.

[0375] (Implementation of acoustic capacitance sensing) (Collection of frequency response data and calculation of complex response) To implement the capacitance sensor assembly 148, the capacitance sensor assembly 148 should determine the relative response of the reference microphone 626 and the fixed capacitance microphone 630 to the sound wave set by the speaker assembly 622. This can be achieved by driving the speaker assembly 622 with a sine wave output at a known frequency. Then, the complex responses of the microphones 626, 630 can be found at that driving frequency. Finally, the relative response of the microphones 626, 630 is found and may be corrected for alternating sampling, for example, by an analog-to-digital converter (i.e., ADC).

[0376] In addition, the overall signal variance is calculated and compared to the variance of the pure tone extracted using the discrete Fourier transform (i.e., DFT). This can provide a measure of how much of the signal power is due to noise sources or distortion. This value may then be used to reject bad measurements and repeat.

[0377] (Calculation of discrete Fourier transform) The signal from the microphone can be sampled in synchronization with the output to the speaker assembly 622 such that a fixed number N of points are taken per wavelength. The measured signal at each point of the wavelength is summed over an integer number M of wavelengths and stored in the array x by the ISR for processing after all the data for that frequency has been collected.

[0378] The DFT can be performed on the data at integer values corresponding to the driving frequency of the speaker. The general formula for the first harmonic of the DFT is

[0379] [Number] where

[0380] The product MN is the total number of points, and the coefficient 2 is added as follows so that the real and imaginary parts resulting from the solution match the amplitude of the sine wave

[0381] [Number] and can be added.

[0382] The real part of this equation is

[0383] [Number] and can be

[0384] To reduce the number of calculations required to compute the DFT, the symmetry of the cosine function can be utilized. The above equation can be equivalent to the following equation

[0385] [Number] and can be

[0386] Similarly, for the imaginary part of the equation,

[0387] [Number] and can be, which is as follows

[0388]

Number

[0389] The variance of this signal is

[0390]

Number

[0391] The maximum possible values of the real and imaginary parts of x can be 2 11 which corresponds to half of the AD range. The maximum value of the sound variance can be half of the square of the AD range, i.e., 2 21 can be

[0392] (Calculation of signal variance) The pseudo-variance of the signal is given by the following relational expression

[0393]

Number

[0394] The result can be in units of the square of the AD count. Since the signal is averaged over M periods before the variance is calculated for N samples in the "average" period, this can be just a "pseudo-variance". However, this can be a useful measure for finding out whether the "average" signal looks like a sine wave at the expected frequency. This can be done by comparing the overall signal variance with the variance of the sine wave found by discrete Fourier transform.

[0395] The sum is for a 12-bit ADC

[0396]

Chemistry

[0397]

Chemical formula

[0398] (Calculation of relative microphone response) The relative responses (G) of microphones 626 and 630 are

[0399]

Mathematical formula

[0400] The denominator of either equation can be expressed in terms of the reference sound variance calculated in the previous section as follows.

[0401]

Mathematical formula

[0402] (Correction of A / D skew) The signals from microphones 626 and 630 do not have to be sampled simultaneously. That is, the A / D ISR obtains a total of N samples for each wavelength for microphones 626 and 630, and alternates between microphones 626 and 630. The result may be a phase offset between the two microphones 626 and 630 of π / N. To correct this phase offset, complex rotation can be applied to the relative frequency response calculated in the previous section as follows:

[0403] [Number] and can be applied to the relative frequency response calculated in the previous section.

[0404] (Reference model) (Second and higher order models) Leaks through the seal of the capacitive sensor chamber 620 (e.g., seal assembly 1404) can be modeled as a second resonant port (e.g., port 1504, Figure 100) connected to an external capacitance (e.g., external capacitance 1506, Figure 100).

[0405] The equations representing the three-chamber configuration can be

[0406] [Number] and can be obtained by substituting these equations into the state space, and its frequency response can be represented by the graph of the board diagram shown in Figure 101 and also in the form of a transfer function

[0407] [Number] and can be obtained, and its frequency response can be represented by the graph of the board diagram shown in Figure 101 and also in the form of a transfer function

[0408] [Number] It can be described by

[0409] By expanding the denominator, the following equation

[0410]

Number

[0411] The bubbles under the diaphragm material in the variable capacitance follow the same dynamic equation as the leakage path. In this case, the diaphragm material can play the role of the resonant mass rather than the leakage port. Therefore, the equation may be as follows.

[0412]

Number

[0413]

Number

[0414]

Number

[0415] (Second order with time delay) The equation for the capacitance sensor assembly 148 derived above assumes that the pressure is the same at any location within the acoustic capacitance. This is only an approximate equation because there is a time delay associated with the propagation of sound waves through the capacitance. This situation may appear as a time delay or time advance based on the relative positions of the microphone and the speaker.

[0416] The time delay is

[0417]

Number

[0418]

Number

[0419] (3 - Chamber Capacitance Estimation) The capacitance sensor assembly 148 can also be configured using a third reference capacitance (e.g., reference capacitance 1508, Figure 103) connected to a separate resonance port (e.g., port 1510, Figure 103). This configuration can enable temperature - independent capacitance estimation.

[0420] The set of equations representing the 3 - chamber configuration is

[0421]

Number

[0422] By using these equations and obtaining the values of the transfer function across each of the resonance ports, the following equation

[0423]

Number

[0424]

Number

[0425]

Number

[0426] The capacitance of the capacitance sensor chamber 620 may be estimated as follows:

[0427]

Number

[0428] Equation 120 illustrates that the capacitance of the capacitance sensor chamber 620 may be proportional to the reference capacitance 1508. The ratio of these two capacitances (in the ideal model) may depend only on the shape of the resonance port (e.g., port 1510, FIG. 103) and not on the temperature.

[0429] (Exponential capacitance model) The flow exiting through the flow resistance has the following form

[0430]

Number

[0431] Assuming a fixed input flow rate from the pump chamber, the capacitance of the capacitance sensor chamber 620 is given by the following differential equation

[0432]

Number

[0433] This is the following solution assuming an initial zero capacity

[0434]

Number

[0435] Therefore, the output flow rate is

[0436]

Number

[0437] The volume delivered into the pump phase is

[0438]

Number

[0439] (Device Calibration) Model fitting enables the resonant frequency of the port to be extracted from the sine sweep data. The next step is to relate this value to the delivery volume. The ideal relationship between the resonant frequency and the delivery volume is

[0440]

Number

[0441] Since the speed of sound varies with temperature, the temperature effect

[0442]

Number

[0443] The capacitance can then be expressed as a function of the measured resonance frequency and temperature

[0444]

Number

[0445]

Chemistry

[0446] (Implementation details) (End effects) The air resonating within the port (e.g., port assembly 624) can extend into the acoustic capacitance at the ends of each vibration. The distance that the air extends can be estimated based on the basic capacitance sensor assembly formula. For a given acoustic capacitance, the distance that the air extends into the capacitance can be expressed as a function of pressure and port cross-sectional area

[0447]

Number

[0448] Assuming the following values

[0449]

Number

[0450] (Sizing of V1 (i.e., fixed capacitance) relative to V2 (i.e., variable capacitance)) Sizing of V1 (e.g., fixed capacitance 1500) may require a trade-off between the relative positions of poles and zeros in the transfer function and the acoustic capacitance. The transfer functions of both V1 and V2 (e.g., variable capacitance 1502) are with respect to the capacitance displacement of the speaker assembly 622,

[0451]

Number

[0452] As V1 is increased, the gain may decrease and the speaker may be driven at a higher amplitude to obtain the same sound pressure level. However, increasing V1 may have the benefit of moving the complex zero in the p1 transfer function towards the complex pole. In the limiting case where V1→∞ and α→1, there is pole-zero cancellation and a flat response. Thus, increasing V1 can reduce both resonance and notch in the p1 transfer function, and n may have the benefit of moving the p2 pole towards ω, resulting in low sensitivity to measurement errors when calculating the p2 / p1 transfer function.

[0453] FIG. 104 is a graphical representation of the following equation

[0454]

Number

[0455] FIG. 105 is a graphical representation of the following equation

[0456]

Number

[0457] (Aliasing) Relatively high frequencies can alias down to the frequency of interest, and the aliased frequency is

[0458]

Number

[0459] The demodulation routine can effectively remove noise except for specific frequencies of demodulation. When the sample frequency is dynamically set to be a fixed multiple of the demodulation frequency, the noise frequencies that can alias down to the demodulation frequency can be a fixed set of harmonics of its fundamental frequency.

[0460] For example, when the sampling frequency is 8 times the demodulation frequency, the noise frequencies that can alias down to that frequency are

[0461]

Number

[0462]

Chemistry

[0463]

Number

[0464] (Performance) (Sensitivity to temperature) The sensitivity to temperature can be divided into gain change and noise change. When the temperature deviates by a factor of dT, the resulting gain error is given by the following equation

[0465] [Number] can be.

[0466] Therefore, if the same temperature is used for both sine wave sweeps, the error in temperature measurement

[0467] [Number] may appear to be a gain change to the system.

[0468] Therefore, for a temperature error of 1°K, the resulting capacitance error can be 0.3% at 298°K. This error can include both the error of the temperature sensor and the difference between the sensor temperature and the temperature of the air within the capacitance sensor assembly 148.

[0469] However, the measurement may be more susceptible to the effects of temperature measurement noise. The temperature change during differential sine wave sweep results in an error

[0470] [Number] that may appear more like an offset rather than a gain change.

[0471] Thus, if the measured value varies by 0.1 K during two measurement sine wave sweeps, the difference can be 0.012 μL. Thus, it may be more effective to use a consistent temperature estimate for each delivery rather than performing separate temperature measurements for each sine wave sweep (as shown in FIG. 107).

[0472] The LM73 temperature sensor can have a published accuracy of + / - 1°C and a resolution of 0.03°C. Further, the LM73 temperature sensor appears to consistently have a startup transient of approximately 0.3°C that requires approximately five sine wave sweeps to level out (as shown in FIG. 108).

[0473] The injection pump assemblies described above (e.g., injection pump assemblies 100, 100’, 400, 500) provide discrete delivery of injectable fluid, so the injection pump assemblies may be globally modeled in discrete regions (in the manner shown in FIG. 109), which is summarized by the following equation

[0474]

Equation

[0475] The discrete-time PI controller can function according to the following equation

[0476]

Equation

[0477] The AVS system described above functions by comparing the acoustic responses at the fixed capacitance 1500 and the variable capacitance 1502 with the speaker drive input and extracting the capacitance of the variable capacitance 1502. In this way, there are microphones (e.g., microphones 626, 630) in contact with each of these separate capacitances. In a more holistic manner, the response of the variable capacitance microphone 630 can also be used to detect the presence or absence of the disposable housing assembly 114. Specifically, if the disposable housing assembly 114 is not attached to (i.e., not positioned adjacent to) the variable capacitance 1502, the acoustic response to the speaker drive input should not be substantially sensed at all. However, the response of the fixed capacitance 1500 should still remain related to the speaker input. Thus, simply by ensuring that both microphones exhibit an acoustic response, microphone data can be used to determine whether the disposable housing assembly 114 is attached. If the microphone 626 (i.e., the microphone positioned adjacent to the fixed capacitance 1500) exhibits an acoustic response and the microphone 630 (i.e., the microphone positioned adjacent to the variable capacitance 1502) does not exhibit an acoustic response, it can be reasonably inferred that the disposable housing assembly 114 is not attached to the reusable housing assembly 102. Note that a failure of the variable capacitance microphone 630 may result in measured values in the midrange region that are nearly indistinguishable from the microphone response expected when the disposable housing assembly 114 is not attached, so a failure of the variable capacitance microphone 630 may also indicate the absence of the disposable housing assembly 114.

[0478] For the following discussion, the names described in the following table

[0479]

Table 6

[0480] As part of the demodulation routine employed in each frequency response calculation, the minimum and maximum measured values of both the fixed capacitance microphone 626 and the variable capacitance microphone 630 can be calculated. The sum of these maximum and minimum values is, for both the microphone 626 and the microphone 630, over the entire sine wave sweep (as discussed above),

[0481] [Number] calculated as such, and the difference between these two sums is,

[0482] [Number] simplified as such.

[0483] δ can be divided by the number of sine wave sweeps to obtain the average minimum / maximum difference of the sine wave sweep (which is then compared to a threshold value), and the threshold value can be equivalently multiplied by N for computational efficiency. Thus, the basic available detection algorithm is,

[0484] [Number] defined as such.

[0485] The additional condition that the maximum / minimum difference is greater than the threshold value is a check performed to ensure that a malfunctioning speaker is not the cause of the received acoustic response. This algorithm may be repeated for any sine wave sweep, and thus, for example, enables the detection of the detachment of the disposable housing assembly 114 (i.e., in the worst-case scenario where the disposable housing assembly 114 is removed in the second half of an ongoing sine wave sweep) within at most two consecutive sweeps.

[0486] Thresholding for the above algorithm may be based entirely on numerical evidence. For example, an investigation of the typical minimum / maximum response difference may show that none of the individual differences are less than 500 ADC counts. Thus, all data investigated while the disposable housing assembly 114 is detached from the reusable housing assembly 102 may show all minimum / maximum response differences as being sufficiently less than 500 ADC counts. Thus, the threshold for δ may be set at T = 500.

[0487] The capacitance sensor assembly 148 has been described above as being utilized within an injection pump assembly (e.g., injection pump assembly 100), but other configurations are possible and are considered to be within the scope of the present disclosure, so this is for illustrative purposes only and is not intended to be limiting of the present disclosure. For example, the capacitance sensor assembly 148 may be used in a process control environment, for example, to control the quantity of chemicals mixed together. Alternatively, the capacitance sensor assembly 148 may be used in a beverage dispensing system, for example, to control the quantity of raw materials mixed together.

[0488] The capacitance sensor assembly 148 has been described above as utilizing a port (e.g., port assembly 624) as a resonator, but other configurations are possible and are considered to be within the scope of the present disclosure, so this is for illustrative purposes only. For example, a solid mass (not shown) may be suspended within the port assembly 624 to function as a resonator for the capacitance sensor assembly 148. Specifically, a mass for the resonator (not shown) may be suspended on a diaphragm (not shown) that traverses the port assembly 624. Alternatively, the diaphragm itself (not shown) may serve the role of the mass for the resonator. The natural frequency of the capacitance sensor assembly 148 may be a function of the capacitance of the variable capacitor 1502. Thus, if the natural frequency of the capacitance sensor assembly 148 can be measured, the capacitance of the variable capacitor 1502 can be calculated.

[0489] The natural frequency of the capacitance sensor assembly 148 can be measured in a number of different ways. For example, a time-varying force may be applied to a diaphragm (not shown), and the relationship between the force and the movement of the diaphragm (not shown) can be used to estimate the natural frequency of the capacitance sensor assembly 148. Alternatively, a mass (not shown) can be perturbed and then vibrated. The unforced movement of the mass (not shown) can then be used to calculate the natural frequency of the capacitance sensor assembly 148.

[0490] The force applied to the resonant mass (not shown) may be achieved in a variety of ways, examples of which are the following · A speaker assembly 622 can generate a time-varying pressure within a fixed volume 1500. · The resonant mass (not shown) can be a piezoelectric material that responds to a time-varying voltage / current. · The resonant mass (not shown) can be a voice coil that responds to a time-varying voltage / current. may include, but are not limited to, the following.

[0491] The force applied to the resonant mass may be measured in a variety of ways, examples of which are the following · Measure the pressure within a fixed volume. · The resonant mass (not shown) can be a piezoelectric material. · A strain gauge can be connected to a diaphragm (not shown), or to another structural member that supports the resonant mass (not shown). may include, but are not limited to, the following.

[0492] Similarly, the displacement of the resonant mass (not shown) can be estimated by measuring the pressure in a variable capacitance, or directly measured in a variety of ways, examples of which are the following · Via a piezoelectric sensor. · Via a capacitance sensor. · Via an optical sensor. · Via a Hall effect sensor. · Via a potentiometer (time-varying impedance) sensor. · Via an inductive sensor. ·Via a linear variable differential transformer (LVDT). May include, but is not limited to, them.

[0493] Furthermore, a resonant mass (not shown) can be integral with either a force-type sensor or a displacement-type sensor (i.e., the resonant mass (not shown) may be made of a piezoelectric material).

[0494] The application of force and the measurement of displacement can be achieved by a single device. For example, a piezoelectric material may be used for the resonant mass (not shown), and a time-varying voltage / current can be applied to the piezoelectric material to generate a time-varying force. The resulting voltage / current applied to the piezoelectric material can be measured, and the transfer function between the two can be used to estimate the natural frequency of the capacitive sensor assembly 148.

[0495] As discussed above, the resonant frequency of the capacitive sensor assembly 148 can be estimated using swept sine wave system identification. Specifically, the above model fitting may enable the resonant frequency of the port assembly to be extracted from the sine wave sweep data, which can then be used to determine the delivery capacitance. The ideal relationship between the resonant frequency and the delivery capacitance is as follows

[0496]

Number

[0497] Since the speed of sound varies with temperature, it can be useful to separate the temperature effect

[0498]

Number

[0499] Then, the capacitance, as a function of the measured resonant frequency and temperature, is as follows

[0500] [Number] can be expressed as follows, where c is a calibration constant

[0501] [Chemistry] is.

[0502] Next, the infusion pump assembly 100 can compare this calculated volume V2 (i.e., representing the actual volume of injectable fluid delivered to the user) with a target volume (i.e., representing the quantity of fluid that should have been delivered to the user). For example, assume that the infusion pump assembly 100 is configured to deliver a base dose of 0.100 units of injectable fluid to the user every 30 minutes. Further, assume that upon achieving such delivery, the volume sensor assembly 148 indicates a calculated volume V2 of 0.095 units of injectable fluid (i.e., representing the actual volume of injectable fluid delivered to the user).

[0503] When calculating the volume V2, the infusion pump assembly 100 may first determine the volume of fluid within the volume sensor chamber 620 prior to administration of a dose of injectable fluid, and may later determine the volume of fluid within the volume sensor chamber 620 after administration of a dose of injectable fluid. The difference between these two measurements indicates V2 (i.e., the actual volume of injectable fluid delivered to the user). Thus, V2 is a differential measurement.

[0504] V2 can be the total void across the diaphragm in the variable volume chamber. The actual fluid delivery to the patient can be the difference in V2 from when the chamber was full until after the measurement valve is opened and the chamber is emptied. V2 may not be the directly delivered volume. For example, the air volume may be measured and a series of differential measurements can be taken. For occlusion, an empty measurement may be taken, the chamber may be filled and a full measurement taken, and then an overall measurement can be obtained after the outlet valve is opened. Thus, the difference between the first measurement and the second measurement can be the amount delivered, and the difference between the second measurement and the third measurement can be the amount delivered to the patient.

[0505] Accordingly, the electrical control assembly 110 can determine that the delivered injectable fluid is 0.005 units less than the required amount. In response to this determination, the electrical control assembly 110 can provide an appropriate signal to the mechanical control assembly 104 so that any additional required dose can be delivered. Alternatively, the electrical control assembly 110 can provide an appropriate signal to the mechanical control assembly 104 so that an additional dose can be dispensed along with the next dose. Thus, during administration of the next 0.100 unit dose of injectable fluid, the output command to the pump can be modified based on the difference between the targeted and delivered amounts.

[0506] Referring also to FIG. 110, one particular implementation of a control system for controlling the amount of injectable fluid currently being injected is shown, at least in part, based on the amount of injectable fluid previously administered. Specifically, continuing with the above example, for illustrative purposes, assume that the electrical control assembly 110 requests delivery of a 0.100 unit dose of injectable fluid to the user. Thus, the electrical control assembly 110 may provide the target differential capacitance signal 1600 (identifying a partial base dose of 0.010 units of injectable fluid per cycle of the shape memory actuator 112) to the capacitance controller 1602. Thus, in this particular example, the shape memory actuator 112 may need to be cycled 10 times to achieve the desired base dose of 0.100 units of injectable fluid (i.e., 10 cycles × 0.010 units / cycle = 0.100 units). Next, the capacitance controller 1602 may provide an “on time” signal 1606 to the SMA (i.e., shape memory actuator) controller 1608. Also, a battery voltage signal 1610 is provided to the SMA controller 1608.

[0507] Specifically, the shape memory actuator 112 may be controlled by varying the amount of thermal energy (e.g., joules) applied to the shape memory actuator 112. Thus, if the voltage level of the battery 606 is reduced, the amount of joules applied to the shape memory actuator 112 may also be reduced over a defined period. Conversely, if the voltage level of the battery 606 is increased, the amount of joules applied to the shape memory actuator 112 may also be increased over a defined period. Thus, by monitoring the voltage level of the battery 606 (via the battery voltage signal 1610), the type of signal applied to the shape memory actuator 112 may be varied to ensure that an appropriate amount of thermal energy is applied to the shape memory actuator 112 regardless of the battery voltage level.

[0508] The SMA controller 1608 can process the "on-time" signal 1606 and the battery voltage signal 1610 to determine an appropriate SMA drive signal 1612 to apply to the shape memory actuator 112. An example of the SMA drive signal 1612 is a series of binary pulses where the amplitude of the SMA drive signal 1612 essentially controls the stroke length of the shape memory actuator 112 (and thus the pump assembly 106), and the duty cycle of the SMA drive signal 1612 essentially controls the stroke rate of the shape memory actuator 112 (and thus the pump assembly 106). Further, since the SMA drive signal 1612 indicates a differential capacitance (i.e., the capacitance injected during each cycle of the shape memory actuator 112), the SMA drive signal 1612 can be integrated by a discrete-time integrator 1614 to generate a capacitance signal 1616 that indicates the total amount of injectable fluid injected during a plurality of cycles of the shape memory actuator 112. For example, in order to inject 0.100 units of injectable fluid (as discussed above), it may take 10 cycles of the shape memory actuator 112 (at 0.010 units per cycle), so the discrete-time integrator 1614 can integrate the SMA drive signal 1612 over these 10 cycles to determine the total amount of injectable fluid injected (as represented by the capacitance signal 1616).

[0509] The SMA drive signal 1612 can, for example, over one cycle, actuate the pump assembly 106 and result in the filling of the capacitive sensor chamber 620 included within the capacitive sensor assembly 148. Next, the infusion pump assembly 100 may take a first measurement of the quantity of fluid included within the capacitive sensor chamber 620 (as discussed above). Further, as discussed above, the measurement valve assembly 610 may later be energized to deliver all or a portion of the fluid within the capacitive sensor chamber 620 to the user. Next, the infusion pump assembly 100 may take a measurement of the quantity of fluid included within the capacitive sensor chamber 620 (as described above) and use these two measurements to determine V2, i.e., the actual volume of injectable fluid delivered to the user during the current cycle of the shape memory actuator 112. Once determined, V2 (i.e., as represented by the signal 1618) may be provided (i.e., fed back) to the capacitance controller 1602 for comparison with the previously received target differential capacitance.

[0510] Continuing with the above example where the differential target capacitance was 0.010 units of injectable fluid, assume that V2 (i.e., as represented by the signal 1618) identifies 0.009 units of injectable fluid as having been delivered to the user. Accordingly, the infusion pump assembly 100 may increase the next differential target capacitance to 0.011 units to offset the previous 0.001 unit shortfall. Thus, as discussed above, the amplitude and / or duty cycle of the SMA drive signal 1612 may be increased when delivering the next basal dose of injectable fluid to the user. This process may be repeated over the remaining 9 cycles of the shape memory actuator 112 (as discussed above) and the discrete time integrator 1614 may integrate the SMA drive signal 1612 (to generate the capacitance signal 1616) which may define the total quantity of injectable fluid delivered to the user.

[0511] Referring also to FIG. 111, one possible embodiment of the volume controller 1602 is shown. In this particular implementation, the volume controller 1602 may include a PI (Proportional Integrator) controller 1650. The volume controller 1602 may include a feedforward controller 1652 for setting an initial “guess” regarding the “on-time” signal 1606. For example, for the situation described above where the target differential volume signal 1600 identifies a partial basal dose of 0.010 units of fluid injectable per cycle of the shape memory actuator 112, the feedforward controller 1652 may define, for example, an initial “on-time” of 1 millisecond. The feedforward controller 1652 may include, for example, a look-up table that defines an initial “on-time” based at least in part on the target differential volume signal 1600. The volume controller 1602 may further include a discrete-time integrator 1654 for integrating the target differential volume signal 1600 and a discrete-time integrator 1656 for integrating V2 (i.e., as represented by the signal 1618).

[0512] Referring also to FIG. 112, one possible embodiment of the feedforward controller 1652 is shown. In this particular implementation, the feedforward controller 1652 may define a constant signal 1658 and may include an amplifier 1660 (e.g., a unity-gain amplifier), the output of which may be summed with the constant signal 1658 at an adder node 1662. The resulting sum signal (i.e., signal 1664) may be provided as an input signal, for example, to a look-up table 1666, which may be processed to generate the output signal of the feedforward controller 1652.

[0513] As discussed above, the pump assembly 106 may be controlled by the shape memory actuator 112. Further, as discussed above, the SMA controller 1608 may process the “on-time” signal 1606 and the battery voltage signal 1610 to determine an appropriate SMA drive signal 1612 to apply to the shape memory actuator 112.

[0514] Referring also to FIGS. 113 - 114, one particular implementation of the SMA controller 1608 is shown. As discussed above, the SMA controller 1608 may respond to an “on - time” signal 1606 and a battery voltage signal 1610 and may provide an SMA drive signal 1612 to the shape memory actuator 112. The SMA controller 1608 may include a feedback loop (including a unit delay 1700), and its output may be multiplied by the battery voltage signal 1610 in a multiplier 1702. The output of the multiplier 1702 may be amplified, for example, by a unity - gain amplifier 1704. The output of the amplifier 1704 may be applied to the negative input of an adder node 1706 to which the “on - time” signal 1606 is applied. The output of the adder node 1706 may be amplified (e.g., via a unity - gain amplifier 1708). The SMA controller may also include a feed - forward controller 1710 (similar to the feed - forward controller 1652 of the capacitance controller 1602, see FIG. 112) to provide an initial value of the SMA drive signal 1612. The output of the feed - forward controller 1710 may be summed at an adder node 1712 with the output of the amplifier 1708 and an integral representation of the output of the amplifier 1708 (i.e., signal 1714) to form the SMA drive signal 1612.

[0515] The SMA drive signal 1612 may be provided to a control circuit that achieves the application of force to the shape memory actuator 112. For example, the SMA drive signal 1612 may be applied to a switching assembly 1716 that selectively applies a current signal 1718 (supplied from the battery 606) and / or a fixed signal 1720 to the shape memory actuator. For example, the SMA drive signal 1612 may achieve the application of energy (supplied from the battery 606 via the current signal 1718) through the switching assembly 1716 in a manner that achieves the duty cycle defined by the SMA drive signal 1612. A unit delay 1722 may generate a delayed version of the signal applied to the shape memory actuator 112 to form the battery voltage signal 1610 (which may be applied to the SMA controller 1608).

[0516] When applying power to the shape memory actuator 112, the voltage can be applied over a fixed time period in a) a fixed load cycle with an unregulated voltage, b) a fixed load cycle with a regulated voltage, c) a variable load cycle based on the measured current value, d) a variable load cycle based on the measured voltage value, and e) a variable load cycle based on the square of the measured voltage value. Alternatively, the voltage can be applied to the shape memory actuator 112 over a variable time period based on the measured impedance.

[0517] When applying an unregulated voltage over a fixed time period in a fixed load cycle, inner loop feedback may be used and the shape memory actuator can be driven in the fixed load cycle and at an on-time determined by an outer capacitive loop.

[0518] When applying a regulated voltage over a fixed time period in a fixed load cycle, inner loop feedback may not be used and the shape memory actuator 112 can be driven in the fixed load cycle and at an on-time determined by an outer capacitive loop.

[0519] When applying an unregulated voltage in a variable fixed load cycle based on the measured current value, the actual current applied to the shape memory actuator 112 may be measured and the load cycle can be adjusted during operation of the shape memory actuator 112 to maintain the correct average current.

[0520] When applying an unregulated voltage in a variable fixed load cycle based on the measured voltage value, the actual voltage applied to the shape memory actuator 112 may be measured and the load cycle can be adjusted during operation of the shape memory actuator 112 to maintain the correct average voltage.

[0521] In a variable duty cycle based on the square of the measured voltage value, when an unregulated voltage is applied, the actual voltage applied to the shape memory actuator 112 may be measured, and the duty cycle may be adjusted during operation of the shape memory actuator 112 to maintain the square of the voltage at a level necessary to provide a desired level of power to the shape memory actuator 112 (based on the impedance of the shape memory actuator 112).

[0522] Referring also to FIGS. 114A-114B, another implementation of the SMA controller 1608 is shown. Specifically, FIG. 114A is an electrical circuit diagram that may include a microprocessor and various control loops configured to provide a PWM signal that can open and close a switch assembly. The switch assembly may control the current that can flow through the shape memory actuator. The battery may provide current to the shape memory actuator. Further, 114B discloses a capacitance controller and an internal shape memory actuator controller. The shape memory actuator controller may provide a PWM signal to the pump, which may be modified based on the battery voltage. This may occur at a fixed on-time, and as a result, the capacitance may be measured by the capacitance sensor assembly 148 and fed back to the capacitance controller.

[0523] In a preferred embodiment, the load cycle is varied based on the measured battery voltage to provide substantially consistent power. The load cycle is adjusted to compensate for lower battery voltages. The battery voltage can change for two reasons: 1) as the battery discharges, the voltage slowly decreases, and 2) when a load is applied to the battery, the voltage gradually decreases due to internal impedance. This occurs in any system, and this is compensated for by adjusting the load cycle and thus reducing lower or fluctuating battery voltages. The battery voltage can be measured by a microprocessor. In other systems, 1) the voltage may be regulated (turn on a regulator to maintain the voltage at a stable voltage), and 2) the feedback may be based on something else (i.e., not necessarily measuring the battery voltage, such as the speed or position of a motor).

[0524] Other configurations can be utilized to control the shape memory actuator. For example, A) the shape memory actuator can be controlled in a fixed load cycle with an unregulated voltage. As the voltage varies, the reproducibility of heating the shape memory actuator is reduced. B) A fixed load cycle of a regulated voltage that compensates for changes in the battery voltage can be utilized. However, adjusting the voltage downward is not very energy efficient. C) The load cycle can be varied based on changes in current (this may require a more complex measurement circuit). D) The load cycle can be varied based on the measured voltage. E) The load cycle can be varied based on the square of the current or the square of the voltage divided by the resistance. F) The voltage can be applied for a variable amount of time based on the measured impedance (for example, an impedance can be measured using a Wheatstone gauge (not shown)). The impedance of the shape memory actuator can be correlated with strain (i.e., based on its impedance, the movement of the SMA can be correlated).

[0525] Referring to FIG. 115, as discussed above, to improve the safety of the infusion pump assembly 100, the electrical control assembly 110 may include two separate and distinct microprocessors, namely, a supervisor processor 1800 and a command processor 1802. Specifically, the command processor 1802 may perform the functions discussed above (e.g., generating the SMA drive signal 1612), and (in this embodiment) may control the relay / switch assemblies 1804, 1806 that control the functionality of the shape memory actuators 112, 632, respectively. The command processor 1802 may receive feedback from the signal conditioner 1808 regarding the state (e.g., voltage level) of the voltage signals applied to the shape memory actuators 112, 632. The supervisor processor 1800 may control the relay / switch assembly 1810 independently of the relay / switch assemblies 1804, 1806. Thus, when an infusion event is desired, both the supervisor processor 1800 and the command processor 1802 must agree that the infusion event is appropriate, and both must activate their respective relay / switches. If either the supervisor processor 1800 or the command processor 1802 is unable to activate its respective relay / switch, the infusion event will not occur. Thus, through the supervisor processor 1800 and the command processor 1802, and the coordination and concurrence that must occur, the safety of the infusion pump assembly 100 is improved.

[0526] The supervisor processor may prevent the command processor from delivering when it should not, and may issue a warning if the command processor fails to deliver when it should. The supervisor processor may place the relay / switch assembly in a deactivated state if the command processor activates the wrong switch or attempts to apply power for an excessive length of time.

[0527] The supervisor processor may redundantly calculate (i.e., double-check the calculations of the command processor) as to how much insulin should be delivered. The command processor may determine the delivery schedule, and the supervisor processor may redundantly check these calculations.

[0528] The supervisor may also redundantly hold a profile (delivery profile) in the RAM, so that even if the command processor is performing correct calculations, a faulty RAM may cause the commands to produce incorrect results. The supervisor uses, for example, a local copy of the base profile for double-checking.

[0529] The supervisor can double-check the AVS measurements, look at the AVS calculations, and apply safety checks. Double-checking is performed every time an AVS measurement is taken.

[0530] Referring also to FIG. 116, one or more of the supervisor processor 1800 and the command processor 1802 may perform diagnostics on various parts of the infusion pump assembly 100. For example, the voltage dividers 1812, 1814 may be configured to monitor voltages (V1 and V2, respectively) sensed at the distal end of, for example, the shape memory actuator 112. Knowing the signals applied to the relay / switch assemblies 1804, 1810, the values of the voltages V1 and V2 enable diagnostics to be performed on the various components of the circuit shown in FIG. 116 (similar to that shown in the exemplary diagnostic table 1816).

[0531] As discussed above, as illustrated in FIGS. 115-116, in order to improve the safety of the infusion pump assembly 100, the electrical control assembly 110 may include a plurality of microprocessors (e.g., a supervisor processor 1800 and a command processor 1802), each of which may be required to interact and operate simultaneously to achieve delivery of an injectable fluid dose. If the microprocessors are unable to interact / operate simultaneously, delivery of an injectable fluid dose may fail and one or more alarms may be induced, thus improving the safety and reliability of the infusion pump assembly 100.

[0532] A master alarm that tracks volume error over time may be utilized. Thus, if the total error becomes too large, the master alarm may be activated, indicating that there may be something abnormal with the system. Thus, the master alarm may indicate the total volume comparison being made and the discrepancies being noted. A typical value of the discrepancy required to activate the master alarm may be 1.00 milliliter. The master alarm may monitor the total in a leaky fashion (i.e., the inaccuracy has a time horizontal axis).

[0533] Referring also to FIGS. 117A-117B, one such exemplary embodiment of such an interaction among a plurality of microprocessors during delivery of a dose of injectable fluid is shown. Specifically, the command processor 1802 may first determine 1900 an initial volume of injectable fluid within the volume sensor chamber 620. The command processor 1802 may then provide 1902 a "pump power request" message to the supervisor processor 1800. Upon receiving 1904 the "pump power request" message, the supervisor processor 1800 may energize 1906, for example, the relay / switch 1810 (and thus energize the shape memory actuator 112), and may transmit 1908 a "pump power on" message to the command processor 1802. Upon receiving 1910 the "pump power on" message, the command processor 1802 may activate 1912, for example, the pump assembly 106 (by energizing the relay / switch 1804), during which time the supervisor processor 1800 may monitor 1914, for example, the operation of the pump assembly 106.

[0534] Once the operation of the pump assembly 106 is completed, the command processor 1802 may provide a "pump power off" message to the supervisor processor 1800 1914. Upon receiving the "pump power off" message 1916, the supervisor processor 1800 turns off the power of the relay / switch 1810 1918 and may provide a "pump power off" message to the command processor 1802 1920. Upon receiving the "pump power off" message 1922, the command processor 1802 may measure the quantity of injectable fluid delivered by the pump assembly 106 1924. This may be accomplished by measuring the current quantity of fluid in the volumetric sensor chamber 620 and comparing it with the quantity determined above (at step 1900). Once determined 1924, the command processor 1802 may provide a "valve opening power request" message to the supervisor processor 1800 1926. Upon receiving the "valve opening power request" message 1928, the supervisor processor 1800 may energize the relay / switch 1810 1930 (and thus energize the shape memory actuator 632), and may transmit a "valve opening power on" message to the command processor 1802 1932. Upon receiving the "valve opening power on" message 1934, the command processor 1802 may operate the measurement valve assembly 610 (by energizing the relay / switch 1806 for example) 1936, during which time the supervisor processor 1800 may monitor the operation of the measurement valve assembly 610 for example 1938.

[0535] Once the operation of the measurement valve assembly 610 is completed, the command processor 1802 may provide a "valve power off" message to the supervisor processor 1800 1940. Upon receiving the "valve power off" message 1942, the supervisor processor 1800 turns off the power of the relay / switch 1810 1944 and may provide a "valve power off" message to the command processor 1802 1946.

[0536] Upon receiving the "valve power off" message at 1948, the command processor 1802 may provide a "valve closure power request" message to the supervisor processor 1800 at 1950. Upon receiving the "valve closure power request" message at 1952, the supervisor processor 1800 may energize the relay / switch 1810 at 1954 (and thus energize the shape memory actuator 652), and may send a "power on" message to the command processor 1802 at 1956. Upon receiving the "power on" message at 1958, the command processor 1802 may activate a power relay / switch (not shown) configured to energize the shape memory actuator 652 at 1960, during which time the supervisor processor 1800 may monitor the operation of the shape memory actuator 652, for example, at 1962.

[0537] As discussed above (and with temporary reference to FIGS. 26A, 26B, 27A, 27B, and 28), the shape memory actuator 652 may be fixed to the first end using the electrical contact 654. The other end of the shape memory actuator 652 may be connected to the bracket assembly 656. When the shape memory actuator 652 is activated, the shape memory actuator 652 may pull the bracket assembly 656 forward and release the valve assembly 634. As such, the metering valve assembly 610 may be activated via the shape memory actuator 632. Once the metering valve assembly 610 is activated, the bracket assembly 656 may manually latch onto the valve assembly 610 in the activated position. By operating the shape memory actuator 652, the bracket assembly 656 may be pulled forward and the valve assembly 634 may be released. Assuming that the shape memory actuator 632 is no longer activated, once the bracket assembly 656 releases the valve assembly 634, the metering valve assembly 610 may come to a stop state. Thus, by operating the shape memory actuator 652, the metering valve assembly 610 may come to a stop state.

[0538] Once the operation of the shape memory actuator 652 is complete, the command processor 1802 may provide a "power off" message to the supervisor processor 1800 at 1964. Upon receiving the "power off" message at 1966, the supervisor processor 1800 turns off the power of the relay / switch 1810 at 1968 and may provide a "power off" message to the command processor 1802 at 1970. Upon receiving the "power off" message at 1972, the command processor 1802 may determine the amount of injectable fluid within the volume sensor chamber 620, and thus the command processor 1802 can compare this measured amount with the amount determined above (at step 1924) to enable determination of the amount of injectable fluid delivered to the user at 1974.

[0539] If the amount of injectable fluid delivered to the user at 1974 is less than the amount of injectable fluid specified for the basal / bolus injection event, the above procedure may be repeated (via loop 1976).

[0540] Referring to FIG. 118, another exemplary embodiment of the interaction between processors 1800 and 1802 during the scheduling of the dose of injectable fluid is shown. Command processor 1802 may monitor 2000, 2002 for receipt of (respectively) a base scheduling message or a bolus request message. Upon receipt of either of these messages 2000, 2002, command processor 1802 may set the desired delivery volume 2004 and provide a "delivery request" message to supervisor processor 1800 2006. Upon receipt of the "delivery request" message 2008, supervisor processor 1800 may verify the volume 2004 defined by command processor 1802 2010. Once verified 2010, supervisor processor 1800 may provide a "delivery approval" message to command processor 1802 2012. Upon receipt of the "delivery approval" message 2014, command processor 1802 may update the controller (e.g., the controller discussed above and illustrated in FIG. 110) 2016 and perform the delivery of the base / bolus dose of injectable fluid 2018. Command processor 1808 may monitor and update 2022 the total amount of injectable fluid delivered to the user (as discussed above and illustrated in FIGS. 117A-117B). Once the appropriate amount of injectable fluid has been delivered to the user, command processor 1802 may provide a "delivery complete" message to supervisor processor 1800 2024. Upon receipt of the "delivery complete" message 2026, supervisor processor 1800 may update the total amount of injectable fluid delivered to the user 2028. If the total amount of injectable fluid delivered to the user 2018 is less than the amount defined above (at step 2004), the injection process discussed above may be repeated (via loop 2030).

[0541] Referring also to FIG. 119, an embodiment of a manner in which supervisor processor 1800 and command processor 1802 may interact while achieving volume measurement via volume sensor assembly 148 (as described above) is shown.

[0542] Specifically, the command processor 1802 may initialize the volume sensor assembly 148 at 2050, begin collecting data from the volume sensor assembly 148 at 2052, and the process may be repeated for each frequency utilized in the sine wave sweep described above. Each time data is collected for a particular sweep frequency, a data point message may be provided from the command processor 1802 at 2054, which may be received by the supervisor processor 1800 at 2056.

[0543] Once data collection 2052 is complete for the entire sine wave sweep, the command processor 1802 may estimate the volume of injectable fluid delivered by the injection pump assembly 100 at 2058. The command processor 1802 may provide a volume estimate message to the supervisor processor 1800 at 2060. Upon receiving this volume estimate message at 2062, the supervisor processor 1800 may check (i.e., verify) the volume estimate message at 2064. Once checked (i.e., verified), the supervisor processor 1800 may provide a verification message to the command processor 1802 at 2066. Once received from the supervisor processor 1800 at 2068, the command processor 1802 may set the measurement state for the dose of injectable fluid delivered by the volume sensor assembly 148.

[0544] As discussed above and referring momentarily to FIG. 11), various embodiments of the infusion pump assemblies discussed above (e.g., infusion pump assemblies 100, 100', 400, 500) may be configured via a remote control assembly 300. When configurable via the remote control assembly 300, the infusion pump assembly may include a telemetry circuit (not shown) that enables communication (e.g., wired or wireless) between the infusion pump assembly and, for example, the remote control assembly 300, thus enabling the remote control assembly 300 to remotely control the infusion pump assembly. The remote control assembly 300 (which may similarly include a telemetry circuit (not shown) and may be capable of communicating with the infusion pump assembly) may include a display assembly 302 and an input assembly 304. The input assembly 304 may include a slider assembly 306 and switch assemblies 308, 310. In other embodiments, the input assembly may include a jog wheel, multiple switch assemblies, or the like. The remote control assembly 300 may enable a user to program basal and bolus delivery events.

[0545] The remote control assembly 300 may include two processors. One processor (e.g., may include, but is not limited to, a CC2510 microcontroller / RF transceiver available from Chipcon AS (Oslo, Norway)) may be dedicated for wireless communication, for example, to communicate with the infusion pump assemblies 100, 100', 400, 500. A second processor included within the remote control assembly (which may include, but is not limited to, ARM920T and ARM922T manufactured by Holdings PLC (United Kingdom)) may be a command processor and may perform data processing tasks associated with steps for configuring the infusion pump assemblies 100, 100', 400, 500, for example.

[0546] Furthermore, as discussed above, one embodiment of the electric control assembly 816 may include three microprocessors. One processor (which may include, but is not limited to, a CC2510 microcontroller / RF transceiver available from Chipcon AS (Oslo, Norway), for example) may be dedicated to wireless communication, for example, to communicate with the remote control assembly 300. Two additional microprocessors (for example, the supervisor processor 1800 and the command processor 1802) may achieve the delivery of the injectable fluid (as discussed above). Examples of the supervisor processor 1800 and the command processor 1802 may include, but are not limited to, MSP430 microcontrollers available from Texas Instruments Inc. (Dallas, Texas).

[0547] The OS may be a non-preemptive scheduling system in that, regardless of priority, it executes until all tasks are completed before enabling the execution of the next task. Additionally, context switching may not occur. When a task completes execution, the highest priority task currently scheduled for execution may be executed. If no task is scheduled for execution, the OS may put the processor (for example, the supervisor processor 1800 and / or the command processor 1802) into a low-power sleep mode and may wake up when the next task is scheduled. The OS may be used only to manage the main loop code and may leave the interrupt-based functionality unaffected.

[0548] The OS may be written to utilize the C++ language. Inheritance as well as virtual functions may be important elements of a design that enable the easy creation, scheduling, and management of tasks.

[0549] At the root of the OS infrastructure, there may be the ability to track system time and control the ability to put the processor into a low-power mode (LPM, also known as the sleep mode). This functionality can be encapsulated by the SysClocks class, along with the control and configuration of all system clocks.

[0550] The SysClocks class may contain functionality to put the processor (e.g., the supervisor processor 1800 and / or the command processor 1802) into LPM to reduce energy consumption. While in LPM, the low-speed real-time clock may continue to run, while the high-speed system clock that executes the CPU core and most peripherals may be disabled.

[0551] Putting the processor into LPM can always be done by the provided SysClocks functionality. This functionality may contain all the necessary power-down and power-up sequences that provide consistency, whenever entering or exiting LPM. The return from LPM can be initiated by a low-speed clock-based interrupt.

[0552] The OS can track three aspects of time: seconds, milliseconds, and time of day. For seconds, SysClocks can count seconds starting from when the processor comes out of reset. The seconds counter may be based on the low-speed system clock and thus can increment whether the processor is in LPM or at full power. As a result, this is the boundary at which the processor resumes from sleep and executes previously scheduled tasks. If a task is scheduled to execute immediately after an interrupt service routine (ISR), the ISR may return the processor from LPM at the end so that the task can execute immediately. For milliseconds, in addition to counting seconds since power-on, SysClocks can count milliseconds while the processor is in full-power mode. Since the high-speed clock is stopped during LPM, the millisecond counter may not need to increment. Thus, the processor may not need to enter LPM whenever a task is scheduled to execute based on milliseconds. For time of day, the time can be represented within SysClocks as seconds since a specific point in time (e.g., seconds since January 1, 2004).

[0553] The SysClocks class can provide useful functionality that is used throughout the command and supervisor project codebase. Code delays may be necessary to allow hardware to settle or an action to complete. SysClocks can provide two forms of delay: delay based on seconds or delay based on milliseconds. When a delay is used, the processor may simply wait until the desired time has elapsed before continuing the current code path. During this time, only ISRs can execute. SysClocks can provide all the necessary functionality to set or retrieve the current time.

[0554] The term "task" may be associated with more complex scheduling systems and thus, within the OS, a task may be represented by, and may be called, Managed Functions. The ManagedFunc class may be an abstract base class that manages the desired functionality and provides all of the control elements and functionality necessary to schedule it.

[0555] The ManagedFunc base class may have five control elements, two of which are scheduling operation element functions and one of which is a pure virtual execution function that may contain the managed functionality. All of the ManagedFunc control elements may be hidden from derived classes and may only be set directly by the derived class during creation, thus simplifying usage and improving the safety of the injection pump assemblies 100, 100', 400, 500.

[0556] The function ID may be set at creation time and may never be changed. All function IDs may be defined within a single file and the base ManagedFunc constructor may enforce strongly that the same ID may not be used for more than one managed function. The ID may also define the priority of the function (relative to other functions) based on the assigned function ID, with higher priority functions having a lower assigned function ID. The highest priority task currently scheduled for execution may be executed before lower priority tasks.

[0557] All other control elements may be used to represent the current scheduled state of the function when it is to be executed and if the function is to be rescheduled at a previously set amount of time (at execution time). These control and state operations may be made possible only through well-known member functions (thus enforcing safety controls on all settings).

[0558] To control the scheduling of managed functions, setup start and setup repeat functions can be used. Each of these member functions can be a simple interface that enables the ability to configure or invalidate a repeating setup, as well as control whether a managed function is in an inactive state and is scheduled by seconds, milliseconds, or time.

[0559] Managed functions may be created by creating a derived class through inheritance and defining a pure virtual "execute" function that contains the code that needs to receive scheduling control. The ManagedFunc base class constructor may be based on a unique ID of the function, but can also be used to set default control values at startup.

[0560] For example, to create a function that runs 30 seconds after startup and then every 15 seconds thereafter, the desired code is placed in the virtual execute function, and the function ID, which is scheduled by the seconds state and has a start time of 30 seconds, and a repeat setting of 15 seconds are provided to the constructor.

[0561] The following is an example of exemplary code regarding the creation of a managed function. In this particular example, a "heartbeat" function is created that is scheduled to run for the first time 1 second after the startup of the infusion pump assemblies 100, 100’, 400, 500, and then every 10 seconds thereafter. #include “ManagedFunc.h” / / The SendGoodFunc is a “heartbeat” status message class SendGoodFunc : public ManagedFunc { public: / / Initialize the managed func to run 2 seconds after start up / / and repeat every second. SendGoodFunc(): ManagedFunc(IPC_SEND_GOOD, SCHEDULED_SEC, 1, true, 10) {}; ~SendGoodFunc() {}; protected: void execute(void); }; void SendGoodFunc::execute(void) { / / << code to send the heartbeat >> } SendGoodFunc g_sendGoodFunc; / / to manipulate the heartbeat timing simply call: / / g_sendGoodFunc.setFuncStart(…) or g_sendGoodFunc.setRepeat( … ) The actual execution of the managed function can be controlled and implemented by the SleepManager class. The SleepManager may contain the actual priority list of the managed functions. This priority list of functions may be automatically populated with data during the managed function creation process, ensuring that each function is properly created and has a unique ID.

[0562] The main role of the SleepManager class is to repeatedly call the "management" function from the main loop of the processor and / or from an endless while loop. At each call of management, SleepManager executes all functions that are scheduled to be executed until SleepManager has exhausted all scheduled functions, at which point SleepManager may put the processor into LPM. Once the processor resumes from LPM, the management function may be re-entered until the processor is ready to go into LPM again (this process may be repeated, for example, until stopped by the user or by the system).

[0563] If the processor must be kept in full power mode for an extended period (e.g., while analog / digital conversion is being sampled), SleepManager may provide functionality to disable going into LPM. While LPM is disabled, the management function may continue to search for scheduled tasks.

[0564] SleepManager may also provide an interface that manipulates scheduling and iterates the setup of any managed function through the use of unique IDs of the functions, which may enable any section of code to perform any necessary scheduling without direct access to or unnecessary knowledge of the desired ManagedFunc object.

[0565] The wireless circuits contained within each of the injection pump assemblies 100, 100', 400, 500, and the remote control assembly 300 may achieve wireless communication between the remote control assembly 300 and the injection pump assemblies 100, 100', 400, 500. A 2.4GHz wireless communication chip with an internal 8051 microcontroller (e.g., Texas Instruments CC2510 transceiver) may be used for the wireless communication.

[0566] The wireless link can maintain a balance among three objects: link availability, latency, and energy.

[0567] Regarding link availability, the remote control assembly 300 may provide primary means for controlling the infusion pump assemblies 100, 100', 400, 500, and can provide detailed feedback to the user via the graphical user interface (GUI) of the remote control assembly 300. Regarding latency, the communication system can be designed to provide low latency in delivering data from the remote control assembly 300 to the infusion pump assemblies 100, 100', 400, 500 (and vice versa). Regarding energy, both the remote control assembly 300 and the infusion pump assemblies 100, 100', 400, 500 can have a maximum energy consumption for wireless communication.

[0568] The wireless link can support half-duplex communication. The remote control assembly 300 can be the master of the wireless link that initiates all communications. The infusion pump assemblies 100, 100', 400, 500 may only respond to communications and never initiate communications. The use of such a wireless communication system can provide various benefits such as enhanced security, simplified design (e.g., for aircraft use), and coordinated control of the wireless link.

[0569] Referring also to FIG. 120A, an exemplary embodiment of one of the various software layers of the wireless communication system discussed above is shown.

[0570] The wireless processors included within remote control assembly 300 and infusion pump assemblies 100, 100', 400, 500 may transfer messaging packets between the SPI port and the 2.4 GHz wireless link (and vice versa). The wireless may always be an SPI slave. In infusion pump assemblies 100, 100', 400, 500, a wireless processor (PRP) 1818 (see FIGS. 115 - 116) may enable the use of two additional nodes on the upstream SPI port (i.e., command processor 1800 and supervisor processor 1802). In some embodiments, on remote control assembly 300, a wireless processor (CRP) may enable the use of two additional nodes on an SPI port that may be either upstream or downstream, for example, in some embodiments, the remote control processor (UI) and continuous glucose engine (CGE) described above.

[0571] A messaging system may enable the communication of messages between various nodes in a network. The UI processor of remote control assembly 300, and, for example, supervisor processor 1800, may use the messaging system to configure and initiate some of the mode switching on the two system wirelesses. It may also be used by the wireless to convey wireless and link state information to other nodes in the network.

[0572] If the wireless of remote control assembly 300 desires to collect channel statistics from infusion pump assemblies 100, 100', 400, 500, or update the master channel list of the wirelesses of infusion pump assemblies 100, 100', 400, 500, the wireless of remote control assembly 300 may use system messages. Synchronization to effectuate the new updated list may use an indicator with a heartbeat message to remove timing uncertainties.

[0573] The wireless communication system may be written in C++ to be compatible with messaging software. To handle each wireless node, a 4-byte wireless serial number may be used. A hash table may be used to provide a one-to-one translation between the device "readable" serial number sequence and the wireless serial number. The hash table may provide a more randomized 8-bit logical address so that pumps (e.g., infusion pump assemblies 100, 100', 400, 500) or controllers having similar readable serial numbers are likely to have unique logical addresses. The wireless serial numbers do not need to be unique between the pumps (e.g., infusion pump assemblies 100, 100', 400, 500) and the controller, depending on the unique role each has in the wireless protocol.

[0574] The wireless serial numbers of the remote control assembly 300 and the infusion pump assemblies 100, 100', 400, 500 may be included in all wireless packets except for RF pairing request messages that may contain only the wireless serial number of the remote control assembly 300, thus ensuring that it occurs only for the remote control assembly / infusion pump assembly it is paired with. The CC2510 may support a 1-byte logical node address, and it may be advantageous to use 1 byte of the wireless serial number as the logical node address to provide a level at which received packets are filtered.

[0575] To prevent noise interference on the substrate of the remote control assembly 300 by other systems on the substrate, the Quiet_Radio signal can be used by the UI processor of the remote control assembly 300. When Quiet_Radio is asserted, the wireless application of the remote control assembly 300 can send a message wirelessly to the wireless of the infusion pump assemblies 100, 100’, 400, 500 to assert the Radio Quiet mode for a predetermined period. The Quiet_Radio feature may not be required based on the noise interference level measured on the PC board of the remote control assembly 300. During this period, the wireless of the remote control assembly 300 can remain in sleep mode 2 for up to 100 ms. The wireless of the remote control assembly 300 can exit sleep mode 2 when the Quiet_Radio signal is de-asserted or when the maximum period has expired. The UI processor of the remote control assembly 300 can assert Quiet_Radio at least at one wireless communication interval before an event needs to be asserted. The wireless of the remote control assembly 300 can notify the wireless of the infusion pump assemblies 100, 100’, 400, 500 that communication is shut down during this sleep period. The periodic wireless link protocol can have status bits / bytes that accommodate the Quiet_Radio feature unless Quiet_Radio is required.

[0576] The wireless software can be integrated with the messaging system and the wireless bootloader on the same processor and can be verified using throughput tests. The wireless software can be integrated with the messaging system, the SPI driver using DMA, and the wireless bootloader all on the same processor (e.g., TI CC2510).

[0577] The wireless of the remote control assembly 300 can be configured to consume only 32 mAh in 3 days (assuming high heart rate mode communication for 100 minutes per day). The wireless of the infusion pump assemblies 100, 100', 400, 500 can be configured to consume only 25 mAh in 3 days (assuming high heart rate mode communication for 100 minutes per day).

[0578] The maximum time to reacquire communication can be ≤ 6.1 seconds, including the connection request mode and the acquisition mode. The wireless of the remote control assembly 300 can advantageously use the high heart rate mode or the low heart rate mode setting to save power and minimize the waiting time for the user. The difference between the infusion pump assemblies 100, 100', 400, 500 and the remote control assembly 300 in the acquisition mode may be that the infusion pump assemblies 100, 100', 400, 500 need to be in the acquisition mode at a frequency high enough to ensure that the communication can be restored within the maximum waiting time. However, the remote control assembly 300 may be in the low heart rate mode and vary the frequency of going into the acquisition mode with the infusion pump assemblies 100, 100', 400, 500 when the heart beat is lost. The wireless of the remote control assembly 300 may have knowledge of user GUI interactions, but it may not be necessary for the infusion pump assemblies 100, 100', 400, 500.

[0579] The wireless of the remote control assembly 300 can set the heartbeat periods for both wirelesses. The periods can be selectable to optimize power and link waiting time according to activities. The desired heartbeat period can be transmitted at each heartbeat from the wireless of the remote control assembly 300 to the wirelesses of the infusion pump assemblies 100, 100', 400, 500. This may not exclusively establish the heartbeat speeds of the infusion pump assemblies 100, 100', 400, 500 due to other conditions that determine which mode to enter. When in the high-speed heartbeat mode, the wireless of the remote control assembly 300 may set the heartbeat period to 20 ms if it is possible to transmit or receive data packets, and thus provide communication with less link waiting time when data is actively exchanged.

[0580] When in the high-speed heartbeat mode, the wireless of the remote control assembly 300 can set the heartbeat period to 60 ms after four heartbeats since the data packet was last exchanged in either direction on the wireless. By keeping the wireless heartbeat period short after a packet is transmitted or received, it is ensured that any data response packet can also be provided using less link waiting time. When in the low-speed heartbeat mode, the heartbeat speeds can be 2.00 seconds or 6.00 seconds respectively according to the online or offline state.

[0581] The infusion pump assemblies 100, 100', 400, 500 can use the heartbeat speeds set by the wireless of the remote control assembly 300. The wireless of the remote control assembly 300 can support the following mode requirements via a messaging system. · Pairing mode · Connection mode · Acquisition mode (including the wireless serial numbers of the desired paired infusion pump assemblies 100, 100', 400, 500) · Synchronization mode - high-speed heartbeat · Synchronization mode - low-speed heartbeat · RF off mode The wireless of the injection pump assemblies 100, 100', 400, 500 may support the following mode requirements via the messaging system. · Pairing mode · Acquisition mode · RF off mode The wireless may use system messages to obtain a local wireless serial number. On the remote control assembly 300, the wireless may obtain the serial number from the UI processor of the remote control assembly 300. The wireless may use system messages to store the pairing wireless serial number.

[0582] The wireless of the remote control assembly 300 and the injection pump assemblies 100, 100', 400, 500 may issue status messages to the UI processors of the remote control assembly 300 and the command processor 1802 using the messaging system whenever the following states change. · High-speed online: Connection successful · High-speed online: Change from acquisition mode to high-speed heartbeat mode · Low-speed online: Success of the change request from high-speed heartbeat to low-speed heartbeat · Offline: Automatic change to search synchronization mode due to lack of heartbeat exchange · High-speed online: Success of the change request from low-speed heartbeat to high-speed heartbeat · Offline: Bandwidth drops below 10% in synchronization mode · Online: Bandwidth increases by more than 10% in search synchronization mode · Offline: Success of the change request to RF off mode Wireless configuration messages may be used to configure the number of wireless retries. This message may be sent on the messaging system. The UI processor of the remote control assembly 300 sends this command to both the wireless of the remote control assembly 300 and the wireless of the injection pump assemblies 100, 100', 400, 500 to configure these wireless settings.

[0583] The wireless configuration message can have two parameters, namely, the number of RF retries (e.g., the value can range from 0 to 10), and the wireless offline parameter (e.g., the value can range from 1 to 100 as a percentage of the bandwidth).

[0584] The wireless applications on both the remote control assembly 300 and the injection pump assemblies 100, 100’, 400, 500 can have an API that enables the messaging system to configure the number of RF retries and the wireless offline parameter.

[0585] The following parameters may be recommended for the wireless hardware configuration. · Basic wireless specification · MSK · Wireless communication speed of 250 kbps or more · Up to 84 channels · Channel spacing of 1000 kHz · Filter bandwidth of 812 kHz · Without Manchester coding scheme · Data erasure · 4-byte preamble · 4-byte synchronization (phrase) · CRC added to the packet · LQI (Link Quality Indicator) added to the packet · Enabled automatic CRC filtering Forward error correction (FEC) may or may not be utilized. Forward error correction (FEC) can be used to increase the effective signal dynamic range by approximately 3 dB, but FEC requires a fixed packet size and doubles the number of wireless bits for the same fixed-size message.

[0586] Wireless can function within a distance of 1.83 meters under nominal operating conditions (except in pairing mode). It may be the goal for the wireless to function within a distance of 7.32 meters under nominal operating conditions. The transmission power level may be 0 dBm (except in pairing mode), and the transmission power level in pairing mode may be -22 dBm. Since the desired wireless node addresses of the injection pump assemblies 100, 100', 400, 500 may not be known to the remote control assembly 300 in pairing mode, both the injection pump assemblies 100, 100', 400, 500 and the remote control assembly 300 may use a lower transmission power to reduce the possibility of accidentally pairing with another injection pump assembly.

[0587] AES encryption may be used for all packets, but since the Texas Instruments CC2510 wireless transceiver includes this functionality, it may not be necessary. If AES encryption is used, a fixed key may be utilized to provide a quick way to enable encryption without passing a key. However, key exchange may be provided in future versions of the injection pump assemblies 100, 100', 400, 500. The fixed key may be contained in one separate header source without other variables other than the fixed key data, thus enabling easier management of read access to the file.

[0588] The wireless software may support the following eight modes. · Pairing mode · RF off mode · Connection mode · Acquisition mode · High-speed heartbeat mode · Low-speed heartbeat mode · Search synchronization mode · Synchronization acquisition mode These are depicted schematically in FIGS. 120B - 120C.

[0589] Pairing can be a process of exchanging wireless serial numbers between the remote control assembly 300 and the infusion pump assemblies 100, 100', 400, 500. The remote control assembly 300 can be "paired" with the infusion pump assemblies 100, 100', 400, 500 when the infusion pump assemblies 100, 100', 400, 500 know its serial number. The infusion pump assemblies 100, 100', 400, 500 can be "paired" with the remote control assembly 300 when the remote control assembly 300 knows its serial number.

[0590] The pairing mode (generally depicted schematically in FIG. 120D) may require that four messages be exchanged over the RF link. ·RF pairing request (sent from the remote control assembly 300 to any of the infusion pump assemblies 100, 100', 400, 500) ·RF pairing approval (from the infusion pump assemblies 100, 100', 400, 500 to the remote control assembly 300) ·RF pairing confirmation request (sent from the remote control assembly 300 to the infusion pump assemblies 100, 100', 400, 500) ·RF pairing confirmation approval (from the infusion pump assemblies 100, 100', 400, 500 to the remote control assembly 300) In addition, the remote control assembly 300 can abort the pairing process at any time via an RF pairing interruption message (sent from the remote control assembly 300 to the infusion pump assemblies 100, 100', 400, 500). The pairing mode may not support messaging system data transfer.

[0591] Upon receiving a pairing mode request message, the wireless of the infusion pump assemblies 100, 100', 400, 500 may enter the pairing mode. There are no disposable parts attached to the infusion pump assemblies 100, 100', 400, 500, and it may be the responsibility of the supervisor processor 1800 on the infusion pump assemblies 100, 100', 400, 500 to request that the wireless enter the pairing mode when the user presses the button on the infusion pump assemblies 100, 100', 400, 500 for 6 seconds. The wireless of the infusion pump assemblies 100, 100', 400, 500 may set an appropriate transmission power level for the pairing mode. The infusion pump assemblies 100, 100', 400, 500 may only be paired with one remote control assembly 300 at a time.

[0592] While in the pairing mode, upon receiving a first valid RF pairing request message, the wireless of the infusion pump assemblies 100, 100', 400, 500 may respond with an RF pairing approval message containing the wireless serial number of the infusion pump assemblies 100, 100', 400, 500, using the serial number of the remote control assembly 300 over the duration of the pairing mode.

[0593] The wireless of the infusion pump assemblies 100, 100', 400, 500 may automatically time out from the pairing mode 2.0 ± 0.2 seconds after if no RF pairing request is received. The wireless of the infusion pump assemblies 100, 100', 400, 500 may issue a pairing request received message after transmitting the RF pairing approval. This message to the supervisor processor enables feedback to the user during the pairing confirmation process. The wireless of the infusion pump assemblies 100, 100', 400, 500 may automatically time out from the pairing mode 1.0 ± 0.1 seconds after transmitting the RF pairing approval unless an RF pairing confirmation request is received. The wireless of the infusion pump assemblies 100, 100', 400, 500 may issue a stored message of the pairing wireless serial number if an RF pairing confirmation request message is received after receiving the RF pairing request message. This action may store the wireless serial number of the remote control assembly 300 in the non-volatile memory of the infusion pump assemblies 100, 100', 400, 500 and may overwrite the existing pairing data of the infusion pump assemblies 100, 100', 400, 500.

[0594] The wireless of the infusion pump assemblies 100, 100', 400, 500 may transmit an RF pairing confirmation approval and end the pairing mode after receiving approval from the stored message of the pairing wireless serial number. This may be a normal end of the pairing mode on the infusion pump assem...

Claims

【Claim 1】 An invention having support requirements and clarity requirements.

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