Method for estimating liquid delivery

Abstract

This invention relates to a system, method, and apparatus for liquid delivery using a syringe pump. [Solution] The plunger has a piston coupled to a shaft and is positioned inside the reservoir to slidably engage with the inner surface of the reservoir. The piston defines the liquid side and the non-liquid side of the reservoir, so that the movement of the plunger toward the liquid side of the reservoir discharges the liquid through the port. The pump also includes a reference volume assembly and / or a linear position sensor. The reference volume assembly includes a reference volume chamber coupled to the reservoir at the end opposite the reservoir to the port and acoustically communicating with the non-liquid side of the reservoir, a speaker positioned within the reference volume chamber, and a reference microphone positioned within the reference volume chamber. The reference volume assembly and / or the linear position sensor can be used to estimate the amount of liquid discharged from the reservoir.

Description

[Technical Field]

[0001] Cross-reference of related applications This application is a non-provisional application and is an international application filed under the Patent Cooperation Treaty, claiming the following priority rights and benefits. U.S. Provisional Patent Application No. 61 / 578,649, filed December 21, 2011, Title of Invention: "System, Method, and Apparatus for Infusing Fluid" (Agent Reference Number J02) U.S. Provisional Patent Application No. 61 / 578,658, filed December 21, 2011, Title of Invention: "System, Method, and Apparatus for Estimating Liquid Delivery" (Agent Reference Number J04) U.S. Provisional Patent Application No. 61 / 578,674, filed December 21, 2011, Title of Invention: "System, Method, and Apparatus for Dispensing Oral Medications" (Agent Reference Number J05) U.S. Provisional Patent Application No. 61 / 651,322, filed May 24, 2012, title of invention "System, Method, and Apparatus for Electronic Patient Care" (Agent Reference Number J46), and, U.S. Provisional Patent Application No. 61 / 679,117, filed 3 August 2012, title of the invention "System, Method, and Apparatus for Monitoring, Regulating, or Controlling Fluid Flow" (Agent Reference Number J30), each of which is incorporated herein by reference in whole. This application is also a continuation of the following application, and the priority and benefits thereof are claimed. U.S. Patent Application No. 13 / 333,574, filed December 21, 2011, title of invention "System, Method, and Apparatus for Electronic Patient Care," currently published U.S. Patent Application Publication No. US-2012-0185267-A1, published July 19, 2012 (Agent Reference Number l97), and, PCT application PCT / US11 / 66588, filed December 21, 2011, title of invention "System, Method, and Apparatus for Electronic Patient Care" (agent reference number l97WO), both of which are incorporated herein by reference in their entirety. This application may also relate to one or more of the following patent applications filed on the same day, all of which are incorporated herein by reference in their entirety. Non-provisional application for "System, Method, and Apparatus for Clamping" (Agent reference number J47) Non-provisional application for "System, Method, and Apparatus for Dispensing Oral Medications" (Agent reference number J74), Non-provisional application for "System, Method, and Apparatus for Estimating Liquid Delivery" (Agent reference number J75) Non-provisional application for "System, Method, and Apparatus for Infusing Fluid" (Agent reference number J76), PCT application for "System, Method, and Apparatus for Infusing Fluid" (Agent reference number J76WO), Non-provisional application for "System, Method, and Apparatus for Electronic Patient Care" (Agent reference number J77), Non-provisional application for "System, Method, and Apparatus for Electronic Patient Care" (Agent reference number J78), Non-provisional application for "System, Method, and Apparatus for Monitoring, Regulating, or Controlling Fluid Flow" (Agent reference number J79), PCT application for "System, Method, and Apparatus for Monitoring, Regulating, or Controlling Fluid Flow" (Agent reference number J79WO), A non-provisional application (agent reference number J81) for "System, Method, and Apparatus for Estimating Liquid Delivery," and, Non-provisional application for "System, Method, and Apparatus for Electronic Patient Care" (Agent reference number J85). background Related fields

[0002] This disclosure relates to pumps. More specifically, this disclosure relates to systems, methods, and apparatus for liquid delivery using syringe pumps. Description of related technologies

[0003] Syringe pumps are used in a variety of medical applications, such as intravenous delivery of liquid medications, for example, for patients in intensive care units (ICUs) for extended periods. Syringe pumps can be designed to accommodate needles, tubes, or other accessories. Generally, a syringe pump includes a plunger attached to a shaft that pushes liquid from a reservoir. The reservoir may be a tubular structure with a port at one end, and the plunger can push (i.e., discharge) liquid from the syringe pump. The syringe pump can be coupled to an actuator, which mechanically drives the plunger to control the delivery of liquid to the patient.

[0004] Syringe pumps can also be used to deliver a variety of drugs, including analgesics, antiemetics, or other fluids. Drugs can be administered very rapidly (e.g., in large, instantaneous doses) or over extended periods via intravenous lines. Syringe pumps can also be used in non-medical applications, such as in small reactors, testing, and / or chemical processing applications. [Overview of the Initiative]

[0005] In one embodiment of this disclosure, the pump includes a reservoir, a port, a plunger, and a reference volume assembly. The reservoir is configured to deliver liquid. The port is coupled to the reservoir and configured to discharge liquid. The plunger includes a piston coupled to a shaft. The piston is located within the reservoir and slides with the inner surface of the reservoir. The movement of the plunger toward the liquid side of the reservoir discharges liquid through the port, by the piston defining the liquid side and the non-liquid side of the reservoir. The reference volume assembly is coupled to the reservoir at the end opposite the port. The reference volume assembly includes a reference volume chamber, a speaker, and a reference microphone. The reference volume chamber is in acoustic communication with the non-liquid side of the reservoir. The speaker and the reference microphone are located within the reference volume chamber. A variable volume microphone may be located within the reservoir to detect sound waves within the reservoir and / or located in the reference volume assembly to detect sound waves within the reservoir.

[0006] In other aspects of this disclosure, the system may include a pump (as described above), an actuator, a linear position sensor, and a processor. The actuator is coupled to the shaft of the pump to start the pump, and the linear position sensor is coupled to the shaft to detect the position of the shaft. The processor is coupled to the actuator and the linear position sensor to estimate the amount of liquid discharged as a function of the position of the shaft.

[0007] In other embodiments, the system may include a pump (as described above), a variable volume microphone, and a processor. The variable volume microphone detects sound waves within the non-liquid side of the reservoir. The processor is coupled in conjunction with a speaker and a reference and variable volume microphone to generate a number of acoustic frequencies and to instruct them to estimate the amount of liquid discharged as a function of acoustic feedback from the variable volume and reference microphones.

[0008] In yet another aspect of this disclosure, the pump includes a reservoir, a port, a plunger, a further reservoir, a further port, a further plunger, and a reference volume assembly. The reservoir is configured to deliver liquid. A port is connected to the reservoir and configured to discharge liquid. The plunger includes a piston connected to a shaft. The piston is located inside the reservoir and slides against the inner surface of the reservoir. The piston defines the liquid side and the non-liquid side of the reservoir, so that the movement of the plunger toward the liquid side of the reservoir discharges liquid through the port.

[0009] Further storage units are configured to deliver additional liquid. Further ports are connected to further storage units and configured to discharge additional liquid. The further plunger includes a further piston coupled to a further shaft. The further piston is positioned within the further reservoir and slides against the inner surface of the further reservoir. The further piston defines the liquid side and the non-liquid side of the further reservoir, so that the movement of the plunger toward the liquid side of the further reservoir discharges the liquid through the further port.

[0010] The reference volume assembly is coupled to a reservoir at the opposite end of the reservoir with respect to a port, and the reference volume assembly is further coupled to a further reservoir at the opposite end of the further reservoir with respect to a further port. The reference volume assembly includes a reference volume chamber, a speaker, and a reference microphone. The reference volume chamber is acoustically in communication with the non-liquid side of the reservoir, and the reference volume chamber is acoustically in communication with the non-liquid side of the further reservoir. The speaker and the reference microphone are located within the reference volume chamber. Selectively, one or more of the first and second reservoirs can be attached to the reference volume assembly.

[0011] In other embodiments of this disclosure, the pump includes a manifold. The manifold includes first and second connector ports, a discharge port, and a fluid path. The first connector port is coupled to a port, and the second connector port is coupled to a further port. The fluid path fluidly connects the first and second connector ports together to the discharge port. The manifold is selectively mountable to the first and second connector ports.

[0012] In other embodiments of this disclosure, the pump includes a variable volume microphone located in a reservoir or on a reference volume assembly and configured to detect sound waves in the reservoir. The pump may also include a further variable volume microphone located in a further reservoir on the reference volume assembly and configured to detect sound waves in the further reservoir.

[0013] In other embodiments of this disclosure, a system for estimating liquid delivery includes the pump, variable volume microphone, and processor described above. The variable volume microphone detects sound waves within the non-liquid side of the reservoir. The processor is coupled in conjunction with a speaker and the reference and variable volume microphones. The processor is configured to instruct the speaker to generate a plurality of acoustic frequencies to estimate the amount of liquid discharged as a function of acoustic feedback from the variable volume and reference microphones.

[0014] In yet another embodiment of this disclosure, the pump includes an acoustic housing, a reservoir, a port, a plunger, and a reference volume assembly. The reservoir is configured to deliver liquid and is located within the acoustic housing. The port is coupled to the reservoir and is configured to discharge liquid. The plunger has a piston coupled to a shaft. The plunger is located within the acoustic housing, and the piston is located within the reservoir so as to slide and engage with the inner surface of the reservoir. The piston defines the liquid side and the non-liquid side of the reservoir, so that the movement of the plunger toward the liquid side of the reservoir discharges liquid through the port. The reference volume assembly is coupled to the acoustic housing through the acoustic port. The reference volume assembly includes a reference volume chamber, a speaker, and a reference microphone. The reference volume chamber is acoustically in communication with the acoustic housing through the acoustic port. The speaker is located within a reference volume chamber, and the reference microphone is also located within a reference volume chamber. The pump may also include an actuator coupled to a shaft to drive a plunger, which may be located within an acoustic housing.

[0015] The pump may also include a further reservoir, a further port, and a further plunger. The further reservoir is configured to deliver further liquid and is located within an acoustic housing. The further port is coupled to the further reservoir and is configured to discharge further liquid. The further plunger has a further piston coupled to a further shaft. The further plunger is located within an acoustic housing, and the further piston is located within the further reservoir so as to slide and engage with the inner surface of the further reservoir. The further piston defines the liquid side and the non-liquid side of the further reservoir, so that the movement of the further plunger toward the liquid side of the further reservoir discharges liquid through the further port.

[0016] The pump may include a manifold. The manifold includes first and second connector ports, a discharge port, and a liquid path. The first connector port is coupled to a port, and the second connector port is coupled to a further port. The liquid path fluidly connects the first and second connector ports together to the discharge port. The manifold is selectively attachable to the first and second connector ports.

[0017] In still further aspects of the present disclosure, a system for estimating liquid delivery includes a pump (such as those described above), an actuator, a linear position sensor, and a processor. The actuator is coupled to a shaft. The linear position sensor is coupled to the shaft and configured to detect the position of the shaft. The processor is communicatively coupled to the actuator and the linear position sensor and estimates the amount of liquid discharged as a function of the position of the shaft (such as that determined by the linear position sensor).

[0018] In a further aspect of the present disclosure, a system for estimating liquid delivery as described above includes a pump (such as those described above), a variable volume microphone, and a processor. The variable volume microphone senses sound waves within the non-liquid side of a reservoir. The processor is communicatively coupled to a speaker and the reference and variable volume microphones. The processor is configured to command the speaker to generate a plurality of acoustic frequencies and estimate the amount of liquid discharged as a function of the acoustic feedback from the variable volume and reference microphones.

[0019] In still other aspects of the present disclosure, the pump includes an acoustic housing, a further acoustic housing, a reservoir, a port, a plunger, a further reservoir, a further port, a further plunger, and a reference volume assembly. The reservoir is configured to deliver liquid and is disposed within the acoustic housing. The port is coupled to the reservoir and is configured to discharge liquid. The plunger has a piston coupled to a shaft. The plunger is disposed within the acoustic housing. The piston is disposed within the reservoir and slidably engages the inner surface of the reservoir, and the piston defines the liquid side and the non-liquid side of the reservoir such that movement of the plunger toward the liquid side of the reservoir discharges liquid through the port. The further reservoir is configured to deliver further liquid. The further reservoir is disposed within the further acoustic housing. The further port is coupled to the further reservoir and is configured to discharge further liquid. The further plunger has a further piston coupled to a further shaft. The further plunger is disposed within the further acoustic housing. The further piston is disposed within the further reservoir and slidably engages the inner surface of the further reservoir. The further piston defines the liquid side and the non-liquid side of the further reservoir such that movement of the plunger toward the liquid side of the further reservoir discharges liquid through the further port.

[0020] The reference volume assembly is coupled to the acoustic housing through an acoustic port and to the further acoustic housing through a further acoustic port. The reference volume assembly includes a reference volume chamber, a speaker, and a reference microphone. The reference volume chamber is acoustically communicable with the acoustic housing through the acoustic port. The reference volume chamber is acoustically communicable with the further acoustic housing through the further acoustic port. The speaker is disposed within the reference volume chamber. The reference microphone is disposed within the reference volume chamber.

[0021] The pump may also include an actuator coupled to a shaft to actuate a plunger. The actuator may be located within an acoustic housing. The pump may also include further actuators coupled to further shafts to actuate further plungers.

[0022] The pump may also include a manifold. The manifold includes first and second connector ports, a discharge port, and a fluid path. The first connector port is coupled to a port, and the second connector port is coupled to a further port. The fluid path fluidly connects the first and second connector ports together to the discharge port. The manifold can be selectively attached to the first and second connector ports.

[0023] In further embodiments of this disclosure, a system for estimating liquid delivery includes a pump (as described above), an actuator, a linear position sensor, and a processor. The actuator is coupled to a shaft. The linear position sensor is coupled to the shaft and configured to detect the position of the shaft. The processor is coupled in conjunction with the actuator and the linear position sensor and configured to estimate the amount of liquid discharged as a function of the position of the shaft.

[0024] In yet another embodiment, the system for estimating liquid delivery includes a pump (as described above), a variable volume microphone, and a processor. The variable volume microphone detects sound waves within the non-liquid side of the reservoir. The processor is coupled in conjunction with a speaker and a reference and variable volume microphone. The processor is configured to instruct the speaker to generate a plurality of acoustic frequencies and estimate the amount of liquid discharged as a function of acoustic feedback from the variable volume and reference microphone.

[0025] In further embodiments of this disclosure, the pump includes a reservoir, a port, a plunger, and a linear position sensor. The reservoir is configured to deliver liquid. The port is coupled to the reservoir and configured to discharge liquid. The plunger has a piston coupled to a shaft. The piston is positioned within the reservoir so as to slide and engage with the inner surface of the reservoir. The piston defines the liquid side and the non-liquid side of the reservoir, so that the movement of the plunger toward the liquid side of the reservoir discharges the liquid through the port. A linear position sensor is configured to detect the position of the shaft.

[0026] The pump may also include a housing, with the reservoir and plunger located within the housing. The pump may also include an actuator coupled to a shaft to actuate the plunger, which is located within the housing. A linear position sensor may also be located within the housing.

[0027] The pump may further include a further reservoir, a further port, a further plunger, and a further linear position sensor. The further reservoir is configured to deliver further liquid. The further port is coupled to the further reservoir and configured to discharge further liquid. The further plunger has a further piston coupled to a further shaft. The further piston is positioned within the further reservoir so as to slide and engage with the inner surface of the further reservoir. The further piston defines the liquid side and the non-liquid side of the further reservoir, so that the movement of the further plunger toward the liquid side of the further reservoir discharges liquid through the further port. The further linear position sensor is configured to detect the position of the further shaft.

[0028] The pump may also include a manifold. The manifold includes first and second connector ports, a discharge port, and a fluid path. The first connector port is coupled to a port, and the second connector port is coupled to a further port. The fluid path fluidly connects the first and second connector ports together to the discharge port. The manifold can be selectively attached to the first and second connector ports.

[0029] The pump may also include a housing, in which a reservoir and further reservoirs are arranged within the housing, and a plunger and further plungers are also arranged within the housing.

[0030] The pump may also include an actuator coupled to a shaft to actuate a plunger, and further actuators may be connected to further shafts to actuate further plungers. The actuators and further actuators may be arranged within a housing. Linear position sensors and / or further linear position sensors may be capacitive sensors coupled to a shaft or linear optical position sensor. The linear position sensors and / or further linear position sensors may be arranged within a housing.

[0031] In some embodiments of this disclosure, the linear position sensor includes an optical target and an optical ranging assembly. The optical target is coupled to a shaft. The optical ranging assembly is configured to estimate the linear position of the shaft by determining the range of the optical target.

[0032] The optical target may be a reflective target, and the optical ranging assembly may include an illuminator configured to illuminate the reflective target, thereby determining the linear position of the shaft from the reflection of the illumination of the reflective target.

[0033] The optical target may be a light source, and the optical ranging assembly may be configured to determine the linear position of the shaft from the measured intensity of the light source measured by the optical ranging assembly.

[0034] In other embodiments of this disclosure, a system for estimating liquid delivery includes a pump, an actuator, and a processor. The actuator is coupled to a shaft, and the processor is coupled in conjunction with the actuator and a linear position sensor to estimate the amount of liquid discharged as a function of the position of the shaft.

[0035] In yet another embodiment of this disclosure, one or more pumps described herein may include one or more optional features as follows: One or more pistons of the pumps described herein may include seals arranged around the periphery of the piston. The reservoir may be cylindrical in shape, thereby defining a circular cross-section, and the piston may engage with the inner surface of the reservoir along the circular cross-section. The reservoir may be rectangular in shape, thereby defining a rectangular cross-section, and the piston may engage with the inner surface of the reservoir along the rectangular cross-section.

[0036] The pump may include a discharge port that is in fluid communication with the non-liquid side of the storage container. This discharge port may be further configured to acoustically seal the non-liquid side of the storage container from the outside.

[0037] The pump described herein may include a one-way valve that is in fluid communication with the non-liquid side of the reservoir. This one-way valve may be configured to allow gas to be introduced from outside the storage container into the non-liquid side of the storage container.

[0038] One or more pumps described herein may include a plunger which is movable between a fully discharged position and a fully loaded position, and when the plunger is located anywhere between the fully discharged position and the fully loaded position, the reference volume chamber is in fluid communication with the non-liquid side of the reservoir.

[0039] The pumps described herein may further include a reference volume chamber, which includes piping configured to house a shaft. The shaft may be slidably engaged with the piping. The piping may further include a seal, which houses the shaft and is configured to acoustically seal the non-liquid side of the reservoir as the shaft engages with the piping. The reference volume assembly may further include an acoustic port that acoustically communicates with the reference volume chamber and the non-liquid side of the reservoir.

[0040] The pumps described herein may include a variable volume microphone. The non-liquid side of the reservoir may be configured to accommodate the variable volume microphone for mounting on the inner surface of the reservoir. The variable volume microphone is configured to detect sound waves within the non-liquid side of the reservoir. Additionally or alternatively, a variable volume microphone may be mounted on the reference volume assembly to detect sound waves within the non-liquid side of the storage container.

[0041] The actuators described herein may be linear actuators, screw-type linear actuators, linear track actuators, linear servo motors, linear stepper motors, linear motors, or other actuators.

[0042] In further embodiments of the present disclosure, for example, a method for estimating the delivery of liquid includes one or more actions: (1) positioning the plunger of a pump to a first position; (2) generating sound waves; (3) applying the sound waves to a reference chamber; (4) transmitting the sound waves to the non-liquid side of a reservoir of the pump; (5) detecting the sound waves in the reference chamber; (6) detecting the sound waves on the non-liquid side of the reservoir of the pump; (7) comparing the sound waves detected in the reference chamber with the sound waves detected on the non-liquid side of the reservoir to determine a first volume of liquid in the liquid side of the reservoir; (8) acting the plunger of the pump to a second position; (9) comparing the sound waves detected in the reference chamber with the sound waves detected on the non-liquid side of the reservoir to determine a second volume of liquid in the liquid side of the reservoir; and / or (10) comparing the first volume with the second volume to determine the amount of liquid discharged.

[0043] In yet another aspect of this disclosure, a system for preparing a syringe pump includes a monitoring client, a pharmacy computer, a dispensing robot, a syringe pump, and a data download device. The syringe pump may be any of those disclosed above or herein. The monitoring client is configured to communicate prescription orders via a user interface. The pharmacy computer communicates operationally with the monitoring client to receive prescription orders. The dispensing robot is configured to dispense the prescription into at least one liquid corresponding to the prescription order. The syringe pump is configured to receive at least one liquid corresponding to the prescription order. The data download device is configured to download the prescription order into the memory of the tablet dispenser. The syringe pump includes a reference volume attached thereto. The dispensing robot may fill the syringe pump with at least one liquid. The dispensing robot may communicate operationally with the data download device. The dispensing robot may instruct the data download device to download the prescription order into the memory of the tablet dispenser. The data download device may receive prescription orders from the dispensing robot and / or pharmacy computer. [Brief explanation of the drawing]

[0044] These and other embodiments will become more apparent from the following detailed description of various embodiments of the present disclosure with reference to the drawings.

[0045] [Figure 1] Figure 1 illustrates an electronic patient nursing system having a syringe pump according to an embodiment of the present disclosure.

[0046] [Figure 2] Figure 2 is a block diagram of a system for controlling a syringe pump according to an embodiment of the present disclosure.

[0047] [Figure 3] Figure 3 illustrates a syringe pump having a reference volume assembly coupled to the reservoir of the syringe pump for acoustically estimating the amount of liquid discharged by the syringe pump according to an embodiment of the present disclosure.

[0048] [Figure 4] Figure 4 illustrates a syringe pump having two reservoirs and a reference volume assembly coupled to these reservoirs, for acoustically estimating the amount of liquid discharged by the syringe pump, according to an embodiment of the present disclosure.

[0049] [Figure 5] Figure 5 illustrates a syringe pump having two reservoirs arranged within an acoustic housing and a reference volume assembly coupled to the acoustic housing, which acoustically estimates the amount of liquid discharged by the syringe pump.

[0050] [Figure 6] Figure 6 illustrates a syringe pump that acoustically estimates the amount of liquid discharged by the syringe pump, having two reservoirs, each located within its own acoustic housing, and a reference volume assembly coupled to the acoustic housing, according to an embodiment of the present disclosure.

[0051] [Figure 7] Figure 7 illustrates a syringe pump according to an embodiment of the present disclosure, which has two storage containers and two volume sensors, each coupled to a plunger in the respective storage container, and estimates the amount of liquid discharged by the syringe pump.

[0052] [Figure 8] Figure 8 illustrates a syringe pump according to an embodiment of the present disclosure, which has two reservoirs and two reflective targets, each coupled to a plunger in the respective reservoir, and uses an optical ranging assembly to estimate the amount of liquid discharged by the syringe pump.

[0053] [Figure 9] Figure 9 illustrates a syringe pump according to an embodiment of the present disclosure, which has two reservoirs and two light sources, each coupled to a plunger in the respective reservoir, and estimates the amount of liquid discharged by the syringe pump using an optical ranging assembly.

[0054] [Figure 10] Figure 10 illustrates a syringe pump according to an embodiment of the present disclosure, which has two storage containers and two linear optical position sensors, each coupled to a plunger in the respective storage container, and estimates the amount of liquid discharged by the syringe pump.

[0055] [Figure 11] Figure 11 shows a flowchart illustrating a method for estimating liquid delivery according to an embodiment of the present disclosure. [Figure 12] Figure 12 shows a flowchart illustrating a method for estimating liquid delivery according to an embodiment of the present disclosure. [Modes for carrying out the invention]

[0056] Figure 1 shows an exemplary configuration of an electronic patient care system 1 according to an embodiment of the present disclosure. The system 1 includes a monitoring client 2, which is linked to a number of patient care devices via docks 3 and 11, and includes an infusion pump 4 connected to a small bag of liquid 5 for delivery from there, an infusion pump 6 connected to a large bag of liquid 7 for delivery from there, a drip detection device 8 connected to a tubing system from the small bag 5, and a microinfusion pump 9. The system 1 also includes a syringe pump 10 wirelessly connected to the monitoring client 2. In one embodiment, the monitoring client 2 may communicate with these patient care devices in a wired manner, as shown in Figure 1, for the infusion pumps 4 and 6 and the microinfusion pump 9 (via docks 3 and 11). In addition to or instead of this, the monitoring client 2 may communicate with the patient care devices wirelessly, as suggested by the absence of a wired connection between the syringe pump 10 and the monitoring client 2.

[0057] In one embodiment, a wired connection between the monitoring client 2 and the patient care device provides an opportunity to supply power from the monitoring client 2 to the patient care device. In this exemplary embodiment, the monitoring client 2 may include electronic circuitry, which is necessary to convert a voltage from either a battery attached to the monitoring client 2 or an alternating current ("AC") line voltage supplied to the monitoring client 2 from an outlet in the patient room (not shown) to power the patient care device. In addition to or instead of this, the dock 3 supplies power to the infusion pumps 4 and 6, and to the microinfusion pump 9, for example, from a signal generated from the AC line voltage.

[0058] In one embodiment, the monitoring client 2 is capable of receiving information about each patient care device, which is linked either directly from the device itself or via a docking station, such as a dock 3 to which the patient care devices can be attached. The dock 3 may be configured to accommodate one or more patient care devices via standardized connection mounts, or in some cases, via connection mounts that are individually distinguished for specific devices. For example, infusion pumps 4 and 6 may be attached to the dock 3 via similar connection mounts, while the microinfusion pump 9 may be attached to the dock 3 via a connection mount configured for specific dimensions of the housing of the microinfusion pump 9, for example.

[0059] Dock 3 may be configured to electronically recognize specific patient nursing devices attached to the docking station and to transmit this recognition information to the monitoring client 2 either wirelessly or via a wired connection. In addition to or instead of this, wireless patient nursing devices may transmit recognition information wirelessly to the monitoring client 2, for example, during a discovery protocol. Furthermore, specific patient nursing devices may be pre-programmed with treatment information (e.g., patient treatment parameters such as the infusion rate for a predetermined infusion fluid) transmitted to the monitoring client 2. For example, syringe pump 10 may include recognition information and treatment information such as what drugs have been prescribed to the patient, what fluids are in the syringe pump 10's reservoir, how much fluid is prescribed to be delivered to the patient and for how long, and who the authorized caregiver is. In some embodiments of this disclosure, the monitoring client 2 communicates with the EMR record to verify that the pre-programmed treatment information is safe for the identified patient and / or that the pre-programmed treatment information is consistent with the prescribed treatments stored in the EMR record.

[0060] In one embodiment, the drip detection device 8 may communicate with the monitoring client 2 wirelessly or via a wired connection. If an abnormal liquid flow condition is detected (for example, due to an obstruction in the tubing to the patient), a signal may be sent to the monitoring client 2, which may (1) display the liquid flow rate from the liquid container 5 locally on the monitoring client 2 in the user interface, or more remotely on the user interface of the nurse's station or a portable communication device, (2) activate an audible or visual alarm, or (4) cause the monitoring client 2 to change the infusion rate of the pump 4 connected to the bag 5, either by terminating the infusion or changing the pumping rate. The abnormal liquid flow condition may cause the infusion pump 4 or the drip detection device 8 to produce an audible alarm (and / or vibration alarm), or cause the infusion pump 4 to change or stop pumping, for example, when the abnormal liquid flow condition exceeds a predetermined range of operation.

[0061] Alarms may occur simultaneously on several devices or in accordance with a predetermined schedule. For example, when an obstruction occurs in a line connected to the injection pump 4, (1) the drip detection device 8 will sound an alarm using its built-in speaker and vibration motor, (2) then the injection pump 4 will sound an alarm using its built-in speaker and vibration motor, (3) then the monitoring client 2 will sound an alarm using its built-in speaker and vibration motor, and (5) finally, the remote communication device (e.g., smartphone, BlackBerry, Android phone, iPhone®, etc.) will sound an alarm using its built-in speaker and vibration motor. In one embodiment, the syringe pump 10 may be detected by the drip detection device 8 to detect an abnormal liquid flow condition as described above.

[0062] In one embodiment, the syringe pump 10 may be programmable to continue operation when a predetermined pumping speed is lost due to a failure in the monitoring client 2 or the syringe pump 10 itself in the communication channel between the monitoring client 2 and the pumping pump 10, either due to a failure in the monitoring client 2 or in the syringe pump 10 itself. In one embodiment, this independent function selection is enabled when the injected pharmaceutical is not predetermined to be held or supported in the event of a failure in another part of the system. In one embodiment, the syringe pump 10 may also be programmed to operate independently in fail-safe mode and configured to receive information directly from the drip detection device 8 rather than through the monitoring client 2 (for example, in an embodiment where the drip detection device 8 is used in conjunction with the syringe pump 10), and according to this selection, the syringe pump 10 may be programmed to stop injection if the drip detection device 8 detects an abnormal flow condition (e.g., a free flow condition or bubbles present in the injection line). In some embodiments, one or more pumps 4, 6, and 10 may have built-in liquid flow meters and / or may operate independently as standalone devices. In addition to or instead of this, the built-in liquid flow meter of syringe pump 10 may be measured independently by the flow meter of drip detection device 8 by the monitoring client 2 in embodiments in which devices 8 and 10 are used together.

[0063] The monitoring client 2 may also remotely transmit prescriptions to the pharmacy. The prescription may be for injecting fluid using the syringe pump 10. The pharmacy may include one or more computers connected to a network, such as the Internet, which receive the prescription and place it in a queue on one or more computers. The pharmacy prepares the medicine using the prescription (e.g., using an automated dispensing device connected to one or more computers, or manually by a pharmacist who can see the queue on one or more computers), pre-fills the fluid reservoir or cartridge of the syringe pump 10, and / or programs the syringe pump 10 according to the prescription at the pharmacy (e.g., the treatment is programmed into the syringe pump 10). The reservoir or cartridge may be automatically filled by the automated dispensing device, and / or the syringe pump 10 may be automatically programmed by the automated dispensing device. The automated dispensing device may generate barcodes, RFID tags, and / or data. The information in the barcodes, RFID tags, and / or data may include treatment, prescriptions, and / or patient information. The automated dispensing device may have a barcode attached to the syringe pump 10, or to the storage container, cartridge, or disposable part of the syringe pump 10, and / or program an RFID tag or memory within the syringe pump 10, or the storage container, cartridge, or disposable part of the syringe pump 10 with information or data. This data or information may be transmitted to a database, which is associated with prescriptions made by the syringe pump 10 or the storage container, cartridge, or disposable part of the syringe pump 10 using, for example, a barcode, RFID tag, serial number in memory, or other identification information.

[0064] The syringe pump 10 may have a scanner, for example, an RFID questioner that queries the reservoir, disposable part, or cartridge of the infusion pump 10, to determine whether the correct fluid is in the fluid reservoir, or whether it is the correct fluid reservoir disposable part or cartridge, whether the procedure programmed into the syringe pump 10 corresponds to the fluid in the fluid reservoir disposable part or cartridge, and / or whether the syringe pump 10 and the reservoir disposable part or cartridge of the syringe pump 10 are appropriate for a particular patient (determined, for example, from the patient's barcode, RFID, or identification of another patient). For example, the serial number of the disposable reservoir portion scanned by the syringe pump 10 is compared with the serial number in the electronic medical record to determine whether it correctly matches the patient's serial number in the electronic medical record. The syringe pump 10 also scans the patient's RFID tag or barcode to obtain the patient's serial number, which is also compared with the serial number in the electronic medical record (for example, the serial number of the disposable reservoir portion or cartridge of the syringe pump 10, or the serial number stored in the memory of the syringe pump 10, must correspond to the patient's serial number scanned in the electronic medical record). In certain embodiments, if the serial numbers do not match, the syringe pump 10 may issue an error or alarm. In addition to or instead of this, the monitoring client 6 may scan the fluid reservoir, disposable part, cartridge, or syringe pump 10 and determine that the correct fluid is in the fluid reservoir, that it is the appropriate fluid reservoir, that the action programmed to the syringe pump 10 corresponds to the fluid in the fluid reservoir or cartridge, and / or that the fluid reservoir and syringe pump 10 are appropriate for a particular patient (for example, as determined from the patient's barcode, RFID, or identification of another patient). In addition to or instead of this, the monitoring client 6 or syringe pump 10 may query the electronic medical record database and / or pharmacy to verify or download a prescription, for example using the serial number on the syringe pump 10, or on the reservoir, cartridge, or disposable part of the syringe pump 10.

[0065] The liquid being delivered to the patient may be monitored by monitoring client 2 to determine whether all delivered drugs are safe for the patient. For example, monitoring client 2 may record the drugs delivered from syringe pump 10 so that the syringe pump 10 communicates this to monitoring client 2, and monitoring client 2 may also record drugs delivered by infusion pumps 4 and 6 and / or microinfusion pump 9. Monitoring client 1 may also make determinations from the recorded data to determine whether the total amount and form of delivered drugs are safe. For example, monitoring client 2 may determine whether IV bag 5 is contraindicated to the drugs in syringe pump 10. In addition or alternatively, in some embodiments, monitoring client 2 may monitor the delivery of the liquid in IV bag 8 and one or more rapid intravenous infusions delivered by syringe pump 10 to determine whether the total dose exceeds a predetermined threshold, for example, whether the drugs in IV bag 5 and syringe pump 10 are of the same form or type, and monitoring client 2 may determine whether the drugs are safe when delivered to the patient and combined. The syringe pump 10 may communicate with the infusion pumps 4 and 6 and / or the microinfusion pump 9 and make similar determinations. In this exemplary embodiment, the syringe pump 10 may communicate with the device directly (via wireless or wired communication) or through the monitoring client 2 (via wireless or wired communication). In some embodiments of the present disclosure, one or more communication modules (e.g., each capable of communicating by one or more protocols) may be connected to and / or together with the syringe pump 10 to enable the syringe pump 10 to communicate via the communication modules.

[0066] The syringe pump 10 includes a touchscreen interface 11 (which may be removable), a start button 12, and a stop button 13. The user interface 11 can be used to program a treatment, such as flow rate, rapid intravenous injection volume, or other treatment parameters. After the treatment is programmed into the syringe pump 10, the syringe pump 10 may query a database (e.g., an electronic medical record ("EMR"), a drug error reduction system ("DERS"), or other database) to determine whether the treatment is safe for a particular patient or for any patient. For example, the syringe pump 10 may query the EMR database (e.g., via a wireless link, wired link, WiFi, a cellular network, or other communication technology) to determine whether the treatment from the syringe pump 10 is safe based on patient information stored in the EMR record (e.g., age, weight, allergies, health condition, etc.). In addition to or instead of this, the syringe pump 10 may query the DERS database (e.g., via a wireless link, wired link, WiFi, a cellular network, or other communication technology) to determine whether the treatment from the syringe pump 10 is safe based on predetermined safety criteria in the DERS record.

[0067] In one embodiment, if the treatment is determined to be safe, the prompt may request user confirmation of the treatment. After user confirmation, the user (e.g., caregiver, nurse, or other authorized person) will press the start button 12. In one embodiment, the stop button 13 can be pressed at any time to stop the treatment.

[0068] In one embodiment, if the EMR and / or DERS determine that the treatment exceeds a first set of criteria, the treatment may continue if the user confirms the treatment (e.g., by further warnings, a user passcode, and / or further authentication or authorization, etc.). In this embodiment, if the EMR and / or DERS determine that the treatment exceeds a second set of criteria, for example, that the treatment is unsafe for any patient under certain circumstances, the EMR or DERS may prevent the treatment from being delivered.

[0069] Figure 2 is a block diagram of a system 14 for controlling a syringe pump according to an embodiment of the present disclosure. The system 14 in Figure 2 can be used to control the syringe pump 10 in Figure 1, or the syringe pump in Figure 3-10, as described later.

[0070] System 14 includes one or more sensors 15, a control system 16, a drive circuit 17, and an actuator 18. System 14 operates using the actuator 18 to control the position of a plunger in a syringe pump. The processor 21 will also control the actuator 18 to actuate any plunger described herein. For example, the actuator 18 may be coupled to the shaft 19 (described below) in Figure 3 to control the position of a plunger 20.

[0071] The control system 16 includes a processor 21 connected to memory 22. The processor 21 and memory 22 may be connected together via serial connection, parallel connection, memory bus, or other data communication link. The processor 21 may include one or more cores, may use any instruction set, and / or may use any instruction set architecture or microarchitecture. For example, the processor 21 may have a von Neumann architecture, a Harvard architecture, may be a microcontroller, and may use the MIPS instruction set, RISC instruction set, and / or CISC instruction set, or others.

[0072] The control system 16 includes a treatment layer 23 and a control layer 24. The treatment layer 23 can instruct the control layer 24 on when and how much liquid has been discharged from the syringe pump 10. For example, the treatment layer 23 may instruct the control layer 24 to discharge 10 millimeters of liquid per minute. The treatment layer 23 can also control the stop and start times of liquid delivery to the patient. For example, the treatment layer 23 may include a time-based liquid delivery rate profile. The treatment layer 23 can instruct the control layer 24 on the liquid discharge rate as a value within the liquid delivery rate profile, indicating the time over which the delivery rate changes. The control layer 24 receives the target liquid discharge rate from the treatment layer 23 and uses this target liquid discharge rate as a setpoint in the control loop, controlling the position of the actuator 18 to reach the setpoint. For example, the control layer 24 may implement a proportional-integral-derivative ("PID") control algorithm, which has an output to the drive circuit 17 and feedback from one or more sensors 15, such as a piston position sensor 25 and / or a volume sensor 26. In various embodiments, the control layer 24 may have a target discharge rate, a target volume to discharge, a target residual liquid volume, or any combination thereof.

[0073] The treatment layer 23 and the control layer 24 can be implemented in hardware, software, software executed on the processor 21, firmware, microcode, assembly, virtualization, bytecode, VHDL, Verilog, within a PLD, within a CPLD, etc., or any combination thereof. For example, the treatment layer 23 and / or the control layer 24 can be stored in memory 22 as a set of operations of processor 21 executable commands configured to run on one or more processors 21. Memory 22 may be volatile memory, non-volatile memory, hard disk, magnetic storage, flash storage, EEPROM, ROM, optical memory, other non-transient processor-readable media, etc., or any combination thereof.

[0074] The control system 16 outputs one or more signals to a drive circuit 17 that drives the actuator 18. The drive circuit 17 may include power MOSFETs, voltage converters, power converters, and / or additional circuits that receive commands from the control system 16, and apply one or more sufficient signals to the actuator 18. When the actuator 18 is actuated, the sensor 15 is used by the control system 16 as feedback, including a piston position sensor 25 and / or a volume sensor 26. The piston position sensor 25 may be a linear position sensor and may be used with any position sensor described herein. The volume sensor 26 may, in some embodiments, be an acoustic volume sensing ("AVS") sensor, which is used with a speaker, reference microphone, and variable volume microphone (of any sufficient syringe pump described herein) to estimate the amount of liquid discharged or contained in the reservoir. In some embodiments, one of sensors 25 and 26 may be used, both may be used, and / or neither may be used.

[0075] Figure 3 illustrates a syringe pump 27 having a reference volume assembly 28 connected to a reservoir 29 of the syringe pump 27 for acoustically estimating the amount of liquid discharged by the syringe pump 27 according to embodiments of the present disclosure. The syringe pump 27 uses acoustic volume sensing ("AVS") to estimate the volume of liquid in the liquid side 31 of the reservoir 29, and / or estimates the amount of liquid discharged from the liquid side 32 of the reservoir 29 using a speaker 6, a reference microphone 37, and a variable volume microphone 38.

[0076] The syringe pump includes a reservoir 29 and a plunger 20. The plunger includes a shaft 19 and a piston 30, the piston of which slides with the inner surface of the reservoir 29. The shaft 19 passes through a reference volume assembly 28 via a seal 41. The piston 30 defines a liquid side 31 and a non-liquid side 32. As the piston 30 moves toward the port 33, the liquid is discharged through the port 33. The piston 30 may include one or more seals 34 arranged around its periphery, providing sufficient liquid seal between the liquid side 31 and the non-liquid side 32 of the reservoir 29. The port 33 may be connected to a needle, tube, manifold, and / or may include a connector, such as a screw-type thread formed thereon.

[0077] The reference volume assembly 28 includes a reference volume 35. The reference volume 35 may have a small laser perforation to the outside air, and is designed to fill with air as the piston 30 moves. The reference volume assembly 28 also includes a speaker 36, a reference microphone 37, and a variable volume microphone 38. The speaker 36 generates sound waves that are applied to the reference volume 35. The term “sound waves” may include waves at frequencies perceptible to humans, frequencies not perceptible to humans, frequencies not perceptible to biological organs, ultrasonic frequencies, acoustic frequencies, or other frequencies of mechanical vibration. The sound waves propagate to the variable volume 40 through the acoustic port 39. The reference microphone 37 detects sound waves in the reference volume 35, and the variable volume microphone 38 detects sound waves in the variable volume 40. A processor, for example, the processor 21 in Figure 2, is operationally communicating with the speaker 36 and the reference and variable volume microphones 37 and 38. The processor 21 instructs the speaker 36 to generate multiple acoustic frequencies and measures the magnitude and / or phase of the sound waves detected by the reference microphone 37 and the variable volume microphone 38. The acoustic response can correlate with the volume of the variable volume 40; for example, the resonant frequency may correlate with the volume of the variable volume 40. The processor can estimate the volume of liquid 31 remaining in the liquid side 31 of the reservoir 29 by subtracting from a predetermined total volume of the reservoir 29 (1) the volume of the variable volume 40 (as measured from the acoustic response), (2) the volume displaced by the piston 30, and (3) the volume of the shaft located inside the reservoir 29.

[0078] The processor 21 may estimate the fluid volume during the first sweep using the speaker 36, reference microphone 37, and variable volume microphone 38. The processor 21 may then move the shaft 19 (via the actuator) to perform a second sweep. The processor 21 may compare the two volumes to determine the amount of liquid discharged through the port 33 during the activation of the actuator connected to the shaft 19.

[0079] Figure 4 illustrates a syringe pump 42 having two reservoirs 43 and 44 and a reference volume assembly 45 connected to the reservoirs 43 and 44, for acoustically estimating the amount of liquid discharged by the syringe pump 42 according to an embodiment of the present disclosure. The syringe pump 42 can use acoustic volume sensing ("AVS") to estimate the volume of liquid in the liquid side 55 of reservoir 43, the volume of liquid in the liquid side 56 of reservoir 44, the volume of liquid discharged from the liquid side 55 of reservoir 43, and / or the volume of liquid discharged from the liquid side 56 of reservoir 44, using a speaker 51, a reference microphone 52, a variable volume microphone 54, and a variable volume microphone 53.

[0080] The syringe pump 42 includes reservoirs 43 and 44, which may be attachable to and / or detachable from the syringe pump 42. For example, reservoirs 43 and 44 may be pre-loaded into a housing 69 and snap into place, or reservoirs 43 and 44 may snap into a reference volume assembly 45. In some embodiments, the syringe pump 42 selectively includes a housing 69 and a cap 70. The housing 69 may be attachable to the cap 70, and / or the housing 69 may be attachable to other caps.

[0081] The syringe pump 42 includes a reference volume assembly 45, which has a reference volume chamber 46 acoustically coupled to the non-liquid sides 47 and 48 of two reservoirs 43 and 44, respectively. The reference volume chamber 46 is coupled to the non-liquid side 47 of reservoir 43 via an acoustic port 49, and the reference volume chamber 46 is coupled to the non-liquid side 48 of reservoir 44 via a port 50.

[0082] The reference volume chamber 46 includes a speaker 51 and a reference microphone 52, both of which are coupled to the processor 21 in Figure 2. The reference volume assembly 45 also includes a variable volume microphone 53 configured to detect sound waves in the non-liquid side 48 of the reservoir 44, and another variable volume microphone 54 configured to detect sound waves in the non-liquid side 47 of the reservoir 43. The two variable volume microphones 53 and 54 are coupled to the processor 21 in Figure 2. The processor 21 will account for the volumes of the shafts 57 and 58 and the pistons 59 and 60.

[0083] The syringe pump 42 also includes a manifold 61, which is connected to ports 62 and 63 of the reservoirs 43 and 44, respectively, and provides a liquid path to a discharge port 64. The manifold 61 may be reattachable and / or disposable. The discharge port 64 may be connected to a needle 65, tubing (not shown), fittings (not shown), and / or may include any known connector or port. The needle 65 may be attachable and / or disposable.

[0084] In Figure 2, the processor 21 uses a speaker 51 to generate multiple acoustic frequencies, which are received by a reference microphone 52 and variable volume microphones 53 and 54. The processor 21 uses the acoustic responses of the non-liquid sides 47 and 48 to estimate their respective volumes. These two values ​​are used by the processor 21 to estimate the volumes of the liquid sides 55 and 56 of the two storage containers 43 and 44.

[0085] Figure 5 illustrates a syringe pump 66 having two reservoirs 67 and 68 arranged within an acoustic housing 71, and a reference volume assembly 29 coupled to the acoustic housing 71, for acoustically estimating the volume of liquid discharged by the syringe pump 66 according to an embodiment of the present disclosure. The syringe pump 66 uses acoustic volume sensing ("AVS") to estimate the volume of liquid in reservoir 67, the volume of liquid in reservoir 68, the volume of liquid discharged from reservoir 67, and / or the volume of liquid discharged from reservoir 68, using a speaker 36, a reference microphone 37, and a variable volume microphone 81. The acoustic housing 71 may be attachable and / or disposable. For example, the acoustic housing 71 may snap into a housing 88. The housing 88 may be reusable and / or disposable. The manifold 61 and / or needle 109 may be attachable and / or disposable. The protective screen 72 prevents debris from entering and / or affecting the acoustic port 39.

[0086] The syringe pump 66 includes reservoirs 67 and 68 located within the acoustic housing 71. The reservoir 67 includes the piston 75 of the plunger 73 located inside it. The reservoir 76 includes the piston 76 of the plunger 74 located inside it. The reservoir 67 has a stopper 145 attached to its end to prevent the piston 75 from coming out of the reservoir 67. Furthermore, the storage unit 68 has a stopper 146 attached to its end to prevent the piston 76 from exiting the storage unit 68.

[0087] Plunger 73 includes a shaft 77, and plunger 74 includes a shaft 78 that is fully housed within the acoustic housing 71. Furthermore, one actuator 79 is coupled to shaft 77 to drive shaft 77, and the other actuator 80 is coupled to shaft 78 to drive this shaft 78. Both actuators 79 and 80 and the two shafts 77 and 78 are housed within the acoustic housing 71 in the embodiment shown in Figure 5. Since shafts 77 and 78 and actuators 79 and 80 are housed within the acoustic housing 71, the movement of shafts 77 and 78 and actuators 79 and 80 does not affect the volume detected by the processor 21 in Figure 2 (via a variable volume microphone 81 housed within the acoustic housing 71) as the liquid is discharged. Therefore, in the embodiment shown in Figure 5, the processor 21 in Figure 2 does not need to compensate for the variable volume resulting from the movement of shafts 77 and 80 and / or actuators 79 and 80.

[0088] Figure 6 illustrates an injection pump 82, which, according to embodiments of the present disclosure, has two reservoirs 83 and 84, each located within an acoustic housing (85 and 86), and a reference volume assembly 87 acoustically coupled to the acoustic housings 85 and 86, for acoustically estimating the volume of liquid discharged by the syringe pump 82. The syringe pump 82 estimates the volume of liquid in reservoir 83, the volume of liquid in reservoir 84, the volume of liquid discharged from reservoir 83, and / or the volume of liquid discharged from reservoir 84 using acoustic volume sensing ("AVS"), a speaker 36, a reference microphone 37, a variable volume microphone 53, and a variable volume microphone 54. The acoustic housings 85 and 86 may be removable, attachable, permanently attached to a housing 89, and / or snap-fit ​​to the housing 89. In addition to or instead of the above, the reservoirs 83 and 84 may be removable, attachable, disposable, and / or snap-fit ​​into the housing 89. The manifold 61 and needle 109 may be attachable and / or removable. The syringe pump 82 includes an actuator 90 coupled to the shaft 91, which drives the shaft 91. Since the actuators 90 and 93 of the plunger 93 are located within the acoustic housing 85, the processor 21 in Figure 2 does not need to consider the movement of the shaft 91 and / or the actuator 90. The syringe pump 82 also includes an actuator 92 coupled to the shaft 94, which actsuates the shaft 94. Similarly, if the actuator 92 of the plunger 95 and the shaft 95 are located within the acoustic housing 86, the processor 21 in Figure 2 does not need to consider the movement of the shaft 94 and the actuator 92. The reference volume assembly 87 is coupled to the acoustic housing 85 via one acoustic port 96 and to the acoustic housing 86 via the other acoustic port 97.

[0089] Figure 7 illustrates a syringe pump 98, which, according to an embodiment of the present disclosure, has two reservoirs 99 and 100 and two volume sensors 101 and 102, each connected to a plunger 103 and 104 of each reservoir (99 and 199, respectively) for estimating the amount of liquid discharged by the syringe pump 98. The syringe pump 98 includes an actuator 90 coupled to the shaft of the plunger 103 to drive the plunger 103. Furthermore, the syringe pump 98 includes an actuator 92 coupled to the shaft of the plunger 104 to drive the plunger 104.

[0090] The processor 21 in Figure 2 is coupled to the capacity sensors 101 and 102 and can determine the linear positions of the plungers 103 and 104 to estimate the volume remaining in the storage containers 99 and 100. For example, the processor 21 models the reservoir as a cylinder, and feedback from volume sensors 101 and 102 can tell how the positions of the pistons 105 and 106 of the plungers 103 and 104 correspond, respectively. That is, the positions of pistons 15 and 106 can be used to estimate the volume of liquid in reservoirs 99 and 100, respectively, by modeling the liquid side of piston 105 as a cylinder.

[0091] The syringe pump 98 also includes a housing 107, which may be removable from a non-disposable housing 108 and / or disposable. In addition to or instead of the housing 108, the syringe pump 98 also includes a manifold 153, which may be removable from a non-disposable housing 108 and / or disposable. The syringe pump 98 may optionally also include a needle 109 coupled to the manifold 108. This needle 109 may be removable and / or disposable.

[0092] Figure 8 illustrates a syringe pump 110, which, according to an embodiment of the present disclosure, has two reservoirs 111 and 112 and two optical targets 113 and 114, each coupled to a plunger 118 and 119 of each reservoir (111 and 112, respectively), for estimating the amount of liquid discharged by the syringe pump 110 using an optical ranging assembly 115. The syringe pump 110 includes a housing 154, which may be attachable to and / or detachable (e.g., disposable) with respect to an outer housing 155. In addition to or instead, the reservoirs 111 and 112 may be attachable to and / or detachable (and disposable) with respect to the housing 154. The manifold 153 and / or needle 109 may be attachable, detachable, and / or disposable.

[0093] The syringe pump 110 includes an actuator 90 connected to the shaft of the plunger 118 to drive the plunger 118. Furthermore, the syringe pump 110 includes an actuator 92 coupled to the shaft of the plunger 119 to drive the plunger 119.

[0094] The processor 21 in Figure 2 can estimate the amount of liquid in the reservoirs 111 and 112 in a manner similar to that shown in the embodiment of Figure 7. The optical ranging assembly includes two illuminators / sensors 116 and 117. Illuminator / sensor 116 illuminates an optical target 113, which is reflected back to the illuminator / sensor 116. The optical ranging assembly 115 can estimate the position of plunger 118 using time of flight and / or intensity. Similarly, illuminator / sensor 117 illuminates an optical target 114, which is reflected back to the illuminator / sensor 117. The optical ranging assembly 115 can estimate the position of plunger 119 using time of flight and / or received intensity.

[0095] The light from the illuminators / sensors 116 and 117 may be from LEDs, or it may be infrared, visible light, or invisible light, and may be adjusted for purposes such as power saving.

[0096] Figure 9 illustrates a syringe pump 120, which, according to embodiments of the present disclosure, has two reservoirs 121 and 122 and two light sources 123 and 124, each coupled to the respective plungers 126 and 127 of each reservoir (121 and 122, respectively) for use with an optical ranging assembly 125 to estimate the amount of liquid discharged by the syringe pump. The syringe pump 120 includes a housing 156, which may be attachable to and / or detachable (e.g., disposable) with respect to an outer housing 157. In addition to or instead of this, the reservoirs 121 and 122 may be attachable to and / or detachable (and may also be disposable) with respect to the housing 156. The manifold 153 and / or needle 109 may be attachable, detachable, and / or disposable. The syringe pump 120 includes an actuator 90 coupled to the shaft of the plunger 126 to drive the plunger 126. The syringe pump 120 also includes an actuator 92 coupled to the shaft of the plunger 127, which drives the plunger 127.

[0097] The optical ranging assembly 126 includes sensors 128 and 160. Sensors 128 and 160 measure the intensity of light sources 123 and 124 (e.g., LEDs), and this measured intensity correlates to the positions of plungers 126 and 127. The processor 21 may modulate the light sources 123 and 124 so that only one of the light sources 123 and 124 is active during the measurement period of each sensor 128 and 160. In one embodiment, one of the light sources 123 and 124 may be active while both sensors 128 and 160 are used to estimate the position of their respective plungers (of plungers 126 and 127).

[0098] Figure 10 illustrates a syringe pump 129, which, according to embodiments of the present disclosure, comprises two reservoirs 130 and 131 and two linear optical position sensors 132 and 133, each connected to the respective plungers (i.e., 134 and 135, respectively) of the respective reservoirs (i.e., 130 and 131, respectively) for estimating the amount of liquid discharged by the syringe pump 129.

[0099] The syringe pump 129 includes a housing 158, which may be attachable to and / or detachable (e.g., disposable) from the outer housing 159. In addition to or instead of this, the storage containers 130 and 131 may be attachable to and / or detachable (and may also be disposable) from the housing 158. The manifold 153 and / or needle 109 may be attachable, detachable, and / or disposable.

[0100] The linear optical position sensors 132 and 133 can be linear optical encoders. The processor 21 in Figure 2 uses feedback from the linear optical position sensors 132 and 133 to estimate the amount of liquid in each of the reservoirs 130 and 131, for example, by cylinder volume approximation or other geometric approximation.

[0101] Figures 11-12 show a flowchart of a method 136 for estimating liquid delivery according to embodiments of the present disclosure. This method 136 may be used with any of the pumps disclosed herein, for example, syringe pump 10 in Figure 1, syringe pump 27 in Figure 3, syringe pump 42 in Figure 4, syringe pump 66 in Figure 5, syringe pump 82 in Figure 6, syringe pump 98 in Figure 7, syringe pump 110 in Figure 8, syringe pump 120 in Figure 9, and / or syringe pump 129 in Figure 10.

[0102] Action 137 places the pump plunger in the first position. Action 138 generates a sound wave. Action 139 applies the sound wave to the reference chamber. Action 140 transmits the sound wave to the non-liquid side of the pump reservoir. Action 141 detects the sound wave in the reference chamber. Action 142 detects the sound wave on the non-liquid side of the pump reservoir. Action 143 compares the detected sound wave in the reference chamber with the detected sound wave on the liquid side of the reservoir to determine the first volume of liquid on the liquid side of the reservoir. Action 144 drives the pump plunger to the second position. Action 147 applies the sound wave to the reference chamber. Action 148 applies the sound wave to the non-liquid side of the pump reservoir. Action 149 detects the sound wave in the reference chamber. Action 150 detects the sound wave on the non-liquid side of the pump reservoir. Action 151 compares the sound waves detected in the reference chamber with the sound waves detected in the non-liquid side of the reservoir to determine the second volume of liquid in the liquid side of the reservoir. Action 152 compares the first volume with the second volume to measure the amount of liquid discharged. Acoustic volume detection

[0103] The following description describes acoustic volume sensing, which can be performed by the processor 21 in Figure 2, using a speaker and two microphones (e.g., a reference microphone and a variable volume microphone) of a syringe pump, such as syringe pump 27 in Figure 3, syringe pump 42 in Figure 3, syringe pump 66 in Figure 5, and / or syringe pump 82 in Figure 6. AVS can be used to estimate the liquid in the reservoir disclosed herein, estimate the liquid discharged from the reservoir disclosed herein, and / or estimate the liquid discharge rate of the reservoir disclosed herein. Table 1 shows the definitions of various conditions as follows: [Table 1]

[0104] The Acoustic Volume Sensor ("AVS") measures the volume of liquid displaced by the non-liquid side of an AVS chamber, such as an acoustic housing or a storage container. This sensor does not directly measure the liquid volume, but instead measures the variable volume V2 of air within the AVS chamber. If the total volume of the AVS chamber remains constant, the change in V2 is the exact opposite of the change in liquid volume. The AVS chamber is the volume of air in fluid communication with a variable volume microphone beyond the acoustic port. For example, in Figure 3, the non-liquid side 32 of the storage container 29 is a variable volume, and the reference volume 35 is V1.

[0105] The volume of air V2 is measured using acoustic resonance. A time-varying pressure is established in a constant volume V1 of a reference chamber using a speaker. This pressure perturbation causes a periodic airflow at the acoustic port connecting the two volumes, which in turn causes a pressure perturbation in the variable volume. The system dynamics are analogous to those of a Helmholtz oscillator, where the two volumes together act as an "elastic" force, and the air at the port connecting the volumes acts as a resonant mass. The natural frequency of this resonance is a function of the port geometry, the speed of sound, and the variable volume. Since the port geometry is constant and the speed of sound is found by measuring the temperature, given these two parameters, the variable volume can be found from the natural frequency. In some embodiments of this disclosure, a temperature sensor is used within the acoustic housing and / or on the non-liquid side of the storage container. In some embodiments, the temperature is considered to be a predetermined constant value, for example, room temperature, or the like.

[0106] The natural frequency of the system is estimated by measuring the relative response of pressure in two volumes to different frequency perturbations formed by a speaker. A typical AVS measurement consists of making an initial measurement. The liquid is then released from the liquid side of one or more reservoirs and delivered to the patient (after which a second volume determination is made). The difference between these measurements is the volume of liquid delivered to the patient. In some embodiments, the measurement is made before the liquid side of one or more reservoirs is filled and / or before the liquid is discharged to detect any malfunction in the fluid system, for example, when a syringe pump is pre-loaded.

[0107] AVS measurement may occur through the following actions: (1) the processor 21 turns on the power to the AVS electronics, enables the ADC of the processor 21 in Figure 2, and initializes the AVS algorithm; (2) the AVS measurement consists of collecting data at several different frequencies; (3) selectively measuring the temperature; and (4) then running an evaluation routine based on the collected data to estimate the volume of liquid on the liquid side of the storage container.

[0108] To collect data at each frequency, the speaker is driven sinusoidally at the target frequency, and measurements are taken over integer wavelengths from two microphones, for example, a reference microphone and a variable volume microphone (as described above). Once the data is collected, the processor 21 in Figure 1 performs a discrete Fourier transform algorithm on the data to convert the time-series data from the microphones into a single complex amplitude. Integrity checks are performed on the data from the microphones to determine whether the data is valid, for example, whether the resonance is within a predetermined phase and / or acoustic frequency.

[0109] Frequency measurements are performed at several different frequencies. This sinusoidal sweep is used by an estimation routine to estimate the variable volume. After the estimation is complete, other integrity checks may be performed on all sinusoidal sweeps, including a secondary check by processor 21 in Figure 2.

[0110] In one embodiment, after the processor 21 in Figure 2 confirms the completeness of the measurement, the volume estimation is completed and the sensor is powered off.

[0111] AVS Resonance Model

[0112] The governing equations for the AVS system can be derived from the first principle, given several simplified assumptions. This system is modeled as two linearized acoustic volumes connected by an idealized acoustic port.

[0113] Acoustic volume modeling

[0114] The pressure and volume of an ideal adiabatic gas can be related by Equation 1 as follows:

[0115]

number

[0116] Here, K is a constant defined by the initial conditions of the system. Equation 1 can be rewritten as shown in Equation 2, using the mean pressure P, volume V, and terms for small time-dependent perturbations at the peaks of these pressures p(t) and v(t).

[0117]

number

[0118] Differentiating equation 2 yields equation 3, as shown below.

[0119]

number

[0120] Equation 3 can be simplified to the following Equation 4.

[0121]

number

[0122] If the acoustic pressure level is significantly lower than the ambient pressure, Equation 4 can be further simplified to Equation 5 as follows.

[0123]

number

[0124] Using an adiabatic relationship, equation 6 can be shown as follows.

[0125]

number

[0126] Therefore, the error assumption is given by Equation 7 as follows.

[0127]

number

[0128] A very large acoustic signal (e.g., 120 dB) corresponds to a pressure sine wave with an amplitude of approximately 20 Pascals. Assuming that air in atmospheric conditions has parameters γ=1.4 and P=101325 Pa, the resulting error is 0.03%. The conversion from dB to Pa is given by Equation 8 below.

[0129]

number

[0130] Here, P ref = 20 μPa.

[0131] Applying the ideal gas law P=ρRT and substituting the pressure, we obtain the result shown in Equation 9 below.

[0132]

number

[0133] This can be expressed in the term for the speed of sound in Equation 10 as follows:

[0134]

number

[0135] Substituting equation 9 into equation 10 yields equation 11 as follows.

[0136]

number

[0137] The acoustic impedance with respect to volume is defined by Equation 12 as follows:

[0138]

number

[0139] Acoustic port modeling

[0140] The acoustic port is modeled assuming that all fluid within the port essentially moves as a rigid cylinder reciprocating axially. It is assumed that all fluid within the channel moves at the same velocity, that the channel has a steady cross-section, and that terminal effects arising from fluid entering and leaving the channel are ignored.

[0141] form

number

number

[0142] The quadratic differential equation can describe the dynamics of the fluid in the channel, as shown in Equation 13 below.

[0143]

number

[0144] Alternatively, the volumetric flow rate term is shown in Equation 14 as follows:

[0145]

number

[0146] The acoustic impedance of a channel can be described as shown in Equation 15.

[0147]

number

[0148] System migration function

[0149] If port dynamics are defined using volume as described above, the AVS system can be described by the following system in Equations 16-19.

[0150]

number

[0151]

number

[0152]

number

[0153]

number

[0154] Process p0 as input,

number

[0155]

number

[0156]

number

[0157]

number

[0158] The relationship between the two volumes on each side of an acoustic port is called the cross-port movement function. This relationship is shown in Equation 23 below.

[0159]

number

[0160] Here

number

number

[0161] This relationship has the advantage that the poles depend only on the variable volume and not on the reference volume. Note that the resonance peak is actually caused by the inversion of zero in the reference volume pressure response. This means that pressure measurements in the reference chamber have low amplitude near the resonance, which can affect noise in the measurement.

[0162] Resonance Q factor and peak response

[0163] The sound quality of a resonance is the ratio of the conserved energy to the product of the power loss and the resonant frequency. For a purely second-order system, the sound quality factor can be expressed as a function of the damping ratio shown in Equation 24.

[0164]

number

[0165] The ratio of the peak response to the low-frequency response can also be described as a function of the damping ratio shown in Equation 25.

[0166]

number

[0167] This is the damped natural frequency.

number

[0168] Electrical and mechanical similarities

[0169] An acoustic resonator is similar to either a spring-mass-damper system or an LRC circuit, for example, a resistor, inductor, and capacitor connected together in series.

[0170] Calculation of complex response

[0171] To perform AVS, the system must obtain the relative responses of two microphones to an acoustic wave set by a speaker. This is achieved by driving the speaker with a sinusoidal output at a known frequency, and then the complex response of each microphone is found at its driving frequency. Finally, the relative responses of the two microphones are found and modified to alternate the sampling of the analog-to-digital converter coupled to processor 21 in Figure 2.

[0172] Furthermore, the total signal difference is calculated and compared to the difference of pure tones extracted using the Discrete Fourier Transform ("DFT"). This provides a measurement of how much signal power is coming from the noise source or distortion. In some embodiments of this disclosure, this value can be used to reject and repeat poor measurements.

[0173] Calculation of the Discrete Fourier Transform

[0174] The signals from each microphone are sampled in sync with the output to the speaker, and a certain number of points (N) are collected for each wavelength. The signals measured at each point at each wavelength are summed over integers of the wavelength M, and after all the data for that frequency has been collected, it is stored in array x by the interrupt processing routine ("ISR") in the processor 21 in Figure 2.

[0175] The Discrete Fourier Transform is performed on the data at integer values ​​corresponding to the speaker's driving frequency. The general expression for the first harmonic of the DFT is given by Equation 26 below.

[0176]

number

[0177] The product MN is the total number of points, and when multiples of 2 are added, the resulting real and imaginary parts of the answer are equivalent to the amplitude of the sine wave shown in Equation 27.

[0178]

number

[0179] The real part of this expression is shown in Equation 28.

[0180]

number

[0181] To reduce the number of calculations required to compute the DFT, the symmetry of the cosine function can be utilized. The above expression is equivalent to Equation 29, as follows:

[0182]

number

[0183] Similarly, the imaginary part of the expression is shown in Equation 30 as follows.

[0184]

number

[0185]

number

[0186] The difference in the signal at that driving frequency is shown in Equation 32 below.

[0187]

number

[0188] The tone difference is proportional to the acoustic output at the driving frequency. The maximum possible values ​​of the real and imaginary parts of x are 2 11 This corresponds to half of the A / D range. The value of the tone difference is 2 21This is half the square of the A / D range.

[0189] Calculation of total signal difference

[0190] A good measure of measurement integrity is the ratio of the acoustic power at the driving frequency to the total acoustic power at all frequencies. The total signal difference is given by the expression in Equation 33.

[0191]

number

[0192] However, in certain embodiments, weighting is performed in an A / D interrupt service routine (ISR), which is subject to time constraints and / or must store all microphone data for post-processing. In certain embodiments, to increase efficiency, the false difference is calculated based on a single averaged wavelength. The false difference of the signal is calculated using the following relationship shown in Equation 34:

[0193]

number

[0194] The results are in units of the total number of ADs per square. The weighting is for a 12-bit ADC.

number

number

[0195] Calculation of relative microphone response

[0196] Next, the relative response G of the two microphones is calculated from the complex responses of the individual microphones shown in equations 35-37.

[0197]

number

[0198]

number

[0199]

number

[0200] The denominators of all these expressions are calculated in the previous section and can be expressed as a reference tone difference term shown in Equation 38 as follows:

[0201]

number

[0202] Correction for A / D distortion

[0203] Speaker output can be updated 32 times per sample at a constant rate. For example, as the drive frequency changes, the speaker output frequency is also updated to maintain a constant 32 cycles. Two microphones are sampled synchronously with the speaker output, and the sampling frequency remains at a constant interval of the drive frequency. However, the microphone A / D measurements are not sampled simultaneously, and the A / D ISR alternates between the two microphones, taking the sum of N samples per wavelength for each microphone. The result is a phase offset of π / N between the two microphones. To correct this phase offset, complex rotation is applied to the relative frequency response calculated in the previous section.

[0204] To rotate the angle π / N by a complex number, it is multiplied by the following equation.

Equation

[0205]

Equation

[0206] Time delay

[0207] In one embodiment, when deriving the AVS equation, one of the assumptions is that the pressure is uniform in the volume of the sound. This assumption is true if the acoustic wavelength is large compared to the dimensions of the AVS chamber. The wavelength of a sound wave at a given frequency can be calculated by the following Equation 40:

[0208]

Equation

[0209] For example, the wavelength is approximately 246 mm at 1 kHz and approximately 49.2 mm at 5 kHz. The AVS chamber has a diameter, and the time delay associated with the acoustic waves traveling through the volume is small, but it has a measurable effect. This effect can be modeled as a time delay (or a time advance dependent on microphone orientation). The Laplace transform of the pure time delay d is given by Equation 41 below.

[0210]

number

[0211] The phase is affected by the time delay, not the magnitude of the system response. To correct for the time delay, the frequency response data can be pre-corrected by applying a model fitting algorithm. The complex amplitude can be rotated as a function of frequency according to the time delay formula described above. Since the time delay can be considered fixed, the rotation is only a function of frequency.

[0212] Time delays can be determined by running optimization routines, and finding these delays can minimize model fitting errors. In addition to or instead of this, there may be apparent "time advances" in the data. For example, a reference microphone may experience slight pressure perturbations in front of the acoustic port, and a variable microphone may experience slight pressure perturbations behind the acoustic port. These "advances" and "delays" may be due to the propagation of pressure waves, which are added to the system's "resonance" dynamics, and these effects can be explained, for example.

[0213] Amplitude smoothing

[0214] The amplitude of pressure measurements for a given speaker drive signal may vary from device to device and is a function of the drive frequency. This device-to-device variation stems from part-to-part differences in microphone and speaker sensitivity (e.g., approximately + / - 3dB). Frequency-based attributes arise not only from the expected dynamics of acoustic resonance but also from changes in speaker sensitivity across frequencies.

[0215] To compensate, in one embodiment, the speaker gain is automatically adjusted during the AVS measurement period. The speaker gain is stored in an array with one input for each sinusoidal sweep frequency, for example, in memory 22 in Figure 2. The amplitude of the microphone signal (from a variable or reference microphone) can be compared against a target amplitude. If it is too large or too small, a binary lookup routine can be used to update the speaker gain at that frequency.

[0216] Checking the integrity of individual measurements

[0217] Component errors, malfunctions, or external interference can lead to inaccurate measurements. Component failures may include distorted speaker output or a faulty microphone. External interferences may include mechanical shock to the pump housing or very high levels of external noise. These types of malfunctions can be detected using two different integrity checks: microphone saturation and out-of-band difference.

[0218] The microphone saturation check refers to the maximum and minimum wavelength-averaged signals to each microphone. If these values ​​are near the A / D limit, then a flag in the processor 21 in Figure 2 is set to indicate that the measured amplitude is out of range.

[0219] Out-of-band difference checking compares the tone difference to the total signal difference for each microphone. In the ideal case where the ratio of these signals is 1, all acoustic power is at the drive frequency. In the case of an impact or very large external acoustic noise, more power exists at other frequencies and this value is lower than 1. In certain embodiments, normal operation may be considered to have a ratio greater than 0.99.

[0220] In certain embodiments, if an individual data point fails any of these integrity checks, it can be repeated or removed without having to repeat all sine sweeps to assist in promoting AVS robustness. Other integrity checks may be based on a complete sine sweep, which will be described later.

[0221] Volume evaluation using the swept sine general solution method

[0222] The resonance frequency of the system can be estimated using swept sine system identification. In this method, the response of the system to a sine wave pressure change may be found at several different frequencies. This frequency response data may then be used to estimate the system transfer function using linear regression.

[0223] The transfer function for the system can be expressed as a rational function of s. In the general case, the transfer function is represented as follows by an nth-order numerator and an mth-order denominator. N and D are the coefficients for the numerator and denominator, respectively. The equation is normalized so that the leading coefficient in the denominator is 1, as shown in Equations 42 and 43.

[0224]

Number

[0225] Alternatively,

[0226]

Number

[0227] This equation can be rewritten in the form of equation 44 as follows:

[0228]

number

[0229] Equation 45 shows this sum in matrix notation.

[0230]

number

[0231] Here, k is the number of data points collected on the swept sine. To simplify the notation, this equation can be simplified using the vector y shown in Equation 46.

[0232]

number

[0233] Here, y is k × 1, x is k × (m + n - 1), and c is (m + n - 1) × 1. The coefficients can then be found using the least squares method. The error function can be written as shown in Equation 47.

[0234]

number

[0235] The function to be minimized is the weighted square of the error function, and as shown in equations 48-49, W is a k × k diagonal matrix.

[0236]

number

[0237]

number

[0238] As shown in equations 50-52, the two central terms are scalars, so the transpose matrix can be ignored.

[0239]

number

[0240]

number

[0241]

number

[0242] In one embodiment, the complex transpose matrix is ​​used for all of these cases. This attempt yields complex coefficients, but this process can be modified to ensure that all coefficients are real. If the error function is changed to Equation 53, the least squares minimization can be modified to yield only real coefficients.

[0243]

number

[0244] Next, the coefficients can be found using Equation 54.

[0245]

number

[0246] Volume evaluation using the sweep-sine method for quadratic systems

[0247] For systems with a zero-order numerator and a second-order denominator, the transfer function is shown in Equation 55.

[0248]

number

[0249] The coefficients in this transfer function can be found as follows (Equation 56) based on the expression found in the previous section.

[0250]

number

[0251] Here, equation 57 is as follows:

[0252]

number

[0253] To simplify the algorithm, several terms can be combined, as shown in equations 58-60:

[0254]

number

[0255] Here,

[0256]

number

[0257]

number

[0258] To find the equation for D with respect to the complex response vector G and the natural frequency s=jω, X was first divided into its real and imaginary parts, as shown in equations 61 and 62, respectively.

[0259]

number

[0260] The real and imaginary parts of the expression for D described above are then given by equations 63 and 64, respectively.

[0261]

number

[0262] Combining these terms gives the final expression for matrix D. This matrix contains only real values, as shown in equation 65 below.

[0263]

number

[0264] A similar attempt can be made to find the expression for the vector b in the terms of G and ω. The real and imaginary parts of y are shown in equations 66-67. The real and imaginary parts of y are illustrated in equations on pages 66-67.

[0265]

number

[0266] Combining these two means that we are given an expression for vector b shown in equation 68, as follows.

number

[0267] The next step is to inverse matrix D. Since this matrix is ​​symmetric and positive determinant, the number of calculations required to find the inverse is reduced from that of the general 3x3 case. The general expression for the inverse matrix is ​​given in Equation 69.

[0268]

number

[0269] If D is expressed as in equation 70,

[0270]

number

[0271] The adjoint matrix can then be written as Equation 71, as follows:

[0272]

number

[0273] Due to symmetry, only the diagonal matrix above needs to be calculated. Then, this determinant can be calculated using the adjoint matrix value term, and the advantage of zero elements in the initial array can be taken, as shown in Equation 72 below.

[0274]

number

[0275] Finally, the inverse of D can be written in the form shown in equation 73.

[0276]

number

[0277] In one embodiment, the value in Equation 74 can be solved.

[0278]

number

[0279] Therefore, equation (75) is used.

[0280]

number

[0281] To obtain a quantitative assessment of how well the data fits the model, an initial expression for the error, such as that given in Equation 76, is used.

[0282]

number

[0283] This can be described in terms of the matrix D and vectors b and c shown in Equation 77.

[0284]

number

[0285] Here,

[0286]

number

[0287]

number

[0288] In one embodiment, to compare errors from different sinusoidal sweeps, the fitted error is normalized by the square of a matrix weight as shown in Equation 80 below, where h is a scalar.

[0289]

number

[0290] Volume estimation using swept sinusoidal volume estimation

[0291] Model fitting may be used to extract the resonant frequency of a port from sine sweep data. The delivered volume may be related to this value. The ideal relationship between the two can be expressed by the relationship shown in Equation 81.

[0292]

number

[0293] Since the speed of sound changes with temperature, it is beneficial to separate the temperature effect externally, as shown in Equation 82.

[0294]

number

[0295] Next, this volume can be expressed as a function of the measured resonant frequency and temperature, as shown in Equation 83 below.

[0296]

number

[0297] Here, C is the calibration constant shown in Equation 84 as follows.

[0298]

number

[0299] Sweep sinusoidal volume estimation using sweep sinusoidal volume completeness check

[0300] In one embodiment, a second set of integrity checks can be performed on the output of the mode fitting and volume estimation routine (the first set of checks is performed at the FFT level). The checks can be performed either through redundancy or through range checks on several values, such as (1) model fitting error, (2) estimated damping ratio, (3) estimated transfer function gain, (4) estimated natural frequency, (5) estimated variable volume, and (6) AVS sensor temperature.

[0301] Furthermore, in certain embodiments, the AVS calculation portion of the processor 21 in Figure 2 can be made redundant using an independent temperature sensor and an independent copy of calibration parameters to protect against RAM failure.

[0302] Volume estimation using sweeping sinusoidal disposable detection

[0303] In certain embodiments, the presence of disposable products, such as attachable cartridges or storage devices, can be detected using magnetic switches and mechanical interlocking devices. However, a second detection method may be used to 1) identify pumps and chargers attached to disposable products, and 2) provide a backup to the primary detection method.

[0304] If disposable products don't exist, then the variable volume V2 is practically very large. As a result, there is a normal signal from the reference microphone, but only a very weak signal from the variable microphone. If the average amplitude of the reference microphone is normal during the sinusoidal sweep period (which confirms that the speaker is working) and the average amplitude of the variable microphone is small, then the flag of the processor 21 in Figure 2 is set to indicate that no disposable products are present.

[0305] Details of the implementation of sizing V1 for V2

[0306] Sizing V1 may include the cancellation of acoustic volume due to the relative positions of poles and zero in the transfer function. The transfer functions for both V1 and V2 are given below for speaker volume replacement, as shown in equations 85-88.

[0307]

number

[0308]

number

[0309] Here,

[0310]

number

[0311] As V1 increases, the gain decreases, and the speaker must be driven with a higher amplitude to obtain the same sound pressure level. However, increasing V1 has the advantage of shifting the complex zero in the p1 transfer function toward the complex pole. In the limited case, where V1→∞, then α→1, and there is pole zero cancellation and a flat response. Thus, increasing V1 has a decrease in both resonance and notch in the p1 transfer function, and the p2 pole ω n Moving toward this point, the result is low sensitivity to measurement error when calculating the p2 / p1 transfer function.

[0312] Implementation Details - Aliasing

[0313] Higher frequencies can be aliased down to the target frequency. The alias frequency can be expressed by equation 89 as follows:

[0314]

number

[0315] Here, f s is the sampling frequency, f n is the frequency of the noise source, n is a positive integer, and f is the alias frequency of the noise source.

[0316] The demodulation routine can remove noise except at specific frequencies of demodulation. If the sample frequency is dynamically set to a certain multiple of the demodulation frequency, then the frequencies of the noise that can alias down to the demodulation frequency will be a fixed set of harmonics of its fundamental frequency.

[0317] For example, if the sampling frequency is 8 times the demodulation frequency, then the noise frequencies that can alias down to that frequency are

[0318]

Number

[0319] Here

Number

[0320]

Number

[0321] Avs Measurement Error Source - AVS Chamber Movement

[0322] In one embodiment, one of the assumptions of AVS measurement is that the total AVS volume (V2 plus the volume taken by other components) is constant. However, if the AVS housing bends, the total volume of the AVS chamber may change slightly and affect the differential volume measurement. In one embodiment, to maintain the volume contribution, the error is kept below 1.0% of the fluid delivery.

[0323] AVS measurement error source - external noise

[0324] In one embodiment, external noise sources can be eliminated.

[0325] Amount of measurement error source - Mechanical shock

[0326] Mechanical shocks to the pump housing during the AVS measurement period can affect microphone measurements and lead to errors in frequency response data. However, these errors can be detected using out-of-band difference checks in the demodulation routine of processor 21 shown in Figure 2. If such errors are detected, the data points can be repeated with little impact on the AVS measurement (e.g., another sample is taken).

[0327] AVS measurement error source - Air in the AVS chamber

[0328] The mechanism behind bubbles affecting AVS measurements is due to secondary resonance. This secondary resonance is of the fourth order of the system, and if estimations use a second-order model, it can cause some errors depending on the frequency and magnitude of the secondary resonance.

[0329] Source of AVS measurement error - electrical component malfunction

[0330] Generally, electrical component malfunctions result in no signal or increased high harmonic distortion. In either case, the malfunction is detected by an AVS integrity check or measurement invalidation.

[0331] One exception that has been identified is a malfunction in the oscillator used to control the DAC and ADC. If this oscillator drifts out of tolerance, it will induce measurement errors that cannot be detected by low-level integrity checks (which in extreme cases can be detected by the volume integrity check described above). To protect against these malfunctions, in one embodiment, the oscillator is matched with an independent clock whenever AVS measurement is initiated. A first aspect of the present invention is: It is a pump, A storage container configured to deliver liquid, A port connected to the storage container and configured to discharge the liquid, A plunger having a piston coupled to a shaft, wherein the piston is positioned within the reservoir so as to slide-engage with the inner surface of the reservoir, and the piston defines the liquid side and the non-liquid side of the reservoir, so that the movement of the plunger toward the liquid side of the reservoir discharges liquid through the port. The storage unit comprises a reference volume assembly coupled to the storage unit, the reference volume assembly is A reference volume chamber that is acoustically in communication with the non-liquid side of the storage container, A speaker placed inside the aforementioned reference volume chamber, The pump includes a reference microphone placed within the reference volume chamber. A second aspect of the present invention is: In the pump of the first embodiment, the reference volume assembly is a pump that is coupled to the storage at the end of the storage opposite to the port of the storage. A third aspect of the present invention is: A pump according to the first embodiment further comprises a variable volume microphone disposed within the storage container and configured to detect sound waves within the storage container. A fourth aspect of the present invention is: A pump according to the first embodiment further comprises a variable volume microphone positioned in the reference volume assembly and configured to detect sound waves within the reservoir. A fifth aspect of the present invention is: It is a pump, A storage container configured to deliver liquid, A port connected to the storage container and configured to discharge the liquid, A plunger having a piston coupled to a shaft, wherein the piston is positioned within the reservoir so as to slide-engage with the inner surface of the reservoir, and the piston defines the liquid side and the non-liquid side of the reservoir, so that the movement of the plunger toward the liquid side of the reservoir discharges liquid through the port. A further storage container configured to deliver further liquid, A further port is coupled to the further storage and configured to discharge the further liquid, A further plunger having a further piston coupled to a further shaft, the further piston being positioned within the further reservoir so as to slide-engage with the inner surface of the further reservoir, the further piston defining the liquid side and the non-liquid side of the further reservoir, the further plunger's movement toward the liquid side of the further reservoir discharges liquid through the further port, The storage container is further equipped with a reference volume assembly coupled to the storage container at the opposite end of the storage container to the port, the reference volume assembly being coupled to the further storage container at the opposite end of the further storage container to the further port, and the reference volume assembly is A reference volume chamber that acoustically communicates with the non-liquid side of the storage container, and this reference volume chamber further comprises a reference volume chamber that acoustically communicates with the non-liquid side of the further storage container, and a speaker disposed within the reference volume chamber. The pump includes a reference microphone placed within the reference volume chamber. A sixth aspect of the present invention is: In the fifth embodiment of the pump, at least one of the first and second reservoirs is a pump that can be attached to the reference volume assembly. A seventh aspect of the present invention is: The pump of the fifth embodiment further comprises a manifold, which manifold is A first connector port connected to the aforementioned port, A second connector port connected to the aforementioned further port, Discharge port, The pump includes a liquid path that fluidly connects the first and second connector ports together to the discharge port. An eighth aspect of the present invention is: In the seventh embodiment of the pump, the manifold is a pump that can be attached to the first and second connector ports. A ninth aspect of the present invention is: A fifth embodiment of the pump further comprises a variable volume microphone disposed within the storage container and configured to detect sound waves within the storage container. A tenth aspect of the present invention is: A pump according to a ninth embodiment further comprises a further variable volume microphone disposed within the further storage container and configured to detect sound waves within the further storage container. An eleventh aspect of the present invention is: A fifth embodiment of the pump further comprises a variable volume microphone positioned in the reference volume assembly and configured to detect sound waves within the reservoir. A twelfth aspect of the present invention is: A pump according to an eleventh embodiment further comprises a further variable volume microphone positioned in the reference volume assembly and configured to detect sound waves in the further reservoir. A thirteenth aspect of the present invention is: It is a pump, Acoustic housing and A storage container configured to deliver liquid and located within the acoustic housing, A port connected to the storage container and configured to discharge the liquid, A plunger having a piston coupled to a shaft, wherein the piston is positioned within the reservoir so as to slide-engage with the inner surface of the reservoir, and the piston defines the liquid side and the non-liquid side of the reservoir, so that the movement of the plunger toward the liquid side of the reservoir discharges liquid through the port. The acoustic housing is coupled to a reference volume assembly via an acoustic port, and the reference volume assembly is A reference volume chamber that is acoustically in communication with the acoustic housing via the acoustic port, and a speaker disposed within the reference volume chamber, The pump includes a reference microphone placed within the reference volume chamber. A fourteenth aspect of the present invention is: A pump according to the 13th embodiment further comprises an actuator coupled to the shaft and driving the plunger. A fifteenth aspect of the present invention is: In the pump according to the 14th embodiment, the actuator is located within the acoustic housing. A sixteenth aspect of the present invention is: The pump of the 13th embodiment further, A further reservoir configured to deliver additional liquid and located within the acoustic housing, A further port is coupled to the further storage and configured to discharge the further liquid, A pump comprising a further plunger having a further piston coupled to a further shaft and disposed within the acoustic housing, wherein the further piston is disposed within the further reservoir so as to slide-engage with the inner surface of the further reservoir, and the further piston defines the liquid side and the non-liquid side of the further reservoir, the movement of the further plunger toward the liquid side of the further reservoir causes the liquid to be discharged through the further port. A 17th aspect of the present invention is: A pump according to the 16th embodiment further comprises a manifold, the manifold being: A first connector port connected to the aforementioned port, A second connector port connected to the aforementioned further port, Discharge port, The pump includes a liquid path that fluidly connects the first and second connector ports together to the discharge port. An eighteenth aspect of the present invention is: In the pump of the 17th embodiment, the manifold is a pump that can be attached to the first and second connector ports. A 19th aspect of the present invention is: It is a pump, Acoustic housing and Further acoustic housing and A storage container configured to deliver liquid and located within the acoustic housing, A port connected to the storage container and configured to discharge the liquid, A plunger having a piston coupled to a shaft and positioned within the acoustic housing, wherein the piston is positioned within the reservoir so as to slide-engage with the inner surface of the reservoir, and the piston defines the liquid side and the non-liquid side of the reservoir, so that the movement of the plunger toward the liquid side of the reservoir discharges liquid through the port, A further reservoir configured to deliver further liquid and located within the further acoustic housing, A further port is coupled to the further storage container and configured to discharge the further liquid, A further plunger having a further piston coupled to a further shaft, disposed within the further acoustic housing, wherein the further piston is disposed within the further reservoir so as to slide-engage with the inner surface of the further reservoir, and the further piston defines the liquid side and the non-liquid side of the further reservoir, so that the movement of the further plunger toward the liquid side of the further reservoir causes the liquid to be discharged through the further port of the further plunger. The reference volume assembly comprises a reference volume assembly connected to the acoustic housing through an acoustic port and further connected to the further acoustic housing through a further acoustic port, the reference volume assembly A reference volume chamber that is acoustically in communication with the acoustic housing via the acoustic port and acoustically in communication with the further acoustic housing via the further acoustic port, A speaker placed inside the aforementioned reference volume chamber, The pump includes a reference microphone placed within the reference volume chamber. A 20th aspect of the present invention is: A pump according to the 19th embodiment further comprises an actuator coupled to the shaft and driving the plunger. A 21st aspect of the present invention is: In the 20th embodiment of the pump, the actuator is located within the acoustic housing. A 22nd aspect of the present invention is: A pump according to a 19th embodiment further comprises a further actuator coupled to the further shaft and driving the further plunger. A 23rd aspect of the present invention is: A pump according to a 20th embodiment, wherein the actuator is located within the acoustic housing, and the further actuator is located within the further acoustic housing. A 24th aspect of the present invention is: A pump according to the 19th embodiment further comprises a manifold, the manifold being A first connector port connected to the aforementioned port, A second connector port connected to the aforementioned further port, Discharge port, The pump includes a liquid path that fluidly connects the first and second connector ports together to the discharge port. A 25th aspect of the present invention is: In the pump of the 24th embodiment, the manifold is a pump that can be attached to first and second connector ports. A 26th aspect of the present invention is: It is a pump, A storage container configured to deliver liquid, A port connected to the storage container and configured to discharge the liquid, A plunger having a piston coupled to a shaft, wherein the piston is positioned within the reservoir so as to slide-engage with the inner surface of the reservoir, and the piston defines the liquid side and the non-liquid side of the reservoir, so that the movement of the plunger toward the liquid side of the reservoir discharges liquid through the port. The pump comprises a linear position sensor configured to detect the position of the shaft. A 27th aspect of the present invention is: A pump according to the 26th embodiment, further comprising a housing, wherein the reservoir is located within the housing, and the plunger is located within the housing. A 28th aspect of the present invention is: A pump according to the 26th embodiment further comprises an actuator coupled to the shaft and driving the plunger. A 29th aspect of the present invention is: A pump according to the 28th embodiment further comprises a housing, wherein the actuator is located within the housing. A 30th aspect of the present invention is: In the 26th embodiment of the pump, the pump further comprises a housing, wherein the linear position sensor is located within the housing. A 31st aspect of the present invention is: In a pump according to the 26th embodiment, A further storage container configured to deliver further liquid, A further port is coupled to the further storage and configured to discharge the further liquid, A further plunger having a further piston coupled to a further shaft, the further piston being positioned within the further reservoir so as to slide-engage with the inner surface of the further reservoir, the further piston defining the liquid side and the non-liquid side of the further reservoir, the further plunger's movement toward the liquid side of the further reservoir discharges liquid through the further port, The pump comprises a further linear position sensor configured to detect the position of the further shaft. A 32nd aspect of the present invention is: A pump according to the 31st embodiment further comprises a manifold, the manifold being A first connector port connected to the aforementioned port, A second connector port connected to the aforementioned further port, Discharge port, The pump includes a liquid path that fluidly connects the first and second connector ports together to the discharge port. A 33rd aspect of the present invention is: In the pump of the 32nd embodiment, the manifold is a pump that can be attached to the first and second connector ports. A 34th aspect of the present invention is: A pump according to the 31st embodiment, further comprising a housing, wherein the reservoir and the further reservoir are located within the housing, and the plunger and the further reservoir are located within the housing. A 35th aspect of the present invention is: In a pump according to the 31st embodiment, An actuator coupled to the shaft and driving the plunger, The pump further comprises a further actuator coupled to the further shaft and driving the further plunger. A 36th aspect of the present invention is: A pump according to the 35th embodiment, wherein the actuator and the further actuator are located within the housing. A 37th aspect of the present invention is: A pump according to the 31st embodiment further comprises a housing, wherein the linear position sensor and the further linear position sensor are disposed within the housing. A 38th aspect of the present invention is: In the pump of the 26th embodiment, the linear position sensor is a capacitive sensor coupled to the shaft. A 39th aspect of the present invention is: In the pump of the 26th embodiment, the linear position sensor is a linear optical sensor coupled to the shaft. A forty-th aspect of the present invention is: In the pump according to the 26th embodiment, the linear position sensor is An optical target coupled to the shaft, The pump includes an optical ranging assembly configured to estimate the linear position of the shaft by determining the range of the optical target. A forty-first aspect of the present invention is: In a pump according to the 40th embodiment, the optical target is a reflective target, and the optical distance measuring assembly includes an illuminator configured to determine the linear position of the shaft from the reflection of the illumination of the reflective target by illuminating the reflective target. A 42nd aspect of the present invention is: In the pump of the fortyth embodiment, the optical target is a light source, and the optical distance measuring assembly is configured to determine the linear position of the shaft from the measured intensity of the light source measured by the optical distance measuring assembly. A forty-third aspect of the present invention is: In a pump according to any one of the first to forty-two embodiments, the piston is a pump that includes a seal arranged around the piston. A 44th aspect of the present invention is: In the pump described in any one of the first to forty-two embodiments, the storage container is cylindrical, thus defining a circular cross-section, and the piston engages with the inner surface of the storage container along the circular cross-section. A forty-fifth aspect of the present invention is, In the pump described in any one of the first to forty-two embodiments, the storage container is cubic in shape, thus defining a rectangular cross-section, and the piston engages with the inner surface of the storage container along the rectangular cross-section. A forty-sixth aspect of the present invention is: A pump according to any one of the first to forty-two embodiments, further comprising a vent that is in fluid communication with the non-liquid side of the storage container. A forty-seventh aspect of the present invention is: In the pump of the 44th embodiment, the vent is further configured to acoustically seal the non-liquid side of the reservoir from the outside of the reservoir. A forty-eighth aspect of the present invention is: A pump according to any one of the first to forty-two embodiments, further comprising a one-way valve that fluidly communicates with the non-liquid side of the storage container, wherein the one-way valve is configured to introduce gas from the outside of the storage container into the non-liquid side of the storage container. A 49th aspect of the present invention is: In a pump according to any one of the first to forty-two embodiments, the plunger is movable between a fully discharged position and a fully loaded position, and the reference volume chamber is in fluid communication with the non-liquid side of the reservoir when the plunger is in either the fully discharged position or the fully loaded position. A 50th aspect of the present invention is: In a pump according to any one of the first to twelfth embodiments or the twenty-sixth embodiment, the reference volume chamber includes a conduit configured to house the shaft, the shaft slidingly engaging with the conduit. A 51st aspect of the present invention is: A pump according to the 50th embodiment, wherein the conduit houses the shaft and acoustically seals the non-liquid side of the reservoir as the shaft engages with the conduit. A 52nd aspect of the present invention is: In a pump according to any one of the first to twelfth embodiments, the reference volume assembly further includes an acoustic port that acoustically communicates with the volume chamber and the non-liquid side of the storage container. A 53rd aspect of the present invention is: A pump according to any one of the first to eighth embodiments or the thirteenth to twenty-fifth embodiments, further comprising a variable volume microphone, wherein the non-liquid side of the reservoir is configured to house the variable volume microphone within the inner surface of the reservoir, and the variable volume microphone is configured to detect sound waves within the non-liquid side of the reservoir. A 54th aspect of the present invention is: A pump according to any one of the first to eighth embodiments or the thirteenth to twenty-fifth embodiments, further comprising a variable volume microphone attached to the reference volume assembly, wherein the variable volume microphone is configured to detect sound waves in the non-liquid side of the reservoir. A 55th aspect of the present invention is: In a pump according to any one of the embodiments of the 14th, 15th, 20th to 23rd, 28th, 29th, 35th, or 36th, the actuator is a pump in which the actuator is one of a linear actuator, a screw-type linear actuator, a linear track actuator, a linear servo, a linear stepper motor, or a linear motor. A 56th aspect of the present invention is: A system for estimating liquid delivery, A pump according to the first embodiment, An actuator coupled to the shaft, A linear position sensor is coupled to the shaft and configured to detect the position of the shaft, The system comprises a processor coupled in conjunction with the actuator and the linear position sensor, and configured to estimate the volume of the discharged liquid as a function of the position of the shaft. A 57th aspect of the present invention is: A system for estimating liquid delivery, A pump of the 13th embodiment, An actuator coupled to the shaft, A linear position sensor is coupled to the shaft and configured to detect the position of the shaft, The system comprises a processor coupled in conjunction with the actuator and the linear position sensor, and configured to estimate the volume of the discharged liquid as a function of the position of the shaft. A 58th aspect of the present invention is: A system for estimating liquid delivery, A pump according to the 19th embodiment, An actuator coupled to the shaft, A linear position sensor is coupled to the shaft and configured to detect the position of the shaft, The system comprises a processor coupled in conjunction with the actuator and the linear position sensor, and configured to estimate the volume of the discharged liquid as a function of the position of the shaft. Fifty-nine aspects of the present invention are: A system for estimating liquid delivery, A pump according to the 26th embodiment, An actuator coupled to the shaft, A linear position sensor is coupled to the shaft and configured to detect the position of the shaft, The system comprises a processor coupled in conjunction with the actuator and the linear position sensor, and configured to estimate the volume of the discharged liquid as a function of the position of the shaft. A 60th aspect of the present invention is: A system for estimating liquid delivery, A pump according to the first embodiment, A variable volume microphone configured and positioned to detect sound waves within the non-liquid side of the storage container, The system comprises a speaker and a processor coupled in conjunction with the reference and variable volume microphones, the processor being configured to instruct the speaker to generate a plurality of acoustic frequencies and to estimate the volume of the discharged liquid as a function of acoustic feedback from the variable volume and reference microphones. A 61st aspect of the present invention is: A system for estimating liquid delivery, A fifth embodiment of the pump, A variable volume microphone configured and positioned to detect sound waves within the non-liquid side of the storage container, The system comprises a speaker and a processor coupled in conjunction with the reference and variable volume microphones, the processor being configured to instruct the speaker to generate a plurality of acoustic frequencies and to estimate the volume of the discharged liquid as a function of acoustic feedback from the variable volume and reference microphones. A 62nd aspect of the present invention is: A system for estimating liquid delivery, A pump of the 13th embodiment, A variable volume microphone configured and positioned to detect sound waves within the non-liquid side of the storage container, The system comprises a speaker and a processor coupled in conjunction with the reference and variable volume microphones, the processor being configured to instruct the speaker to generate a plurality of acoustic frequencies and to estimate the volume of the discharged liquid as a function of acoustic feedback from the variable volume and reference microphones. A 63rd aspect of the present invention is: A system for estimating liquid delivery, A pump according to the 19th embodiment, A variable volume microphone configured and positioned to detect sound waves within the non-liquid side of the storage container, The system comprises a speaker and a processor coupled in conjunction with the reference and variable volume microphones, the processor being configured to instruct the speaker to generate a plurality of acoustic frequencies and to estimate the volume of the discharged liquid as a function of acoustic feedback from the variable volume and reference microphones. A 64th aspect of the present invention is: A method for estimating liquid delivery, Position the pump plunger to the first position, Generate sound waves, Apply sound waves to the reference chamber, The sound waves are transmitted to the non-liquid side of the pump's reservoir. The sound waves in the reference chamber are detected, The sound waves in the non-liquid side of the storage container of the pump are detected. The sound waves detected in the reference chamber are compared with the sound waves detected on the non-liquid side of the storage container to determine the first volume of liquid in the liquid side of the storage container. The plunger of the pump is driven to the second position, The sound waves detected in the reference chamber are compared with the sound waves detected on the non-liquid side of the storage container to determine the second volume of liquid in the liquid side of the storage container. The method includes comparing a first volume with a second volume to determine the amount of liquid discharged. A 65th aspect of the present invention is: A system for preparing a syringe pump, A monitoring client configured to communicate prescription orders via a user interface, A pharmacy computer that operates in communication with the monitoring client to receive the prescription order, A compounding robot configured to receive prescription orders from the pharmacy computer and to dispense the prescription into at least one liquid corresponding to the prescription order, A syringe pump configured to contain at least one liquid corresponding to the aforementioned prescription order, The system comprises a data download device configured to download the aforementioned prescription order into the memory of a tablet dispenser. A 66th aspect of the present invention is: In the system of the 65th embodiment, the syringe pump is a system including a reference volume attached thereto. A 67th aspect of the present invention is: In the system of the 65th embodiment, the compounding robot is a system for filling the syringe pump with the at least one liquid. A 68th aspect of the present invention is: In the system of the 65th embodiment, the compounding robot operates in communication with the data download device, and the compounding robot instructs the data download device to download the prescription order into the memory of the tablet dispenser. A 69th aspect of the present invention is: In the system of the 65th embodiment, the data download device is a system that receives prescription orders from at least one of the compounding robot and the pharmacy computer. A 70th aspect of the present invention is: Any and all features of novelty of syringes described, referenced, illustrated, or depicted herein are any and all of the above. A 71st aspect of the present invention is: This is essentially the device shown and described.

Claims

1. It is a pump, A storage container configured to deliver liquid, A port connected to the storage container and configured to discharge the liquid, A plunger having a piston coupled to a shaft, wherein the piston is positioned within the reservoir so as to slide-engage with the inner surface of the reservoir, and the piston defines the liquid side and the non-liquid side of the reservoir, so that the movement of the plunger toward the liquid side of the reservoir discharges liquid through the port. The system includes a linear position sensor configured to detect the position of the shaft, pump.

2. The device further comprises a housing, wherein the storage container is located within the housing, and the plunger is located within the housing. The pump according to claim 1.

3. The system further comprises an actuator coupled to the shaft and driving the plunger. The pump according to claim 1.

4. The device further comprises a housing, and the actuator is located within the housing. The pump according to claim 3.

5. The housing is further comprising the linear position sensor, which is located within the housing. The pump according to claim 1.

6. A further storage container configured to deliver further liquid, A further port is coupled to the further storage and configured to discharge the further liquid, A further plunger having a further piston coupled to a further shaft, the further piston being positioned within the further reservoir so as to slide-engage with the inner surface of the further reservoir, the further piston defining the liquid side and the non-liquid side of the further reservoir, the further plunger's movement toward the liquid side of the further reservoir discharges liquid through the further port, The system further includes a linear position sensor configured to detect the position of the further shaft, The pump according to claim 1.

7. It also has a manifold, and this manifold is, A first connector port connected to the aforementioned port, A second connector port connected to the aforementioned further port, Discharge port, The device includes a liquid path that fluidly connects the first and second connector ports together to the discharge port, The pump according to claim 6.

8. The manifold can be attached to the first and second connector ports. The pump according to claim 7.

9. The present invention further comprises a housing, wherein the storage container and the further storage container are located within the housing, and the plunger and the further storage container are located within the housing. The pump according to claim 6.

10. An actuator coupled to the shaft and driving the plunger, The system further comprises a further actuator coupled to the further shaft and driving the further plunger, The pump according to claim 6.

11. The device further comprises a housing, wherein the actuator and the further actuator are located within the housing. The pump according to claim 10.

12. The system further comprises a housing, wherein the linear position sensor and the further linear position sensor are located within the housing. The pump according to claim 6.

13. The linear position sensor is a capacitive sensor coupled to the shaft. The pump according to claim 1.

14. The linear position sensor is a linear optical sensor coupled to the shaft. The pump according to claim 1.

15. The linear position sensor is An optical target coupled to the shaft, By determining the range of the optical target, the linear position of the shaft is estimated. A system comprising an optical ranging assembly configured as follows: The pump according to claim 1.

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