Device for controlling fluid flow

Abstract

The present invention relates to devices for controlling fluid flow. A device, system, and method for regulating fluid flow are disclosed. The device includes a curved, elongated support member that is elastically deformable and has a first end and a second end. The device also includes an opposing support member configured to position a tube against the curved, elongated support member between the first end and the second end. Deformation of the curved, elongated support member caused by movement of the first end and the second end toward one another reduces an internal volume of the tube.

Description

[0001] This application is a divisional application of patent application number 202010316738.4, filed on April 21, 2020, entitled "Apparatus for Controlling Fluid Flow". Patent application number 202010316738.4, entitled "Apparatus for Controlling Fluid Flow", is a divisional application of patent application number 201710443206.5, filed on June 13, 2017, entitled "Apparatus for Controlling Fluid Flow". And patent application number 201710443206.5, entitled "Apparatus for Controlling Fluid Flow", is a divisional application of patent application number 201280069373.3 (PCT / US2012 / 071142), filed on August 8, 2014, with an international filing date of December 21, 2012, entitled "Apparatus for Controlling Fluid Flow".

[0002] Cross-references to related applications

[0003] This application is a non-provisional international application filed under the Patent Cooperation Treaty, claiming priority from the following applications:

[0004] U.S. Provisional Patent Application No. 61 / 578,649, filed on December 21, 2011, entitled “System, Method, and Apparatus for Infusing Fluid” (Accounting Firm No. J02);

[0005] U.S. Provisional Patent Application No. 61 / 578,658, filed on December 21, 2011, entitled "System, Method, and Apparatus for Estimating Liquid Delivery" (Accounting Firm No. J04);

[0006] U.S. Provisional Patent Application No. 61 / 578,674, filed on December 21, 2011, entitled “System, Method, and Apparatus for Dispensing Oral Medications” (Office File No. J05);

[0007] U.S. Provisional Patent Application No. 61 / 651,322 (Representative Office File No. J46), filed May 24, 2012, entitled "System, Method, and Apparatus for Electronic Patient Care"; and

[0008] U.S. Provisional Patent Application No. 61 / 679,117 (Accounting Firm No. J30), filed August 3, 2012, entitled “System, Method, and Apparatus for Monitoring, Regulating, or Controlling Fluid Flow,” is incorporated herein by reference in its entirety.

[0009] This application claims priority to the following applications and is also a continuation of the following applications:

[0010] U.S. Patent Application No. 13 / 333,574, filed on December 21, 2011, entitled "System, Method, and Apparatus for Electronic Patient Care," was now published on July 19, 2012, as U.S. Publication No. US-2012-0185267-A1 (Agency File No. I97).

[0011] PCT application No. PCT / US11 / 66588 (file number I97WO), filed on December 21, 2011, entitled “System, Method, and Apparatus for Electronic Patient Care,” is incorporated herein by reference in its entirety.

[0012] This application may also relate to one or more of the following patent applications filed on the same date, which are hereby incorporated herein by reference in their entirety:

[0013] The non-provisional application for “System, Method, and Apparatus for Clamping” (Case No. J47, Agency);

[0014] The non-provisional application for “System, Method, and Apparatus for Dispensing Oral Medications” (Case No. J74, Agency);

[0015] The PCT application for “System, Method, and Apparatus for Dispensing Oral Medications” (Case No. J74WO);

[0016] The non-provisional application for “System, Method, and Apparatus for Estimating Liquid Delivery” (Case No. J75, Agency);

[0017] The non-provisional application for “System, Method, and Apparatus for Infusing Fluid” (Case No. J76, Agent's Office);

[0018] The PCT application for “System, Method, and Apparatus for Infusing Fluid” (Case No. J76WO);

[0019] The non-provisional application for “System, Method, and Apparatus for Electronic Patient Care” (Case No. J77, Agency);

[0020] The non-provisional application for “System, Method, and Apparatus for Electronic Patient Care” (Case No. J78, Agency);

[0021] A non-provisional application for “System, Method, and Apparatus for Monitoring, Regulating, or Controlling Fluid Flow” (Case No. J79, Agency);

[0022] The non-provisional application for “System, Method, and Apparatus for Estimating Liquid Delivery” (Case No. J81, Agency);

[0023] The PCT application for “System, Method, and Apparatus for Estimating Liquid Delivery” (Case File No. J81WO); and

[0024] The non-provisional application for “System, Method, and Apparatus for Electronic Patient Care” (Case No. J85). Technical Field

[0025] This disclosure relates to monitoring, regulating, or controlling fluid flow. More specifically, this disclosure relates to a system, method, and apparatus for monitoring, regulating, or controlling fluid flow, for use in medical applications such as intravenous therapy, dialysis, blood transfusion therapy, peritoneal injection therapy, bolus delivery, enteral nutrition therapy, parenteral nutrition therapy, hemoperfusion therapy, fluid resuscitation therapy, or insulin delivery. Background Technology

[0026] In many medical settings, a common pattern of medical treatment involves the delivery of fluids to patients, such as humans, animals, or pets. There may be a need to administer fluids rapidly, precisely, or slowly. Saline and lactated Ringer's solution are examples of commonly used fluids. Such fluids can be used to maintain or raise blood pressure and to promote adequate perfusion. In traumatic shock settings or septic shock, fluid resuscitation is often the primary treatment for maintaining or raising blood pressure.

[0027] Fluid delivery to a patient can be facilitated by using a gravity-fed feeding line (or tubing) inserted into the patient's body. Typically, a fluid reservoir (e.g., an IV bag) hangs on a pole and is connected to the fluid tubing. The fluid tubing is often coupled to the infusion chamber to trap air and estimate fluid flow. Below the fluid tubing may be a manually actuated valve to regulate fluid flow. For example, by counting the number of drops formed in the infusion chamber over a period of time, the caregiver can calculate the rate of fluid flow through the infusion chamber and adjust the valve (if necessary) to achieve the desired flow rate.

[0028] For certain treatments, fluid delivery systems must strictly adhere to flow rates set by the caregiver. Typically, such applications use infusion pumps, but in all cases or environments, such pumps may not be necessary. Summary of the Invention

[0029] In brief and general, this disclosure relates to a system, method, and apparatus for monitoring, regulating, or controlling fluid flow, for use in medical applications such as intravenous therapy, dialysis, blood transfusion therapy, peritoneal injection therapy, bolus delivery, enteral nutrition therapy, parenteral nutrition therapy, hemoperfusion therapy, fluid resuscitation therapy, or insulin delivery. More specifically, this disclosure relates to a fluid flow meter for monitoring the flow of patient-associated fluids, a valve for regulating the flow of patient-associated fluids, and / or a fluid flow meter coupled to a valve (e.g., arranged in a closed-loop, open-loop, or feedback configuration) to monitor, regulate, and / or control the use of patient-associated fluids.

[0030] In some embodiments of this disclosure, the flow meter includes one or more optical sensors to monitor the flow of fluid within the tube, for example, using an image sensor to monitor droplets within a drip chamber attached to the tube. The flow meter can be a standalone device, can be used in conjunction with a pump or valve, or both, and / or can be used to provide feedback to any electronic device. The flow meter can be remotely controlled, for example, via a monitoring client, a telecommander, a smartphone, a computer, etc. The flow meter can measure average flow rate, instantaneous flow rate, droplet volume, droplet growth rate, or other parameters related to fluid flow.

[0031] The flow meter can use flow rate or parameters related to fluid flow to: (1) display the flow rate or parameters on a screen, (2) provide feedback (wirelessly or via wire) to an injection pump such as a peristaltic pump, such as the flow rate or parameters related to fluid flow, (3) provide feedback to a monitoring client such as a smartphone or a remote monitoring client, (4) issue a warning when the flow rate or parameters related to fluid flow are outside a predetermined range, (5) issue a warning when the flow rate or parameters related to fluid flow are above a predetermined threshold, (6) issue a warning when free flow is detected, (7) transmit the warning to the pump, the monitoring client, or the remote monitoring client, (8) issue a warning when free flow is detected, and / or instruct the valve to stop the fluid flow when the flow rate or parameters related to fluid flow are above a threshold or outside a predetermined range, and / or (9) broadcast the flow rate or parameters related to fluid flow.

[0032] In some embodiments described herein, the valve regulates the flow of fluid associated with a patient. The valves disclosed herein may be manually actuated or actuated by an actuator (or both). The valve may be used with or without a pump, with or without a flow meter, and / or may be a standalone device. The valve may be remotely controlled, for example, via a monitoring client, telecommander, smartphone, computer, etc. The valve may compress a portion of the tubing that is substantially larger than the diameter of the pipe (e.g., more than 2, 5, 10 times, etc.).

[0033] The valve may consist of two or more parts that compress the tube, or it may consist of a single part that compresses the tube when the single part moves or deforms. The two or more parts and / or the single part may be manufactured using injection molding, ultrasonic welding, gluing, or molding of multiple parts together, etc. Each of the two or more parts consists of one or more sub-components that can be permanently or temporarily attached to each other. A single part may be manufactured from one or more sub-components that are permanently or temporarily coupled together, for example, using ultrasonic welding, gluing, locking, or other techniques. These parts may be made of plastic, metal, alloy, polymer, or other materials.

[0034] In some embodiments of this disclosure, a flow meter is coupled to a valve to regulate fluid flow, such as fluid flow into a patient's body. The flow meter coupled to the valve can be used in place of a pump (such as a peristaltic infusion pump), or can be a replacement for an infusion pump. The flow meter and valve combination can be remotely controlled or monitored, for example, via a monitoring client, a telecommand, a smartphone, a computer, etc. The monitoring client can control the flow meter or valve, can be a repeater between the flow meter and valve, can monitor the operation of the flow meter or valve, can transmit information related to the flow meter or valve to a server, and / or may not be used in the system.

[0035] Flow meters can monitor fluid flow and directly or indirectly regulate valves or pumps (e.g., syringe pumps). When a flow meter detects a free-flowing condition, it can trigger an alarm, determine if the flow rate exceeds a predetermined threshold or is outside a predetermined range, and / or detect any abnormal behavior. In response to an alarm or condition, the flow meter can cause the flow meter to stop fluid flow, instruct a valve to stop fluid flow, instruct a safety valve to stop fluid flow, notify a monitoring client or remote communicator, broadcast the detected condition, or execute a predefined routine or algorithm.

[0036] In some embodiments of this disclosure, the device for regulating fluid flow includes a curved, elongated support member and an opposing support member. The curved, elongated support member is elastically deformable and has a first end and a second end. The opposing support member is configured to position a tube against the curved, elongated support member between the first end and the second end, such that deformation of the curved, elongated support member caused by movement of the first end and the second end toward each other reduces the internal volume of the tube. The opposing support member may be another curved, elongated support member.

[0037] The device may include an actuator coupled to a bent, elongated support member to deform the member by moving a first end and a second end toward each other through actuation of the actuator. In some such embodiments, the actuator may be a lead screw, and a knob may be coupled to the lead screw to drive it.

[0038] An actuator, a curved elongated support member, and an opposing support member can be configured to regulate fluid flow according to a Gompertz curve via actuation of the actuator. In some embodiments, the actuator can be further configured to actuate the first and second ends toward each other along a predetermined portion of the Gompertz curve. For example, the actuator can be actuated only along a portion of the actuable range of the curved elongated support member and the opposing support member.

[0039] The actuator, the curved elongated support member, and the opposing support member can be configured to regulate the fluid flow according to an S-curve by actuation of the actuator. The actuator can be further configured to actuate the first end and the second end toward each other along a predetermined portion of the S-curve.

[0040] The slender, curved support member can be semi-rigid and / or can be made of substantially stretchable material. The slender, curved support member can be arc-shaped, slender, and / or C-shaped.

[0041] The device may further include an elongated connecting member operatively coupled to a first end and a second end of a curved elongated support member.

[0042] In some embodiments of this disclosure, the device may include an actuator coupled to an elongated connecting member and a bent elongated support member to apply an outward expansion force so as to deform a first end and a second end of the bent elongated support member toward each other.

[0043] In some embodiments of this disclosure, a curved elongated support member is arranged to be approximately parallel to another curved elongated support member along most of its length. For example, a curved elongated support member defines a length, and another curved elongated support member defines a length, and the length of the other curved elongated support member is arranged to be approximately parallel to the length of the curved elongated support member.

[0044] In some embodiments of this disclosure, the device includes an actuator operatively coupled at a first end and a second end to a curved elongated support member, and connected at the first end and a second end to another curved elongated support member. Actuation of the actuator causes the first and second ends of the curved elongated support member to approach each other and also causes the first and second ends of the other curved elongated support member to approach each other, thereby causing a reduction in the distance between the curved elongated support member and the other curved elongated support member to thereby compress the tube.

[0045] In some embodiments of this disclosure, a curved, elongated support member defines a length, and an opposing support member is arranged to be orthogonal to it along a portion of that length.

[0046] In some embodiments of this disclosure, the curved elongated support member includes a plurality of ridges disposed thereon to engage the tube.

[0047] In some embodiments of this disclosure, the opposing support member includes a plurality of ridges disposed thereon to engage the tube.

[0048] In some embodiments of this disclosure, the curved elongated support member includes a flange extending from its length, the flange being configured to retain a tube. An opposing support member may include another flange extending from its length, the other flange being configured to retain a tube, such that the flanges are approximately parallel to each other and approximately parallel to the central axis defined by the tube when the tube is arranged between the flanges.

[0049] In some embodiments of this disclosure, the means for regulating fluid flow includes a first elongated support member, a second elongated support member, and an actuator. The first elongated support member defines a length, and the second elongated support member also defines its own length, such that the length of the second elongated support member is arranged in a spaced relation to the length of the first elongated support member to engage with the first elongated support member to compress the tube. The actuator mechanically engages with at least one of the first and second elongated support members to actuate the first and second elongated support members toward each other, thereby compressing the tube disposed between the first and second elongated support members to regulate the flow of fluid within the tube, such that actuation of the actuator actuates the first and second elongated support members to regulate the fluid flow within the tube according to an approximately S-shaped curve.

[0050] The length of the second elongated support member can be arranged approximately parallel to the length of the first elongated support member. The first and second elongated support members can be configured to cooperate with each other to compress the tube along a length at least substantially larger than the diameter of the tube. The actuator can be configured to actuate the first and second elongated support members to compress the tube to regulate the fluid flow within the tube along a predetermined portion of an S-curve.

[0051] In some embodiments of this disclosure, the means for regulating fluid flow includes first and second elongated support members. The first elongated support member defines a length, and a second elongated support member defines a length. The length of the second elongated support member is arranged to be spaced apart from the length of the first elongated support member to engage with the first elongated support member to compress a tube. An actuator mechanically engages with at least one of the first and second elongated support members to actuate the first and second elongated support members toward each other, thereby compressing a tube disposed between the first and second elongated support members to regulate the flow of fluid within the tube, such that actuation of the actuator actuates the first and second elongated support members to regulate the fluid flow within the tube according to an approximate Gompertz curve.

[0052] The length of the second elongated support member can be arranged approximately parallel to the length of the first elongated support member. The first and second elongated support members can be configured to cooperate with each other to compress the tube along a length at least substantially larger than the diameter of the tube.

[0053] The actuator can be configured to actuate first and second elongated support members to compress the tube to regulate the fluid flow within the tube according to a predetermined portion of the Gompertz curve.

[0054] In some embodiments of this disclosure, the means for regulating fluid flow includes first and second elongated support members. The first elongated support member defines a length, and a second elongated support member defines a length such that the length of the second elongated support member is arranged spaced apart from the length of the first elongated support member to engage with the first elongated support member to compress a tube. An actuator is mechanically engaged with at least one of the first and second elongated support members to actuate the first and second elongated support members toward each other, thereby compressing a tube disposed between the first and second elongated support members to regulate the flow of fluid within the tube, such that actuation of the actuator actuates the first and second elongated support members to regulate the fluid flow within the tube according to an approximate generalized logistic function.

[0055] The length of the second elongated support member can be arranged approximately parallel to the length of the first elongated support member. The first and second elongated support members can be configured to cooperate with each other to compress the tube along a length at least substantially larger than the diameter of the tube. The actuator can be further configured to actuate the first and second elongated support members to compress the tube to regulate the fluid flow within the tube according to a predetermined portion of the generalized logistic function.

[0056] In some embodiments of this disclosure, the device for regulating fluid flow includes first and second support members and an actuator. The first support member forms at least one of an arc, multiple arcs, a curve, multiple curves, an arc shape, multiple arc shapes, an S-shape, a C-shape, a convex shape, multiple convex shapes, a concave shape, and multiple concave shapes. A second support member is arranged spaced apart from the first support member to engage with it to compress the tube along a length at least substantially larger than the diameter of the tube. The actuator mechanically engages at least one of the first and second support members to actuate the first and second support members toward each other, thereby compressing the tube disposed between the first and second support members to regulate the flow of fluid within the tube, such that actuation of the actuator actuates the first and second elongated support members to regulate the fluid flow within the tube according to an approximately nonlinear function.

[0057] The approximate nonlinear function can be an approximate generalized logistic function, an approximate sigmoid curve, and / or an approximate Gompertz curve. The actuator can be configured to actuate to thus regulate the fluid flow within the pipe according to a predetermined portion of the approximate nonlinear function.

[0058] In some embodiments of this disclosure, the first support member forms an arc, has a shape substantially composed of arcs, forms a plurality of arcs, has a shape substantially composed of a plurality of arcs, forms a curve, has a shape substantially composed of curves, forms a plurality of curves, has a shape substantially composed of a plurality of curves, forms an arc, has a shape substantially composed of an arc, forms a plurality of arcs, has a shape substantially composed of a plurality of arcs, forms an S-shape, has a shape substantially composed of an S-shape, forms a C-shape, has a shape substantially composed of a C-shape, forms a convex shape, has a shape substantially composed of a convex shape, forms a plurality of convex shapes, has a shape substantially composed of a plurality of convex shapes, forms a concave shape, has a shape substantially composed of a concave shape, forms a plurality of concave shapes, and / or has a shape substantially composed of a plurality of concave shapes.

[0059] The length of the second support member can be arranged approximately parallel to the length of the first support member. The first and second support members can be configured to cooperate with each other to compress the tube along a length at least substantially larger than the diameter of the tube.

[0060] In some embodiments of this disclosure, the device for regulating fluid flow includes a curved, elongated support member and an opposing support member. The curved, elongated support member is elastically deformable and has a first end and a second end. The opposing support member is configured to define a conduit with the curved, elongated support member, such that the conduit is defined between the curved, elongated support member and the opposing member. Deformation of the curved, elongated support member caused by movement of the first and second ends toward each other reduces the internal volume of the conduit. In some embodiments, the conduit may be configured to receive a tube. In other embodiments, the conduit is fluidly sealed, and the device further includes first and second ports in fluid communication with the conduit, such that each port is adapted to couple to a tube.

[0061] In some embodiments of this disclosure, the system for regulating fluid flow includes a flexible conduit and a reverse Bourdon tube valve. The flexible conduit has a fluid path and is configured to allow fluid to pass through it. The reverse Bourdon tube valve is coupled to the flexible conduit to regulate the fluid flowing through the fluid path of the flexible conduit. An actuator may be coupled to the reverse Bourdon tube valve to actuate the valve to regulate the fluid flowing through the fluid path of the flexible conduit. The reverse Bourdon tube valve operates in the opposite manner to the Bourdon tube; deformation of the fluid path causes a change in fluid flow, rather than the fluid flow causing deformation of the fluid path.

[0062] In some embodiments of this disclosure, a system for regulating fluid flow includes a fluid conduit, a valve, and an actuator. The fluid conduit defines a fluid path configured to allow fluid to pass through it. The valve is operatively coupled to the fluid conduit and includes first and second flexible members. A second flexible member is operatively coupled to the first flexible member. The fluid conduit is arranged between the first and second flexible members, and the first and second flexible members are configured to flex to regulate the flow of fluid through the fluid conduit. The actuator is coupled to at least a first end and a second end of the first flexible member. The actuator may be a lead screw, and an electric motor may be coupled to the lead screw to rotate it.

[0063] In some embodiments of this disclosure, the system may include a knob coupled to a lead screw, such that the knob is configured to rotate the lead screw. The knob may be engaged by a motor-driven actuator.

[0064] In some embodiments of this disclosure, an actuator is coupled to a first end and a second end of a first flexible member, and the actuator is configured to flex the first and second ends toward each other and to flex the first and second ends away from each other at least one of the following: the actuator may flex the first and second ends away from each other, and / or the actuator may flex the first and second flexible members such that the first and second ends approach each other. The first and second flexible members may be generally rectangular. When a stopping force is applied to the actuator, the first member and / or the second member may be tensioned to at least substantially stop the fluid flow.

[0065] The system may include a flow meter coupled to the drip chamber (coupled to the fluid tube), such that the flow meter estimates the fluid flow through the drip chamber and therefore also estimates the fluid flow through the fluid tube. The flow meter may be an image sensor-based flow meter.

[0066] The flow meter can be operatively coupled to a motor to actuate the valve, and the system can include control components to control the motor to actuate the valve to achieve the desired flow rate as estimated by the flow meter.

[0067] In some embodiments of this disclosure, the device for regulating fluid flow includes first and second C-shaped members. The first C-shaped member defines an inner surface and an outer surface, and the second C-shaped member defines an inner surface and an outer surface. At least one of the outer surface of the first C-shaped member and the inner surface of the second C-shaped member is configured as a receiving tube. The inner surface of the second C-shaped member is arranged spaced apart from the outer surface of the first C-shaped member. In some specific embodiments, a large area of ​​the inner surface of the second C-shaped member may be adjacent to the outer surface of the first C-shaped member.

[0068] In some embodiments of this disclosure, the second C-shaped member is flexible, and the first C-shaped member is semi-rigid, rigid, and / or an elastomer.

[0069] Flexible components can be formed from materials selected from the group consisting of plastics, polymers, monomers, polypropylene, thermoplastic polymers, ceramics, polyvinyl chloride, and polyethylene.

[0070] In some embodiments of this disclosure, the means for regulating fluid flow includes first and second flexible sheets. A second flexible sheet is operatively coupled to the first flexible sheet. The first and second flexible sheets are configured to receive a fluid conduit between them, and the first and second flexible sheets are also configured to flex to regulate the flow of fluid through the fluid conduit.

[0071] The device may include an actuator coupled to a first end and a second end of a first flexible sheet. The actuator may be configured to flex the first and second ends toward each other and to flex the first and second ends away from each other at least one of the following:

[0072] The device may include a lead screw and a knob, the lead screw being coupled to a first end and a second end of a first flexible sheet, and the knob being coupled to the lead screw such that rotation of the knob causes rotation of the lead screw. The knob may be configured to engage with a motor-driven actuator, thereby actuating the knob.

[0073] In some embodiments of this disclosure, the means for regulating fluid flow includes first and second curved members. The first curved member defines an inner surface and an outer surface, and the second curved member also defines an inner surface and an outer surface. The inner surface of the second curved member is arranged to be spaced apart from the outer surface of the first curved member.

[0074] At least one of the first and second curved members can be configured to position a fluid conduit between them. The first curved member can be at least one of semi-rigid and rigid. The second curved member can be flexible. The second curved member can include an elastomer. Both the first and second curved members can be flexible.

[0075] The device may include a connecting member operatively coupled to at least one of a first end of a first curved member and a first end of a second curved member, such that the connecting member is also operatively coupled to at least one of a second end of the first curved member and a second end of the second curved member. The connecting member may be flexible, rigid, and / or semi-rigid.

[0076] The device may include an actuator positioned between the connecting member and the second curved member to apply a force between the connecting member and the second curved member when actuated. The actuator may be a lead screw.

[0077] In some embodiments of this disclosure, the device for regulating fluid flow includes first and second curved members. The first curved member defines an inner surface and an outer surface. The first curved member has a first receiving member and a second receiving member at both ends of the first curved member. The second curved member defines an inner surface and an outer surface. The second curved member has a first fastener and a second fastener at both ends of the second curved member. At least one of the first and second fasteners may be a hook. The first receiving member of the first curved member is configured to engage the first fastener of the second curved member, and the second receiving member of the first curved member is configured to engage the second fastener of the second curved member.

[0078] At least one of the receiving components can be configured for coupling to a cylindrical component, such as a cylindrical nut, of the hook.

[0079] At least one of the receiving components can be operatively coupled to an actuator. One or more of the receiving components can be operatively coupled to an electric motor.

[0080] In some embodiments of this disclosure, the device further includes an electric motor coupled to a first receiving member such that: (1) the electric motor rotates a rotor coupled to a shaft having threads on its outer surface; (2) the second receiving member defines a threaded hole configured to receive the shaft; and (3) when the electric motor rotates the rotor to thus rotate the shaft, the threaded hole and the shaft engage together to increase or decrease at least one of the distance between the first and second receiving members.

[0081] In some embodiments of this disclosure, the device for regulating fluid flow includes first and second curved elongated support members. The first curved elongated support member is elastically deformable and has a first end and a second end. The second curved elongated support member is elastically deformable and has a first end and a second end. The second curved elongated support member is configured to position a tube against the first curved elongated support member such that deformation of the first and second curved elongated support members caused by movement of the first and second ends of the first curved elongated support member toward each other reduces the internal volume of the tube.

[0082] A first connector is coupled to a first end of a first curved elongated support member and also coupled to a first end of a second curved elongated support member. A second connector is coupled to a second end of the first curved elongated support member and also coupled to a second end of the second curved elongated support member. The second connector defines a hole. A connecting member has one end coupled to the first connector and another end configured for insertion into the hole of the second connector. The connecting member defines a threaded rod at least along its portion. A knob has ratchet teeth configured to engage with the connector member when moved from the other end of the connecting member toward one end of the connector member. The knob is further configured to engage the threaded rod of the connecting member. The knob may include a plurality of fingers configured to engage the threaded rod of the connecting member. The knob defines an outer periphery and includes a hole defined at the center of the outer periphery of the knob. The hole is configured to receive the threaded rod. Each of the plurality of fingers is arcuate to engage the threaded rod at a corresponding end of each of the plurality of fingers.

[0083] The first curved elongated support member defines a first hole adjacent to a first end of the first curved elongated support member. The hole is configured to retain a fluid conduit.

[0084] The first curved elongated support member may define a first groove adjacent to a first end of the first curved elongated support member, such that the groove is configured to receive a fluid conduit. The groove may include a neck configured to receive the fluid conduit and a circular region configured to retain the fluid conduit.

[0085] In some embodiments of this disclosure, the device for regulating fluid flow includes a base, a plurality of fingers, and a ring. The base defines an orifice configured to receive a fluid conduit. Each of the plurality of fingers has an end coupled to the base. The ring is configured to slide from the base along the plurality of fingers. The ring moves away from the base and abuts against the conduit to compress the fingers as they move. The ring is configured to frictionally lock against the plurality of fingers. Each finger includes an elongated end coupled to the base and a curved end coupled to an opposite end relative to the base.

[0086] In some embodiments of this disclosure, the means for regulating fluid flow includes a conical member, a supplementary member, and an actuator. The conical member has a surface for winding around a tube. The supplementary member is configured to engage the conical member to compress the tube. The actuator is configured to press against the supplementary member to compress the conical member, thereby compressing the tube.

[0087] In some embodiments of this disclosure, the intravenous delivery device includes: a flexible tube for guiding fluid flow therein; a first port at a first end of the flexible tube; a second port at a second end of the flexible tube; a curved elongated support member that is elastically deformable and has a first end and a second end; and an opposing support member configured to position the flexible tube against the curved elongated support member between the first end and the second end, such that deformation of the curved elongated support member caused by movement of the first end and the second end toward each other reduces the internal volume of the tube.

[0088] The intravenous delivery device may further include: an infusion chamber coupled to the flexible tube; another port configured to receive a syringe for injecting fluid into a fluid flow within the flexible tube; and / or a sliding occluder coupled to the flexible tube, configured to engage the flexible tube to occlude the fluid flow therein.

[0089] The first end of the curved elongated support member may define a first hole for receiving the flexible tube, and the second end of the curved elongated support member may define a second hole for receiving the flexible tube.

[0090] In some embodiments of this disclosure, the flow meter includes a coupler, a support member, first and second image sensors, and at least one processor. The coupler is adapted to be coupled to a drip chamber. The support member is operatively coupled to the coupler. The first image sensor has a first field of view and is operatively coupled to the support member. The first image sensor is positioned to observe the drip chamber within the first field of view. A second image sensor has a second field of view and is operatively coupled to the support member. The second image sensor is positioned to observe the drip chamber within the second field of view.

[0091] At least one processor is operatively coupled to the first and second image sensors. The at least one processor receives first image data from the first image sensor and second image data from the second image sensor, and the at least one processor uses the first and second image data to estimate at least one parameter of the liquid within the drip chamber.

[0092] The at least one parameter can be one of the liquid formation type, liquid volume, and liquid shape. At least one processor can use at least one of the image data from the first and second sets to determine the presence of free-flow conditions.

[0093] The flow meter may further include a background pattern positioned within the field of view of the first image sensor, such that the drip cavity is positioned between the first image sensor and the background pattern.

[0094] By analyzing the deformation of the background pattern caused by the liquid within a first field of view, as observed by a first image sensor, at least one processor of the flow meter can estimate at least one parameter using a first set of image data. The background pattern may be a linear array that, when observed from the first image sensor within the first field of view using the first set of image data, has at least one angle relative to the opening of the drip chamber.

[0095] When, under free-flow conditions as observed from a first image sensor within a first field of view, at least one processor can determine that free-flow conditions exist when the linear array changes angle due to liquid-induced deformation caused by the liquid.

[0096] At least one processor can compare at least one of the first and second image data with a background image to estimate at least one parameter.

[0097] At least one processor can compare at least one of the first and second image data with a background image by calculating the difference between at least one of the first and second image data and the background image, the absolute difference between at least one of the first and second image data and the background image, and / or the squared absolute difference between at least one of the first and second image data and the background image.

[0098] The flow meter may include a non-transitory processor-readable memory operatively communicatively with at least one processor, such that the memory stores a set of operative processor-executable instructions configured for execution by the at least one processor. The set of operative processor-executable instructions controls the operation of the at least one processor when executed by it.

[0099] In some embodiments of this disclosure, the flow meter includes a coupler, a support member, a background pattern, and at least one processor. The coupler is adapted to be coupled to a drip cavity. The support member is operatively coupled to the coupler. An image sensor has a field of view and is operatively coupled to the support member. The image sensor is positioned to observe the drip cavity within its field of view. The background pattern is positioned within the field of view of the image sensor. The background pattern is positioned such that the drip cavity is between the background pattern and the image sensor. At least one processor is operatively coupled to the image sensor to receive image data therefrom. At least one processor is configured to estimate at least one parameter of the liquid within the drip cavity using deformation of the background pattern caused by the liquid, as indicated by the image data. The deformation is visible to the image sensor within its field of view. The at least one parameter is at least one of the liquid formation type, liquid volume, and liquid shape. The background pattern may be a linear array that, when viewed from the image sensor using the image data, has at least one angle relative to the drip cavity opening.

[0100] At least one processor can determine the presence of free-flow conditions using deformation of a background pattern caused by a liquid, such as as indicated by image data. When observed under free-flow conditions, such as within the field of view of an image sensor, at least one processor can determine the presence of free-flow conditions when the liquid causes the linear array to change angle due to liquid-induced deformation.

[0101] The flow meter may further include a non-transitory processor-readable memory operably in communication with at least one processor. The non-transitory processor-readable memory may store a set of operable processor-executable instructions configured to be executed by at least one processor, such that the set of operable processor-executable instructions, when executed by at least one processor, controls the operation of at least one processor.

[0102] In some embodiments of this disclosure, the flow meter includes a coupler, a support member, an image sensor, and at least one processor. The coupler is adapted to be coupled to a drip chamber. The support member is operatively coupled to the coupler. The image sensor has a field of view and is operatively coupled to the support member such that the image sensor is positioned to observe the drip chamber within the field of view. At least one processor is operatively coupled to the image sensor to receive image data therefrom, such that the at least one processor compares an image of the image data with a reference image to estimate at least one parameter of the liquid within the drip chamber. The reference image may be a dynamic reference image. The at least one processor can update the reference image by multiplying each pixel of the reference image by a first constant and adding the corresponding pixel of the image multiplied by a second constant.

[0103] The flow meter may include a non-transitory processor-readable memory operatively communicative to at least one processor. The non-transitory processor-readable memory may include a set of operative processor-executable instructions configured to be executed by at least one processor, such that the set of operative processor-executable instructions, when executed by at least one processor, controls the operation of at least one processor.

[0104] In some embodiments of this disclosure, a method for exposing an image sensor implemented by a set of operable processor-executable instructions configured to be executed by at least one processor includes: selecting a region of interest; determining whether a pixel is within the region of interest; if the pixel is within the region of interest, activating lamps of a backlight; and exposing the pixel. The activation action may activate a subgroup of lamps, including the lamps of the backlight. The lamps of the backlight may form a uniform backlight. The image sensor may include a region of interest and pixels.

[0105] An operable processor-executable instruction set can be stored on a non-transitory processor-readable memory that is operatively in communication with at least one processor, enabling at least one processor to execute the method.

[0106] At least one processor can be coupled to an image sensor, such that the processor uses the image sensor to perform the method. The region of interest can be the area of ​​the image sensor that images the infusion cavity. The region of interest can correspond to the infusion cavity.

[0107] The method may further include: receiving a vertical synchronization signal from an image sensor; and receiving a horizontal synchronization signal from an image sensor. At least one processor may receive the vertical and horizontal synchronization signals from the image sensor. At least one processor may activate a lamp of the backlight based on at least one of the vertical and horizontal synchronization signals. The lamp may be a light-emitting diode (LED).

[0108] In some embodiments of this disclosure, the flow meter includes a coupler, a support member, an image sensor, a backlight, and at least one processor. The coupler is adapted to be coupled to a drip cavity. The support member is operatively coupled to the coupler. The image sensor has a field of view and is operatively coupled to the support member such that the image sensor is positioned to observe the drip cavity within the field of view. The backlight has at least one lamp. The backlight is coupled to the support member such that the backlight is adapted to illuminate the image sensor to expose the image sensor, wherein the field of view of the image sensor at least partially images at least a portion of the drip cavity. At least one processor is operatively coupled to the image sensor to receive image data therefrom.

[0109] The at least one processor is configured to: select a region of interest of an image sensor; determine whether a pixel of the image sensor is within the region of interest; if a pixel of the image sensor is within the region of interest, activate the lamp of the backlight; and expose the pixel of the image sensor.

[0110] The flow meter may further include a non-transitory processor-readable memory readable by at least one processor. The non-transitory processor-readable memory includes a set of processor-executable instructions stored thereon, the set of processor-executable instructions being configured, when executed, to cause at least one processor to: select a region of interest of an image sensor; determine whether a pixel of the image sensor is within the region of interest; if the pixel of the image sensor is within the region of interest, activate a backlight lamp; and expose the pixel of the image sensor. The at least one processor may be further configured to: receive a vertical synchronization signal from the image sensor; and receive a horizontal synchronization signal from the image sensor. The at least one processor may activate the backlight lamp based on at least one of the vertical synchronization signal and the horizontal synchronization signal.

[0111] At least one processor can select a region of interest and determine, based on image data, whether a pixel of the image sensor is within the region of interest. The region of interest is the area of ​​the image sensor that enables imaging of the drip cavity. The region of interest may correspond to the drip cavity.

[0112] At least one processor can activate a subgroup of lamps, which includes backlight lamps. The backlight lamps can form a uniform backlight.

[0113] In some embodiments of this disclosure, a method includes: capturing an image including an image of the infusion cavity using an image sensor having a field of view including the infusion cavity; subtracting the image from a background image to generate a difference image; converting each pixel of the difference image to a true value if the absolute value of a corresponding pixel exceeds a predetermined threshold, or converting each pixel of the difference image to a false value if the absolute value of a corresponding pixel is less than the predetermined threshold; summing the difference image for each row of the converted difference image to generate a plurality of sums, wherein each of the plurality of sums corresponds to the difference image for the corresponding row; and checking the plurality of sums. The method can be implemented by a set of operable processor-executable instructions stored in a non-transitory processor-readable memory operably in communication with at least one processor, causing at least one processor to perform the method.

[0114] The action of checking multiple sums can include determining whether free-flow conditions exist within the drip chamber.

[0115] The action of determining whether a free-flow condition exists may include determining whether multiple sums are included among multiple consecutive sums above another predetermined threshold.

[0116] The action of checking multiple sums can include determining whether a droplet has formed within the drip chamber.

[0117] The action of determining whether a droplet has formed in the drip chamber may include determining whether multiple sums are included in a predetermined range of consecutive sums that are greater than a minimum value and less than a maximum value.

[0118] The method may optionally include smoothing multiple sums before the inspection action. The smoothing action may be based on at least one of a sample function, a cubic sample function, a B sample function, a Bezier sample function, a polynomial interpolation, a moving average, a data smoothing function, and a cubic sample type function.

[0119] At least one processor may be optionally coupled to an image sensor, and the at least one processor uses the image sensor to perform the method.

[0120] The method may optionally include an action that converts each pixel of the difference image into the absolute value of each pixel after the subtraction action and before the transformation action.

[0121] The method may optionally include an action that converts each pixel of the difference image into the square value of each pixel after the subtraction action and before the transformation action.

[0122] In some embodiments of this disclosure, the flow meter includes a coupler, a support member, a lamp, and at least one processor. The coupler is adapted to be coupled to a drip cavity. The support member is operatively coupled to the coupler. An image sensor has a field of view and is operatively coupled to the support member such that the image sensor is positioned to observe the drip cavity within the field of view. The lamp is coupled to the support member and adapted to illuminate the image sensor to expose the image sensor such that the field of view of the image sensor at least partially images at least a portion of the drip cavity.

[0123] At least one processor is operationally coupled to an image sensor to receive image data therefrom, and the at least one processor is configured to: capture an image including an image of the drip cavity using an image sensor having a field of view including the drip cavity; subtract the image from a background image to generate a difference image; convert each pixel of the difference image to a true value if the absolute value of the corresponding pixel exceeds a predetermined threshold, or convert each pixel of the difference image to a false value if the absolute value of the corresponding pixel is less than the predetermined threshold; sum the difference images for each row of the conversion to generate a plurality of sums, wherein each of the plurality of sums corresponds to the difference image for the corresponding row of the conversion; and check the plurality of sums.

[0124] The flow meter may include: a non-transitory processor-readable memory readable by at least one processor, such that the non-transitory processor-readable memory includes a set of operable processor-executable instructions stored thereon, the set of operable processor-executable instructions being configured, when executed, to cause the at least one processor to: capture an image including an image of the drip cavity using an image sensor having a field of view including the drip cavity; subtract the image from a background image to generate a difference image; convert each pixel of the difference image to a true value if the absolute value of the corresponding pixel is greater than a predetermined threshold, or convert each pixel of the difference image to a false value if the absolute value of the corresponding pixel is less than a predetermined threshold; sum each row of the converted difference image to generate a plurality of sums, wherein each of the plurality of sums corresponds to the converted difference image of the corresponding row; and check the plurality of sums.

[0125] At least one processor is further configured to determine whether a free-flow condition exists within the drip chamber when the processor examines multiple sums.

[0126] At least one processor is further configured to: when the at least one processor determines whether a plurality of sums are included in a plurality of consecutive sums above another predetermined threshold, the sums are determined to be present in a free-flow condition.

[0127] At least one processor is further configured to determine whether a droplet has formed within the drip chamber when the at least one processor examines multiple sum values.

[0128] At least one processor is further configured to determine that a droplet has been formed if the sums include multiple consecutive sums within a predetermined range greater than a minimum value and less than a maximum value, and the positions of these consecutive sums correspond to the positions within a predetermined range where the droplet can form.

[0129] At least one processor is further configured to smooth the sum values ​​before the processor checks them.

[0130] At least one processor can perform smoothing based on at least one of the following: a sampling function, a cubic sampling function, a B sampling function, a Bezier sampling function, a polynomial interpolation, a moving average, a data smoothing function, and / or a cubic sampling type function.

[0131] The flow meter may further include a non-transitory processor-readable memory having a set of operable processor-executable instructions stored thereon. The non-transitory processor-readable memory is operablely in communication with at least one processor, such that the set of operable processor-executable instructions controls the operation of the at least one processor.

[0132] At least one processor is further configured to convert each pixel of the difference image into the absolute value of each pixel after the subtraction action and before the transformation.

[0133] At least one processor is further configured to convert each pixel of the difference image into a squared value of each pixel after the subtraction action and before the transformation.

[0134] In some embodiments of this disclosure, a method includes: capturing an image of a drip cavity using an image sensor; identifying a plurality of pixels of interest within the image; determining a subgroup of pixels within the plurality of pixels of interest, wherein each pixel of the plurality of pixels is determined to be within the subgroup of pixels when a path to a baseline corresponding to the drip cavity exists; performing a rotation operation on the subgroup of pixels; and estimating the volume of a droplet within the drip cavity by counting the number of pixels within the rotated subgroup of pixels.

[0135] The baseline can be a predetermined group of pixels within the image sensor. Multiple pixels of interest can be identified by comparing the image with a background image.

[0136] The method may optionally include one or more of the following: initializing a background image; updating the background image using an image captured by an image sensor; updating the variance array using an image captured by an image sensor; and / or updating the integer array based on an image captured by an image sensor.

[0137] The background image can be updated according to the following equation: P background,i,j =P background,i,j(1-α background )+α background P input,i,j .

[0138] The variance array can be updated according to the following equation:

[0139] Each integer in the integer array may correspond to the number of times the pixels of the background image have been updated. In some specific embodiments, if a corresponding integer in the integer array indicates that a corresponding pixel in the background image has been updated at least a predetermined number of times, then comparing the image with the background image only involves comparing the pixels in the image with the pixels in the background image.

[0140] The method may optionally include one or more of the following: identifying droplets in the image and a predetermined band near the edge of the droplets; and initializing the background image by setting each pixel of the background image as an image, unless it is within the identified droplets or the predetermined band near the edge of the droplets.

[0141] The method further includes: if a corresponding pixel of the image is within the identified droplet or a predetermined band near the edge of the droplet, then setting a pixel of the background image to a predetermined value. The corresponding pixel of the image has a position corresponding to a pixel of the background image.

[0142] The method may further include determining a baseline corresponding to the opening of the drip chamber.

[0143] The action of determining a subgroup of pixels within a plurality of pixels of interest corresponding to a droplet may include: determining each of the plurality of pixels of interest to be within a subgroup of pixels if the corresponding pixel in the plurality of pixels has a continuous path back to the baseline of the droplet formed at the opening of the droplet cavity.

[0144] The method may optionally include one or more of the following: capturing a first image using the image sensor; identifying a droplet within the first image and a predetermined band near the edge of the droplet; initializing the background image by setting each pixel to the first image, unless it is within the identified droplet or the predetermined band near the edge of the droplet; setting pixels within the droplet region or the predetermined band to predetermined values; initializing an integer array; and initializing a variance array.

[0145] The method may also include using an image to update one or more of a background image, an integer array, and / or a variance array.

[0146] In some embodiments of this disclosure, the flow meter includes a coupler, a support member, an image sensor, and at least one processor. The coupler is adapted to be coupled to a drip chamber. The support member is operatively coupled to the coupler. The image sensor has a field of view and is operatively coupled to the support member. The image sensor is positioned to observe the drip chamber within the field of view.

[0147] At least one processor is operatively coupled to an image sensor to receive image data therefrom, and the at least one processor is configured to: use the image sensor to capture an image of the infusion cavity; identify a plurality of pixels of interest within the image; determine a subgroup of pixels within the plurality of pixels of interest, wherein each pixel of the plurality of pixels is determined to be within the subgroup of pixels when a path to a baseline corresponding to the infusion cavity exists; perform a rotation operation on the subgroup of pixels; and estimate the volume of a droplet within the infusion cavity by counting the number of pixels within the rotated subgroup of pixels.

[0148] The flow meter may also include a non-transitory processor-readable memory having a set of operable processor-executable instructions stored thereon. The non-transitory processor-readable memory is operablely in communication with at least one processor, such that the set of operable processor-executable instructions controls the operation of the at least one processor.

[0149] The flow meter may further include: a non-transitory processor-readable memory readable by at least one processor, such that the non-transitory processor-readable memory includes a set of operable processor-executable instructions stored thereon, the set of operable processor-executable instructions being configured, when executed, to cause the at least one processor to: capture an image of the drip chamber using the image sensor; identify a plurality of pixels of interest within the image; determine a subgroup of pixels within the plurality of pixels of interest, wherein each of the plurality of pixels is determined to be within the subgroup of pixels when a path to a baseline corresponding to the drip chamber exists; perform a rotation operation on the subgroup of pixels; and estimate the volume of a droplet within the drip chamber by counting the number of pixels within the rotating subgroup of pixels.

[0150] The baseline can be a predetermined group of pixels within the image sensor. Multiple pixels of interest can be identified by comparing the image with a background image. At least one processor can be further configured to initialize the background image and / or to update the background image using the image captured by the image sensor.

[0151] The background image can be updated according to the following equation: P background,i,j =P background,i,j (1-α background )+α background P input,i,j .

[0152] At least one processor is further configured to update the variance array using images captured by the image sensor.

[0153] The variance array can be updated according to the following equation:

[0154] At least one processor is further configured to update an integer array based on images captured by an image sensor. Each integer in the integer array corresponds to the number of updates to pixels in the background image.

[0155] Optionally, in some embodiments, if the corresponding integer in the integer array indicates that the corresponding pixel in the background image has been updated at least a predetermined number of times, then comparing the image with the background image only involves comparing the pixels in the image with the pixels in the background image.

[0156] The at least one processor may be further configured to: identify droplets in the image and a predetermined band near the edge of the droplets; and initialize the background image by setting each pixel of the background image as an image, unless it is within the identified droplets or the predetermined band near the edge of the droplets.

[0157] At least one processor may be further configured to set the pixels of the background image to a predetermined value if the corresponding pixel of the image is within the identified droplet or a predetermined band near the edge of the droplet.

[0158] In some embodiments of this disclosure, the corresponding pixels of the image have a position corresponding to the position of pixels in the background image.

[0159] At least one processor may be further configured to determine a baseline corresponding to the opening of the drip chamber.

[0160] At least one processor may be further configured to: determine whether each of the plurality of pixels of interest is within a pixel subgroup if the respective pixels of the plurality of pixels have a continuous path returning to the baseline of the droplet formed at the opening of the droplet cavity, so as to determine whether the pixel subgroup is within the plurality of pixels of interest corresponding to the droplet.

[0161] The at least one processor may be further configured to: capture a first image using the image sensor; identify droplets within the first image and a predetermined band near the edge of the droplets; initialize the background image by setting each pixel to the first image, unless it is within the identified droplets or the predetermined band near the edge of the droplets; set pixels within the droplets or the predetermined band to predetermined values; initialize an integer array; and initialize a variance array.

[0162] At least one processor may be further configured to use the image to update the background image, the integer array, and / or the variance array.

[0163] In some embodiments of this disclosure, the flow meter includes an image sensor device and a flow estimator device. The image sensor device is used to capture multiple images of the drip chamber. The flow estimator device is used to estimate the flow of fluid through the drip chamber using the multiple images.

[0164] The flow estimator device may include a processor device for estimating the flow of fluid through the drip chamber using multiple images.

[0165] The flow meter may further include a memory device operatively communicative to a processor device to provide an operable set of processor-executable instructions to cause the processor device to use multiple images to estimate the flow of fluid through the drip chamber.

[0166] In some embodiments of this disclosure, the flow meter includes: a memory device having a set of operable processor-executable instructions configured to be executed; and a processor device for executing the set of operable processor-executable instructions to implement a flow estimator device for estimating the flow of fluid through the drip chamber using the plurality of images.

[0167] In some embodiments of this disclosure, a method includes: the step of capturing a plurality of images of a drip chamber; and the step of using the plurality of images to estimate the flow of fluid through the drip chamber. The method may be implemented by a set of operable processor-executable instructions stored in non-transitory memory and executed by at least one processor.

[0168] In some embodiments of this disclosure, an apparatus includes: a coupler adapted to be coupled to a drip chamber; a support member operatively coupled to the coupler; an image sensor having a field of view and operatively coupled to the support member, wherein the image sensor is positioned to observe the drip chamber within the field of view; a valve configured to be coupled to a fluid conduit in fluid communication with the drip chamber, wherein the valve is configured to regulate flow through the fluid conduit to regulate fluid flow through the drip chamber; and at least one processor operatively coupled to the image sensor to receive image data therefrom, wherein the at least one processor is configured to: use the image sensor to capture a plurality of images of the drip chamber; use the plurality of images to estimate a volume growth rate of droplets within the drip chamber; receive a setpoint corresponding to the fluid flow rate through the fluid conduit; adjust a control system based on the estimated volume growth rate of droplets to achieve the setpoint; and output a control signal from the control system to an actuator of the valve to control actuation of the valve according to the adjusted control system.

[0169] The apparatus may include a non-transitory processor-readable memory having a set of processor-executable instructions operable thereon. The non-transitory processor-readable memory can operably communicate with at least one processor, such that the set of processor-executable instructions operable controls the operation of the at least one processor.

[0170] The apparatus may include a non-transitory processor-readable memory readable by at least one processor. The non-transitory processor-readable memory may include a set of processor-executable instructions stored thereon, the set of processor-executable instructions being configured, when executed, to cause at least one processor to: use the image sensor to capture multiple images of the drip chamber; use the multiple images to estimate a droplet volume growth rate within the drip chamber; receive a setpoint corresponding to the fluid flow rate through the fluid conduit; adjust the control system according to the estimated droplet volume growth rate to achieve the setpoint; and output a control signal from the control system to an actuator of the valve to control the actuation of the valve according to the adjusted control system.

[0171] The control system can be at least one of the following: proportional-integral-derivative control system, proportional-integral control system, proportional-derivative control system, proportional control system, integral control system, neural network control system, fuzzy logic control system, and / or switch control system.

[0172] The control system correlates the estimated volume growth rate of the droplets with the fluid flow through the fluid tube.

[0173] The valve may include: a curved, elongated support member, which is elastically deformable and has a first end and a second end; and an opposing support member configured to position a fluid conduit against the curved, elongated support member between the first end and the second end, wherein deformation of the curved, elongated support member caused by movement of the first end and the second end toward each other reduces the internal volume of the fluid conduit. An actuator may be configured to move the first end and the second end toward each other.

[0174] The valve may include: a first elongated support member of a defined length; and a second elongated support member of a defined length, wherein the length of the second elongated support member is arranged at a distance from the length of the first elongated support member to cooperate with the first elongated support member to compress the fluid conduit. An actuator may mechanically engage at least one of the first and second elongated support members to actuate the first and second elongated support members toward each other, thereby compressing the fluid conduit disposed between the first and second elongated support members to regulate the flow of fluid within the fluid conduit. Actuation of the actuator actuates the first and second elongated support members to regulate the fluid flow within the conduit according to an approximately S-shaped curve.

[0175] The valve may include: a first elongated support member of a defined length; and a second elongated support member of a defined length, wherein the length of the second elongated support member is arranged at a distance from the length of the first elongated support member to engage with the first elongated support member to compress the fluid conduit. An actuator mechanically engages with at least one of the first and second elongated support members to actuate the first and second elongated support members toward each other, thereby compressing the fluid conduit disposed between the first and second elongated support members to regulate the flow of fluid within the fluid conduit. Actuation of the actuator actuates the first and second elongated support members to regulate the fluid flow within the fluid conduit according to an approximate Gompertz curve.

[0176] The valve may include: a first elongated support member of a defined length; and a second elongated support member of a defined length, wherein the length of the second elongated support member is arranged at a distance from the length of the first elongated support member to cooperate with the first elongated support member to compress the fluid conduit. An actuator mechanically engages with at least one of the first and second elongated support members to actuate the first and second elongated support members toward each other, thereby compressing the fluid conduit disposed between the first and second elongated support members to regulate the flow of fluid within the fluid conduit; actuation of the actuator actuates the first and second elongated support members to regulate the fluid flow within the conduit according to an approximate generalized logistic function.

[0177] The valve may include: a first support member forming at least one of an arc, multiple arcs, a curve, multiple curves, an arc shape, multiple arc shapes, an S-shape, a C-shape, a convex shape, multiple convex shapes, a concave shape, and multiple concave shapes; and a second support member arranged spaced apart from the first support member to engage with the first support member to compress the fluid tube along a length at least substantially larger than the diameter of the fluid tube. An actuator mechanically engages at least one of the first and second support members to actuate the first and second support members toward each other, thereby compressing the fluid tube disposed between the first and second support members to regulate the flow of fluid within the fluid tube; actuation of the actuator actuates the first and second elongated support members to regulate the fluid flow within the fluid tube according to an approximately nonlinear function.

[0178] The valve may include: a curved, elongated support member that is elastically deformable and has a first end and a second end; and an opposing support member configured to define a conduit with the curved, elongated support member. The conduit is defined between the curved, elongated support member and the opposing member. A fluid conduit is disposed within the conduit, and the deformation of the curved, elongated support member caused by movement of the first and second ends toward each other reduces the internal volume of the fluid conduit.

[0179] The valve can be a reverse Bourdon valve, which is coupled to a fluid line to regulate the fluid flowing through the fluid line.

[0180] The valve may include: a first flexible member; and a second flexible member operatively coupled to the first flexible member. A fluid conduit may be arranged between the first and second flexible members. The first and second flexible members are configured to flex to thus regulate the flow of fluid through the fluid conduit, and an actuator is coupled at least to a first end of the first flexible member and a second end of the first flexible member.

[0181] The valve may include: a first C-shaped member defining an inner surface and an outer surface; and a second C-shaped member defining an inner surface and an outer surface. At least one of the outer surface of the first C-shaped member and the inner surface of the second C-shaped member is configured to receive the fluid conduit. The inner surface of the second C-shaped member is arranged to be spaced apart from the outer surface of the first C-shaped member. An actuator is coupled to the first and second C-shaped members to bend the first and second C-shaped members to compress the fluid conduit.

[0182] The valve may include: a first flexible plate; and a second flexible plate operatively coupled to the first flexible plate. The first and second flexible plates are configured to receive a fluid conduit between them. The first and second flexible plates are configured to flex to thus regulate the flow of fluid through the fluid conduit. An actuator is coupled to the first and second flexible plates to regulate the flow of fluid through the fluid conduit.

[0183] The valve may include: a first curved member defining an inner surface and an outer surface; and a second curved member defining an inner surface and an outer surface. The inner surface of the second curved member is arranged to be spaced apart from the outer surface of the first curved member, and a fluid conduit is arranged between the first and second curved members. An actuator is coupled to the first and second curved members to bend the first and second curved members to thereby regulate the flow of fluid within the fluid conduit.

[0184] The valve may include: a first curved member defining an inner surface and an outer surface, the first curved member having first and second receiving members at its two ends; and a second curved member defining an inner surface and an outer surface, the second curved member having first and second fasteners at its two ends. The first receiving member of the first curved member is configured to engage the first fastener of the second curved member. The second receiving member of the first curved member is configured to engage the second fastener of the second curved member. An actuator is coupled to the first and second curved members to bend the first and second curved members to regulate the flow of fluid within a fluid conduit disposed therebetween.

[0185] The valve may include: a first curved elongated support member, the first curved elongated support member being elastically deformable and having a first end and a second end; a second curved elongated support member, the second curved elongated support member being elastically deformable and having a first end and a second end, wherein the second curved elongated support member is configured to position a fluid tube against the first curved elongated support member, wherein deformation of the first and second curved elongated support members caused by movement of the first and second ends of the first curved elongated support member toward each other reduces the internal volume of the fluid tube; a first connector, the first connector being coupled to the first end of the first curved elongated support member and coupled to... The system includes: a first end of a second curved elongated support member; a second connector coupled to a second end of both the first and second curved elongated support members, wherein the second connector defines an aperture; a connecting member having one end coupled to the first connector and another end configured for insertion into the aperture of the second connector, wherein the connecting member defines a threaded rod at least along a portion thereof; and a ratchet knob configured to engage with the connector member when moved from the other end of the connecting member toward one end of the connector member, wherein the knob is further configured to engage the threaded rod of the connecting member. An actuator may be coupled to the knob to rotate the knob.

[0186] The valve may include: a base defining an orifice configured to receive a fluid conduit; a plurality of fingers, each having an end coupled to the base; and a ring configured to slide from the base along the plurality of fingers. The ring moves from the base against the fluid conduit, compressing the fingers. The ring is configured to frictionally lock against the plurality of fingers. An actuator is coupled to the ring to cause the ring to slide.

[0187] The valve may include: a conical member having a surface for winding around a fluid tube; and a supplementary member configured to engage the conical member to compress the tube. An actuator is configured to press the conical member against the supplementary member to compress the fluid tube.

[0188] The control system can be implemented in hardware, software, a combination of hardware and software, and / or by at least one operational amplifier.

[0189] The device may include a non-transitory processor-readable memory, wherein: the control system is implemented by an operable processor-executable instruction set configured for execution by at least one processor, the operable processor-executable instruction set being stored on the non-transitory processor-readable memory, and the non-transitory processor-readable memory being operablely in communication with at least one processor to transmit operations of the operable processor-executable instruction set to at least one processor for execution by the at least one processor.

[0190] The setpoint can be compared to the droplet's volume growth rate to adjust the control system. The setpoint can also be compared to the droplet's volume growth rate to determine an error signal. The error signal can be the difference between the setpoint and the droplet's volume growth rate. The error signal can be transmitted through a signal processing device to generate an output signal. The signal processing device can utilize at least one non-zero gain parameter to implement a proportional-integral-derivative (PID) controller.

[0191] In another embodiment of this disclosure, the device for regulating fluid flow includes a curved, elongated support member and opposing support members. The curved, elongated support member is elastically deformable and has a first end and a second end. The first end is configured to be pivotally coupled to first and second dogbone links, and the second end is configured to be pivotally coupled to third and fourth dogbone links. The opposing support members are configured to position a tube against the curved, elongated support member between the first and second ends, such that deformation of the curved, elongated support member caused by movement of the first and second ends toward each other reduces the inner cross-section of the tube along its length. The first end of the opposing support member is configured to be pivotally coupled to the first and second dogbone links, and the second end of the opposing support member is configured to be pivotally coupled to the third and fourth dogbone links.

[0192] The first end of the curved, elongated support member may include an engaging finger configured to engage the rack. The second end of the curved, elongated member may be configured to be pivotally coupled to the rack. The device may include a knob coupled to the first end of the curved, elongated support member to move the rack.

[0193] In another embodiment of this disclosure, the flow meter includes a coupler, a support member, an image sensor, a laser, and at least one processor. The coupler is adapted to be coupled to a drip cavity. The support member is operatively coupled to the coupler. The image sensor has a field of view and is operatively coupled to the support member, and a first image sensor is configured to observe the drip cavity within the field of view. The laser is configured to illuminate a binary optical assembly with optical light.

[0194] At least one processor is operatively coupled to an image sensor such that: (1) at least one processor receives data from the image sensor, in which at least a portion of a background pattern is displayed; and (2) at least one processor uses the image data to estimate at least one parameter of the liquid within the drip chamber.

[0195] In another embodiment of this disclosure, the flow meter includes a coupler, a support member, first and second electrodes, and at least one processor. The coupler is adapted to be coupled to a drip chamber. The support member is operatively coupled to the coupler. The first electrode is configured to be coupled to a fluid line in fluid communication with the drip chamber. The second electrode is configured to be coupled to a fluid line in fluid communication with the drip chamber.

[0196] At least one processor is operatively coupled to the first and second electrodes to measure the capacitance between them, and the at least one processor is configured to monitor this capacitance. The at least one processor may be configured to use the monitored capacitance to determine the presence of fluidization conditions within the drip chamber.

[0197] In another embodiment of this disclosure, the safety valve includes a housing, first and second plugging arms, first and second shafts, and a spring. The housing is configured to retain the tube. The first and second plugging arms are pivotally coupled together. A first shaft is pivotally coupled to the distal end of the first plugging arm. A second shaft is pivotally coupled to the distal end of the second plugging arm. The spring is arranged adjacent to the first and second plugging arms on opposite sides of the tube and is configured to spring-load the first and second plugging arms. The safety valve is configured to release the spring and seal the tube when the first and second plugging arms pivot a predetermined amount away from the spring along their common pivot. A solenoid can be used to engage the first and second plugging arms to release the spring.

[0198] In another embodiment of this disclosure, the apparatus includes a coupler, a support member, and at least one processor. The coupler is adapted to be coupled to a drip cavity. The support member is operatively coupled to the coupler. An image sensor has a field of view and is operatively coupled to the support member. The image sensor is configured to observe the drip cavity within the field of view. At least one processor is operatively coupled to the image sensor to receive image data therefrom, and the at least one processor is configured to: (1) capture an image of the drip cavity; (2) position a template within the captured image at a first position; (3) average the pixels within the template to determine a first average value; (4) move the template to a second position; (5) average the pixels within the template to determine a second average value; (6) determine that the template is positioned at the edge of a droplet if the difference between the second average value and the first average value is greater than a predetermined threshold; and (7) correlate the second position with the volume of the droplet.

[0199] In another embodiment of this disclosure, a method implemented by at least one processor executing an operable processor-executable instruction set configured for execution by the at least one processor to estimate flow rate is disclosed. The method includes: (1) capturing an image of a drip chamber; (2) positioning a template within the captured image at a first location; (3) averaging pixels within the template to determine a first average value; (4) moving the template to a second location; (5) averaging pixels within the template to determine a second average value; (6) determining that the template is positioned at a droplet edge if the difference between the second average value and the first average value is greater than a predetermined threshold; and (7) associating the second location with the volume of the droplet.

[0200] In another embodiment of this disclosure, the flow meter includes a coupler, a support member, a modular backlight assembly, an image sensor, and at least one processor. The coupler is adapted to be coupled to a drip chamber. The support member is operatively coupled to the coupler. The modular backlight assembly is configured to provide a first backlight and a second backlight. The image sensor has a field of view and is operatively coupled to the support member. The image sensor is configured to observe the drip chamber and the modular backlight assembly within the field of view. At least one processor is operatively coupled to the image sensor and the modular backlight assembly, such that the at least one processor receives data from the image sensor, which displays at least a portion of the modular backlight assembly therein, and the at least one processor is configured to modulate the backlight assembly to the first backlight and to the second backlight when the droplet size is estimated. The first backlight may be a diffuser backlight without a pattern, and the second backlight may be a diffuser backlight with a striped pattern.

[0201] In another embodiment of this disclosure, the tube restorer includes first and second gears. A second gear is arranged adjacent to the first gear. The first and second gears define a space along radial portions of their respective portions to allow the tube to flex between them. The first and second gears are further configured to restore the tube upon rotation such that the space is not positioned between the first and second gears.

[0202] In another embodiment of this disclosure, the valve includes first and second metal strips and first and second guide members. The first guide member is coupled to the distal ends of the first and second metal strips. The second guide member is coupled to the proximal ends of the first and second metal strips. The first and second metal strips are configured to compress a tube when the distal ends of the first and second metal strips are actuated toward the proximal ends of the first and second metal strips. The valve may further include a cord (e.g., a metal cord or a cord made of any other material) that is threaded through the first and second metal strips and helically wound around the tube.

[0203] In another embodiment of this disclosure, the valve includes first and second clamshells configured to provide a cavity between the first and second clamshells. The first and second clamshells are configured to receive a tube between them and within the cavity. The valve also includes a bladder disposed within the cavity and a pump configured to inflate or de-inflate the bladder to regulate the flow of fluid within the tube.

[0204] In another embodiment of this disclosure, the apparatus includes a coupler, a support member, an image sensor, and at least one processor. The coupler is adapted to be coupled to a drip cavity. The support member is operatively coupled to the coupler. The image sensor has a field of view and is operatively coupled to the support member. The image sensor is configured to observe the drip cavity within the field of view.

[0205] At least one processor is operated coupled to an image sensor to receive image data therefrom and is configured to: (1) capture a first image; (2) create a first thresholded image from the first image by comparing each pixel of the first image with a threshold; (3) determine a group of pixels in the first thresholded image that are connected to a predetermined group of pixels in the first thresholded image; (4) filter all remaining pixels in the first thresholded image that are not in the pixel group, the filtering being performed pixel by pixel in the time domain to generate a first filtered image; (5) remove pixels from the first thresholded image that are determined not to be droplets using the first filtered image to generate a second image; (6) determine a second group of pixels in the second image that are connected to the predetermined group of pixels in the second image to generate a third image, the third image identifying the second group of pixels in the second image; (7) by counting the pixels containing... (7) Determine the first length of the droplet corresponding to the number of rows of pixels in the second pixel group within the third image, the first length corresponding to the first estimated droplet size; (8) Update the background image using the first image; (9) Create a second thresholded image by comparing the first image with the background image; (10) Summate the rows of the second thresholded image to create a sum of multiple rows, each sum corresponding to a row of the second thresholded image; (11) Start at the row position of the second thresholded image having the first of the multiple sums corresponding to the first length; (12) Increment the row position until the row position corresponds to the sum of the corresponding row which is zero; (13) Determine a second length equal to the current row position, the second length corresponding to the second estimated droplet size; and (14) Average the first and second lengths to determine an average length corresponding to the third estimated droplet size.

[0206] In another embodiment of this disclosure, a method implemented by at least one processor executing an operable processor-executable instruction set configured for execution by the at least one processor to estimate flow rate, the method comprising: (1) capturing a first image; (2) creating a first thresholded image from the first image by comparing each pixel of the first image with a threshold; (3) determining a group of pixels within the first thresholded image that are connected to a predetermined group of pixels within the first thresholded image; (4) filtering all remaining pixels of the first thresholded image that are not within the pixel group, the filtering being performed pixel-by-pixel in the time domain to generate a first filtered image; (5) removing pixels determined to be non-droplet portions from the first thresholded image using the first filtered image to generate a second image; and (6) determining a second group of pixels within the second image that are connected to the predetermined group of pixels within the second image to generate a third image, the third... (7) Image recognition of a second pixel group within a second image; (8) determining a first length of the droplet by counting the number of rows containing pixels corresponding to the second pixel group within a third image, the first length corresponding to a first estimated droplet size; (9) updating a background image using the first image; (10) creating a second thresholded image by comparing the first image with the background image; (11) summing the rows of the second thresholded image to create a sum of multiple rows, each sum corresponding to a row of the second thresholded image; (12) starting at a row position of the second thresholded image having the first of the multiple sums corresponding to the first length; (13) incrementing the row position until the row position corresponds to a zero sum of the corresponding row; (14) determining a second length equal to the current row position, the second length corresponding to a second estimated droplet size; and (15) averaging the first and second lengths to determine an average length corresponding to a third estimated droplet size.

[0207] In another embodiment of this disclosure, the flow meter includes a coupler, a support member, first and second loop antennas, and at least one processor. The coupler is adapted to be coupled to a drip chamber. The support member is operatively coupled to the coupler. The first loop antenna is arranged adjacent to a fluid line in fluid communication with the drip chamber. The second loop antenna is arranged adjacent to the fluid line. The at least one processor is operatively coupled to the first and second loop antennas to measure the magnetic coupling between them. The at least one processor is configured to monitor the magnetic coupling between the first and second loop antennas to determine the presence of fluidization conditions within the drip chamber.

[0208] In another embodiment of this disclosure, the method implemented by an operable processor-executable instruction set includes: (1) determining a plurality of points of interest within an image; (2) randomly selecting N points of interest from the plurality of points of interest; and / or (3) identifying a single unique geometric feature characterized by N parameters corresponding to the N points of interest.

[0209] In another embodiment of this disclosure, the system includes a non-transitory memory and one or more processors. The non-transitory memory has a plurality of instructions stored thereon. The one or more processors are operatively communicative with the non-transitory memory to execute the plurality of instructions. The plurality of instructions are configured to cause the processor to: (1) determine a plurality of points of interest within an image; (2) randomly select N points of interest from the plurality of points of interest; and / or (3) identify a single unique geometric feature characterized by N parameters corresponding to the N points of interest. Attached Figure Description

[0210] These and other aspects will become more apparent from the following detailed description of various embodiments of the present disclosure, with reference to the accompanying drawings, in which:

[0211] Figure 1 A block diagram is shown for a system for regulating fluid flow according to embodiments of the present disclosure;

[0212] Figure 2 A flowchart illustrating a method for exposing an image sensor according to an embodiment of the present disclosure is shown;

[0213] Figure 3 Illustrations of embodiments according to this disclosure are shown. Figure 2 Timing diagrams of embodiments of the method;

[0214] Figures 4A-4B Image data (i.e., images) captured by a flow meter in a drip chamber according to an embodiment of the present disclosure are shown to illustrate the use of [the present disclosure]. Figure 3 Using time series diagrams to expose Figure 2 An illustration of an embodiment of the image sensor method;

[0215] Figure 5 A diagram showing a flow meter and valve integrated together for coupling to the drip chamber and IV bag according to an embodiment of the present disclosure;

[0216] Figure 6 This is a block diagram of an imaging system for imaging a flowmeter for imaging a drip chamber according to embodiments of the present disclosure;

[0217] Figure 7 It is based on the embodiments of this disclosure. Figure 6 A diagram illustrating images captured by the system's image sensor;

[0218] Figure 8 This is a block diagram of an imaging system for a flowmeter that uses a background pattern to image a drip cavity, according to an embodiment of the present disclosure.

[0219] Figure 9 This is a schematic illustration of an image captured by the image sensor of the flowmeter disclosed herein when free-flow conditions are present, according to an embodiment of the present disclosure;

[0220] Figure 10 This is a schematic illustration of an image captured by the image sensor of a flow meter and used as a background image according to an embodiment of the present disclosure;

[0221] Figure 11 This is a schematic illustration of an image captured by an image sensor when a droplet is formed in the dripping chamber according to an embodiment of the present disclosure;

[0222] Figure 12 This is a schematic illustration of an image captured by an image sensor and used as a background image according to an embodiment of the present disclosure;

[0223] Figure 13 According to embodiments of this disclosure Figure 11 and Figure 12 A graphical illustration of the differences between images, along with additional processing;

[0224] Figure 14 Use according to embodiments of this disclosure Figure 11-13 A graphical representation of some image processing performed to determine the existence of free-flow conditions;

[0225] Figure 15 This is a schematic diagram of an image captured by an image sensor when free-flow conditions are present, according to an embodiment of the present disclosure;

[0226] Figure 16 This is a schematic illustration of an image captured by an image sensor and used as a background image according to an embodiment of the present disclosure;

[0227] Figure 17 This is an embodiment of the present disclosure for use in detecting free-flow conditions. Figure 15 and Figure 16 A graphical illustration of the differences between the images, along with some additional processing;

[0228] Figure 18 Use according to embodiments of this disclosure Figure 15-17 A graphical representation of some image processing performed to determine the existence of free-flow conditions;

[0229] Figure 19 The illustration shows a pattern matching template used to determine the presence of free-flow conditions according to an embodiment of the present disclosure;

[0230] Figure 20 This is a graphical illustration of the difference between a reference image according to an embodiment of the present disclosure and an image containing the difference between the image and an image that utilizes edge detection and line detection processing for use in detecting free-flow conditions.

[0231] Figure 21This is a schematic diagram of an image of a drip chamber captured by an image sensor when free-flow conditions are present, according to an embodiment of the present disclosure;

[0232] Figure 22 This is a block diagram of an imaging system for use with a flow meter and a light source according to an embodiment of the present disclosure, wherein the flow meter has a striped background pattern and the light source illuminates the stripes from a position adjacent to an image sensor;

[0233] Figure 23 This is a block diagram of an imaging system for use with a flow meter and a light source according to an embodiment of the present disclosure, the flow meter having a striped background pattern, the light source illuminating the stripes from behind the background pattern relative to the opposite end of the image sensor;

[0234] Figure 24 The figure illustrates an embodiment of the present disclosure where a droplet causes... Figure 23 The background pattern is distorted in the image from the image sensor;

[0235] Figure 25 This is a block diagram of an imaging system for use with a flow meter and a light source according to an embodiment of the present disclosure, the flow meter having a background pattern with a checkerboard pattern, the light source illuminating the stripes from behind the background pattern relative to the opposite end of the image sensor.

[0236] Figure 26 This illustrates how, according to an embodiment of the present disclosure, when droplets distort a background pattern, the background pattern is affected by... Figure 25 Images from the image sensor;

[0237] Figure 27-28 A flowchart illustrating a method for estimating the volume of a droplet within a drip chamber according to an embodiment of the present disclosure;

[0238] Figures 29-31 The images shown are those used or generated by a flow meter according to embodiments of the present disclosure, for use by... Figure 27-28 The illustrated method is used to estimate the volume of the droplet within the drip chamber;

[0239] Figure 32 An embodiment of the present disclosure is shown for use according to... Figure 27-28 The method is used to identify pseudocode for multiple pixels of interest;

[0240] Figure 33-36 Additional images are shown, illustrated according to embodiments of the present disclosure, of flow meters used or generated for use by... Figure 27-28 The illustrated method is used to estimate the volume of the droplet within the drip chamber;

[0241] Figure 37 Pseudocode is shown for determining pixel subgroups corresponding to droplets within a plurality of pixels of interest, according to embodiments of the present disclosure;

[0242] Figure 38 A ray diagram showing the diameter of the blurred circle of an image sensor aspect of the imaging system disclosed herein, illustrating an embodiment of the present disclosure.

[0243] Figure 39 This is a diagram illustrating the calculation of various lens-to-focal-plane spacings and lens-to-image spacings of the image sensor of the imaging system disclosed herein, according to embodiments of the present disclosure.

[0244] Figure 40 This is a diagram illustrating blurred circles segmented by pixel size when using a 20mm focal length lens of an image sensor of an imaging system disclosed herein, according to an embodiment of the present disclosure.

[0245] Figure 41 This is a diagram illustrating blurred circles segmented by pixel size when using a 40mm focal length lens of an image sensor of the imaging system disclosed herein, according to an embodiment of the present disclosure.

[0246] Figure 42 A table illustrating the corresponding fields of view near the optical axis of two configurations of the imaging system disclosed herein, according to embodiments of the present disclosure;

[0247] Figure 43 A flow meter coupled to a drip chamber according to an embodiment of the present disclosure is shown;

[0248] Figure 44 The illustration shows the door in an open state according to an embodiment of the present disclosure. Figure 43 Flow meter and drip chamber;

[0249] Figure 45 A flow meter coupled to a drip chamber according to an embodiment of the present disclosure is shown;

[0250] Figure 46 The illustration shows a flow meter according to an embodiment of the present disclosure and a pinch valve coupled to the body of the flow meter to control the flow of fluid into a patient's body;

[0251] Figure 47 The coupling according to an embodiment of the present disclosure is shown. Figure 46 A close-up view of the pinch valve of the main body of the flow meter;

[0252] Figure 48 A flow meter and pinch valve according to another embodiment of the present disclosure are shown, wherein the flow meter includes two image sensors;

[0253] Figure 49 The illustration shows a flow meter according to an embodiment of the present disclosure and a valve including two curved elongated support members to control the flow of fluid into a patient's body;

[0254] Figures 50A-50B Embodiments according to this disclosure are shown Figure 49 A close-up view of the valve;

[0255] Figures 51A-51D Several views of a flow meter having a monitoring client, a valve, a drip chamber, an IV bag, and a fluid tube according to an embodiment of the present disclosure are shown, wherein the flow meter includes a receiving portion for receiving the valve;

[0256] Figures 52A-52D Several views of another flow meter having a valve, a drip chamber, and a tube according to an embodiment of the present disclosure are shown, wherein the flow meter has a receiving portion for receiving the valve;

[0257] Figure 53A Embodiments according to this disclosure are shown Figures 51A-51D and Figures 52A-52D Another view of the valve;

[0258] Figure 53B-53C Embodiments according to this disclosure are shown Figure 53A Two exploded views of the valve;

[0259] Figure 54 Figure 53 illustrates a valve used manually according to an embodiment of this disclosure;

[0260] Figure 55 A valve comprising two flexible members is shown according to an embodiment of the present disclosure;

[0261] Figures 56A-56C Several views of a valve having two curved elongated support members according to an embodiment of the present disclosure are shown, each elongated support member having a plurality of ridges adapted to engage a tube.

[0262] Figures 57A-57C Several views of a valve having ratchet teeth with engaging connection members according to an embodiment of the present disclosure are shown.

[0263] Figure 57D-57E Embodiments according to this disclosure are shown Figures 57A-57C Two exploded views of the valve;

[0264] Figures 58A-58D Several views of a valve having two elongated support members, a connecting member, and a helical actuator according to another embodiment of the present disclosure are shown;

[0265] Figures 59A-59C Several views of the body of a valve according to an embodiment of the present disclosure are shown;

[0266] Figure 59D-59G This illustration shows an embodiment of the invention for use with... Figures 59A-59CSeveral views of the knob used together with the main body shown;

[0267] Figure 59H The embodiments shown include those according to this disclosure. Figures 59A-59C The coupling shown is connected to Figure 59D-59G The main body of the knob is equipped with the valve;

[0268] Figure 60 A valve with a guide protrusion is shown according to an embodiment of the present disclosure;

[0269] Figure 61 An embodiment of the present disclosure is shown for coupling to Figure 60 The valve's motor and valve mounting structure;

[0270] Figure 62 The fastening according to an embodiment of the present disclosure is shown. Figure 61 Motor and valve fixed structure Figure 60 The valve;

[0271] Figure 63 An embodiment of the present disclosure is shown for coupling to Figure 60 The valve has another motor and a valve mounting structure;

[0272] Figure 64A A valve according to an embodiment of the present disclosure is shown having a retaining ring and a plurality of fingers for regulating the flow of fluid through a fluid line;

[0273] Figure 64B Embodiments according to this disclosure are shown Figure 64A A cross-sectional view of the valve;

[0274] Figure 65 A cross-sectional view of a valve having two curved surfaces according to an embodiment of the present disclosure is shown, the two curved surfaces being used to position a fluid tube between them to regulate the flow of fluid through the fluid tube;

[0275] Figure 66A-66G Several views of a valve with a knob according to an embodiment of the present disclosure are shown, which, after being moved, causes a locking connecting member to move.

[0276] Figure 67 A diagram illustrating the flow rate of the actuator relative to the valve according to an embodiment of the present disclosure is shown.

[0277] Figure 68A A flow meter using binary optical elements according to an embodiment of the present disclosure is shown;

[0278] Figure 68B Illustration of an embodiment of the present invention Figure 68A The first and second electrodes in the antenna are used as a loop antenna;

[0279] Figures 69A-69F Several views of a safety valve that can be used with a flow meter according to an embodiment of the present disclosure are shown;

[0280] Figure 70 A flowchart illustrating a method for estimating droplet growth and / or flow within a drip chamber according to embodiments of the present disclosure is shown.

[0281] Figures 71A-71E The image shown is taken by a flow meter according to an embodiment of the present disclosure, the flow meter having features superimposed therein for illustration. Figure 70 A template for the method;

[0282] Figure 72 A modular backlight assembly according to an embodiment of the present disclosure is shown;

[0283] Figures 73A-73C Several views of a tube recovery apparatus according to an embodiment of the present disclosure are shown;

[0284] Figure 74 A system for regulating fluid flow using a valve having two flexible strips, according to an embodiment of the present disclosure, is shown.

[0285] Figure 75 Embodiments according to this disclosure are shown Figure 74 The valve;

[0286] Figure 76A A valve utilizing a fluid-based bladder is shown according to an embodiment of the present disclosure;

[0287] Figure 76B Embodiments according to this disclosure are shown Figure 76A A cross-sectional view of an assembled valve with two elastic packings;

[0288] Figure 77 A system for regulating fluid flow using a valve having two flexible strips actuated by a linear actuator is shown according to an embodiment of the present disclosure;

[0289] Figure 78 The illustration shows an actuated valve according to an embodiment of the present disclosure. Figure 77 The system;

[0290] Figure 79 Embodiments according to this disclosure are shown Figures 77-78 A close-up view of the valve;

[0291] Figure 80 As shown in the embodiments of this disclosure Figure 78 A close-up view of the valve being actuated;

[0292] Figure 81The following illustrations are provided to illustrate the estimation method according to embodiments of the present disclosure. Figures 82A-82B Several images illustrating methods for droplet growth and / or fluid flow; and

[0293] Figures 82A-82B A flowchart illustrating a method for estimating droplet growth and / or fluid flow according to embodiments of the present disclosure is shown; and

[0294] Figure 83 A flowchart illustrating a method for reducing noise from condensation according to an embodiment of the present disclosure is shown. Detailed Implementation

[0295] Figure 1 A block diagram of a system 1 for regulating fluid flow according to embodiments of the present disclosure is shown. For example, system 1 can regulate, monitor, and / or control the flow of fluid into a patient 3. System 1 includes a fluid reservoir 2 for injecting fluid contained therein into the patient 3. The fluid reservoir 2 is supplied by gravity to an infusion chamber 4 via a fluid conduit 5. The fluid reservoir 2, the infusion chamber 4, and the patient 3 can be considered as part of system 1, or as independent or optional components of system 1 (e.g., any fluid reservoir 2 and infusion chamber 4 can be used to treat any patient 3).

[0296] Flow meter 7 monitors drip chamber 4 to estimate the flow rate of liquid flowing through drip chamber 4. Fluid is supplied from drip chamber 4 to valve 6 by gravity. Valve 6 regulates (i.e., alters) the flow of fluid from fluid reservoir 2 to patient 3 by regulating the fluid flow from drip chamber 4 to patient 3. Valve 6 can be any valve as described herein, including valves with two curved members, valves with two flexible flaps, valves that are clamped (or uniformly compressed) over a significant length of the tube, etc. Valve 6 can be an inverted Bourdon tube valve that operates in the opposite manner to a Bourdon tube, where deformation of the fluid path causes a change in fluid flow rather than fluid flow causing deformation of the fluid path.

[0297] In an alternative embodiment, system 1 may optionally include an injection pump 414 (e.g., a peristaltic pump, finger pump, linear peristaltic pump, rotary peristaltic pump, cassette-based pump, diaphragm pump, other pumps, etc.) coupled to fluid line 5. The dashed box designated 414 represents an optional property of injection pump 414; for example, in some embodiments, an injection pump may not be used. Injection pump 414 may use flow meter 7 as feedback to control the flow of fluid through fluid line 5. Injection pump 414 may wirelessly communicate with flow meter 7 to receive flow rate from flow meter 7. Injection pump 414 may use feedback control algorithms (e.g., Figure 1The control unit 14 regulates the flow of fluid, and the feedback control algorithm includes proportional-integral-derivative (“PID”), switching, neural networks, and / or fuzzy logic control systems. In this particular exemplary embodiment (i.e., the embodiment with syringe pump 414), valve 6 is optional. However, in other embodiments, valve 6 may or may not be used, and / or valve 6 is optional. Syringe pump 414 can regulate the rotation of a cam and / or motor based on measurements from flow meter 7, such as flow rate, volume injected, total volume injected, etc. Additionally or alternatively, syringe pump 414 can stop fluid flow (e.g., by stopping pumping action) when flow meter 7 is connected to syringe pump 414 where free-flow conditions exist. In other embodiments, monitoring client 8 controls the operation of syringe pump 414 (e.g., wirelessly) and receives feedback from flow meter 7.

[0298] In some embodiments, the fluid reservoir 2 is pressurized to facilitate the flow of fluid from the fluid reservoir 2 into the patient 3, for example, when the fluid reservoir 2 (e.g., an IV bag) is located below the patient 3. Pressurization provides sufficient mechanical energy to induce fluid flow into the patient 3. Various pressure sources, such as physical pressure, mechanical pressure, and pneumatic pressure, can be applied to the inside or outside of the fluid reservoir 2. In one such embodiment, pressurization can be provided by a rubber band wrapped around the IV bag.

[0299] Flow meter 7 and valve 6 can form a closed-loop system to regulate fluid flow to patient 3. For example, flow meter 7 can receive the target flow rate from monitoring client 8 via communication using transceivers 9 and 10. That is, transceivers 9 and 10 can be used for communication between flow meter 7 and monitoring client 8. Transceivers 9 and 10 can communicate with each other using modulated signals to encode various types of information such as digital data or analog signals. Some modulation techniques used may include using a carrier frequency with FM modulation, using AM modulation, using digital modulation, using analog modulation, etc.

[0300] Flowmeter 7 estimates the flow rate through drip chamber 4 and regulates valve 6 to achieve the target flow rate received from monitoring client 8. Valve 6 can be controlled by flowmeter 7, which is directly coupled to the actuator of valve 6 via a communication line, or wirelessly coupled from flowmeter 7 to the onboard circuitry of valve 6. The onboard electronics of valve 6 can be used to control the actuation of valve 6 via the actuator coupled to valve 6. This closed-loop embodiment of flowmeter 7 and valve 6 can utilize any control algorithm, including PID control algorithms, neural network control algorithms, fuzzy logic control algorithms, and combinations thereof.

[0301] Flow meter 7 is coupled to support member 17, which is coupled to drip chamber 4 via coupler 16. Support member 17 also supports backlight 18. Backlight 18 includes LED array 20, which provides illumination for flow meter 7. In some specific embodiments, backlight 18 includes background pattern 19. In other embodiments, backlight 18 does not include background pattern 19. In some embodiments, background pattern 19 is present only in the lower part of backlight 18 and is not present at the top of backlight 18 (e.g., above the ground).

[0302] The flow meter 7 includes an image sensor 11, a free-flow detector component 12, a flow estimator component 13, a control component 14, an exposure component 29, a processor 15, and a transceiver 9. The flow meter 7 may be battery-powered, may be powered by an AC outlet, may include a supercapacitor, and may include on-board power supply circuitry (not explicitly shown).

[0303] The image sensor 11 can be a CCD sensor, a CMOS sensor, or other image sensor. The image sensor 11 captures an image of the drip chamber 4 and transmits the image data corresponding to the captured image to the processor 15.

[0304] The processor 15 is also coupled to the free-flow detector component 12, the flow estimator component 13, the control component 14, and the exposure component 29. The free-flow detector component 12, the flow estimator component 13, the control component 14, and the exposure component 29 can be implemented as processor-executable instructions, which can be executed by the processor 15 and can be stored in memory such as non-transitory processor-readable memory, ROM, RAM, EEPROM, hard disk, hard disk drive, flash drive, etc.

[0305] The processor 15 is capable of executing these instructions from the free-flow detector component 12 to determine whether a free-flow condition exists within the infusion chamber 4 by analyzing image data from the image sensor 11. Embodiments of the free-flow detector component 12 for detecting free-flow conditions are described below. In response to a detected free-flow condition, the processor 15 is capable of making a function call to the control component 14 to send a signal to the valve 6 to completely stop the fluid flow to the patient 3. That is, if the free-flow detector component 12 determines that a free-flow condition exists, the flow meter 7 can instruct the valve 6 to stop the fluid flow, can instruct the monitoring client 8 to stop the fluid flow (which can communicate with the valve 6 or the pump 414), and / or can instruct the pump 414 to stop pumping or block the fluid flow using an internal safety plug.

[0306] The flow estimator component 13 uses image data from the image sensor 11 to estimate the flow rate of the fluid flowing through the drip chamber 4. The processor 15 transmits the estimated flow rate to the control component 14 (e.g., via a function call). Various embodiments of flow rate estimation are described below. If the flow estimator component 13 determines that the flow rate is greater than a predetermined threshold or outside a predetermined range, the flow meter 7 may instruct the valve 6 to stop the fluid flow (which may communicate with the valve 6 or the pump 414), may instruct the monitoring client 8 to stop the fluid flow (which may communicate with the valve 6 or the pump 414), and / or may instruct the pump 414 to stop pumping or block the fluid flow using an internal safety plug.

[0307] Processor 15 controls LED array 20 to provide sufficient illumination for image sensor 11. For example, exposure unit 29 can be used by processor 15 or in combination with processor 15 to control LED array 20, such that image sensor 11 captures sufficient image data for use by free-flow detector unit 12 and flow estimator unit 13. Processor 15 can implement exposure algorithms stored by exposure unit 29 (see...). Figure 2 This controls the lighting conditions and / or the exposure of the image sensor 11 (when generating image data). Alternatively, the exposure component 29 can be implemented as a circuit, integrated circuit, CPLD, PAL, PLD, hardware description language-based implementation, and / or software system.

[0308] The control unit 14 calculates the adjustment to valve 6 based on the flow rate estimated from the flow estimator unit 13. For example, and as previously mentioned, the control unit 14 can implement a PID control algorithm to adjust valve 6 to achieve the target flow rate.

[0309] In some embodiments, the monitoring client 8 monitors the operation of the system 1. For example, when free-flow conditions are detected by the free-flow detector component 12, the monitoring client 8 can wirelessly transmit a signal to the valve 6 to interrupt the fluid flow to the patient 3.

[0310] In addition, the flow meter 7 may additionally include various input / output devices to promote patient safety, such as various scanners, and may communicate with electronic medical records, medication error reduction systems, and / or facility services such as inventory control systems using the transceiver 9.

[0311] In a particular exemplary embodiment, the flow meter 7 has a scanner, such as an RFID interrogator that queries an RFID tag attached to the fluid reservoir 2 or a barcode scanner that scans the barcode of the fluid reservoir 2. The scanner can be used to determine whether the fluid in the fluid reservoir 2 is correct, whether the therapy programmed into the flow meter 7 corresponds to the fluid in the fluid reservoir 2, whether the fluid reservoir 2 is correct, and / or whether the fluid reservoir 2 and the flow meter 7 are correct for a particular patient (e.g., determined from the patient's barcode, the patient's RFID tag, or other patient identification).

[0312] For example, flow meter 7 can scan the RFID tag of fluid reservoir 2 to determine whether the serial number or fluid type encoded within the RFID tag is the same as indicated by the programmed therapy stored within flow meter 7. Additionally or alternatively, flow meter 7 can query the serial number of the RFID tag of fluid reservoir 2 and the patient serial number of the RFID tag of patient 3, and also use transceiver 9 to query the electronic medical record to determine whether the serial number of fluid reservoir 2 attached to the RFID tag of fluid reservoir 2 matches the patient serial number attached to the RFID tag of patient 3 as indicated by the electronic medical record.

[0313] Alternatively, the monitoring client 8 can scan the RFID tag on the fluid reservoir 2 and the RFID tag on the patient 3 to determine whether the fluid in the fluid reservoir 2 is correct, whether the therapy programmed into the flow meter 7 corresponds to the fluid in the fluid reservoir 2, and whether the fluid reservoir 2 is correct for a particular patient (e.g., determined from the patient's barcode, RFID tag, electronic medical record, or other patient identification or information). Alternatively, the monitoring client 8 or the flow meter 7 can query the electronic medical record database and / or the pharmacy to verify a prescription or download a prescription, for example, using the serial number of the barcode on the fluid reservoir 2 or the RFID tag attached to the fluid reservoir 2.

[0314] Figure 2 An example of an exposure image sensor is shown according to an implementation of this disclosure. Figure 1 A flowchart of method 21 for image sensor 11. Method 21 includes actions 22, 23, 24, and 25. Method 21 can be... Figure 1 The processor 15 (e.g., as exposure component 29) implements and can be implemented as a processor-implemented method, configured for execution by one or more processors, in hardware, in software, or some combination thereof.

[0315] Action 22: Select the area of ​​interest. For example, refer to [reference point]. Figure 1Image sensor 11 includes a field of view containing the drip cavity 4. However, the drip cavity 4 may not occupy the entire field of view of image sensor 11. Action 22 selects only the pixels of image sensor 11 that represent, for example, the drip cavity 4.

[0316] Action 23 determines whether a pixel is within the region of interest 23. If the pixel of action 23 is one that causes, for example, the drip cavity 4 to be imaged, then action 23 determines that the pixel is within the region of interest. Similarly, in this example, if the pixel of action 23 is one that does not cause the drip cavity 4 to be imaged, then action 23 determines that the pixel is not within the region of interest.

[0317] If the pixel is within the area of ​​interest, then action 24 activates the backlight, for example, Figure 1 The backlight 18 is used. Pixels of the image sensor can be exposed at different times. Therefore, the backlight 18 can be activated only when pixels within the region of interest are exposed. For example, some image sensors include vertical and horizontal sync signals. The backlight can be synchronized with these signals to turn on when a pixel of interest is exposed.

[0318] In some embodiments of this disclosure, subgroups of LEDs for the backlight (e.g., subgroups of LED array 18, which may be a 2D array) may be turned on. If a pixel is within the region of interest, the subgroup may be a sufficient subgroup to fully illuminate the exposed pixel.

[0319] Action 25 exposes the pixel. If it is determined in Action 23 that the pixel is within the area of ​​interest, the pixel will be exposed, and at least a portion of the backlight will be turned on in Action 25. Alternatively, if it is determined in Action 23 that the pixel is not within the area of ​​interest, the pixel will be exposed, and at least a portion of the backlight will be turned off in Action 25.

[0320] Figure 3 Description of embodiments according to this disclosure Figure 2 Timing of embodiments of the method Figure 29 Timing Figure 29 This includes traces 26, 27, and 28. Trace 26 is the vertical synchronization signal from the image sensor, and trace 27 is the signal from the image sensor (e.g., ...). Figure 1 The horizontal synchronization signal of the image sensor 11. Circuit or software routines (e.g., existing in...) Figure 1 The exposure component 29 in the flow meter 7 can use synchronization traces 26, 27 to generate a backlight enable signal 28, which is used to activate the backlight or its subgroup.

[0321] Figures 4A-4B An illustration showing image data of a flow meter 7 according to an embodiment of the present disclosure, the illustration being based on... Figure 3 The timing diagram Figure 2Examples of the method. Figure 4A The diagram shows the situation when not using Figure 2 and Figure 3 In the case of the exposure algorithm illustrated in the diagram, the flow meter, such as Figure 1 Image data acquired by flow meter 7; Figure 4B The diagram is in use Figure 2 and Figure 3 The image data is acquired by the flow meter in the case of the exposure algorithm illustrated in the diagram. Illumination is provided for capturing... Figure 4A Compared to the image, in Figure 4B During image capture, providing illumination requires less power because less backlight is used.

[0322] Figure 5 The illustration shows a flow meter 67 and a valve 71 integrated together according to an embodiment of the present disclosure for coupling to a drip chamber 409 and an IV bag 69. The flow meter 67 includes an optical drop counter 68 that receives fluid from the IV bag 69. The optical drop counter 68 may be an image sensor, a pair of image sensors, a capacitive drop counter, and / or the like. The flow meter 67 is coupled to a tube 70, which is coupled to a roller clamp 71 controlled by a motor 72. The motor 72 is coupled to a lead screw mechanism 73 to control the roller clamp 71 via interaction with an interaction member 74.

[0323] Motor 72 can be a servo motor and can be used to regulate the flow rate through pipe 70. That is, flow meter 67 can also function as a flow meter and regulator. For example, processor 75 within flow meter 67 can regulate motor 72 such that the desired flow rate, as measured by optical droplet counter 68, is achieved. Processor 75 can use optical droplet counter 68 as, for example, its output supplied to feedback of a PID control loop for motor 72 and feedback received from optical droplet counter 68 to implement a control algorithm.

[0324] In alternative embodiments, the motor 72, the lead screw mechanism 73, and the roller clamp 71 can be replaced and / or supplemented with the actuator of the extrusion tube 70 (e.g., using a motor-driven cam mechanism or linkage), or they can be replaced with any sufficient roller, screw, or motor-driven slider. For example, in some embodiments of this disclosure, the roller clamp 71 can be replaced with any valve as described herein, including valves with two C-shaped members, valves with two curved support members, valves with two flexible tabs, valves clamped on the tube over a significant length of the tube, etc.

[0325] The flow meter 67 may also optionally include a display. The display can be used to set a target flow rate, display the current, and / or provide a knob (e.g., a touchscreen knob) to stop the flow.

[0326] Figure 6 This is a block diagram of an imaging system 78 for imaging a flow meter for imaging a drip cavity, according to an embodiment of this disclosure. Figure 6 The imaging system 78 shown can be used in any flow meter described herein, which includes... Figure 1 Flow meter 7 and / or Figure 5 Flow meter 67.

[0327] Figure 6 The imaging system 78 includes an image sensor 63, a uniform backlight 79 that emits light at least partially through the drip cavity 59, and an infrared (“IR”) filter 80 that receives light from the uniform backlight 79.

[0328] System 78 also includes a processor 90, which can be operated coupled to image sensor 63 and / or uniform backlight 79. Processor 90 implements algorithms to determine when free-flow conditions exist and / or to estimate flow rate (e.g., using...). Figure 1 The processor 90 may be operatively communicable with a processor-readable memory 91 (e.g., a non-transitory processor-readable memory) to receive one or more instructions to implement an algorithm to determine the presence of a free-flow condition and / or to estimate the flow rate. One or more instructions from the processor-readable memory 91 are configured to be executed by the processor 90.

[0329] The uniform backlight 79 may be an array of light-emitting diodes (“LEDs”) of the same or different colors, a light bulb, a window for receiving ambient light, an incandescent lamp, etc. In some embodiments, the uniform backlight 79 may include one or more point light sources.

[0330] Processor 90 can modulate a uniform backlight 79 according to image sensor 63. For example, processor 90 can activate uniform backlight 79 for a predetermined time period and signal image sensor 63 to capture at least one image, and then signal uniform backlight 79 to turn off. One or more images from image sensor 63 can be processed by processor 90 to estimate flow rate and / or detect free flow conditions. For example, in one embodiment of this disclosure, system 78 monitors the size of droplets formed in drip chamber 59 and counts the number of droplets flowing through drip chamber 59 within a predetermined time period; processor 90 can calculate the average value of the periodic flow of individual droplets over a period of time to estimate flow rate. For example, if droplets X, each having a volume Y, flow through drip chamber in time Z, the flow rate can be calculated as (X*Y) / Z.

[0331] Alternatively or additionally, system 78 can determine when IV fluid is flowing through the drip chamber 59 (i.e., during free-flow conditions). A uniform backlight 79 illuminates the drip chamber 59 to provide sufficient illumination for image sensor 63 to image the drip chamber 59. Image sensor 63 is capable of capturing one or more images of the drip chamber 59.

[0332] Other orientations and configurations of system 78 can be used to interpret the orientation and output characteristics of the uniform backlight 79, the sensitivity and orientation of image sensor 63, and ambient light conditions. In some embodiments of this disclosure, processor 90 implements algorithms that utilize the uniformity of images collected by image sensor 63. Uniformity can be facilitated by the uniform backlight 79. For example, when utilizing a uniform backlight 79, image sensor 63 can capture a consistently uniform image.

[0333] Ambient lighting can cause inconsistencies in the images received from image sensor 63; for example, direct sunlight provides inconsistent illumination because the sun may be intermittently obscured by clouds and the brightness and angle of the sun depend on the time of day. Therefore, in some embodiments of this disclosure, an IR filter 80 may optionally be used to filter out some ambient light to reduce variations in the images captured by image sensor 63. The IR filter 80 may be a narrowband infrared filter placed in front of image sensor 63; and a uniform backlight 79 may emit light at a wavelength approximately the same as the center frequency of the passband of filter 80. The IR filter 80 and the uniform backlight 79 may have a center frequency of approximately 850 nanometers. In some embodiments, imaging system 78 may be surrounded by a visually translucent but IR-blocking housing. In alternative embodiments, other optical frequencies, bandwidths, center frequencies, or filter types may be utilized in system 78.

[0334] Figure 7 It is based on the embodiments of this disclosure. Figure 6 A schematic illustration of image 81 captured by image sensor 63 of system 78. Image 81 is an image of drip chamber 59 showing condensation 82 and flow 83 caused by free-flow conditions therein. In some embodiments, edge detection may be used to determine the location of flow 83 and / or condensation 82. Additionally or alternatively, a background image or pattern may be used.

[0335] Figure 8 This is a block diagram of an imaging system 84 for imaging a flow meter of a drip chamber according to embodiments of the present disclosure. The imaging system 84 can be used with any flow meter disclosed herein, including... Figure 1 Flow meter 7 and Figure 5 Flow meter 67.

[0336] System 84 includes an opaque linear array 85 downstream of the drip chamber 59. System 84 uses the linear array 85 to detect free-flow conditions. Free-flow detection algorithms (e.g., Figure 1 The free-flow detector component 12) can use the presence or absence of droplets to determine whether fluidization conditions (e.g., free-flow conditions) exist.

[0337] In some specific embodiments, the line 85 is present only on a small portion of the image (e.g., the background pattern occupies only a small portion of the backlight 18, or the binary optics cause the pattern to appear only in a portion of the image (such as the lower or upper half). For example, a small portion of the lower half of the image may include a striped background pattern.

[0338] Now refer to Figure 9 According to embodiments of this disclosure, when free-flow conditions exist in the drip chamber 59, the diagram of image 86 is shown as being composed of... Figure 8 Image 86 is captured by image sensor 63. Image 86 illustrates the free-flow conditions experienced by the drip chamber 59 and the effect of the fluid flow 87 acting as a positive cylindrical lens. That is, as... Figure 9 As shown, compared to non-free-flow conditions, the line array 85 in the image captured by image sensor 63 is shown as a reversed line pattern 88 from the line array 85. The appearance of the reversed line pattern 88 is caused by the change in light as it approaches image sensor 63 and passes through fluid flow 87.

[0339] In some embodiments of this disclosure, illumination generated by light having an optical wavelength of approximately 850 nanometers can be used to create image 86. Some materials may be opaque in the visible spectrum and transparent in the near-IR spectrum of approximately 850 nanometers, and therefore these materials can be used to create linear array 85. Linear array 85 can be created using a variety of rapid prototyping plastics. For example, linear array 85 can be created using a rapid prototyping structure printed with infrared-opaque ink or coated with metal to realize linear array 85. Additionally or alternatively, in some embodiments of this disclosure, another method of creating linear array 85 is to create a circuit board in which the lines are laid in copper. In another embodiment, linear array 85 is generated by laying a ribbon cable over a uniform backlight 79; the wires in the ribbon cable are opaque to the infrared spectrum, but the insulator is transparent, such that the spacing of the wires can form lines for use during imaging through image sensor 63 (see [link]). Figure 8 In other embodiments, a thin sheet of electrically discharge-processed (EDMed) metal can be used. The metal is opaque to light, and the spaces between the metal material deposits can be very precisely controlled during manufacturing to allow IR light to pass through these spaces.

[0340] Processor 90 implements an algorithm to determine when free-flow conditions exist (e.g., using...). Figure 1 The processor 90 is operatively communicable with a processor-readable memory 91 (e.g., a non-transitory processor-readable memory) to receive one or more instructions to implement an algorithm to determine whether a free-flow condition exists. One or more instructions from the processor-readable memory 91 are configured to be executed by the processor 90.

[0341] Refer again Figure 8 System 84 can use blood. For example, when using an image sensor 63 configured to use visible light with wavelengths of 850 nm or 780 nm, an IR filter 80, and a uniform backlight 79, for example, when using bovine blood, system 84 can determine when free-flowing conditions of blood are present. Blood may appear opaque compared to images taken using water.

[0342] The following algorithms, implemented by processor 90 and received from processor-readable memory 91, can be used to determine when the free-flow condition exists: (1) Establishing a background image 89 (see Figure 10 (1) Subtract the current image from the background image 89; and (2) Subtract the current image from the background image 89. In addition, processing can be performed on the resulting image.

[0343] In some embodiments of this disclosure, Figure 10 The background image 89 can be dynamically generated by the processor 90. The dynamic background image can be used to interpret changing conditions, such as condensation or splashes 82 on the surface of the drip chamber 59 (see [link to relevant documentation]). Figure 7 For example, in one specific embodiment, for each new image captured by the image sensor (e.g., Figure 8 (63) The background image has each pixel multiplied by 0.96, and the current image (e.g., the most recently captured image) has the corresponding pixel multiplied by 0.04. These two values ​​are added together to create a new value for the new background image for that corresponding pixel; this process can be repeated for all pixels. In yet another example, in one specific embodiment, if the pixels of the new image are in row x and column y, then the new background image in row x and column y is the value of the previous background image in row x and column y multiplied by 0.96 plus the value of the new image's pixels in row x and column y multiplied by 0.04.

[0344] When there is no water flowing through the drip chamber 59 in system 84 (see...) Figure 8 When the subtraction is performed, the resulting image should be almost entirely black, i.e., low pixel size, thus enabling the algorithm to determine that no water flows through the drip chamber 59.

[0345] Figure 11Image 92 from image sensor 63 is shown when a droplet is present in the dripping chamber 59 (see image 92). Figure 8 ). Figure 12 This shows the background image 93 used by system 84. When system 83 has such Figure 11 When the droplets are shown in image 92, Figure 8 The system 84 has several high-contrast points, where the image of the linear array is distorted by the lensing effect of droplets, as if... Figure 13 Image 94 illustrates this. Figure 13 Image 94 is obtained by taking each corresponding pixel from Figure 12 Image 93 minus Figure 11 The image is generated by taking the absolute value of 92 and converting each corresponding pixel to a white pixel if the value is above a predetermined threshold, or converting the pixel to a black pixel if the value is below the predetermined threshold. Figure 13 Each white pixel in image 94 is a result of the difference in pixel position between images 92 and 93 for pixels whose positions are greater than a predetermined threshold.

[0346] For example, consider Figure 11 , Figure 12 ,and Figure 13 Three corresponding pixels with row x and column y positions. To determine Figure 13 The image has 94 pixels in row x and column y, from... Figure 12 The pixels at row x and column y of image 92 minus the pixels at... Figure 11 The pixels at row x and column y of image 92 are calculated, and then the absolute value of the subtraction is taken; and if the absolute value of the result is above a predetermined threshold (e.g., above a grayscale value of 128, for example), then... Figure 13 In image 94, the pixels at row x and column y are white; otherwise, they are white. Figure 13 The pixels at row x and column y positions in image 94 are black.

[0347] When determined in Figure 13 When image 94 contains several high-contrast spots, the processor 90 of system 84 (see...) Figure 8 It was determined that the droplet formed within the drip chamber 59 and that no free-flow conditions existed. The droplet size could be determined using an image of the droplet to estimate the flow rate as described herein.

[0348] Figure 14 It is possible to use according to embodiments of this disclosure Figure 11-13 A graphical representation of some image processing performed to determine the existence of free-flow conditions. (Refer to...) Figure 14 and Figure 13 All the white pixels in each row are added together, and Figure 14The middle image shows result 183. The y-axis represents the number of rows, and the x-axis represents the sum of the white pixels in each corresponding row.

[0349] Now only for reference Figure 14 As previously mentioned, the number of white pixels in each row is summed and illustrated as result 183, which is used to determine whether or when a free-flow condition exists. In some specific embodiments, when a predetermined number of consecutive values ​​of the summed rows of result 183 exceed a threshold 184, the processor 90 of system 84 (see [link to relevant documentation]) [context missing]. Figure 8 The existence of free-flow conditions is determined. For example, within result 183, the range of multiple consecutive rows, generally represented by 185, has a total value above a threshold 184. When a predetermined number of consecutive summed rows are determined to exist within result 183 above a predetermined threshold (e.g., threshold 184), Figure 8 The processor 90 determines that the free-flow condition exists. For example, such as... Figure 14 As shown, the range of multiple consecutive summation rows 185 is below a predetermined number of consecutive summation rows (i.e., the range 185 is not wide enough) and therefore it is determined that the free flow condition does not exist.

[0350] Figure 15 This shows that when the free-flow condition exists, by Figure 8 The image sensor 63 captures an image 95 showing the flow. Figure 16 Background image 96 is shown. Figure 17 This illustrates how the difference is converted to white pixels (when the absolute value of the difference is above a threshold) or to black pixels (when the absolute value of the difference is below a threshold) by... Figure 16 Image 96 and Figure 15 Image 97 is formed by the absolute value of the difference between images 95 and 95. (Example: ...) Figure 17 As shown, processor 90 can detect high-contrast spots caused by the reverse orientation of lines in a downward-flowing stream. Figure 8 The processor 90 is able to use image 97 to determine whether the free-flow condition exists using the algorithm described above.

[0351] That is, such as Figure 18 As shown, result 186 is presented as a continuous range 187 of result 186 that is above threshold 188. Because the summation row of continuous range 187 is greater than a predetermined number of consecutive values ​​above threshold 188, processor 90 determines that a free-flow condition exists (see [reference]). Figure 8 That is, the continuous range of results 186 above the threshold 188 is greater than the predetermined threshold range of continuous values; therefore, when processor 90 uses... Figure 18 The result at time 186 confirms the existence of the free flow condition.

[0352] In other embodiments of this disclosure, intensity, the square of intensity, or other functions may be used to generate Figure 14 Result 183 and / or Figure 18 The result is 186. In another embodiment, one or more data smoothing functions may be used to smooth the results 183 and / or 186, such as a sample function, a cubic sample function, a B-sample function, a Bezier sample function, a polynomial interpolation, a moving average, or other data smoothing functions.

[0353] For example, it can be derived from a background image (e.g., Figure 16 Image 96) Subtract Figure 8 Images from image sensor 63 (e.g., Figure 15 The intensity value can be obtained from the image (95). That is, it can be obtained from... Figure 16 The number of pixels in row x and column y of the image 96 minus Figure 15 The pixels in row x and column y are used to create intensity values ​​at row x and column y; this process can be repeated for all pixel locations to obtain all intensity values. The intensity values ​​for each row can be summed to obtain results 183 and / or 186 (see [link to relevant documentation]). Figure 14 and 18 The processor 90 can determine that a free-flow condition exists when the intensity values ​​of the summed rows have a continuous range of summed rows that are above a threshold. In some embodiments, the intensity values ​​are converted to absolute values, and the intensity values ​​of the absolute values ​​of the summed rows are used to determine whether a continuous range of summed rows of absolute values ​​is above a threshold range of continuous values. Alternatively, the intensity can be squared, and the processor 90 can sum the squared intensity rows and determine whether there is a continuous range of summed rows of squared intensity values ​​that exceed a threshold range of continuous values ​​to determine whether a free-flow condition exists.

[0354] In some embodiments, processor 90 may use a predetermined range (e.g., minimum and maximum ranges) of consecutive values ​​above a threshold of the summation row of intensity values ​​or intensity squares to determine whether a droplet is within the image. For example, each row of intensity values ​​(or intensity squares) may be summed, and the range of summations may be above a threshold number; if the range of consecutive values ​​is between the minimum and maximum ranges, processor 90 may determine that the range of consecutive values ​​above the predetermined threshold is a droplet within the field of view of image sensor 63 (see [link to image sensor 63]). Figure 8 In some embodiments of this disclosure, the summation row of intensity values ​​or intensity squared values ​​may be standardized, for example, to have values ​​between 0 and 1.

[0355] The following describes a smoothing function similar to cubic skewing (i.e., a cubic skewing-type function), which can be used on the summation row, the summation row of intensity values, or the summation row of squared intensity values ​​to determine whether a free-flow condition exists before being determined by processor 90. In some specific embodiments, the cubic skewing-type function can be used to identify blocks, as described below, which can facilitate the identification of free-flow conditions by processor 90.

[0356] A cubic stenographic type function is a simulation of cubic stenography, but it smooths the data set rather than faithfully mimicking the given function. It samples the data from [0,1] at intervals (e.g., along the normalized square of the intensity or the sum of the intensity rows), and the processor 90 (see...) Figure 6 or Figure 8 ) can be in intervals [x0,x1],[x1,x2],...,[x N-1 ,x N (x0 = 0, and x) N =1) Find the best-fitting set of cubic functions, where the total function is continuous with continuous derivatives and continuous curvature.

[0357] The standard cubic model is defined in equation (1) as follows:

[0358] χ(x)=A i (x)y i +B i (x)y i+1 +C i (x)y″ i +D i (x)y″ i+1 x i ≤x≤x i+1 (1),

[0359] In equation system (2), function A i B i C i D i Defined as:

[0360]

[0361]

[0362] Equations (1) and (2) guarantee continuity and curvature continuity. The only freely selectable value is y. i y″0 and y″ N Please note that equation (3) is chosen as follows:

[0363] y″0=y″1=0 (3),

[0364] That is, the function is flat at 0 and 1. The remaining y″ i The following system of equations (4) must be satisfied:

[0365] The system of equations (4) can be rewritten as the system of equations (5) as follows:

[0366]

[0367] This then becomes the matrix equation (6):

[0368]

[0369] The matrix equation (6) can be rewritten as the system of equations (7) as follows:

[0370] Fy dd =Gy

[0371] y dd =F -1 Gy=Hy(7)

[0372] The least squares criterion is used to select the values ​​in vector y from the collected data, as explained in equation (8):

[0373]

[0374] Equation (8) represents the minimum deviation between the data and the sample; that is, equation (8) is the error function. The y-value is chosen to minimize the error as defined in equation (8). The vector of predicted values ​​can be written as shown in equation (9) as follows:

[0375]

[0376] The elements of the matrix within the parentheses in equation (9) depend on the x-values ​​corresponding to each data point (however, this is a fixed matrix). Therefore, the pseudo-inverse can be used to determine the final equation. Furthermore, the pseudo-inverse depends only on the x-position of the data set and the location where the breakpoints in the cubic stencil are set. This implies that once the geometry of the stencil and the size of the image are chosen, for a given set of measurements y... m The optimal choice of y is explained in equation (10) as follows:

[0377] y = (A T A) -1 A·y m (10).

[0378] The cubic modeling of the sum and square function of the image will thus be given by equation (11) as follows:

[0379] y cs=A·y (11).

[0380] Since the maximum value of the cubic simulation is of interest, we determine the derivative of the cubic simulation and use this derivative to determine the maximum value of the cubic simulation. The derivative of the cubic simulation is given by equation (12) as follows:

[0381]

[0382] Equation (12) can be written as equation (13) as follows:

[0383] y′ cs =(A′) {k} +B′ {k} )y+(C′ {k} +D′ {k} )y dd

[0384] =[A′ {k} +B′ {k} +C′ {k} H+D′ {k} H]y

[0385] =A′y (13).

[0386] Once the current value of y is found, it is possible to calculate the three-dimensional parsing of y. cs and its derivative y' cs The three simulation data may include data “blocks” that contain values ​​above a predetermined threshold. A pipe block is formed by the liquid flowing from the pipe into the drip chamber 59, and a pool block forms as liquid collects at the gravity end of the drip chamber 59 (see [link to documentation]). Figure 8 ).

[0387] The following algorithms can be applied to cubic simulation data: (1) using derivative information to determine local maxima of the cubic simulation data; (2) determining the blocks around each local maximum by including all points where the cubic simulation values ​​are above a threshold; (3) merging all intersecting blocks; (4) calculating information about the data blocks including the centroid (intensity), the second moment of mass (intensity), the lower x-value of the block, the upper x-value of the block, the average of the initial sum of the squared intensity data in the block, the standard deviation of the initial sum of the squared intensity data in the block, and the average intensity of the high-pass filtered image group in the block; and (5) interpreting the collected data to obtain information about when droplets occur and when the system is in flow.

[0388] The average intensity of the high-pass filtered image group within a block is used to determine whether the block generated from each consecutive range of the sampled data is the result of a high-frequency artifact (e.g., droplets) or a low-frequency artifact. This acts as a second background filter, which tends to remove artifacts such as condensation from the image. That is, all previous images in the image buffer (e.g., 30 previous frames, for example) are used to determine whether the data is the result of high-frequency shifts between frames. If a block is the result of a low-frequency change, the block is removed; if a block is the result of a high-frequency change, the block is retained for further analysis. Finite impulse response (FIR) filters or infinite impulse response (IOR) filters can be used.

[0389] Each block is drawn over its physical extent, and its height is equal to the average of the data within the block. If a block has an average of a high-pass filtered image that is less than a threshold, it indicates that it has been wrapped around several images and can therefore be removed.

[0390] When a pipe block extends close to a pool block, the pipe block and the pool block merge together, and / or the sum of the widths of the pool block and the pipe block (or all blocks) exceeds a predetermined threshold, for example, when the total width of the blocks exceeds 380 pixels, processor 90 (see...) Figure 6 or Figure 8 These blocks are used to determine the presence of free-flow conditions. As a result of droplet formation in the tube and as the droplet leaves the tube (i.e., pipe) opening of the drip chamber 59, the processor 90 can detect the droplet when a transition from a wider to a shorter tube block occurs. The processor 90 can detect the droplet by looking at the ratio of the current tube block width to the tube block width of a previous image; for example, an image where this ratio is less than 0.9 (also a local minimum) can be considered by the processor 90 as an image formed immediately after the droplet has formed.

[0391] Various filtering algorithms can be used to detect condensation or other low-frequency artifacts, such as: if a block has a low average value in a high-pass filtered image, it may be condensation. Such artifacts can be removed from consideration. Additionally or alternatively, long blocks with low high-pass average values ​​(e.g., greater than a predetermined threshold) may be flow, as flow images tend to remain unchanged; processor 90 can determine that long blocks greater than the predetermined threshold correspond to flow conditions. Additionally or alternatively, algorithms can be used on the current image to detect free-flow conditions.

[0392] In some specific embodiments, processor 90 may use block data to count droplets to use system 84 as a droplet counter. When droplets disturb the water, processor 90 may also use the width change in the pool blocks to determine whether bubbles formed by droplets are impacting the pool. For example, processor 90 may determine that those blocks formed below the pool blocks originate from bubbles formed when droplets impact the water. When a predetermined value for the total block range indicates that free-flow conditions are present, processor 90 filters out the bubbles.

[0393] In some embodiments of this disclosure, the system 84 may have a narrow depth of field so that the system 84 is less sensitive to condensation and droplets on the cavity walls. In some embodiments, a near-focus system may be used.

[0394] Now refer to Figure 19 In another embodiment of this disclosure, template 189 is used to determine whether a free-flow condition exists. When in an image (e.g., Figure 13 When performing template matching algorithm on image 94), Figure 8 The processor 90 uses template 189 to determine pattern matching score 190. For example, module 189 can be compared with image 94 to determine whether part or all of image 94 closely matches module 189. As previously mentioned, Figure 13 Image 94 is the background image and Figure 8 The difference between images captured by image sensor 63 is used to convert each pixel to a black pixel if the difference is below a threshold, or to a white pixel if the difference is above a threshold. All pixels of image 94 will be either white or black pixels. If the pattern matching score 190 is above a predetermined threshold, the free-flow condition is determined to exist. The template matching method can utilize template matching algorithms found in the Open Source Computer Vision (“OpenCV”) library. For example, template 189 can be used with the matchTemplate() function call of the OpenCV library using the CV_TM_CCOEFF method or the CV_TM_CCOEFF_NORMED method. The CV_TM_CCOEFF method uses the pattern matching algorithm described in equation (14) as follows:

[0395] in:

[0396] T′(χ′,y′)=T(χ′,y′)-1 / (w·h)·∑ χ″，y″ T(χ", y")

[0397] I′(x+χ′,y+y′)=I(χ+χ′,y+y′)-1 / (w·h)·∑ x″，y″ I(x+χ", y+y")

[0398] I represents the image, T represents the template, and R represents the result. Summation is performed on the template and / or image patches such that: x′=0...w⁻¹ and y′=0...h⁻¹.

[0399] The result R can be used to determine the degree of matching of template T at a specific location within image I, as determined by the algorithm. The OpenCV template matching method of CV_TM_CCOEFF_NORMED uses the pattern matching algorithm described in equation (15) as follows:

[0400]

[0401] In another embodiment of this disclosure, the template matching algorithm uses a Fast Fourier Transform (“FFT”). In some embodiments, any method of the OpenCV matchTemplate() function can be used, such as CV_TM_SQDIFF, CV_TM_SQDIFF_NORMED, CV_TM_CCORR, and / or CV_TM_CCORR_NORMED.

[0402] CV_TM_SQDIFF uses the pattern matching algorithm described in equation (17) as follows:

[0403]

[0404] CV_TM_SQDIFF_NORMED uses the pattern matching algorithm described in equation (18) as follows:

[0405]

[0406] CV_TM_CCORR uses the pattern matching algorithm described in equation (19) as follows:

[0407]

[0408] CV_TM_CCORR_NORMED uses the pattern matching algorithm described in equation (20) as follows:

[0409]

[0410] In another embodiment of this disclosure, a template of a grayscale image under free-flow conditions is combined with a template of a grayscale image derived from... Figure 8 The image sensor 63 is compared with the image acquired to determine whether a free-flow condition exists. In some embodiments, template matching functions within the OpenCV library can be utilized.

[0411] Now refer to Figure 20 and Figure 21 In other embodiments of this disclosure, for example, as by Figure 8 The processor 90 executes an algorithm to determine when free-flow conditions exist. This algorithm can be used to determine whether a template pattern matches a pixel array using edge detection followed by line detection. For example... Figure 20As shown, by using the detected edges followed by line detection, image 98 is... Figure 21 Image 99 is formed. Processor 90 can use the obtained lines to determine whether free-flow conditions exist. For example... Figure 20 As shown, the feature exhibited after this processing by processor 90 is a line with a slope different from the expected 45° slope of the background reference image. In some embodiments, it can be derived from... Figure 20 These lines, which have angles relative to the background image, are filtered out. The Canny algorithm, found in the OpenCV library, can be used to detect the lines as edges. The Hough algorithm, also found in the OpenCV library, can be used to determine the slope of the lines.

[0412] One type of Hough transform uses the algorithm described in the Progressive Probabilistic Hough Transform published by J. Matas, C. Galambos, and J. Kittler in 1998 (“Algorithm 1”). However, the following “alternative Hough” transform can be utilized and is shown in pseudocode in Table 1 (“Algorithm 2”). Algorithm 2 randomly selects two pixels and computes the Hough transform of the line passing through these two points. Algorithm 2 is shown in Table 1 as follows:

[0413]

[0414] If the line includes a proportion p of the total points, then the result in the representative (r,θ) binary representation will be p for Algorithm 1 and p for Algorithm 2. 2 Generally, in some embodiments, the proportional trial has at least 5 positive results and 5 negative results. Assuming that negative results are more likely to be seen than positive results, in some embodiments, Algorithms 1 and 2 continue searching the line until at least 5 positive results exist in a given binary.

[0415] The probability of seeing a fifth positive result in Algorithm 1 after N≥5 trials is shown in equation (21) as follows:

[0416]

[0417] And the possibilities in Algorithm 2 are shown in equation (22) as follows:

[0418]

[0419] Table 2 below shows that there is a 50% chance of seeing 5 successful results. 1,50 and p 2,50 The number of trials and a 90% chance of seeing 5 successful results. 1,90 and p 2,90The number of trials.

[0420]

[0421] Table 2 shows that increasing the number of trials between Algorithm 1 and Algorithm 2 to see 5 positive results is approximately 1 / p. When the ratio is p, there will be 1 positive result in 1 / p trials.

[0422] In some embodiments, the computationally intensive operation of Algorithm 2 is the arctangent function, which may require approximately 40 floating-point CPU operations. The equivalent step of Algorithm 1' involves approximately 2N floating-point operations. The Hough transform of a 640×480 pixel image at full resolution has N equal to 2520, while the Hough transform of a 1080×1920 pixel image has N equal to 7020. This means that for a 640×480 image when p is greater than 0.008, and for a 1080×1920 image when p is greater than 0.003, Algorithm 2 has a speed advantage over Algorithm 1.

[0423] In some embodiments, it is assumed that each binary in the Hough transform space is equally likely to be occupied in the presence of noise. This simplification speeds up threshold determination; however, in some embodiments, this assumption does not hold. The initial effect of this simplification is to underestimate the probability of seeing a value greater than 1 in the Hough transform due to the falsely reported probability of the presence of a corresponding line. For a specific combination of image size and Hough transform binary permutations, the true probability can be pre-calculated. This allows minimizing the false alarm rate without a corresponding increase in computation. With additional constraints on the type of imaging, even more accurate estimates of the probability of seeing a value in the Hough transform binary are possible.

[0424] There are other forms of the Hough transform that parameterize different features. For example, there exists a ternary parameterization for a circle (x, y, r), where x and y specify the center and r is the radius. Algorithm 2 can also work using these parameterizations. For the circle example, Algorithm 2 will randomly select three pixels and compute a circle passing through them.

[0425] Algorithm 2 will have a similar speed advantage for features that include a significant portion of the total number of pixels considered. It will also have a significant advantage in terms of storage requirements, since the Hough transform can be stored in a sparse matrix, whereas the simulation of Algorithm 1 would require a full-size matrix.

[0426] Now refer to Figure 22-26 , Figure 22-26 This describes various background patterns that can be used to detect free-flow conditions or estimate the size of liquid droplets. The image sensor 103 can be used with... Figure 22-26 Background patterns can be used together and can be Figure 1 Image sensor 11 Figure 5 Image sensor 68 Figure 6 Image sensor 63, or Figure 8 Image sensors 63, each of which can be coupled to a corresponding processor (such as, Figure 1 Processor 15 or Figure 8 The processor 90) is used to process images from the image sensor.

[0427] Figure 22 It is according to embodiments of the present disclosure for use with the drip chamber 104 (e.g., Figure 1 A block diagram of an imaging system 100 used in conjunction with a droplet cavity 104 and a light source 102. The droplet cavity 104 has a striped background pattern 101, and the light source 102 illuminates the stripes from a position adjacent to the image sensor 103. Any droplet or free flow within the droplet cavity 104 distorts the image acquired by the image sensor 103. A processor (e.g., [missing information]) is coupled to the image sensor 103. Figure 1 The processor 15) is able to use deformations of the background pattern 101, such as those captured by the image sensor 103, to estimate flow rate and / or detect free-flow conditions.

[0428] Figure 23 This is a block diagram of an imaging system 105 for use with a drip chamber 104 and a light source 102 according to an embodiment of the present disclosure. The drip chamber 104 has a striped background pattern 101, and the light source 102 illuminates the stripes from behind the background pattern 101 at the opposite end of the image sensor 103. Figure 24 This illustrates an embodiment of the present disclosure where a droplet causes... Figure 23 The background pattern 101 is derived from Figure 23 Images from image sensor 103. Note, as Figure 24 As shown, the stripes of the background pattern 101 are deformed (or will be deformed by free flow) by the droplets in the drip chamber 104, as captured in the image by the image sensor 103. This deformation can be used to estimate the droplet size, to calculate the flow rate through the drip chamber, or to determine whether free flow conditions exist within the drip chamber.

[0429] Figure 25 A block diagram of an imaging system according to an embodiment of the present disclosure for use with a flow meter and a light source is shown. The flow meter has a background pattern with a checkerboard pattern, and the light source illuminates the stripes from behind the background pattern at the opposite end of the image sensor. Figure 26 This illustrates an embodiment of the present disclosure where a droplet causes... Figure 25-26 The background pattern 107 is derived from Figure 25 Images from an image sensor. In yet another embodiment of this disclosure, the imaging system disclosed herein may utilize a background pattern having a plurality of random dots and / or circles.

[0430] Reference Figure 22-26 The "lensing effect" of a droplet (i.e., distortion of the background pattern in the view from an image sensor) can be used to measure the droplet's radius. The droplet's radius corresponds to how much and what kind of effect the droplet produces on any light passing through it. By measuring the change in a calibration grid (i.e., the background pattern) as seen through the droplet, the radius can be calculated, and therefore the droplet's volume can be calculated. For example, the magnification of a test grid of known size as seen through the droplet can be measured optically, and the radius can be inferred from that measurement. In some embodiments of this disclosure, the relationship between the radius and the droplet can be calculated and / or determined using a lookup table that has been generated empirically.

[0431] Figure 27-28 A flowchart illustrating a method for estimating the volume of a droplet within a dripping chamber according to an embodiment of this disclosure is shown. That is, Figure 27-28 Method 214 will also be explained. See also: Figures 29-37 Let's describe method 214. Figures 29-31 and Figure 33-36 Images used or generated by a flow meter according to embodiments of the present disclosure are shown to estimate the volume of droplets within a drip chamber. Figure 32 and Figure 37 It can be shown that it can be made by Figure 27-28 The pseudocode used in method 214.

[0432] Figure 27 and Figure 28 Method 214 can be derived from Figure 1 Flow meter 7, Figure 5 Flow meter 67 Figure 6 Imaging system 78 Figure 8 The imaging system 84, or other flow meters of the imaging system disclosed herein, are used to achieve this (each with or without a background pattern and / or with or without active illumination).

[0433] Method 214 includes actions 200-213. Action 200 determines the baseline of the droplet formed at the opening of the dripping cavity. Action 201 captures a first image. A uniform backlight can be used to acquire the first image. In some embodiments, a background pattern and / or an exposure algorithm as described herein can be used to capture the first image. Actions 200 and 201 can be performed simultaneously. Figure 29 An image showing an overlaid baseline 215 is illustrated. The baseline 215 may be a predetermined group of pixels or may be arranged on the opening of the infusion cavity and / or in the background pattern (in...). Figure 29 The reference point marker (not shown) is generated. Method 214 uses the first image to initialize the background image, μ i,j , variance array, si,j And integer arrays, I i,j The background image can have i×j pixels, while the variance array and integer array can also be 2-D arrays of size i×j.

[0434] Action 202 identifies a droplet within the first image and a predetermined band near the edge of the droplet (e.g., the band may be a predetermined number of pixels extending beyond the edge of the droplet). Action 203 initializes the background image by setting each pixel to the same value as in the first image (for that corresponding location), unless it is within the identified droplet or the predetermined band near the edge of the droplet. Action 204 sets the pixels within the area of ​​the droplet or within the predetermined band to predetermined values. Figure 30 This shows an example background image generated after initialization. Figure 30 In the exemplary image, the droplet and the area of ​​the band extending beyond the edge of the droplet are generally specified as 216 and set to a predetermined value, for example, 140.

[0435] For example, when the method generates a first background image, each pixel in the background image that is a droplet or a band outside the edge of the droplet is set to a default threshold in the intensity range of 0-255, for example, 140.

[0436] Action 205 initializes the integers in the integer array to zero. Action 206 initializes the values ​​in the variance array to zero. The integer array is the same size as the image. The integer array counts how frequently each pixel of the background image is updated with new information and initialized to zero. The variance array (e.g., an array of data type "double precision") is also the same size as the background image and contains an estimate of the intensity variance of each pixel within the background image.

[0437] Action 207 captures another image, and action 208 identifies the droplet in the other image and another predetermined band near the edge of the droplet. Action 209 updates the background image, the integer array, and the variance array.

[0438] The background image can be updated when another image is captured. For example, when the system collects images, the background algorithm evaluates each pixel. If a pixel is considered to be part of a droplet or its protective band, its value in the background image is not changed.

[0439] If a pixel is not considered part of a droplet or its protective band: (1) if the corresponding integer of the pixel in the integer array is zero, the value of the pixel in the background image is set to be equal to the value of the pixel in the input image; or (2) if the pixel count is greater than 0, a low-pass filter is used to update the background image value of that pixel. In some embodiments, any type of filter, such as a high-pass filter, a band-pass filter, etc., can be used. A low-pass filter that can be used is shown in equation (23) as follows:

[0440] P background,i,j =P background,i,j (1-α background )+α background P input,i,j (twenty three).

[0441] Furthermore, the variance array can be updated using equation (24) as follows:

[0442]

[0443]

[0444] Note that the filter used for both operations is an exponential filter; however, in other embodiments, other suitable filters, such as other low-pass filters, may be used. Variance estimation can be performed in any known manner or using alternatives for estimation (e.g., using standard error).

[0445] A new estimate of the background intensity (mean) for each pixel, the number of images used to update the mean and variance for each pixel, and the variance for each pixel (e.g., a value approximating the true variance and / or proportional to the variance) are used to update the array. That is, each additional captured image can be used to update the background image, the integer array, and the variance array. After processing several images, the background image may appear as... Figure 31 Note that the image still contains areas where the pixels have not changed from the initial threshold (uniform medium gray areas, roughly designated as 217). This area has been considered part of the droplet or its protective band in each image.

[0446] Action 210 compares another image (e.g., the current or latest image) with the background image and identifies multiple pixels of interest. Action 211 determines the subgroup of pixels corresponding to the droplet within the multiple pixels of interest.

[0447] The comparison in action 210 compares another image with the background image pixel by pixel. From this comparison, an array of the same size as the image with zero or non-zero values ​​(255) for each pixel can be obtained.

[0448] Action 210 can be performed by Figure 32The pseudocode implementation shown is as follows. Specifically, the threshold is determined according to the following: if the input pixel is to the left or right of the baseline in the image, its output value is set to zero (line 1); if the background count array of the input pixel indicates that fewer than a predetermined number of images (e.g., 100) have been used to achieve the background value of the pixel (line 2), then: if the intensity of the input pixel is less than the threshold intensity (e.g., 140 in the range of 0-255), the output value of the pixel is set to non-zero (255) (line 2a); or if the intensity of the input pixel is greater than or equal to the threshold intensity, the output value of the pixel is set to zero (line 2b); and if the background count array of the input pixel is greater than a predetermined number of images (line 3), then: if the square of the difference between the input pixel intensity and the background pixel intensity is greater than the estimate of the background variance of the pixel multiplied by a constant γ... 2 Then the output value of the pixel is set to nonzero (255) (line 3a) (that is, if the difference between the current pixel value and the background image is greater than γ, the pixel is distinct); or if the square of the difference between the input pixel intensity and the background pixel intensity is less than or equal to the estimate of the background variance of the pixel multiplied by the constant γ. 2 If the droplet is present, the output value of the pixel is set to zero (see line 3b). Line 3 captures the portion of the image that is altered by the presence of the droplet but results in higher intensity.

[0449] When action 210 is implemented as an algorithm, the algorithm is initialized, and the input and output of the threshold algorithm will look like... Figure 33 and Figure 34 The images in the image. Because the number of images used in estimating the background image is initially small, the only criterion applied is shown above lines (1) and (2), since for some corresponding pixels, there are not enough images to make the integer array have values ​​exceeding the threshold. This may cause many low-intensity areas to be identified as distinct, including under-illuminated edges and condensation on the cavity walls.

[0450] After enough images have been collected so that most (or all) of the pixels in the background image have been generated along with a sufficient number of pixels, Figure 32 Lines (3), (3a), and (3b) are utilized. After thresholding, the background is largely black and contains transient noisy pixels exceeding the variance threshold, such as... Figure 35 and Figure 36 As shown ( Figure 35 and Figure 36 The images captured by the camera and the results of the comparison algorithm described above are shown respectively.

[0451] As previously mentioned, following action 210, action 211 determines which of the pixel subgroups within the plurality of pixels of interest corresponds to the droplet. Action 211 can be performed by... Figure 37 The pseudocode implementation shown is as follows. That is, the threshold image is passed to find a representation as given by... Figure 37 The pseudocode shows the algorithm for connecting the components of the droplet.

[0452] In processing Figure 32 The pseudocode then evaluates the binary image to find the binary components that occupy the space given by the droplet. The algorithm does this by determining the position of the pixel on the white baseline (or by finding the center pixel of the longest extension of a line of consecutive white pixels).

[0453] Once the algorithm has an initial white pixel, it executes the algorithm... Figure 37 The pseudocode shown illustrates the algorithm. The pseudocode determines the position of a white pixel, including those with a path to the baseline (i.e., the white pixel path). Line 1 pushes the position of the first pixel onto the stack. While the stack is not empty, line 2 executes a while loop. The while loop consists of lines (2a)-(2d). Line 2a pops the next position (i,j) from the stack. Line 2b sets the output pixel value at (i,j) to white. Line 2c checks the 8 pixels adjacent to (i,j). Line (2ci) is an "if statement" and checks if the adjacent input pixels... White but output pixels If it is black, then line 2c will be at that position. Add to the stack. Line 2d returns to line 2 to continue the loop (if the stack remains empty).

[0454] This algorithm sets all output pixel positions to white if they can be connected to the positions of input pixels via a continuous path of white input pixels. The left boundary of the droplet is found by stepping through each row of pixels from the left edge until the algorithm hits a white pixel. The right boundary is found by stepping from the right edge of the image until it hits a white pixel. The first row that can be stepped from the left edge to the right edge without hitting a white pixel is considered the termination of the droplet.

[0455] Figure 37 The pseudocode shown is a one-pass version of the connection component labeling algorithm. However, other connection component labeling algorithms or other suitable algorithms can be used to determine which pixel corresponds to the droplet.

[0456] Figure 28 Action 212 performs a rotation operation on the pixel subgroup. Action 213 estimates the volume of the droplet in the droplet cavity by counting the number of pixels within the rotated pixel subgroup. The total number of pixels within the 3D version of the droplet is counted; and since each pixel corresponds to a distance, the number of pixels can be used to estimate the volume of the droplet.

[0457] Imaging system optical elements

[0458] Figure 38-42The following description facilitates the description of the optical elements of the imaging systems disclosed herein. For example, the image sensor disclosed herein may be an image sensor cube manufactured by OmniVision at 4275 Burton Drive, Santa Clara, California 95054; and, for example, the image sensor cube may be an image sensor cube manufactured for telephone image sensor applications. In some embodiments of this disclosure, the image sensor disclosed herein may use a fixed focal length and have a depth of field (“DOF”) from 15 cm to infinity.

[0459] An image sensor can have a blurred circle of points imaged within a region of the image sensor completely contained within a single pixel. The focal length of the image sensor lens can be 1.15 mm, the f# can be 3.0, and the aperture of the image sensor lens can be f0.3833 mm. A first-order approximation of the optical system of one or more image sensors can be achieved using matrix equations, where each ray, r, is represented as the vector described in equation (25) as follows:

[0460]

[0461] In equation (25) above, h is the height of the light ray at the entrance of the image sensor, and θ is the angle of the light ray. (Refer to...) Figure 38 When the hypothetical point is at a distance d from one of the lenses of the image sensor (which has a focal length f), im Image formation occurs at a distance d from the focal plane. fp At that time, the matrix M describes the corresponding image sensor. cam It is described by the following equation (26):

[0462]

[0463] To find the point where the light ray strikes the focal plane, fp, we can use matrix multiplication as described by equation (27) as follows:

[0464]

[0465] like Figure 38 As shown, the diameter D of the blurred circle blur , is shown as Figure 38 The approximate distance between the two points shown is calculated by measuring the distance from the lens d along the optical axis. im The distant point is found by tracing the rays from the edge of the lens to the focal plane. These rays are given by the vectors shown in (28) as follows:

[0466]

[0467] like Figure 39 As shown, a blurred circle, D blur , are calculated and shown for various lens-to-focal-plane spacings and lens-to-image spacings. In Figure 39 The text also shows contour lines. Figure 77 The x-axis, in micrometers, shows the distance between the focal plane and a point positioned one focal length away from the lens of the image sensor. The y-axis, in meters, shows the distance between the lens and the point where the image was formed. Contour lines are created. Figure 77 The value is the blur size divided by the pixel size; therefore, any value of approximately 1 or less is sufficient for imaging. Figure 39 As shown, the focal plane is located one focal length plus 5 micrometers away from the lens.

[0468] An image sensor can utilize a second lens. For example, an image sensor can utilize a second lens to create a relatively greater depth of field and a relatively larger field of view. Using the same analysis as above (but with the optical matrix modified to accommodate the second lens and additional distance), the depth of field utilizing both lenses can be calculated, as shown in equation (29) below:

[0469]

[0470] Figure 40 and Figure 41 The field of view changes with the distance between the lens and the image sensor, and correspondingly with the focal length of the image sensor. Figure 40 and Figure 41 This shows a blurred circle divided by the pixel size. Figure 40 This shows the blurred circle when using a 20mm focal length lens, divided by the pixel size. Figure 41 This shows the blurred circle when using a 40mm focal length lens, divided by the pixel size. Figure 42 The expression in the middle shows about Figure 40 and Figure 41 The field of view corresponding to the optical axis at the corners of the two configurations.

[0471] like Figure 42 As shown, in some embodiments, the image sensor may utilize a 40mm to 60mm focal length lens; this configuration may include placing the image sensor approximately 2 inches from the focal point. In other embodiments of this disclosure, other configurations may be used, including those not shown in the image sensor. Figure 42 The configurations shown in the image.

[0472] For example, the following analysis shows how depth of field can be set for an image sensor using the lens's focal length, f, distance from the focal plane, z, and distance from a point in space, d; the system's matrix is ​​shown in the following equation (30):

[0473]

[0474] Equation (30) simplifies to the following equation (31):

[0475]

[0476] Equation (31) simplifies to the following equation (32):

[0477]

[0478] Considering points on the axis, all heights will be zero. The points on the focal plane that different rays will strike are given by equation (33) as follows:

[0479]

[0480] As shown in (33) above, θ is the angle of the light ray. The point in perfect focus is given by the lens maker's equation in equation (34) as follows:

[0481]

[0482] Equation (34) can be rearranged to derive equation (35) as follows:

[0483]

[0484] Inserting d from equation (35) into equation (33) yields the following result for the impact point in equation (36):

[0485]

[0486] All light rays leaving that point strike the focal plane at the optical axis. As shown in equation (37), the case where the image sensor is shifted a certain distance δ from the focal point is described as follows:

[0487]

[0488] Equation (37) shows that by properly positioning the lens of the image sensor relative to the focal plane, we can change the depth of field. Furthermore, the spot size depends on the magnitude of the angle θ. This angle depends linearly on the aperture of the vision system generated by the image sensor.

[0489] Additionally or alternatively, according to some embodiments of this disclosure, the image sensor can be implemented by adjusting various parameters, including: the distance to the focal point, as it affects compactness, alignment, and the sensitivity of the vision system to the environment; the system's field of view; and the lens focal plane spacing, as it affects the system's alignment tolerance and the system's sensitivity to the environment.

[0490] Examples of flow meters with or without valves connected to them

[0491] Referring to the attached diagram, Figure 43 and Figure 44 A flow meter 58 coupled to a drip chamber 59 is shown. As described below, the flow meter 58 may optionally include a free-flow detector component 12 according to an embodiment of this disclosure (see [link to relevant documentation]). Figure 1 Additionally, alternatively or optionally, flow meter 58 may include flow estimator component 13 according to some embodiments of this disclosure (see also...). Figure 1 ). Figure 43 A flow meter 58 with a closed door 62 is shown, and Figure 44 A flow meter 58 with an open door 62 is shown. The flow meter 58 can be... Figure 1 The flow meter 7 may have a valve 6 or not. The flow meter 58 includes an start knob 60 and a stop knob 61. Alternatively or additionally, the flow meter 58 may include a backup valve to stop the fluid flowing through it, or may signal another valve to stop the fluid flow in response to an error condition.

[0492] Flow meter 58 optionally includes image sensors 63 and 64 capable of estimating fluid flow and / or detecting free-flow conditions. While flow meter 58 includes two image sensors (e.g., 63 and 64), only one of image sensors 63 and 64 may be used in some embodiments. When a droplet forms within the drip chamber 59, image sensors 63 and 64 are capable of imaging the droplet and estimating its size. The droplet size can be used to estimate the fluid flow through the drip chamber 59. For example, in some embodiments of this disclosure, image sensors 63 and 64 use an edge detection algorithm to estimate the contour of the droplet size formed within the drip chamber 59; wherein the processor (see...) Figure 1 Processor 15, Figure 5 The processor 75, or Figure 6 A processor (or an 8-bit processor) can assume that the profile is uniform from every angle of the droplet and can estimate the droplet size based on the profile. Figure 43 and Figure 44 In the exemplary embodiment shown, the two image sensors 63 and 64 can average the two profiles together to estimate the droplet size. For example, the algorithm can calculate the average of the measured profiles from the two image sensors 63 and 64 to determine the droplet size. Image sensors 63 and 64 can use a reference background pattern to facilitate the identification of the droplet size as described herein.

[0493] In another embodiment of this disclosure, image sensors 63 and 64 image the fluid to determine if free-flow conditions are present. Image sensors 63 and 64 can use a background pattern to determine whether the fluid is flowing freely (i.e., droplets are not forming and fluid is flowing through the drip chamber 59). As previously mentioned, although the flow meter 58 includes two image sensors (e.g., 63 and 64), only one of image sensors 64 and 64 may be used in some embodiments to determine if free-flow conditions are present and / or to estimate the flow of fluid through the drip chamber.

[0494] Additionally or alternatively, in some embodiments of this disclosure, another image sensor 65 monitors the fluid tube 66 to detect the presence of one or more bubbles within the fluid tube. In alternative embodiments, other bubble detectors may be used instead of the image sensor 65. In other embodiments, bubble detection is not used in the flow meter 58.

[0495] Now refer to the attached diagram, Figure 45 A flow meter 218 is shown coupled to a drip chamber 219 according to an embodiment of the present disclosure. The drip chamber 219 is fixed to the flow meter 218 via a coupler 410. Backlight 220 illuminates light through the drip chamber toward an image sensor 221 (shown in outline).

[0496] Flow meter 218 can electronically transmit flow to monitoring client 8 (see Figure 1 Additionally or alternatively, in some optional embodiments, flow meter 218 may include a display for showing flow rate (e.g., a touchscreen, LED display, etc.). Flow meter 218 may be coupled to rod 223 via clamp 222.

[0497] In some embodiments, the flow meter 218 can be coupled to an actuator (which is coupled to a valve) (in Figure 45 (not shown in the image) to form a closed-loop system (e.g., Figure 1 The control unit 14, such as a PID, switch, neural network, or fuzzy logic control system, is used to regulate the flow of fluid through the drip chamber 219.

[0498] Flow meter 218 can use any flow algorithm described herein and may include any imaging system described herein. Additionally or alternatively, flow meter 218 may include a free-flow detector component (e.g., Figure 1 (Free-flow detector component 12).

[0499] Figure 46 A flow meter 224 according to an embodiment of the present disclosure and a pinch valve 225 coupled to a body 226 of the flow meter 224 to control the flow of fluid into a patient's body are shown. The flow meter 224 includes an image sensor 227 and a backlight 228.

[0500] Image sensor 227 images the drip chamber 229 and is able to receive illumination from backlight 228. Flow meter 224 includes a support member 230 coupled to coupler 231, which couples the drip chamber 229 to the flow meter 224.

[0501] Flow meter 224 can implement any flow estimator described herein (e.g., Figure 1 The flow estimator component 13) and / or the free-flow detector disclosed herein (e.g., Figure 1 The free-flow detector component 12). The flow meter 224 can use a pinch valve 225 in closed-loop form to control the flow of fluid to the patient (e.g., using a free-flow detector component 12). Figure 1 The control component 14 shown.

[0502] Pinch valve 225, if in Figure 47 As can be more easily seen in the diagram, it is coupled to shaft 233, which is coupled to actuator 234. Actuator 234 can be a solenoid or any actuator capable of moving clamp valve 225 toward tube 335.

[0503] Figure 48 A flow meter 336 and a pinch valve 225 according to an embodiment of the present disclosure are shown. The flow meter includes two image sensors 337 and 338. The flow meter 336 can use the pinch valve 225 in a closed-loop feedback configuration. The flow meter 336 can use the image sensors 337 and 338 to implement the volume estimation algorithm described herein to estimate the flow of fluid through the drip chamber 229. For example, the flow meter 336 can average the two volumes together for use in the feedback loop.

[0504] Figure 49 The diagram shows a flow meter 339 and a valve 340 coupled to an actuator 341 to control the flow of fluid into a patient, according to an embodiment of the present disclosure. Figure 49 The flow meter 339 is similar to Figure 46 The flow meter is 224; however, Figure 49 The flow meter 339 includes a valve 340 having curved, elongated support members 342 and 343 (see...). Figures 50A-50B ).

[0505] The flow meter 339 includes an image sensor 227 and a backlight 228. The image sensor 227 images the drip chamber 229 and is able to receive illumination from the backlight 228. The flow meter 339 includes a support member 230 coupled to a coupler 231, which couples the drip chamber 229 to the flow meter 339.

[0506] Flow meter 339 can implement any flow estimator described herein (e.g., Figure 1The flow estimator component 13) and / or the free-flow detector disclosed herein (e.g., Figure 1 The free-flow detector component 12). The flow meter 339 can use a valve 340 in a closed-loop form to control the flow of fluid into the patient's body (e.g., using a free-flow detector component 12). Figure 1 Control component 14).

[0507] The flow meter 339 can actuate the actuator 341 to actuate the valve 340, which in turn uses an arbitrary control algorithm to regulate the fluid flowing through the IV tube 335 in a feedback (i.e., closed-loop) configuration.

[0508] Now refer to Figures 50A-50B It illustrates embodiments according to this disclosure. Figure 49 A close-up view of valve 340. Valve 340 includes an inner curved elongated support member 343 and an outer curved elongated support member 342. A tube 335 is positioned between support members 342 and 343.

[0509] The inner support member 343 includes a cylindrical nut 344. The outer support member 342 is coupled to the cylindrical nut 344 via a hook 345. In some embodiments, the cylindrical nut 344 is not coupled to the valve 340, and the inner support member 342 includes a hole through which a threaded rod or screw 347 slides. The outer support member 342 also has a hook 348 to secure it to a frame 349 of the actuator 341. The actuator 341 includes a shaft 346 coupled to the screw 347. As the actuator 341 rotates the shaft 346, the screw 347 is able to rotate to push the cylindrical nut 334 toward the actuator 341. That is, the hook 345 and the cylindrical nut 334 move toward the hook 348 and the frame 349 because the inner and outer support members 342 and 343 are flexible.

[0510] As support members 342 and 343 are compressed, pipe 335 becomes compressed because it is positioned between support members 342 and 343. The compressed pipe 335 restricts the flow of fluid through it. Valve 340 compresses pipe 335 by a length approximately greater than the diameter of pipe 335.

[0511] Figures 51A-51D Several views of a flow meter 350 having a monitoring client 358, a valve 352, a drip chamber 357, an IV bag 411, and a fluid line 412 according to an embodiment of the present disclosure are shown. The flow meter 350 includes a reception portion 351 for receiving the valve 352. The valve 352 includes two curved elongated support members 353 and 354.

[0512] The flow meter 350 includes an image sensor 355 and a backlight 356 capable of monitoring droplets formed within the drip chamber 357. The flow meter 350 can use the image sensor 355 to implement the flow estimator algorithm described herein (e.g., Figure 1The flow estimator component 13) and / or implements the free-flow detector disclosed herein (e.g., Figure 1 (Free-flow detector component 12).

[0513] The flow meter 350 includes a base 359 that can form a dock to receive a monitoring client 358. The monitoring client 358 can be a smartphone or other electronic computing device (e.g., an Android-based device, iPhone, tablet, PDA, etc.).

[0514] The monitoring client 358 may include software to implement free-flow detectors, flow estimators, control components, exposure components, etc. (e.g., Figure 1 The flow meter 350 may include a free-flow detector component 12, a flow estimator component 13, a control component 14, and an exposure component 29, and may also include one or more transceivers (e.g., transceiver 9). Alternatively or additionally, the base 359 of the flow meter 350 may implement these features.

[0515] For example, flow meter 350 can use internal software, hardware, and electronic devices to implement free-flow detectors, flow estimators, control components, and exposure components. Flow meter 350 can implement a closed-loop feedback system to regulate the flow to the patient by changing the fluid flowing through valve 352.

[0516] As in Figure 51B As can be easily seen, valve 352 includes an inner support member 354 and an outer support member 353. The inner support member 354 is coupled to a cylindrical nut 360 and to a cylinder 361. In some embodiments, the cylindrical nut 360 is not coupled to the inner support member 354, and the inner support member 354 includes a hole for allowing the threaded shaft 362 to slide through.

[0517] A threaded shaft 362 (e.g., a screw) rotates freely within a bearing located within a cylinder 361 and engages a threaded nut within a cylindrical nut 360 by rotation of a knob 363 to push or pull the cylindrical nut 360 relative to the cylinder 361 (e.g., the actuator is a lead screw with a knob to actuate the lead screw). The knob 363 can be rotated manually.

[0518] Alternatively, valve 352 may engage with a receiving portion 351 including a rotating member 364, the rotating member 364 engaging with a knob 363 within the receiving portion 351 (see also...). Figure 51C Rotating member 364 engages rotating knob 363 to actuate valve 352. Rotating member 364 may be coupled to an electric motor that rotates rotating member 364. The electric motor (not explicitly shown) may be controlled by a flow meter 350 configured in a closed loop to achieve a target flow rate of fluid flowing into the patient's body.

[0519] Figures 52A-52D Several views of another flow meter 365 having a valve 352, a drip chamber 357, and a fluid conduit 413 according to an embodiment of the present disclosure are shown. The fluid conduit 413 has a receiving portion 351 to receive the valve 352. Figures 52A-52D The flow meter 365 is similar to Figures 51A-51D The flow meter 350; however, the base 359 holds the monitoring client 358 in a "vertical" position. Additionally, the receiving part 351 is located on the side of the base 359 opposite to the monitoring client 358 (see...). Figure 52B and 52C ).

[0520] Figure 52D A close-up view of the valve 352 engaging with the receiving portion 351 is shown. The knob 363 engages with a rotating member inside the base 359. Figure 52D (Not shown in the image), base 359 is coupled to motor (in...) Figure 52D (Also not shown).

[0521] Figure 53A Show Figures 51A-51D and Figures 52A-52D Another view of valve 352, and Figure 53B-53C Embodiments according to this disclosure are shown Figure 53A Two exploded views of the valve.

[0522] like Figures 53A-53C As shown, valve 352 includes an inner support member 354 and an outer support member 353. A pipe can be inserted into through holes 366 and 367 to position the pipe between support members 354 and 353.

[0523] The knob 363 can be rotated to rotate the screw 362. The rotation of the screw 362 causes the cylindrical nut 360 to move toward the partial cylinder 363 to compress the tube positioned between the support members 353 and 354. However, the partial cylinder 363 includes two sides, with spaces existing to securely hold the end 600 of the screw 362 (e.g., a cap) within these spaces (e.g., an auxiliary space). Figure 54 Valve 352 is shown for manual use and is coupled to pipe 368.

[0524] Figure 55 A valve 369 comprising two flexible members 370 and 371 is shown according to an embodiment of the present disclosure. Flexible members 370 and 371 may be two flexible sheets. Flexible member 371 may include orifices 373 and 374 for positioning a tube 372 between the flexible members 370 and 371.

[0525] Flexible members 370 and 371 are coupled together via two connector members 377 and 378. Connector members 377 and 378 are coupled to coupling members 376 and 375, respectively.

[0526] Actuation of valve 369 can be achieved by a linear actuator that pulls coupling members 377 and 378 toward or away from each other. The linear actuator (not explicitly shown) can be a screw-type actuator, a piston actuator, or other actuator. In some embodiments, one of coupling members 375 and 376 may be coupled to a fixed support, while the actuator is coupled to another of coupling members 375 and 376 and another fixed support to bring coupling members 375 and 376 together or apart.

[0527] Figures 56A-56C Several views of a valve 380 having two curved elongated support members 381 and 382 according to an embodiment of the present disclosure are shown, and one of the elongated support members 381 has a plurality of ridges 387 adapted to engage a pipe positioned between the support members 381 and 382.

[0528] Valve 380 has two support members 381 and 382 coupled to a coupling member 383 at a first end and to a second coupling member 384 at the other end. That is, the coupling member 384 surrounding the screw 385 and the coupling member 383 includes an internal thread that is used to pull the coupling member 383 toward or away from the knob 386 when the screw 385 rotates with the knob 386. Figure 56B A valve 380 is shown, which, when actuated, is used to close off fluid flowing through a pipe coupled between support members 381 and 382. Figure 56C A support member 381 with two holes 388 and 389 for receiving a tube is shown. It is also noted that support members 381 and 382 hold the tube eccentrically from the axis of the screw 385, which... Figure 56C It is easy to see in the middle. The retaining tube is eccentric from the axis of screw 385 to promote the free movement of the tube.

[0529] Figures 57A-57C Several views of a valve 390 having a ratchet 394 according to an embodiment of the present disclosure are shown. The ratchet 394 engages the connecting member 393 of the valve 390, and... Figure 57D-57E Show Figures 57A-57C Two exploded views of valve 390. Racket 394 engages connecting member 393 by interacting with rack 397 arranged thereon. Finger 602 (see...) Figure 57D and 57EThe ratchet 394 interacts with the rack 397 to provide a ratcheting action. That is, the finger 602 can hold the rack 397 against an engaging finger on the side opposite to the holding finger 602. The valve 390 includes a support member 391 having one end coupled to the ratchet 394 and the other end pivotally coupled to the hinge 395. The valve 390 also includes a support member 392 having a hook 398 capable of coupling to the body of the ratchet 394.

[0530] like Figure 57C As shown, tube 396 can be positioned between support members 391 and 392, hook 398 can be fastened to the body of ratchet 394, and connecting member 393 can be inserted into ratchet 394 (e.g., Figure 57B As shown). Figure 57C As shown, pipe 396 is positioned to abut against support member 391 via openings 399 and 400.

[0531] The ratchet 394 engages the rack 397, allowing manual movement of the ratchet 394 toward the hinge 395 for fluid flow adjustment. A knob (not shown) can then be coupled to the ratchet 394 to make minor adjustments to the distance between the ratchet 394 and the hinge 395. Alternatively, the ratchet 394 may include a release knob (not shown) for releasing the ratchet from the connecting member 393.

[0532] Figures 58A-58D Several views of a valve 401 having two elongated support members 403 and 404, a connecting member 405, and a helical actuator 407 according to another embodiment of the present disclosure are shown.

[0533] Support members 403 and 404 may be permanently molded together at their ends with the end of connecting member 405. Pipe 402 may be positioned between support members 403 and 404.

[0534] As the knob 408 is rotated, the helical actuator 407 extends or retracts due to its engagement with the threaded rod 406. Figure 58A The valve is shown in the open position, while Figure 58B The valve is shown in the closed position. Note that pipe 402 is compressed along its approximate length. Figure 58C-58D Valve 401 is shown in the open and closed positions from a perspective view.

[0535] Figures 59A-59C Several views of the body 501 of the valve 500 according to an embodiment of the present disclosure are shown (see also: Regarding the assembly of the valve 500, see...). Figure 59HThe main body 501 includes a first curved elongated support member 502 and a second curved elongated support member 503. The first support member 502 includes protruding holes 504 and 505 for holding the tube between the support members 502 and 503.

[0536] The main body 501 also includes a first connector 506 coupled to one end of the support members 503 and 504 and a second connector 507 coupled to the other end of the support members 503 and 504.

[0537] The first connector 506 is coupled to one end of the support members 503 and 504 and connected to the first end 508 of the connecting member 509. The second connector 507 includes a hole 510 for positioning the second end 511 of the connector member 509 through it (as shown in...). Figure 59B (Easily visible in the middle).

[0538] When the tube is positioned between support members 502 and 503, the movement of the second connector 507 toward the first connector 506 compresses the tube disposed between the support members 502 and 503. As the second connector 507 moves toward the first connector, the hole 510 of the second connector 507 allows the second end 511 of the connector member 509 to slide freely therein.

[0539] Figure 59D-59G This illustration shows an embodiment of the present disclosure for use with Figures 59A-59C Several views of a knob 512 used in conjunction with the body 501 shown. The knob 512 includes a ratchet 513 defined by four fingers 514. Each of the fingers 514 includes a threaded surface 515 for engaging a threaded connecting member 509. The fingers 514 are arcuate toward a hole 516 at the center of the knob 512. The knob 512 also includes a finger 517 engaging a second connector 507 (see...). Figure 59H In some embodiments, the body 501 includes a recess 510 to receive a finger 517 on the second connector 508.

[0540] Figure 59H An assembly valve 500 according to an embodiment of the present disclosure is shown, the assembly valve 500 including Figures 59A-59C The coupling shown is to Figure 59D-59GThe body 501 of the knob 512. The knob 512 slides onto the thread of the connecting member 509. The finger-shaped members 514 engage the thread of the connecting member 509 and are strangled to the connecting member 509. That is, the knob 512 can move freely toward the first end 508 of the connecting member 509 along the thread of the connecting member 509, but the knob 512 cannot be removed from the first end 508 of the connecting member 509 without rotating the knob 512. That is, the knob 512 can be placed on the connecting member 509 to provide coarse adjustment of the valve 500 by coarsely moving the connectors 507, 508 toward each other to close the valve 500. Because the threaded surfaces 515 of the four finger-shaped members 514 engage the thread of the connecting member 509, rotation of the knob 512 reduces or increases the fluid flow in the pipe. Each of the finger members 514 includes a threaded surface 515 to engage the threads of the connecting member 509, such that rotation of the knob 512 causes the second connector 507 to move toward or away from the first connector 506 to thus control the flow of fluid in the tube positioned between the support members 502, 503.

[0541] Figure 60 A valve 520 with a guide protrusion 521 is shown according to an embodiment of the present disclosure. The valve 520 is similar to... Figure 59H The valve 500 includes a guide protrusion 521 and a knob 522 having first and second retaining rings 523, 524. The knob 522 also includes an internal thread (not shown) for engaging a thread 525 of a connecting rod 526. In some embodiments, the internal thread may be engaged, and in other embodiments, the internal thread may be fixed and not provide engagement.

[0542] Figure 61 An embodiment of the present disclosure is shown for coupling to Figure 60 The valve 520 includes a motor 536 and a valve fixing structure 537. The valve fixing structure 537 includes fixing fingers 528, 529, 530, and 531, each of which has a bent portion 533 for attaching to the retaining rings 523 and 524 of the knob 522 (see...). Figure 62 It is snapped into the corresponding guide ring 534.

[0543] Now refer to Figure 60 , 61 Once retaining rings 523 and 524 are fully secured, knob 522 rotates freely. That is, retaining ring 523 can be secured between retaining fingers 528 and 530 within their respective retaining ring guide portions 534, allowing knob 522 to rotate. Similarly, retaining ring 524 can be secured between retaining fingers 529 and 531 within their respective retaining ring guide portions 534, allowing knob 522 to rotate.

[0544] When valve 520 is secured to valve mounting structure 537, the rotation of wheel 537 (caused by motor 536) causes knob 522 of valve 520 to rotate. As valve 520 bends, protrusion 521 moves freely within or adjacent to protrusion guide 535. Figure 62 Show Figure 60 The valve is fastened to the motor 536 via the valve fixing structure 537.

[0545] Figure 63 An embodiment of the present disclosure is shown for coupling to Figure 60 The valve also includes another motor 538 and a valve mounting structure 539. The valve mounting structure 539 includes a protruding guide 540 adjacent to the motor 538. The motor 538 is coupled to a wheel 541 to engage a knob 522 (see [link]). Figure 60 ).

[0546] Figure 64A A valve 542, according to an embodiment of the present disclosure, is shown having a sliding retainer 545 for regulating fluid flow through a fluid line 543 and a plurality of compression fingers 544. A base 546 is connected to all the fingers 544. As the sliding retainer 545 moves on the compression fingers 544, the compression fingers 544 compress the tube 543 to impede fluid flow therein. Figure 64B Show Figure 64A A cross-sectional view of the valve.

[0547] Figure 64A A valve 542 according to an embodiment of the present disclosure is shown, having a slidable retaining ring 545 for regulating fluid flow through a fluid line 543 and a plurality of fingers 544. The fingers 544 are coupled to a base 546 such that the base 546 and the fingers 544 surround a tube 543. The retaining ring 545 is slidable away from the base 546 such that the fingers 544 compress the tube 543, thereby reducing the internal volume of the tube 543. The reduction in the internal volume of the tube 543 reduces the fluid flow through the tube. An actuator (not shown) may be coupled to the retaining ring 545 to control the position of the retaining ring 545 (e.g., a linear actuator may be coupled to the retaining ring 545 and to the base 546). Figure 64B Show Figure 64A A cross-sectional view of valve 542. Note that finger 544 can be shaped to be opposite the end of the tube near the base.

[0548] Figure 65A valve 547 according to an embodiment of the present disclosure is shown, the valve 547 having two curved surfaces 549 and 550 for positioning a fluid conduit 548 between them to regulate the flow of fluid through the fluid conduit 548. As the surfaces are compressed together, the conduit 548 between them is compressed. The two curved surfaces 549 and 550 can be compressed together using an actuator. The conduit 548 can be wrapped around the surface 549 several times.

[0549] Figure 66A-66G Several views of a valve 551 having a knob 552 according to an embodiment of the present disclosure are shown. After the knob 552 is moved, the knob 552 moves the locking connection member 553.

[0550] Valve 551 includes an inner curved elongated support member 554 and an outer curved elongated support member 556. Knob 552 is pivotally coupled to the outer support member 556 via a pin 578. Connecting member 553 engages the teeth 576 of knob 552.

[0551] The connecting member 553 can be inserted into the hole at the end 555 of the support member 556, such that rotation of the knob 552 will engage the finger member 700 (see...). Figure 66D The knob 552 is frictionally locked into the rack 558 of the connecting member 553. The engaging finger 700 can engage the teeth 576 to lock the knob 552, thus preventing the knob 552 from rotating unless sufficient torque overcomes the locking action of the engaging finger 700. The finger 577 is positioned on the other side of the hole 571, pressing against the teeth 576 of the knob 552 to compress the connecting member 552.

[0552] The inner support member 554 can pivot out from the outer support member 556, allowing the tube to be loaded via protrusions 559 and 560 (see...). Figure 66C The inner support member 554 pivots out from the outer support member 556 via dog-bone shapes 561, 562, 701, and 702, as shown. Figure 66C As shown. Then, the inner support member 554 pivots back towards the support member 556, as... Figure 66D As shown. Then, the connecting member 553 is inserted into the end 555 of the outer support member 556 (in Figure 66E (A close-up view of the insertion is shown in the image). The outer support member 556 includes an engaging finger 700 that locks into the teeth 576 of the knob 552, which temporarily secures the connecting member 553 (see [reference]). Figure 66GThe other end 581 of the connecting member 553 is locked in a hole 582 in the end 557 of the support member 556. The connecting member 553 can be pivotally connected to the end 557. The knob 552 includes teeth 576 to move the connecting member 553 into or out of the end 555. However, when the knob 552 is not moving, the engaging finger 700 locks the movement of the knob 552 unless a predetermined amount of torque strikes the finger 700 against the next tooth of the tooth 576 inside the knob 552.

[0553] As previously mentioned, support member 554 can swing away from outer support member 556, such as Figure 66C As shown, dog-bone links 561, 562, 701, and 702 facilitate this action. Dog-bone link 561 includes a pivot hole 572 coupled to pivot 563 and a pivot hole 573 coupled to pivot 565. Dog-bone link 562 includes a pivot hole 575 coupled to pivot 566 and a pivot hole 574 coupled to pivot 566. Dog-bone link 701 is coupled to pivots 567 and 570, and dog-bone link 702 is coupled to pivots 568 and 569, causing the end of support member 556 to also swing away from inner support member 554.

[0554] Figure 67 A diagram 408 illustrating the actuation of a valve relative to its flow rate according to an embodiment of the present disclosure is shown. Diagram 408 illustrates the operation of a valve having an elongated support member, such as, for example, Figure 49 and Figures 50A-50B Valve 340, Figure 51A-54 Valve 352, Figure 55 Valve 369, Figures 56A-56C Valve 380, Figures 57A-57E Valve 380, Figures 58A-58D Valve 401, Figure 59H Valve 500, Figure 60-60 Valve 520, Figures 64A-64B Valve 542, Figure 65 Valve 547, and / or Figure 66A-66G Valve 551. The x-axis of diagram 408 shows the displacement between the two ends of the valve's support member, and the y-axis shows the flow rate (e.g., caused by gravity and / or pressure sources). The valve's response is a non-linear function, such as an S-curve, an S-shaped curve, a Gompertz curve, or a generalized logistic function. These functions can be adjusted to match the valve, and / or the valve can be adjusted to match one of the curves or functions.

[0555] Figure 68AA flow meter 703 using a binary optical element 705 is illustrated according to an embodiment of the present disclosure. The flow meter 703 includes a camera 355 that captures one or more images to estimate the flow rate of fluid through a drip cavity 357 using any suitable method (e.g., the methods disclosed herein). The flow meter 703 includes a laser 704 that directs a laser beam onto the binary optical element 705. The binary optical element 705 then redirects and reassembles the laser beam through the drip cavity 357 onto an image sensor 355, such that the image sensor 355 sees a pattern, e.g., Figure 8 The linear array 85 shown can be formed as shown in Figure 10 The stripes shown in the background pattern 89. The binary optical component 705 can form stripes by using multiple ellipses.

[0556] Image sensor 355 may include filters to filter out all frequencies other than the frequency of laser 704. For example, image sensor 355 may include an optical bandpass filter having a center frequency equal to (or approximately equal to) the optical frequency (or the center frequency of the optical frequency) of laser 704.

[0557] The monitoring client 358 can be electrically coupled to the laser 801 to modulate the laser 801. For example, the monitoring client 358 can turn on the laser 801 only when a predetermined pixel is exposed, and turn off the laser 801 when other pixels besides the predetermined pixel are exposed.

[0558] The flow meter 703 optionally includes a first electrode 800 and a second electrode 801. A monitoring client 358 can be electrically coupled to the first and second electrodes 800, 801 to measure the capacitance defined between them. Under fluidization conditions, the capacitance changes because the relative permittivity differs for air and water. By monitoring the capacitance between the first and second electrodes 800, 801, the monitoring client 358 can monitor changes in fluidization conditions arising within the drip chamber 357 and correlate increases and / or decreases in capacitance exceeding a threshold with corresponding fluidization and / or non-fluidization conditions. For example, if the capacitance between the first and second electrodes 800, 801 is above a threshold, a processor within the monitoring client 358 can determine that the drip chamber 357 is experiencing fluidization conditions.

[0559] In an alternative embodiment, the first and second electrodes 800, 801 are loop antennas. The monitoring client 358 uses a transceiver to monitor the magnetic coupling between the loop antennas 800, 801. For example, the transceiver can transmit coded information from one loop antenna of the 800, 801 to the other loop antenna of the 800, 801 and then determine whether the coded information was successfully received. If so, a received signal strength indication (“RSSI”) measurement can be performed from the transceiver. The RSSI can be used to monitor the magnetic coupling between the antennas 800, 801. If the magnetic coupling is above a threshold, the monitoring client 358 can determine that fluidization conditions exist within the drip chamber 357. In some embodiments, a change in magnetic coupling or a change in capacitive coupling can be determined as an indication that fluidization conditions have occurred.

[0560] The flow meter 703 may also include a safety valve 706. Figures 69A-69F Several views of a safety valve 706, which can be used with a flow meter (such as flow meter 703 of FIG. 68), are shown according to embodiments of the present disclosure.

[0561] Figures 69A-69B An exploded view of safety valve 706 is shown. Safety valve 706 includes a solenoid 707, an interface structure 708, a housing 709, a spring 720, a panel 712, a first shaft 713, a second shaft 714, a first sealing arm 710, and a second sealing arm 711. Panel 712 includes a hole 715, and housing 708 also includes a hole 819. Holes 715 and 819 allow shaft 713 to slide within holes 715 and 819.

[0562] like Figure 69C As shown, tube 820 can be placed inside tube housing 709. Tube 820 is positioned close to... Figure 69D The first and second sealing arms 710 and 711 are easily visible in the image. When in the retracted state (e.g.) Figure 69D (As shown), spring 720 holds the first and second blocking arms 710, 711 retracted, but stores energy, causing a predetermined amount of movement of the first and second blocking arms 710, 711 toward tube 810. This causes the spring to release its stored mechanical energy, causing the first and second blocking arms 710, 711 to extend and block tube 820. Spring 720 may be a compression spring 720, which can pull 713 and 714 toward each other. The first and second blocking arms 710, 711 may be pivotally connected together. As shown in Figure 69E As can be easily seen, the shaft 718 of the solenoid 707 can be actuated through the hole 719 in the tube to push on the spring 720, which causes the spring 720 to release its energy and seal the tube 820 (for the case where the first and second sealing arms 710, 711 are in the sealing position, see...). Figure 69F ).

[0563] Figure 70 A flowchart illustrating a method 728 for estimating droplet growth and / or flow within a drip chamber according to embodiments of the present disclosure is shown. Method 728 includes actions 729-735. Figures 71A-71B Images captured by a flow meter with a template stacked therein are shown to illustrate this. Figure 70 The method.

[0564] Action 729 captures an image of the infusion chamber. Image capture can be... Figure 71A Image 721. Action 730 positions the template within the captured image to a first position. For example, as... Figure 71A As shown, template 727 can be positioned within a predetermined location. Action 731 averages all pixels within template 727. Action 732 moves the template to a second position. For example, Figure 71A Template 727 in the template can move the template along the Y direction (e.g., in...). Figure 71A (See the downward movement in the middle).

[0565] In action 733, pixels within the template are used to determine a second average value. In action 734, if the difference between the second average value and the first average value is greater than a predetermined threshold, it is determined that the template is positioned at the edge of the droplet. For example, refer to... Figure 71A The template can be slowly lowered along the Y direction until template 727 transitions from the edge of the droplet to a portion of the image that does not contain the droplet. In this case, the average pixel value will abruptly transition from a darker average value to a lighter average value. When this transition occurs, the Y position of template 727 is considered to be at the edge of the droplet (e.g., Figure 71A The second position of the droplet is associated with its volume in action 735. For example, the Y1 value may be associated with the volume of the droplet in a lookup table. In some embodiments of this disclosure, multiple movements of the template 727 are required until the edge of the droplet is detected. For example, the template 727 may move one pixel at a time (or several pixels at a time) along the y-direction, and several movements of the template 727 may be required to detect the edge of the droplet. By monitoring the edge of the droplet, the growth of the droplet can be controlled by a flow meter to achieve a target flow rate (e.g., a PID control loop within the flow meter can control the flow rate). Figure 71A Y1 to Figure 71B (the rate of transition between Y2). Figure 71B Showing relative Figure 71A The position Y1 corresponds to the position Y2, which is the growth in the droplet.

[0566] Figure 72 A modular backlight assembly 740 according to an embodiment of the present disclosure is shown. Assembly 740 may be... Figure 1The backlight 18 may be used as the backlight for any suitable flow meter disclosed herein. Component 740 includes a first circuit board 738, a second circuit board 739, a first backlight diffuser 736, and a second backlight diffuser 737.

[0567] The first circuit board 738 includes an embedded light source 822 extending along the interface between the first backlight diffuser 736 and the first circuit board 738. The embedded light source 822 illuminates the first backlight diffuser 736, and the light is directed outwards, as indicated by 821. The light 821 can be directed toward an image sensor. When viewed through the image sensor, the first backlight diffuser 736 only diffuses light without forming a "pattern".

[0568] The second circuit board 739 includes an embedded lamp 823 that illuminates a second backlight diffuser 737. When viewed through an image sensor, the second backlight diffuser 737 produces a striped pattern indicated by light 821. Therefore, monitoring clients (e.g., Figure 51A The monitoring client 358) and / or flow meter (e.g., Figure 1 The flow meter 7) can be selected between a striped background pattern (by activating the embedded light 823) and a non-striped background pattern (by activating the embedded light 822).

[0569] For example, now refer to Figure 1 and Figure 72 In some specific embodiments, the flow meter 7 may use a backlight assembly 740; the flow meter 7 may use a non-striped backlight pattern (by activating the embedded LED 822 and not activating the embedded LED 823) to monitor droplet growth and may switch to a striped background pattern (by activating the embedded LED 823 and not activating the embedded LED 822) to detect fluidization conditions.

[0570] Figures 73A-73C Several views of a tube restoration device 741 according to an embodiment of the present disclosure are shown. The device 741 includes a drive gear 744 coupled to a first restoration gear 742. The first restoration gear 742 is mechanically coupled to a second restoration gear 743. A tube can be placed between the first and second restoration gears 742, 743. A portion of the first and second restoration gears 742, 743 defines a space 745 in which the tube can be positioned. The distance between the rotational enclosed spaces 745 of the first and second restoration gears 742, 743 when the tube is positioned between them is also shown. Figures 73B to 73C This illustrates the transition from the non-recovery position to the recovery position. For example, the tube can be positioned such that the sealing element presses against the tube from bottom to top (e.g., Figure 73B(As shown). If the tube becomes twisted over time, the motor connected to drive gear 744 rotates gears 743 and 744 to press against the tube wall (as shown). Figure 73C (As shown) the tube is restored to an approximate cross-section by compressing the wall portion of the tube that extends beyond the central axis of the tube, causing the tube to twist into, for example, an elliptical shape.

[0571] Figure 74 A system is shown for regulating fluid flow 746 using a valve 747 with two flexible strips 753 and 754 (see [link]). Figure 75 );and Figure 75 Embodiments according to this disclosure are shown Figure 74 Valve 746. Optionally, in one embodiment, a motor may be attached to valve 746 for control by a flow meter.

[0572] like Figure 75 As shown, valve 74 includes: two flexible strips 753, 754, between which a tube can be arranged; a guide shaft 752 for guiding members 749, 750; a screw 751; and a knob 748.

[0573] When knob 748 is rotated, screw 751 rotates. The rotation of screw 751 pulls distal guide member 750 toward proximal guide member 749 (because distal guide member 750 includes internal threads, and screw 751 rotates freely within proximal guide member 749). Guide member 751 guides the movement of distal guide member 750. Guide member 751 is coupled to proximal guide member 749.

[0574] Figure 76A A valve 755 utilizing a fluid-based bladder 758 is illustrated according to an embodiment of the present disclosure. The valve 755 includes two shells 756 and 757, a bladder 758, and a piston 759. The piston 759 can be any fluid source. The bladder 758 can be placed within a cavity 764, and a tube can be positioned across the bladder 758 and located within channels 760 and 761. The shell 757 can then be placed on the bladder 758, such that the cavity 765 is placed on the bladder 758. The two shells 756 and 757 can then be ultrasonically welded together, temporarily compressed together, and / or fully held together. An actuator (e.g., an actuator controlled by a flow meter disclosed herein) can then be actuated to allow fluid to flow through the piston 759 into and out of the bladder 758.

[0575] Figure 76B Embodiments according to this disclosure are shown Figure 76A A cross-sectional view of an assembled valve 755 with two resilient packings 1002 and 1004. When the bladder 758 is deflated, the resilient packings 1002 and 1004 help hold the tube 1000 in place and help restore the tube 1000.

[0576] Figure 77 A system 766 is shown according to an embodiment of the present disclosure for regulating fluid flow using a valve 769 having two flexible bars 771, 772 actuated by a linear actuator 822. Figure 78 A linear actuator 822 is shown that actuates valve 769 to impede fluid flow through pipe 775. Valve 769 is coupled to two couplers 767 and 768. Proximal coupler 768 moves with linear actuator 822, while distal coupler 767 is fixed relative to the non-moving end of linear actuator 822.

[0577] Figure 79 Show Figures 77-78 A close-up view of valve 769. Valve 769 includes two strips 771, 772 (which may be metal strips), and tube 775 can be arranged in the two strips 771, 772. The two strips 771, 772 of valve 769 can be coupled to a first end structure 773 and a second end structure 774. The first end structure 773 can be coupled to a distal coupler 767, and the second end structure 774 can be coupled to a proximal coupler 768 (see...). Figures 77-78 Rope 770 or membrane may be wound around tube 775 such that, when strips 771 and 772 are straightened, rope 770 presses against the sidewall of tube 775 to help round tube 775. Membrane may be a flexible but non-stretchable material (or at least a stretchable material). Figure 80 As shown in Figure 78 A close-up view of the valve actuated in the middle. Note that the rope 770 passes through holes 776 and 778 in a threaded manner. The rope 770 (which may be metal) is spirally wrapped around tube 775 so that when valve 769 is opened, rope 770 returns to tube 775.

[0578] Figure 81 The following illustrations are provided to illustrate the estimation method according to embodiments of the present disclosure. Figures 82A-82B Several images illustrating methods of droplet growth and / or fluid flow. Figure 81 Show the following mentioned and Figures 82A-82B Related images 771-777.

[0579] Figures 82A-82B A flowchart illustrating method 803 for estimating droplet growth and / or fluid flow is shown. Method 803 includes actions 804-818.

[0580] Action 804 captures the first image (e.g., Figure 81 Image 771). The first image can be a grayscale image of the droplet converter. The droplet cavity can be uniformly illuminated by a stripe pattern on the bottom of the cavity (i.e., there is no background pattern on the top of the droplet cavity).

[0581] Action 805 uses the first image to generate a first thresholded image. The first thresholded image can be... Figure 81 Image 774. The first thresholded image can be achieved by comparing each pixel of the first image with a threshold (e.g., if the corresponding pixel of the first image is above the threshold, the corresponding pixel of the thresholded image is set to 0, or if the corresponding pixel of the first image is below the threshold, the corresponding pixel of the thresholded image is set to 1). This action highlights the area in front of the background where water exists.

[0582] In some specific embodiments, the threshold level is updated each time a new image is acquired to ensure that a predetermined ratio of 1 to 0 pixels is maintained to highlight the droplet. When used again, the ratio can be updated for use by action 805, or the threshold can be updated to adjust the predetermined ratio of 1 to 0 pixels, and then the first thresholded image is used for the rest of method 803.

[0583] Action 806 determines a pixel group connected to a predetermined pixel group within the first thresholded image. The predetermined pixel group can be determined by a reference point on the droplet cavity or opening in which the droplet is formed. The predetermined pixel group can be a group corresponding to predetermined x, y values ​​of pixels. Action 806 can use a connected component image analysis algorithm.

[0584] Action 807 filters all remaining pixels of the first thresholded image that do not have pixel groups. The filter operates pixel-by-pixel in the time domain to generate the first filtered image. The first filtered image is the first thresholded image ( Figure 81 The filter is the estimation of the non-activated (e.g., due to features not of interest in the image) portion of the image (774). The filter can be any filter, such as the arbitrary filter described herein.

[0585] Action 808 uses the first filtered image to remove portions determined not to be droplets from the first thresholded image to generate a second image (e.g., Figure 81 The pixels in the image (775) are used to determine the thresholding process. If the corresponding pixel in the first thresholded image is 1 and the corresponding pixel in the first filtered image is less than 0.5, then the pixel in the second image will be set to 1; otherwise, the pixel will be set to 0.

[0586] Action 809 determines a second pixel group connected to a predetermined pixel group within the second image to generate a third image (e.g., Figure 81 Image 776). The third image identifies the second pixel group within the second image. Action 809 finds the group of "illuminated" pixels in the second image that are connected to a predetermined pixel group (e.g., pixels representing openings in which droplets are formed).

[0587] Action 810 determines the first length of the droplet by counting the number of rows containing pixels corresponding to the second pixel group within the third image. That is, the droplet length is determined to be equal to the last "illuminated" row in the pixel group present in action 809. The first length corresponds to a first estimated droplet size.

[0588] Action 811 uses the first image to update the background image. A low-pass filter can be used to update the value of each pixel in the background image. An infinite impulse response filter can be used to update the background image using the first image. Pixels in the background image are updated only for rows below a first length, plus a predetermined safe zone. Pixels in the background image are updated by low-pass filtering the values ​​of the corresponding pixels in the first image.

[0589] Action 812 generates a second thresholded image by comparing the first image with the background image (e.g., Figure 81 Image 772). That is, the first image is obtained by subtracting the background image from it, and on a pixel-by-pixel basis, if the absolute value of each pixel is above the second threshold, it is set to 1, and if the absolute value of each pixel is below the second threshold, it is set to 0 to generate the second thresholded image.

[0590] Action 813 sums the second thresholded rows to create a sum of multiple rows (see...). Figure 81 Image 773). The sum of each row corresponds to a row in the second thresholded image.

[0591] Action 814 begins at the row position of the second thresholded image having the first sum among a plurality of sums corresponding to the first length. The row position is incremented in action 815. Action 816 determines whether the current row position corresponds to the sum of the corresponding row below, for example, a threshold of zero. If not, action 815 is executed again until the current row position corresponds to the sum of the corresponding row that is zero, and then method 803 proceeds to action 817.

[0592] Action 817 determines that the second length is equal to the current row position. The second length corresponds to the second estimated droplet size. Action 818 averages the first and second lengths to determine the average length. The average length corresponds to the third estimated droplet size. By using the first and second lengths to determine the average length, the condensation effect on the inner wall of the drip chamber is mitigated. That is, the purpose of creating two estimates of the droplet length is to compensate for the degree to which each length is affected by the presence of condensation. If a condensed droplet intersects with a growing droplet from the nozzle, the first length tends to underestimate the droplet length. If a condensed droplet intersects with a growing droplet from the nozzle, the second length tends to overestimate the droplet length. When condensation is present, their average provides a better estimate. In the absence of condensation, the estimates are nearly equal. In other embodiments, only the first or second length is used to estimate the droplet size.

[0593] Figure 83 A flowchart of a method 900 for reducing noise from condensation according to an embodiment of the present disclosure is shown. Method 900 includes actions 902-910.

[0594] Action 902 captures an image of the infusion cavity. Action 904 performs a Canny edge detection operation on the image to generate a first processed image. Action 906 performs an AND operation on the pixels on a first side of the axis of the first processed image and their corresponding mirror images on a second side of the axis of the first processed image. That is, action 902 defines the axis in the first processed image and performs an AND operation on each pixel on one side with the pixels on the other side, making the pixels on the other side symmetrical to the pixels on the first side. For example, a 40 (x-axis) by 40 (y-axis) image can have an axis defined between pixel columns 19 and 20. The top left pixel will be pixel (1, 1). The pixel at position (1, 5) will be ANDed with the pixel at (40, 5). The resulting pixel will be used at both positions (1, 5) and (40, 5) to generate a second processed image.

[0595] That is, after performing action 906, action 908 determines whether all pixels have been processed. Action 908 repeats action 906 until all pixels have been processed. Action 910 provides a second processed image as the result of all AND operations.

[0596] Various alternatives and modifications can be conceived by those skilled in the art without departing from this disclosure. Therefore, this disclosure is intended to encompass all such alternatives, modifications, and variations. Furthermore, although several embodiments of this disclosure have been shown in the accompanying drawings and / or discussed herein, it is not intended that this disclosure be limited to these embodiments, but rather that the invention be broad in scope as permitted by the art, and this specification should be read so. Therefore, the above description should not be construed as limiting, but merely as examples of particular embodiments. Moreover, those skilled in the art will conceive of other modifications within the scope and spirit of the appended claims. Other elements, steps, methods, and techniques not substantially different from those described above and / or in the appended claims are also contemplated within the scope of this disclosure.

[0597] The embodiments shown in the accompanying drawings are listed only to illustrate certain examples of this disclosure. Furthermore, the described drawings are illustrative only and not restrictive. In the drawings, for illustrative purposes, the size of some elements may be exaggerated and they are not drawn to a specific scale. Additionally, depending on the context, elements shown with the same reference numerals in the drawings may be the same elements or may be similar elements.

[0598] Where the term "comprising" is used in this specification and claims, the term "comprising" does not exclude other elements or steps.

[0599] When using indefinite or definite articles, when referring to a singular noun, such as “a,” “an,” or “the,” this includes multiples of that noun unless otherwise specifically stated. Therefore, the term “comprising” should not be construed as limited to the items listed thereafter; it does not exclude other elements or steps, so the scope of “an apparatus comprising items A and B” should not be limited to the apparatus comprising only parts A and B. This wording indicates that, relative to this disclosure, only the relevant parts of the apparatus are A and B.

[0600] Furthermore, the terms "first," "second," "third," etc., used in the specification and claims are used to distinguish similar elements and are not necessarily used to describe a sequential or chronological order. It should be understood that such terms are interchangeable where appropriate (unless explicitly disclosed otherwise), and embodiments of the invention described herein can operate in a different order and / or arrangement than those described or shown herein.

Claims

1. A flow meter, comprising: A coupler adapted to be coupled to a drip chamber; A support member, the support member being operatively coupled to the coupler; An image sensor having a field of view and operatively coupled to the support member, wherein the image sensor is positioned to observe the infusion cavity within the field of view; The valve includes: first and second clamshells configured to provide a cavity between the first and second clamshells, the first and second clamshells being configured to receive a tube therebetween and within the cavity; a sac-like structure disposed within the cavity; a pump configured to inflate or de-inflate the sac-like structure to regulate the flow of fluid within the tube; and an actuator coupled to the pump and configured to actuate the pump; and At least one processor, operatively coupled to the image sensor to receive image data from the image sensor, and operatively coupled to the actuator to actuate the valve, wherein the at least one processor is configured to estimate the flow of fluid through the drip chamber and actuate the valve to control the flow of fluid through the drip chamber to achieve a target flow rate. The at least one processor compares an image of the image data with a reference image to estimate at least one parameter of the liquid within the drip chamber.

2. A system comprising: Flow meters, including: A coupler adapted to be coupled to a drip chamber; A support member, the support member being operatively coupled to the coupler; An image sensor having a field of view and operatively coupled to the support member, wherein the image sensor is positioned to observe the infusion cavity within the field of view; The valve includes: first and second clamshells configured to provide a cavity between the first and second clamshells, the first and second clamshells being configured to receive a tube therebetween and within the cavity; a sac-like structure disposed within the cavity; a pump configured to inflate or de-inflate the sac-like structure to regulate the flow of fluid within the tube; and an actuator coupled to the pump and configured to actuate the pump; and At least one processor, operatively coupled to the image sensor to receive image data from the image sensor and operatively coupled to the actuator to actuate the valve, wherein the at least one processor is configured to estimate the flow of fluid through the drip chamber and actuate the valve to control the flow of fluid through the drip chamber to achieve a target flow rate, wherein the at least one processor compares an image of the image data with a reference image to estimate at least one parameter of the liquid within the drip chamber; and A monitoring client, which is operatively communicateable with the flow meter to receive estimated flow of fluid through the drip chamber.

3. A flow meter, comprising: A coupler adapted to be coupled to a drip chamber; A support member, the support member being operatively coupled to the coupler; An image sensor having a field of view and operatively coupled to the support member, wherein the image sensor is positioned to observe the infusion cavity within the field of view; A valve comprising: first and second clamshells configured to provide a cavity between the first and second clamshells, the first and second clamshells being configured to receive a tube therebetween and within the cavity; a sac disposed within the cavity; a pump configured to inflate or de-inflate the sac to regulate the flow of fluid within the tube; and an actuator coupled to the pump and configured to actuate the pump. At least one processor, operatively coupled to the image sensor to receive image data from the image sensor and operatively coupled to the actuator to actuate the valve, wherein the at least one processor is configured to estimate the flow of fluid through the drip chamber and actuate the valve to control the flow of fluid through the drip chamber to achieve a target flow rate. The at least one processor uses distortion of the background pattern caused by the liquid, as indicated by the image data, to determine the presence of free-flow conditions.

4. A flow meter, comprising: A coupler adapted to be coupled to a drip chamber; A support member, the support member being operatively coupled to the coupler; An image sensor having a field of view and operatively coupled to the support member, wherein the image sensor is positioned to observe the infusion cavity within the field of view; A valve, comprising: first and second clamshells configured to provide a cavity between the first and second clamshells, the first and second clamshells configured to receive a tube therebetween and within the cavity; a bladder disposed within the cavity; a pump configured to inflate or de-inflate the bladder to regulate the flow of fluid within the tube; and an actuator coupled to the pump and configured to actuate the pump; and At least one processor, operatively coupled to the image sensor to receive image data from the image sensor, and operatively coupled to the actuator to actuate the valve, wherein the at least one processor is configured to estimate the flow of fluid through the drip chamber and actuate the valve to control the flow of fluid through the drip chamber to achieve a target flow rate. The at least one processor compares an image of the image data with a reference image to estimate at least one parameter of the liquid within the drip chamber.

5. A flow meter, comprising: An image sensor having a field of view, wherein the image sensor is positioned to observe the drip cavity within the field of view; The valve includes: first and second clamshells configured to provide a cavity between the first and second clamshells, the first and second clamshells being configured to receive a tube therebetween and within the cavity; a sac-like structure disposed within the cavity; a pump configured to inflate or de-inflate the sac-like structure to regulate the flow of fluid within the tube; and an actuator coupled to the pump and configured to actuate the pump; and At least one processor is configured to communicate with the image sensor to receive image data therefrom and to communicate with the actuator to actuate the valve, wherein the at least one processor is configured to estimate the flow of fluid through the drip chamber and actuate the valve to control the flow of fluid through the drip chamber to achieve a target flow rate. The at least one processor compares an image of the image data with a reference image to estimate at least one parameter of the liquid within the drip chamber.

6. A system comprising: Flow meter, the flow meter comprising: An image sensor having a field of view, wherein the image sensor is positioned to observe the drip cavity within the field of view; A valve, comprising: first and second clamshells configured to provide a cavity between the first and second clamshells, the first and second clamshells configured to receive a tube therebetween and within the cavity; a bladder disposed within the cavity; a pump configured to inflate or de-inflate the bladder to regulate the flow of fluid within the tube; and an actuator coupled to the pump and configured to actuate the pump; and At least one processor, communicating with the image sensor to receive image data therefrom and with the actuator to actuate the valve, wherein the at least one processor is configured to estimate the flow of fluid through the drip chamber and actuate the valve to control the flow of fluid through the drip chamber to achieve a target flow rate, wherein the at least one processor compares an image of the image data with a reference image to estimate at least one parameter of the liquid within the drip chamber; and A monitoring client, which is operatively communicateable with the flow meter to receive estimated flow of fluid through the drip chamber.

7. A flow meter, comprising: An image sensor having a field of view, wherein the image sensor is positioned to observe the drip cavity within the field of view; A valve, comprising: first and second clamshells configured to provide a cavity between the first and second clamshells, the first and second clamshells configured to receive a tube therebetween and within the cavity; a bladder disposed within the cavity; a pump configured to inflate or de-inflate the bladder to regulate the flow of fluid within the tube; and an actuator coupled to the pump and configured to actuate the pump; and At least one processor, communicating with the image sensor to receive image data therefrom and with the actuator to actuate the valve, wherein the at least one processor is configured to estimate the flow of fluid through the drip chamber and actuate the valve to control the flow of fluid through the drip chamber to achieve a target flow rate. The at least one processor uses distortion of the background pattern caused by the liquid, as indicated by the image data, to determine the presence of free-flow conditions.

8. A flow meter, comprising: An image sensor having a field of view, wherein the image sensor is positioned to observe the drip cavity within the field of view; The valve includes: first and second clamshells configured to provide a cavity between the first and second clamshells, the first and second clamshells being configured to receive a tube therebetween and within the cavity; a sac-like structure disposed within the cavity; a pump configured to inflate or de-inflate the sac-like structure to regulate the flow of fluid within the tube; and an actuator coupled to the pump and configured to actuate the pump; and At least one processor, communicating with the image sensor to receive image data therefrom and with the actuator to actuate the valve, wherein the at least one processor is configured to estimate the flow of fluid through the drip chamber and actuate the valve to control the flow of fluid through the drip chamber to achieve a target flow rate. The at least one processor compares an image of the image data with a reference image to estimate at least one parameter of the liquid within the drip chamber.

Images