Patent Publication Number: US-2021170095-A1

Title: Rotary microfluidic medical pump

Description:
RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. section 119(e) from U.S. Provisional Patent Application No. 62/945,033, filed Dec. 6, 2019, by P. DiPerna et al., and titled “Rotary Microfluidic Pump”, and from U.S. Provisional Patent Application No. 62/944,999, filed Dec. 6, 2019, by K. DiPerna et al., and titled “Medical Device Training Module”, each of which is hereby incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     The delivery of therapeutic and non-therapeutic medical fluids is commonly performed intravenously (IV) or subcutaneously using an infusion catheter or cannula and a syringe pump. The mechanism of such syringe type pumps typically compresses a syringe plunger within a corresponding syringe housing in a controlled fashion to provide accurate dosing. For ambulatory pumps this mechanism may be scaled down but generally the small, powerful, and accurate motor that is required for such syringe pumps is expensive. Syringe pumps typically also rely on a motor driven lead screw and attachment to a compressing plunger to not only control the delivery of fluids but also to prevent the unexpected delivery of fluids to a patient over a prolonged period of use by the patient. The accuracy of syringe type pumps as well as other common medical pumps, including peristaltic type pumps, may be compromised by changes in environmental conditions including variation in ambient temperature, changes in ambient pressure as well as other factors. What have been needed are improved pumping mechanisms and methods that are reasonably priced and that can reliably deliver small quantities of medical fluids in an accurate and consistent manner without susceptibility to environmental variations. 
     SUMMARY 
     Some embodiments of a medical pump system may include a reservoir cartridge assembly having a fluid reservoir. The fluid reservoir may include a liquid volume, an air volume and a flexible membrane disposed between the liquid volume and air volume which is configured to provide a fluid tight barrier between the liquid volume and air volume. The reservoir cartridge assembly may also include a pump chamber assembly that has a pump chamber with an interior volume which is at least partially bounded by a pump housing. The pump chamber may further include an inlet port in fluid communication with the interior volume and with the liquid volume of the fluid reservoir, and a resilient inlet membrane which is disposed adjacent the inlet port, which is spaced from the inlet port when in a relaxed state, and which is sufficiently distendable towards the inlet port to seal the inlet port in a compressed state. The pump chamber may also include an outlet port in fluid communication with the interior volume and with an outlet conduit. The pump chamber assembly may also include and a resilient outlet membrane which is disposed adjacent the outlet port, which is spaced from the outlet port when in a relaxed state, and which is sufficiently distendable towards the outlet port to seal the outlet port in a compressed state. The pump chamber may also have a displacement chamber disposed within the interior volume and a resilient displacement membrane. The resilient displacement membrane may be disposed adjacent the displacement chamber, form at least a portion of a boundary of the displacement chamber, be sufficiently inwardly distendable from a relaxed state to reduce the volume of the displacement chamber when in a compressed state, and be sufficiently resilient to rebound and increase the volume of the displacement chamber when released from the compressed state. The medical pump system may also include an actuator assembly that is configured to be operatively and releasably coupled to the reservoir cartridge assembly. The actuator assembly may include a cam assembly including an inlet cam lobe which is operatively coupled to the resilient inlet membrane, an outlet cam lobe which is operatively coupled to the resilient outlet membrane, and a displacement cam lobe which is operatively coupled to the displacement membrane. The actuator assembly may also have a motor operatively coupled to the cam assembly and a controller operatively coupled to the motor. 
     Some embodiments of a reservoir cartridge assembly which is configured to be operatively and releasably coupled to an actuator assembly of a medical pump system may include a reservoir base and a fluid reservoir disposed on the reservoir base. The fluid reservoir may include a liquid volume, an air volume and a flexible membrane disposed between the liquid volume and air volume. The flexible membrane may be configured to provide a fluid tight barrier between the air volume and the liquid volume. The reservoir cartridge assembly may further include a pump chamber assembly secured to the reservoir base. The pump chamber assembly may have a pump chamber with an interior volume which is at least partially bounded by a pump housing. The pump chamber assembly may also have an inlet port in fluid communication with the interior volume and in fluid communication with the liquid volume of the fluid reservoir. The pump chamber assembly may further include a resilient inlet membrane which is disposed adjacent the inlet port, which is spaced from the inlet port when in a relaxed state, and which is sufficiently distendable towards the inlet port to seal the inlet port in a compressed state. An outlet port in fluid communication with the interior volume and with an outlet conduit is also included with the pump chamber assembly, as well as a resilient outlet membrane which is disposed adjacent the outlet port, which is spaced from the outlet port when in a relaxed state, and which is sufficiently distendable towards the outlet port to seal the outlet port in a compressed state. The pump chamber assembly also has a displacement chamber disposed within the interior volume and a resilient displacement membrane which is disposed adjacent the displacement chamber, which forms at least a portion of a boundary of the displacement chamber, which is sufficiently inwardly distendable from a relaxed state to reduce the volume of the displacement chamber when in a compressed state. The resilient displacement membrane is also sufficiently resilient to increase the volume of the displacement chamber when released from the compressed state. 
     Some embodiments of an actuator assembly which is configured to be operatively and releasably coupled to a reservoir cartridge assembly of a medical pump system may include an actuator chassis and a controller secured to the actuator chassis. The actuator assembly may further include a cam assembly which is disposed on the actuator chassis and which includes an inlet cam lobe which is configured to be operatively coupled to a resilient inlet membrane, an outlet cam lobe which is configured to be operatively coupled to a resilient outlet membrane, a displacement cam lobe which is configured to be operatively coupled to a displacement membrane, and a vent cam lobe which is configured to be operatively coupled to a vent membrane. The actuator assembly may also include a motor which is operatively coupled to the cam assembly and a controller. The actuator assembly may also include a pressure sensor which is operatively coupled to the controller. 
     Some embodiments of a pump assembly for medical use may include a pump chamber assembly having a pump chamber with an interior volume which is at least partially bounded by a pump housing. The pump chamber assembly may also have an inlet port in fluid communication with the interior volume and a resilient inlet membrane which is disposed adjacent the inlet port, which is spaced from the inlet port when in a relaxed state, and which is sufficiently distendable towards the inlet port to seal the inlet port in a compressed state. The pump chamber assembly may also include an outlet port in fluid communication with the interior volume and a resilient outlet membrane which is disposed adjacent the outlet port, which is spaced from the outlet port when in a relaxed state, and which is sufficiently distendable towards the outlet port to seal the outlet port in a compressed state. A displacement chamber may further be disposed within the interior volume. A resilient displacement membrane may be disposed adjacent the displacement chamber, form at least a portion of a boundary of the displacement chamber, be sufficiently inwardly distendable from a relaxed state to reduce the volume of the displacement chamber when in a compressed state, and be sufficiently resilient to increase the volume of the displacement chamber when released from the compressed state. The pump assembly may also include an actuator assembly which has a cam assembly with a cam shaft having an inlet cam lobe which is operatively coupled to the resilient inlet membrane, an outlet cam lobe which is operatively coupled to the resilient outlet membrane, and a displacement cam lobe which is operatively coupled to the displacement membrane. The actuator assembly may also have a motor operatively coupled to the cam assembly. 
     Some embodiments of a method of pumping a medical fluid may include coupling a reservoir cartridge assembly to an actuator assembly to form a medical pump system and filling a liquid volume of a fluid reservoir of the reservoir cartridge assembly with a therapeutic fluid as well as venting air from an air volume disposed adjacent the liquid volume. The method may also include disposing an outlet conduit of the pump chamber assembly in fluid communication with a subcutaneous delivery site within the patient&#39;s body and delivering a controlled rate of infusion of the therapeutic fluid to the subcutaneous delivery site of the patient by performing sequential pumping cycles of the medical pump system carried out according to a predetermined delivery protocol. 
     Some embodiments of a medical pump training system may include an actuator assembly having an actuator chassis and a controller secured to the actuator chassis. The medical pump training system may also include a training cartridge having a cartridge housing which is configured to releasably couple to the actuator assembly and which includes an identifying feature that is configured to be operatively coupled to the controller of the actuator assembly and provide information to the controller identifying the training cartridge as a non-therapeutic cartridge. 
     Some embodiments of a training cartridge for a medical pump system may include a cartridge housing that is configured to couple to an actuator assembly of the medical pump system. The training cartridge may also include an identifying feature disposed on the cartridge housing that is configured to be operatively coupled to a controller of the actuator assembly and provide information to the controller identifying the training cartridge. 
     Some embodiments of a multi-function medical pump may include an actuator assembly, having a latch mechanism constructed and arranged to removably couple to a cartridge and a selection mechanism that determines a type of cartridge. The multi-function medical pump may also include the cartridge, wherein a first type of cartridge is a reservoir cartridge assembly that is permitted by the latch mechanism to couple to the actuator assembly for a single use operation, and wherein a second type of cartridge is a training cartridge that is permitted by the latch mechanism to couple to the actuator assembly for multiple training operations. 
     Some embodiments of a method for operating a multi-function medical pump may include removably coupling an actuator assembly to a cartridge and determining by a selection mechanism a type of cartridge which has been assembled. The method may also include coupling by a latch mechanism of the multi-function medical pump the actuator assembly and the reservoir cartridge assembly for a single use operation in response to determining that the type of cartridge is a reservoir cartridge assembly. The method may also include coupling by the latch mechanism the actuator assembly and the training cartridge for multiple training use operations in response to determining that the type of cartridge is a training cartridge. 
     Certain embodiments are described further in the following description, examples, claims and drawings. These features of embodiments will become more apparent from the following detailed description when taken in conjunction with the accompanying exemplary drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic depiction of a medical pump system embodiment. 
         FIG. 2  is a perspective view of a medical pump system embodiment. 
         FIG. 3  is an elevation view in partial section of the medical pump system embodiment of  FIG. 2  deployed on and releasably secured to a patient&#39;s skin with a distal end of a flexible cannula of a patient port disposed in subcutaneous target tissue. 
         FIG. 4  is an exploded view of the medical pump system embodiment of  FIG. 2 . 
         FIG. 5  is an exploded view of an actuator assembly embodiment of the medical pump system embodiment of  FIG. 2 . 
         FIG. 6  is a perspective view of the actuator assembly embodiment of  FIG. 5  shown without the outer shell for purposes of illustration. 
         FIG. 7  is a bottom view of the actuator assembly embodiment of  FIG. 6 . 
         FIG. 8  is an exploded view of a reservoir cartridge embodiment of the medical pump system embodiment of  FIG. 2 . 
         FIG. 8A  is an elevation view in longitudinal section of a pushrod guide of  FIG. 8  taken along lines  8 A- 8 A of  FIG. 8 . 
         FIG. 8B  is a transverse section of the pushrod guide of  FIG. 8A  taken along lines  8 B- 8 B of  FIG. 8A . 
         FIG. 8C  is a longitudinal section of a continuous pump membrane embodiment of  FIG. 8  taken along lines  8 C- 8 C of  FIG. 8 . 
         FIG. 9  is a perspective view of the medical pump system of  FIG. 2  shown without the outer shell for purposes of illustration. 
         FIG. 10  is a perspective view in transverse section of the medical pump system embodiment of  FIG. 2 . 
         FIG. 11  is an enlarged view of the medical pump system embodiment of  FIG. 10  indicated by the encircled portion  11 - 11  in  FIG. 10 . 
         FIG. 12  is a top view in perspective of a subassembly including a reservoir base embodiment of the reservoir cartridge assembly and a cam shaft and drive train embodiment of the actuator assembly with the cam shaft of the actuator assembly operatively coupled to the pushrods of the reservoir cartridge assembly. 
         FIG. 13  is a side view of the subassembly of  FIG. 12 . 
         FIG. 14  is a section view of the pump assembly of  FIG. 13  taken along lines  14 - 14  of  FIG. 13 . 
         FIG. 14AA  is an enlarged view of the reservoir cartridge assembly of  FIG. 14  indicated by the encircled portion  14 AA- 14 AA in  FIG. 14 . 
         FIGS. 14A-14C  are schematic section views of the pump assembly of  FIG. 13  illustrating a pumping sequence. 
         FIG. 15  is a transverse cross section view of the medical pump system embodiment of  FIG. 2 . 
         FIG. 16  is an enlarged view of the medical pump system embodiment of  FIG. 15  indicated by the encircled portion  16 - 16  of  FIG. 15 . 
         FIG. 17  is an enlarged bottom view partially cut away of the reservoir cartridge assembly embodiment and showing a latch spring embodiment thereof. 
         FIG. 18  is an enlarged perspective view, partially cut away of the reservoir cartridge assembly embodiment and showing a fill port embodiment thereof. 
         FIGS. 19A-19C  are transverse cross section views of a reservoir cartridge subassembly and illustrating a fill sequence of the fluid volume of a fluid reservoir thereof. 
         FIG. 20  is a schematic representation of a pump assembly embodiment. 
         FIG. 21  is a schematic representation of a medical pump training system embodiment. 
         FIG. 22  is an exploded view of a training cartridge embodiment. 
         FIG. 23  is a perspective view of the training cartridge embodiment of  FIG. 22 . 
         FIG. 24  is a flowchart indicating a method of communication between components of a medical pump training system embodiment. 
     
    
    
     The drawings are intended to illustrate certain exemplary embodiments and are not limiting. For clarity and ease of illustration, the drawings may not be made to scale, and in some instances, various aspects may be shown exaggerated or enlarged to facilitate an understanding of particular embodiments. 
     DETAILED DESCRIPTION 
     As discussed above, delivery of therapeutic fluids or non-therapeutic medical fluids is commonly performed intravenously (IV) or subcutaneously using systems that include pumps such as syringe pumps, peristaltic pumps as well as others. However, these types of pumps do not always perform consistently and cost effectively, particularly when used in varying environmental conditions. Medical pump embodiments and related components that address issues such as these are discussed in U.S. patent application Ser. No. 16/028,256, filed Jul. 5, 2018, by P. DiPerna et al., titled “Medical Pump with Flow Control”, U.S. patent application Ser. No. 16/520,521, filed Jul. 24, 2019, by P. DiPerna et al., titled “Subcutaneous Access Hub with Multiple Cannula Ports”, and U.S. patent application Ser. No. 15/122,132, Publication No. US 2016/0361489 A1, filed Mar. 3, 2015, by P. DiPerna, titled “Fluid Delivery Pump”, each of which is incorporated by reference herein in its entirety. 
     In addition, some or all of these issues may be addressed by improved medical pumping mechanisms that may include a positive displacement pump mechanism. Discussed below are embodiments of micro-positive displacement pump embodiments actuated by a cam assembly that may, in some cases, include a single camshaft synching an input valve and an output valve of a pump chamber. For some embodiments, such valve embodiments may include the use of one or more diaphragms, also referred to herein as resilient membranes, that are displaced by rotating lobes of the cam assembly. For some embodiments, the lobes of the cam assembly may be rotated by a DC motor coupled through a planetary gearset. Such positive displacement pump embodiments may be incorporated into a medical pump system that includes a reservoir cartridge assembly and a cooperating actuator assembly that may be configured to provide both convenient and economical use for an end user patent of the system. 
     It should be noted that in many cases, the pump embodiments discussed herein may be operated directly by medical professionals that are treating patients. In many cases, the pump embodiments discussed herein may also be operated directly by individual end users that suffer from a particular medical condition, such as diabetes or any other condition that may require accurate and reliable infusion of a therapeutic fluid. Such individual end users may be using such pump system embodiments to administer therapeutic fluids to themselves under the direction of a medical professional or any other suitable direction. In either case, the person receiving such a treatment will generally be referred to herein as a patient, although the terms end user, patient and the like may be used interchangeably. 
     For such embodiments, a full revolution of the cam shaft may provide a single fill and dispense cycle for a small volume of fluid from the pump chamber of the medical pump system in some cases. The inlet port and outlet port may be closed by the respective camshaft lobes by a method wherein upon rotation at a particular phase the respective cam lobe pushes down on an appropriate piston element, which may also be referred to herein as a pushrod, to compress the resilient membrane and complete a sealed closure of the port. Timing of the inlet cam lobe and outlet cam lobe may be configured by design such that either the inlet port, outlet port, or both inlet port and outlet port may be closed off at certain phases of the cam lobe rotation. The cam assembly may be configured to sequence the displacement and direction of the pushrods in order to ensure that there is never an open fluid path from a fluid reservoir of a reservoir cartridge assembly to the body of the patient, e.g., via an outlet conduit of the medical pump system to a hub of a patient port that is in fluid communication with a subcutaneous portion of a patient&#39;s body that may include a Luer™ connection to an infusion set or the like. For some such embodiments, there may be four unique states of the pushrods, e.g.: a fill state, a pre-dispense state, a dispense state, and a pre-fill state. 
     For some embodiments, the motor may be driven through the discharge of a capacitor which can also be useful to reduce the risk of a continuous runaway condition for the motor. The motor rotation speed may be controlled by pulsing a discharge of such a capacitor. The frequency of discharged pulses may be controlled by embedded firmware which may be configured to support partial pumping cycles, partial dispense cycles or the like. An electrical switch such as a micro-switch may be positioned onto a shaft of the cam assembly to confirm a proper or otherwise desired rotation state of the cam shaft and/or motor shaft with respect to output steps of the motor. 
     In some cases, a pressure sensor disposed in the actuator assembly may be configured to interface with the reservoir cartridge assembly and used to determine a pressure within an air volume of the fluid reservoir of the reservoir cartridge assembly. In some cases, the pressure sensor may be used to measure a pressure differential within the air volume when fluid is drawn from the liquid volume of the fluid reservoir to fill the pump chamber thereby reducing a volume of liquid disposed in the liquid volume. Such pressure readings may also be used to provide increased sensitivity for detecting occlusions in a fluid path of the outlet port, or outlet conduit, such as the infusion tubing, between the outlet port and hub of the infusion set. 
     Such a medical pump system or components thereof may be useful for delivery of non-therapeutic fluids or therapeutic fluids such as saline, antibiotics, dextrose solutions, pain medications, peptides and the like. Some therapeutic fluids that may be delivered by the medical pump system embodiments discussed herein may include therapeutic fluids used for the treatment of diabetes as well as other related medical conditions. In particular, such medical pump systems or components thereof may be useful for the continuous subcutaneous delivery of insulin, including standard insulin compositions such as Novolog®, Lyumjev™, Fiasp®, and Humalog®, fast-acting insulins such as Lispro, Aspart, and Glulisine, and slow-acting insulin compositions such as insulin Glargine and insulin Detemin. Other therapeutic fluids used for the treatment of diabetes or any other suitable medical condition where accurate and cost effective delivery of fluids to a patient is needed such as liquid stable glucagon may also be delivered. Such medical pump systems may be particularly useful where such fluid delivery is being carried out in varying environmental conditions and/or where ambulatory delivery is desirable. 
     For some medical pump system embodiments, cost effectiveness and efficiency may be realized by identifying a first set of components that may be included with a durable element and a second set of components that may be included with a low use or disposable single use type element of a medical pump system. For such embodiments, the more costly and/or more durable components may be included with the first set of components of the durable element in order to reuse and make efficient use of these types of components. Less expensive components, components that require frequent refreshing and/or those components that require sterilization before each use may be incorporated into the second set of components of the disposable element. As such, for some medical pump system embodiments discussed herein, the motor, transmission, cam assembly, sensitive pressure sensor, and controller which may include a microprocessor and memory may be included in a reusable actuator assembly that may be categorized as the durable element. Components such as a fluid reservoir, pump chamber and its associated elements and a power source such as a battery may be included in the reservoir cartridge assembly which may be categorized as the less durable or disposable element. Additional sub-assemblies may include a mount bracket that is configured to detachably mount the medical pump assembly to the patient&#39;s body with a single use adhesive pad that is generally serviceable for about 1 day to about 3 days, a service life that may be similar to the service life of embodiments of the reservoir cartridge assembly. In some cases, the durable element of the actuator may have a service life of up to about 6 months or more. 
     Pump assembly embodiments discussed herein may be configured to reduce or eliminate the possible detrimental effects of harsh and/or sudden mechanical movements upon the molecules of certain therapeutic fluids such as insulin. As such, the device and method embodiments for fluid delivery discussed herein are consistent with the cam lobes of the cam assembly embodiments rotating slowly (in some cases up to only about two revolutions per minute during bolus delivery) allowing the cam lobes to gently open and close respective ports controlled thereby so as to move the molecules of the therapeutic fluid through the pump assembly embodiments without damage to the molecules of the therapeutic fluids, such as for example insulin molecules. 
     Referring generally to  FIGS. 1-10 , a medical pump system embodiment  10  is shown that includes two major components including a reservoir cartridge assembly  12  and an actuator assembly  14  that are configured to be coupled together with a latch mechanism  16  that holds them securely together, but that can later be released to install a new reservoir cartridge assembly  12  into the reusable actuator assembly  14 . A schematic overview of an embodiment of the medical pump system  10  is shown in  FIG. 1  wherein a dashed line indicates a coupling interface between the actuator assembly  14  and the reservoir cartridge assembly  12 , and the various components thereof. The interconnecting lines between the various schematic components of  FIG. 1  may include any type of suitable conduit that may be useful for operatively interconnecting the respective components such as information conducting conduits, power conducting conduits or the like including conductive wires, optical fibers, wireless connectivity etc. In general, for some embodiments, the actuator assembly embodiment  14  may be a durable element that may be used over several months or more and the reservoir cartridge assembly  12  may be a disposable single use element that is replaced on a more frequent basis, such as every few days. The medical pump system embodiments  10  discussed herein are suitable for ambulatory use and may have outer dimensions suitable for such use. In some cases, embodiments of the medical pump systems  10  discussed herein may have a length of about 2.0 inches to about 3.0 inches, a width of about 1.2 inches to about 1.8 inches and a thickness of about 0.4 inches to about 0.7 inches. 
     In some cases, the reservoir cartridge assembly  12  may include a fluid reservoir  18  as shown in  FIGS. 1 and 4  which may have an outer structure or container that is rigid and resistant to flexing in response to pressure differentials imposed between an inner volume thereof and the area disposed outside of the outer structure or container. In some cases, the fluid reservoir  18  may also have a liquid volume  22 , an air volume  24  and a flexible membrane  28  disposed between the liquid volume  22  and air volume  24 . The flexible membrane  28  may be made from a fluid tight material and thus provides a fluid tight barrier between the air volume  24  and liquid volume  22 . For some embodiments, the flexible membrane  28  may be molded by methods such as cold molding in order to conform to the inner contour shape of the fluid reservoir cavity of the reservoir base  94 . The outer perimeter of the flexible membrane may be sealingly secured to the outer perimeter of the fluid reservoir cavity of the reservoir base  94  by methods such as heat sealing, adhesive bonding or the like. 
     A pump chamber assembly  32 , as also seen in  FIG. 4 , of the reservoir cartridge assembly  12  may include a pump chamber  34 , as shown in  FIGS. 14 and 14AA , having an interior volume  36  which is at least partially bounded by a pump housing  38 . An inlet port  42  of the pump chamber assembly  32  is disposed in fluid communication with the interior volume  36  of the pump chamber  34  and also with the liquid volume  22  of the fluid reservoir  18  which allows therapeutic fluid  50  disposed in the liquid volume  22  of the fluid reservoir  18  to flow into the pump chamber  34  when the inlet port  42  is open. A resilient inlet membrane  44  is disposed adjacent the inlet port  42  and is spaced from the inlet port  42  when in a relaxed state without any external force being applied to it. The resilient inlet membrane  44  is also sufficiently distendable towards the inlet port  42  to seal the inlet port when the resilient inlet membrane  44  is in a compressed state biased towards the inlet port  42 . The resilient inlet membrane  44  may also include a dimple  46  that aligned with and disposed towards the inlet port  42  and configured to help seal the inlet port  42  when the resilient inlet membrane  44  is pressed into the inlet port  42 . 
     An outlet port  52  is disposed in fluid communication with the interior volume  36  of the pump chamber  34  and is also disposed in fluid communication with an outlet conduit  56  which allows therapeutic fluid  50  to flow out of the outlet port  52  from the pump chamber  34  when the outlet port  52  is open. A resilient outlet membrane  54  is disposed adjacent the outlet port  52  and is spaced from the outlet port  52  when in a relaxed non-distended state. The resilient outlet membrane  54  is also sufficiently distendable towards the outlet port  52  to seal the outlet port  52  when in a compressed state distended towards the outlet port  52 . The resilient outlet membrane  54  may also include a dimple  58  that aligned with and disposed towards the outlet port  52  and is configured to help seal the outlet port  52  when the resilient outlet membrane  54  is pressed against the outlet port  52 . A displacement chamber  62  is also disposed within the interior volume  36  of the pump chamber  34 . A resilient displacement membrane  64  is disposed adjacent the displacement chamber  62  and forms at least a portion of a boundary of the displacement chamber  62 . The resilient displacement membrane  64  is also sufficiently inwardly distendable from a relaxed state to reduce the volume of the displacement chamber  62  when in a compressed state distended inwardly towards the opposite wall of the interior volume  36  of the pump chamber  34 . The resilient displacement membrane  64  is also sufficiently resilient to rebound and increase the volume of the displacement chamber  62  when released from the compressed state thereby moving away from the wall opposite the resilient displacement membrane  64 . In general, the resilient inlet membrane  44 , resilient outlet membrane  54  and resilient displacement membrane  64  may be distended, compressed, and relaxed by the actuation of respective pushrods with valve ends thereof disposed in contact with the resilient membranes  44 ,  54 ,  64  discussed in more detail below. 
     The pushrods in contact with the various resilient membranes  44 ,  54 ,  64  of the pump chamber assembly  32  may be actuated by a cam assembly  68  of the actuator assembly  14 . For some embodiments, the actuator assembly  14  may be configured to be operatively and releasably coupled to the reservoir cartridge assembly  12  as noted above. Embodiments of the actuator assembly  14  may include the cam assembly  68  which may have a cam shaft  70  with an inlet cam lobe  72  which is operatively coupled to the resilient inlet membrane  44 , an outlet cam lobe  76  which is operatively coupled to the resilient outlet membrane  54 , and a displacement cam lobe  80  which is operatively coupled to the resilient displacement membrane  64 . The actuator assembly  14  may also include a motor  84  operatively coupled to the cam assembly  68  and a controller  88  operatively coupled to the motor  84 . In some cases, the motor  84  may be coupled to the controller  88  with a flexboard assembly conduit  85  as seen in  FIG. 5 . 
     For some embodiments, the reservoir cartridge assembly  12  may further include an inlet pushrod  74  which is operatively disposed between the inlet cam lobe  72  and the resilient inlet membrane  44 , an outlet pushrod  78  operatively disposed between the outlet cam lobe  76  and the resilient outlet membrane  54  and a displacement pushrod  82  operatively disposed between the displacement cam lobe  80  and the resilient displacement membrane  64 . A pushrod guide  92  may be secured to a reservoir base  94  of the reservoir cartridge assembly  12 . Such a pushrod guide may include a rigid configuration with an inlet pushrod bore disposed about and guiding the inlet pushrod  74 , a displacement pushrod bore disposed about and guiding the displacement pushrod  82  and an outlet pushrod bore disposed about and guiding the outlet pushrod  78 . Regarding the respective inlet and outlet valve assemblies discussed above, a combination of the inlet port  42 , resilient inlet membrane  44 , inlet pushrod  74  and associated portion of the pushrod guide  92  may be said to form an inlet valve assembly  75 . A combination of the outlet port  52 , resilient outlet membrane  54 , outlet pushrod  78  and associated portion of the pushrod guide  92  may be said to form an outlet valve assembly  79 . In addition, with regard to this configuration, the resilient inlet membrane  44  may be said to be operatively coupled to the inlet cam lobe  72  by the inlet pushrod  74 , the resilient outlet membrane  54  may be said to be operatively coupled to the outlet cam lobe  76  by the outlet pushrod  78 , and the resilient displacement membrane  64  may be said to be operatively coupled to the displacement cam lobe  80  by the displacement pushrod  82 . 
     In some cases, the reservoir cartridge assembly  12  may further include a vent port  100  and a resilient vent membrane  102  which is disposed adjacent the vent port  100  and which is also spaced from the vent port  100  when in a relaxed state as shown in  FIG. 14AA . The resilient vent membrane  102  is also sufficiently distendable towards the vent port  100  to seal the vent port  100  when the resilient vent membrane  102  is in a compressed state distended towards the vent port  100 . In addition, the cam assembly  68  may further include a vent cam lobe  104  which is operatively coupled to the resilient vent membrane  102  by a vent pushrod  106  which is operatively disposed between the vent cam lobe  104  and the resilient vent membrane  102 . In addition, a vent pushrod guide portion  108  of the pushrod guide  92  may be secured in fixed relation to the pump housing  38  and include a vent pushrod bore  110  disposed about and guiding the vent pushrod  106 . A combination of the vent port  100 , resilient vent membrane  102 , vent pushrod  106  and vent pushrod guide portion  108  may be said to form a vent valve assembly  109 . The resilient vent membrane  102  may also include a dimple  103  that is aligned with and disposed towards the vent port  100  and configured to help seal the vent port  100  when the resilient vent membrane  103  is pressed into the vent port  100 . In some cases, the state of the vent valve assembly  109  may determine whether the air volume  24  of the fluid reservoir  18  is vented to the ambient atmosphere or not. In particular for some embodiments, if the vent port  100  of the vent valve assembly  109  is closed, as shown in  FIG. 14A , then the air volume  24  is not vented to the ambient atmosphere outside of the medical pump system  10 . If the vent port  100  of the vent valve assembly  109  is open, as shown in  FIG. 14C , then the air volume  24  is vented to the ambient atmosphere through the vent valve assembly  109  as indicated by the arrow  107 . As such, the vent valve assembly  109  acts as a gateway for a vent conduit pathway  111  that extends from the air volume  24  to the ambient atmosphere disposed outside the medical pump system  10 . 
     For some embodiments, the pushrod guide  92  and pushrod bores disposed therein may be configured such that longitudinal axes of the respective pushrod bores, including the inlet pushrod bore, outlet pushrod bore, displacement pushrod bore and vent pushrod bore, are all parallel to each other and may also all lie in a common plane as shown in the embodiment of  FIGS. 8, 8A and 8B . As such, the pushrods associated with this configuration, including the inlet pushrod  74 , outlet pushrod  78 , displacement pushrod  82  and vent pushrod  106 , may also have respective longitudinal axes that are all parallel to each other and lie in a common plane when assembled in the pushrod guide  92 . The pushrods including the inlet pushrod  74 , outlet pushrod  78 , displacement pushrod  82  and vent pushrod  106 , may have a generally cylindrical configuration with a flanged portion disposed at an inward end of the pushrod. The flanged portion may extend radially outward so as to be mechanically captured by a corresponding expanded section of each respective pushrod bore, with each expanded section also being disposed at the inward end of the pushrod guide  92 . In such cases, the flanged portion of each pushrod may be small enough to fit and slide easily within the expanded section of its respective pushrod bore, but too large in transverse dimension to fit into the nominal bore. The axial length of the expanded section of each pushrod bore may be sufficiently greater than an axial length of each respective flanged portion such that each pushrod which is slidingly disposed within its pushrod bore of the pushrod guide  92  is configured to slide in an axial direction within the pushrod bore over a limited axial range determined by the axial length of the expanded section. For this linearly oriented configuration, the associated pump chamber  34  may also be similarly configured with the shallow elongate interior volume  36  of the pump chamber  34  having the inlet port  42 , displacement chamber  62  and outlet port  52  lying along a line with the displacement chamber  62  disposed between the inlet port  42  and outlet port  52 . For some embodiments, the pump chamber  34  may be configured as a shallow rectangular shape with radiused ends bounded on one side by the pump chamber housing  38  and on the other side by the resilient continuous pump membrane  124  as seen in  FIG. 8C . The inlet port  42  and outlet port  52  are formed into the pump chamber housing  38 . Other such pump chamber embodiments  34  may also have other suitable configurations wherein the inlet port  42 , outlet port  52  and displacement chamber  62  do not all lie along the same line, nor would the associated resilient membranes and associated pushrods. The linear configuration of the embodiment shown may be useful for pump assemblies that utilize a single linear cam shaft  70  that includes the multiple lobes associated with each portion of the pump chamber  34  and/or vent valve assembly  109 . 
     For some embodiments, the vent valve assembly  109 , and particularly an inner volume thereof, may be disposed in fluid communication with an outlet end  116  of a pre-valve vent conduit  118  of the vent conduit pathway  111  as shown in  FIGS. 14A-C , and  19 A-B. The pre-valve vent conduit  118  extends from the vent valve assembly  109  to an inlet end  120  of the pre-valve vent conduit  118  as shown in  FIGS. 12 and 14 , with the inlet end  120  being disposed adjacent and in fluid communication with the air volume  24  of the fluid reservoir  18 . The pre-valve vent conduit  118  extends through the reservoir cartridge assembly  12  through a channel formed by a slot in the reservoir base  94  that is sealed on a bottom side thereof by an upper surface of a latch spring cover plate  113  as shown in  FIGS. 8, 18, 19A and 19B . The latch spring cover plate  113  also includes a latch release slot  115  that provides limited access for release of the latch spring  166  discussed in more detail below. The latch release slot  115  may also serve as the final access point to ambient atmosphere for the vent conduit pathway  111 . 
     The vent valve assembly  109 , and particularly the inner volume thereof, may also be disposed in fluid communication with an inlet end  112  of a post-valve vent conduit  114  of the vent conduit pathway  111 , as shown in  FIGS. 14A-B  and  19 A-B. The post-valve vent conduit  114  is also in fluid communication with the ambient atmosphere that surrounds the medical pump system  10  at an outlet end  117  thereof. The vent path of the post-valve vent conduit  114  begins at the inlet end  112  adjacent the vent valve assembly  109  and then vents into an interior volume space disposed between the reservoir cartridge assembly  12  and the actuator assembly  14 , this interior volume space being sealed around a perimeter thereof as discussed in more detail below. The vent path then continues to an air gap  119  disposed between an outside surface of a latch post  164  that is secured to an actuator chassis  162  and a latch post bore  121  disposed in the reservoir base  94  of the reservoir cartridge assembly  12 . The latch post  164  and latch post bore are components of the latch mechanism  16  discussed in more detail below. The air gap  119  and latch post bore  121  are shown in  FIGS. 8, 12, and 14AA . The vent path then continues from the air gap  119  to the latch release slot  115  disposed on the bottom of the reservoir cartridge assembly  12  and then out to ambient atmosphere. For embodiments such as these, the latch release slot  115  may serve as the outlet end  117  of the post-valve vent conduit  114 . The tortuous nature of the vent conduit pathway  111  that includes the pre-valve vent conduit  118  and the post-valve vent conduit  114  may be useful in some circumstances in order to reduce the intrusion of contaminants into the vent conduit pathway  111  as well as the vent valve assembly  109  and air volume  24 . In addition, as the vent conduit pathway  111  is included within the reservoir cartridge assembly  12 , which may, in some cases, be disposable and used for only a limited amount of time, there is also a limited amount of time for contaminants such as dust, moisture etc. to accumulate in the vent conduit pathway  111 . 
     In some cases, a single continuous pump membrane  124 , as shown in  FIGS. 8, 8C and 14AA , may be configured to be elastically resilient and to include the resilient inlet membrane  44 , resilient displacement membrane  64 , and resilient outlet membrane  54 . In some instances, this single continuous pump membrane  124  may also include the resilient vent membrane  102 . Although, in some cases, each of the inlet cam lobe  72 , outlet cam lobe  76 , displacement cam lobe  80  and vent cam lobe  104  may be actuated by a separate cam and motor mechanism, in general the inlet cam lobe  72 , outlet cam lobe  76 , and displacement cam lobe  80  may be disposed on the cam shaft  70  which may have a continuous unitary configuration wherein all of the cam lobes disposed thereon are secured in fixed relation to each other and rotate together. In addition, for some such integrated cam shaft embodiments  70 , the vent cam lobe  104  may also be included and disposed in fixed relation to the inlet cam lobe  72 , outlet cam lobe  76  and displacement cam lobe  80  and rotate together with those cam lobes. For this type of unitary cam configuration, the inlet cam lobe  72 , outlet cam lobe  76  and displacement cam lobe  80  may be configured and phased to generate a pumping cycle with each rotation of the cam shaft, with each pumping cycle including a fill cycle of the pump chamber  34  that includes opening the inlet port  42  while the outlet port  52  is closed, expansion of the displacement chamber  62  while the inlet port  42  is open and then closing the inlet port  42  when the displacement chamber  62  is full of therapeutic fluid  50  while the outlet port  52  is still closed. When the displacement chamber  62  is full and the inlet port  42  and outlet port  52  are both closed, the pup chamber assembly  32  may be said to be in a pre-dispense state. 
     To carry out this fill cycle, as the cam shaft  70  is being rotated, opening the inlet port  42  includes retracting a contact surface of the inlet cam lobe  72  and associated inlet pushrod  74  to allow the resilient inlet membrane  44  to relax away from the inlet port  42 . The outlet port  52  is closed due to the extension of a contact surface of the outlet cam lobe  76  against a cam end of the outlet pushrod  78  which in turn distends the resilient outlet membrane  54  against the outlet port  52  so as to close the outlet port  52 . In this case, with the inlet port  42  in an open state, the outlet port  52  in a closed state, and the displacement chamber  62  in a minimum volume state, the pump chamber assembly may be said to be in a pre-fill stage of a pumping cycle. For the next step, the displacement chamber  62  may expanded by retracting a contact surface of the displacement cam lobe  80  and thereby retracting the associated displacement pushrod  82  to allow the resilient displacement membrane  64  to rebound and expand the effective volume of the displacement chamber  62  thus carrying out the fill cycle. For some embodiments, the amount of time for filling the displacement chamber may be about 10 seconds to about 30 seconds or more. In some cases, the displacement chamber  62  may be filled during a fill cycle over a period of about 12 seconds to about 20 seconds or more. 
     The contact surface of each of the respective cam lobes  72 ,  76 ,  80 ,  104  is that part of the cam lobe that is in contact with the respective pushrod. As such, the respective contact surfaces move around each of the cam lobes as the cam shaft is rotated. It should be noted that in some cases, each of the resilient membranes  44 ,  54 ,  64 ,  102  may be configured such that they are continually applying back pressure to the respective pushrods such that the pushrods are always exerting some pressure against the cam lobes without any lash therebetween. This same arrangement is also present for the single continuous pump membrane embodiment  124  that includes each of the resilient inlet membrane portion  44 , resilient outlet membrane portion  54 , resilient displacement membrane portion  64  and resilient vent membrane portion  102 . 
     With regard to certain use embodiments of the pump chamber assembly  32  of the medical pump system  10 , for some embodiments the inlet cam lobe  72 , outlet cam lobe  76  and displacement cam lobe  80  may be configured and phased to generate a dispense cycle that includes opening the outlet port  52  while the inlet port  42  is closed, compression of the displacement chamber  62  while the outlet port  52  is open and closing of the outlet port  52  while the inlet port  42  is still closed. In some cases the inlet cam lobe  72 , outlet cam lobe  76  and displacement cam lobe  80  may be configured and phased such that the inlet port  42  and outlet port  52  are never open at the same time during a complete rotation of the cam shaft  70 . As such, prior to the initiation of this dispense cycle, the inlet valve  42  is typically closed prior to opening of the outlet valve  52  such that the pump chamber assembly  32  is in a pre-dispense state with the dispense chamber  62  full of therapeutic fluid  50  and both the inlet valve  42  and outlet valve  52  in a closed state. For some pump assembly embodiments of the medical pump system  10  the volume and configuration of the pump chamber  34  and the lift and duration of the inlet cam lobe  72 , outlet cam lobe  76  and displacement cam lobe  80  may be configured to deliver about 2 microliters to about 10 microliters, more specifically, about 4 microliters to about 6 microliters, of therapeutic fluid  50  from the outlet port  52  for each pumping equivalent to one rotation of the cam shaft  70 . 
     With regard to a venting function wherein the vent port  100  is opened to ambient atmosphere such that the air volume  24  of the fluid reservoir  18  is thereby vented to ambient atmosphere through the open vent port  100 , in some cases the inlet cam lobe  72 , outlet cam lobe  76  and vent cam lobe  104  may be configured and phased such that the vent port  100  is open while the outlet port  52  is open and the inlet port  42  is closed. In some cases, the inlet cam lobe  72 , outlet cam lobe  76  and vent cam lobe  104  may be configured and phased such that the vent port  100  is open while the cam shaft  70  is paused after a dispense cycle and before the beginning of a fill cycle. When the vent port  100  is open to ambient atmosphere, a pressure sensor  130  disposed on the actuator assembly  14  and disposed in fluid communication with the air volume  24  of the liquid reservoir  18  is also exposed to the ambient atmosphere and is thereby configured to monitor the pressure of the ambient atmosphere and sense any changes in the ambient atmospheric pressure during this period. 
     The pressure sensor  130  may also be configured to determine a remaining volume of therapeutic fluid  50  disposed in the liquid volume  22  of the fluid reservoir  18  by measuring small pressure drops in the air volume  24  during a dispense cycle. Certain embodiments of the pressure sensor  130  may also include temperature measurement capabilities. For some embodiments, such a pressure sensor  130  may include a software controlled, high performance MEMS nano-pressure sensor having a measurement range of about 260 hPA to about 1260 hPA absolute pressure and a temperature measurement range of about −40 degrees F. to about 180 degrees F. 
     Because such pressure sensor embodiments  130  are preferably reused and not included in the limited use element of the reservoir cartridge assembly  12 , it is necessary to establish a reliable sealed fluid communication path between the pressure sensor  130  of the actuator assembly  14  and the air volume  24  of the reservoir cartridge assembly  12 . In some cases, the actuator assembly  14  may include a pressure conduit  133  which is disposed in fluid communication with the pressure sensor  130  and the air volume  24  when the actuator assembly  14  and reservoir cartridge assembly  12  are coupled together. For such an arrangement, the actuator assembly may further include a pressure conduit boot  135  which is secured in fluid communication with the pressure conduit  133  and which is configured to sealingly couple to a boot receptacle  138  as shown in  FIGS. 15 and 16 . The pressure conduit boot  135  may have a generally tapered shape and be made from a compliant elastic material that will readily and sealingly conform to the boot receptacle  138  as shown in  FIGS. 15 and 16 . The compliant elastic material of the pressure conduit boot  135  may be configured to repeatably and reliably form a seal with boot receptacle embodiments. 
     For some embodiments, the actuator assembly  14  may include a printed circuit board (PCB)  132  and the controller  88  may be operatively coupled and otherwise secured to the printed circuit board  132 . The controller  88  may include a processor  90  such as a microprocessor, memory  91  as well as any suitable components that may be useful for interfacing with the pressure sensor  130 , motor  84 , user interface embodiments such as a control button  134 , priming button  136  and the like. Such components may include electrical contacts, electrical conduits such as wiring, as well as drivers and any other machine-readable instructions stored in the memory  91  that may facilitate use of the medical pump system  10 . For some embodiments, the controller  88  may include a “system on a chip” type microprocessor, including a low power consuming high performance microprocessor that may support low energy blue tooth, near field communication and the like such as model nRF52832 manufactured by Nordic Semiconductors located in Trondheim, Norway. 
     With regard to control of the motor  84  and pump chamber assembly  32 , in some cases, the controller  88  may be configured to limit the angular velocity of the cam shaft  70  during a dispense cycle to an angular velocity that will generate a maximum flow of up to about 0.5 microliters per second through a therapeutic fluid dispense circuit of the reservoir cartridge assembly  12 . For some embodiments, the angular velocity of the cam shaft  70  may be limited during a dispense cycle to about 0.25 revolutions per minute to about 3 revolutions per minute. Such a limit on flow velocity of the therapeutic fluid  50  through the various conduits of the medical pump system  10  may be useful in maintaining the integrity of the molecular structure of certain therapeutic fluids  50 . In addition, in some instances, the controller  88  may be configured to actuate the motor  84  so as to rotate the cam shaft  70  in distinct rotation steps and take pressure measurements within the air volume  24  of the fluid reservoir  18  between the distinct rotation steps. In some cases, the motor  84  may include a direct current (DC) type electric motor that is coupled to the cam shaft  70  through the transmission  160  which provides gear reduction between rotation of the output shaft of the motor  84  and rotation of the cam shaft  70 . In some cases, the gear reduction ratio provided by the transmission  160  may be a gear reduction ratio of about 100:1 to about 250:1, more specifically, about 110:1 to about 130:1. 
     For such an arrangement, the controller  88  may be configured to generate a small pulse of electricity discharged from a capacitor which may be disposed on the PCB  132  which is communicated to the DC input of the motor  84  so as to generate a pulse of rotation in the drive shaft of the motor and a corresponding pulse of rotation, reduced by the gear reduction of the transmission, in the cam shaft  70 . In some instances, such pulses of electricity generated by the controller  88  may be about 5 milliseconds to about 50 milliseconds in duration. Such pulses of drive electricity to the motor  84  may generate rotation pulses of the cam shaft  70  of about 3 degrees to about 10 degrees, more specifically, about 5 degrees to about 7 degrees. For some embodiments, the electrical pulses may generate a corresponding rotation pulse of the cam shaft  70  of about 6 degrees such that 60 electrical pulses results in a corresponding 60 rotation pulses of the cam shaft  70  for a total of a 360 degree full rotation of the cam shaft  70 . This configuration provides a resolution in the rotation of the cam shaft  70  to the 6 degree value per pulse. In some cases, the controller may be configured to count the number of pulses or steps used per revolution of the cam shaft  70  and utilize an algorithm to adjust the duration of the electrical pulses in order to maintain a rotation per pulse of about 3 degrees to about 10 degrees, more specifically, about 5 degrees to about 7 degrees, and even more specifically, about 6 degrees. For some embodiments, the controller  88  may be configured to rotate the cam shaft  70  one full rotation over a time period of about 15 seconds to about 60 seconds, more specifically, about 25 seconds to about 35 seconds, during normal usage. 
     As discussed above, the actuator assembly  14  typically includes the pressure sensor  130  which may be disposed in fluid communication with the air volume  24  of the fluid reservoir  18 . The pressure sensor  130  is also operatively coupled to the controller  88  which may be configured to monitor pressure measurements of the pressure sensor  130  from within the air volume  24  of the fluid reservoir  18 . The controller  88  may also be configured to trigger an alarm indicating an occlusion in an outlet path  56  between the outlet port  52  and a subcutaneous delivery site  140  within the patient&#39;s body  142 , as shown in  FIG. 3 , if an unexpected pressure profile for the air volume  24  is detected by the controller  88  over a plurality of fill cycles, in some cases, if a pressure increase in the air volume  24  is detected over a plurality of consecutive dispense cycles or pumping cycles. In other cases, such an alarm might be triggered if a lack of pressure drop in the air volume  24  is detected during a fill cycle over a plurality of pumping cycles which may be indicative of a lack of flow of therapeutic fluid  50  from the liquid volume  22  during a fill cycle. Such a subcutaneous delivery site  140  may be accessed by deploying a patient port  145  that includes a hub  146  having a flexible tubular cannula  147  extending therefrom as shown in  FIG. 3 . The hub  146  may be configured to establish fluid communication between an inner lumen of the flexible tubular cannula  147  and the outlet conduit  56  of the medical pump system  10 . Any suitable commercially available patient port  145  may be used including an Ypsomed Orbit® Soft Infusion Set manufactured by Ypsomed AG located in Burgdorf, Switzerland. 
     In some cases, such an alarm may be triggered if such an unexpected pressure profile within the air chamber  24  is detected over about 2 pumping cycles to about 4 pumping cycles. In some cases an occlusion alarm may be triggered by the controller if an increase in pressure in the air chamber  24  is detected over 3 pumping cycles. In some instances, the controller  88  may also be configured to trigger an alarm indicating a pump failure if an unexpected pressure profile for the air volume  24  is detected by the controller  88  over a plurality of fill cycles. In some cases, the controller  88  may be configured to trigger a pump failure alarm if an unexpected pressure profile is detected over about 4 pumping cycles to about 6 pumping cycles. In some circumstances, the controller  88  may be configured to trigger a pump failure alarm if an unexpected pressure profile is detected over about 5 pumping cycles. 
     With regard to use of the pressure sensor  130 , the controller  88  may also be configured to determine the amount of therapeutic fluid  50  disposed in the liquid volume  22  of the fluid reservoir  18  based on a pressure measurement taken from the pressure sensor  130 . In some cases, this may be carried out by sensing a magnitude of a pressure drop within the air volume  24  during a fill cycle wherein a predetermined volume of therapeutic fluid  50  is drawn out of the liquid volume  22  and into the pump chamber  34  through the inlet port  42 . Typically, a known predetermined volume of therapeutic fluid  50  is dispensed during each pumping cycle. As the therapeutic fluid  50  is withdrawn from the liquid volume  22 , the pressure within the liquid reservoir  18  drops. The magnitude of the pressure drop during withdrawal of a predetermined volume of therapeutic fluid  50  may be dependent upon the amount of therapeutic fluid  50  remaining in the liquid reservoir  18  because the therapeutic fluid  50  has little to no compressibility and the air within the fluid reservoir  18  is highly compressible relative to the therapeutic fluid  50 . 
     As such, if the liquid volume  22  is full or nearly full of therapeutic fluid  50 , there will be a significantly higher drop in pressure within the liquid reservoir  18  during a fill cycle relative to a drop in pressure if the liquid volume  22  is nearly empty of therapeutic fluid  50  and the liquid reservoir  18  is filled mostly with compressible air. In some cases the actuator assembly  14  may also include a temperature sensor  131  which is disposed in operative communication with the controller  88 . This allows the controller  88  to monitor ambient temperature and ambient atmospheric pressure when the vent port  100  is open as well as pressure within the liquid reservoir  22  when the vent port  100  is closed. For some embodiments, the temperature sensor may be part of the pressure sensor  130 , i.e., the pressure sensor  130  also includes the temperature sensor. 
     For some embodiments, the actuator assembly  14  may also include a position sensor  144  which is operatively coupled to the motor  84  and/or the cam shaft  70 . The position sensor may further be operatively coupled to the controller  88  thus enabling the controller  88  to monitor the angular position of the motor  84  as well as the cam shaft  70 . In some cases, the position sensor  144  may include a microswitch (not shown) having an actuator lever in contact with either a drive shaft of the motor  84  and/or the cam shaft  70 . In other cases, the position sensor  144  may include a photo interrupt sensor, a hall effect sensor, a color sensor, an infrared (IR) sensor or the like. 
     As the reservoir cartridge assembly  12  is generally configured as limited use element of the medical pump system  10 , it may be useful to include components that require frequent refreshing to be included with this assembly  12 . In particular, the reservoir cartridge assembly  12  may generally include an electrical power source  148  which may be operatively coupled to the controller  88  with a conductive conduit when the reservoir cartridge assembly  12  and actuator assembly  14  are operatively coupled together. In some cases, the electrical power source  148  may include a battery. In some cases, the battery  148  may also be operatively coupled to the PCB  132  as well. Battery embodiments such as a coin cell type battery, including a CR2032 magnesium dioxide lithium battery, may be suitable for use with the medical pump system embodiments  10  in some cases. For some embodiments, the battery  148  may be secured to a portion of the reservoir cartridge assembly  12  by any suitable means and in some cases the battery  148  may be secured to a top portion of the fluid reservoir cover  95  with a double sided adhesive pad  149  that is secured on one side to the battery  148  and the opposite side to the upper side of the fluid reservoir cover  95 . For some embodiments of the battery  148 , a negative pole of the battery  148  may be electrically coupled to a first battery contact  151  and a positive pole of the battery may be electrically coupled to a second battery contact  153  as shown in  FIG. 7 , and the first battery contact  151  and second battery contact  153  may be electrically coupled to the controller  88  and/or PCB  132 . 
     With regard to patient interface features of the medical pump system  10 , for some embodiments, the actuator assembly  14  may include an indicator light  150  that is operatively coupled to the controller  88 . The indicator light  150  is configured to be viewable by the end user patient and the controller  88  may be configured to communicate a variety of signals to the indicator light  150  indicative of status information regarding the medical pump system  10 . In some cases, the indicator light  150  may include a tri-color light emitting diode. The actuator assembly  14  may also include an electronic sound emitter  152  that for some embodiments may include a piezo sounder disc that is audible to a patient and operatively coupled to the controller  88 . Any other form of sound emitter  152  may also be so used and operatively coupled to the controller  88  including voice coil speakers and the like. In some instances, the controller  88  may be configured to communicate a variety of signals to the piezo sounder disc  152  which are configured to be converted to corresponding audible signals observable by the patient end user that are indicative of status information regarding the medical pump system  10 . 
     The control button  134  may be disposed coextensively with an outside surface  154  of an outer shell  156  of the actuator assembly  14 . The control button  134  may be accessible for manual activation by a patient and operatively coupled to the controller  88  to provide an operative interface between a patient and the controller  88  and its associated control functions and programming. The priming button  136  may also operatively coupled to the controller  88  to provide priming commands to the controller  88  by a patient. In some cases, the controller  88  may be configured to initiate priming of a complete fluid path from the liquid volume  22  of the fluid reservoir  18  to the outlet conduit  56  upon activation of the priming button  136 . For some embodiments, the priming button  136  may be recessed into the outside surface  154  of the outer shell  156  of the actuator assembly  14  such that the priming button  136  is not easily accessible for manual activation by a patient without a priming tool (not shown) that may be configured to allow the patient to activate the priming button  136 . For some embodiments, the control button  134  may be used by an end user patient to directly control a pumping method of the medical pump system  10 . 
     In some cases, the controller  88 , including the memory  91  thereof, may be configured or otherwise include instructions to have certain components of the medical pump system  10  carry out certain processes based on input from the end user patient. For example, for some embodiments, once a steady state infusion rate has been generated by the controller, the patient may use the control button  134  to initiate a bolus delivery of therapeutic fluid  50  to the subcutaneous delivery site  140 . In some cases, such a bolus delivery may be instructed by a continuous press of the control button for an intermediate length duration, in some cases this might include a constant three second press of the control button  134 . Thereafter, short incremental presses of the control button  134  separated by release of the control button  134  may be used to count out the volume of the bolus to be delivered. The amount of the bolus to be delivered may then be relayed back to the patient by flashes of the indicator light  150  and/or beeps generated by the piezo sounder  152 . If these confirmation signals from the indicator light  150  and/or piezo sounder  152  are correct, the patient may then confirm the bolus instruction with a long continuous press of the control button  134 , for example, a six second continuous press of the control button  134 . Thus, the controller  88  may be configured to deliver a desired volume of bolus delivery using only a single controller button  134  and three types of button presses, including the instantaneous incremental press followed by an immediate release of the control button  134 , a continuous press and hold of intermediate length or duration, including the 3 second continuous press and a continuous press and hold of a long duration of about 6 seconds. In some instances, it may be useful for the duration of the long continuous press of the control button  134  to be twice or more that of the intermediate continuous press in order for the patient to be able to easily distinguish between these two types of button presses. 
     In some cases, the controller  88  and associated components thereof may be configured such that an in progress bolus delivery may be canceled by a long duration continuous press of the control button  134 . In addition, the controller  88  and associated components thereof may be configured such that an in progress controlled infusion rate, such as a basal rate, delivery may be canceled by a long duration continuous press of the control button  134 . In addition, during normal operation of some medical pump system embodiments  10 , a status check may be initiated by the patient by a single short press of the control button  134  followed by immediate release. The short press and release of the control button  134  may also be used to acknowledge any alerts being transmitted by the controller  88  through the piezo sounder  152  and/or indicator light  150 . 
     For some embodiments, the actuator assembly  14  may include an optional transmission  160  which is operatively coupled between the cam assembly  68  and the motor  84 . For some motor embodiments, such a transmission  160  may not be necessary. However, for some motor embodiments  84 , it may be useful to include such a transmission  160  in order to better control rotation of the cam shaft  70  with a suitable gear reduction ratio. In some cases, the transmission  160  may include a planetary gear box or the like. 
     Some embodiments of the actuator assembly  14  may include an actuator chassis  162  and the cam assembly  68 , motor  84  and transmission  160  may be disposed on the actuator chassis  162 . The actuator assembly  14  may also include a latch post  164  secured to and extending from a bottom surface of the actuator chassis as shown in  FIG. 7 . The reservoir cartridge assembly  12  may in turn include a latch spring  166  that is disposed on the reservoir base  94  of the reservoir cartridge assembly  12  as shown in  FIGS. 7 and 17 . The latch spring  166  may be configured to latch onto a groove or slot  168  the latch post  164 , as shown in  FIG. 5 , to prevent separation of the actuator assembly  14  from the reservoir cartridge assembly  12  after they have been operatively coupled together. In some instances, the latch spring  166  may be configured to be permanently disabled after being disengaged from a latch post  164  to prevent multiple uses of the latch spring  166 . As such, the latch mechanism  16  may include a disabling feature  167 , shown in  FIG. 17 , which the latch spring  166  is spring biased against and which includes a ramped end and a flat end. When the latch spring  166  is disengaged by translating the latch spring  166  to the left with the priming tool or any other suitable instrument, the biased end  169  of the latch spring  166  slides up and over the ramp end and elastically snaps into engagement behind the flat end with the latch spring in a position where it no longer is able to engage the groove  168  of the latch post  164 , thus disabling the latch mechanism embodiment  16 . The disabling feature  167  shown in  FIG. 17  is an exemplary embodiment and any other suitably configured mechanism may also be used. 
     With regard to coupling the reservoir cartridge assembly  12  to the actuator assembly  14 , in some instances, the actuator chassis  162  and the reservoir base  94  may include a mutual alignment feature  172  as shown in  FIG. 9  which may be configured to be operatively and releasably coupled between the actuator chassis  162  and the reservoir base  94  that prevents relative lateral displacement between the actuator chassis  162  and the reservoir base  94 . In some cases, the alignment feature  172  may include an alignment slot  174  secured in fixed relation to reservoir base  94  and an alignment rib  176  which is secured in fixed relation to the actuator chassis  162  with the alignment rib  176  being configured to fit tightly within the alignment slot  174 . The arrangement could also be reversed with the alignment slot  174  disposed on the actuator chassis  162  and the alignment rib  176  disposed on the reservoir base  94 . Any other suitable type of alignment feature  172  may be used as well in order to limit or prevent any relative lateral displacement between the actuator chassis  162  and reservoir base  94  during rotation of the cam assembly  68  against the pushrods of the pump assembly. 
     For some embodiments, the actuator assembly  14  may also include the outer shell  156  which may be a smooth continuous layer of rigid material which is disposed over and protects all of the components of the actuator assembly  14  from environmental elements, including moisture. As such, in some cases, an outer shell seal  158  may be disposed about an outer perimeter  96  of the reservoir base  94 , as shown in  FIGS. 10 and 11 , and be sized and configured to seal to an inside surface  157  of the outer shell  156  when the actuator assembly  14  is coupled to the reservoir cartridge assembly  12 . In some cases, the outer shell seal  156  may include a flexible elastomer with a double lip transverse cross section as shown in  FIGS. 10 and 11 . The contact parameters between the inside surface  157  of the outer shell  156  and the outer shell seal  158  may be configured, in some instances, to provide a level IP24 rated seal therebetween. 
     The reservoir cartridge assembly  12  may include a fill port  174  to facilitate manual filling of the liquid volume  22  of the fluid reservoir  18  as shown in  FIG. 18  once the reservoir cartridge assembly  12  has been coupled to the actuator assembly  14 . For some embodiments, the fill port  174  may include a fill septum  176  which has an inner surface  178 , an outer surface  180  and which is disposed within a fill septum cavity  181 . The fill septum cavity  181  may include an open portion  182  disposed adjacent the inner surface  178  of the fill septum  176 . The open portion  182  may also be disposed in fluid communication with a fill passage  184 . The fill passage  184  may in turn be disposed in fluid communication between the fill septum cavity  181  and the liquid volume  22  of the fluid reservoir  18 . A patient may generally use the fill port  174  by filling an appropriately configured syringe with a desired therapeutic fluid  50  and inserting the hypodermic needle of the syringe (not shown) through the fill septum  176  and into the open portion  182  of the fill septum cavity  181  with a distal port of the hypodermic needle in fluid communication with the open portion  182  of the fill septum cavity  181 . The syringe may then be emptied into the open portion  182  of the fill septum cavity  181  with the therapeutic fluid  50  so delivered flowing through the fill passage  184  into the liquid volume  22 . In some instances, the open portion  182  may include a needle stop surface  186  formed by an inner surface of the fill septum cavity  181  disposed opposite the inner surface  178  of the fill septum  176 . The needle stop surface  186  may be configured and positioned to prevent unwanted penetration of the hypodermic needle into fragile components of the medical pump system  10 . For some embodiment, the fill septum  176  may include an elastic polymer such as polyurethane, silicone or the like. 
     Once the liquid volume  22  of the fluid reservoir  18  of the medical pump system  10  has been filled, the patient will generally attach the medical pump system  10  to a desired position on their body. Some embodiments of the medical pump system  10  discussed above may include an optional mount bracket  188  that may be used to releasably secure the coupled actuator assembly  14  and reservoir cartridge assembly  12  to an outer surface of the patient&#39;s skin  143  in a desired location. Referring to  FIGS. 2-4 , the mount bracket  188  may include a bracket body  190  having an adhesive layer  192  disposed on a bottom surface of an adhesive pad  194  that is secured to the bracket body  190 . Typically, the adhesive surface of the adhesive layer  192  will be covered by a peel off layer that maintains the integrity of the adhesive surface until ready for use. The bracket body  190  may have an outer contour that generally matches an outer contour of the perimeter of the outer shell  156  of the actuator assembly  14 . The bracket body  190  also includes a plurality of mount receptacles  196  that are configured to receive corresponding mount tabs  198  disposed on the outer perimeter of the outer shell  156  (see also  FIG. 7 ). 
     One of the mount receptacles  196  may include a flexible bail  200  that may have a resilient flexibility that allows a mating mount tab  198  of the outer shell  156  to be snapped into place with an opening of the flexible bail  200  mechanically capturing the mating mount tab  198 . Once the end user patient is ready to remove the actuator assembly  14  from the mount bracket  188 , the flexible bail  200  may be elastically flexed outwardly away from the outer shell  156  so as to disengage the flexible bail  200  from the mating mount tab  198  disposed therein thereby releasing the actuator assembly  14  and reservoir cartridge assembly  12  coupled thereto from the mount bracket  188 . The flexible bail  200  is elastically deformed and thus reusable if desired. For some mount bracket embodiments  188 , the adhesive pad  194  may have a length of about 2.5 inches to about 3 inches, a width of about 2 inches to about 2.5 inches and a thickness of about 0.2 inches to about 0.5 inches. The adhesive surface  192  may include any adhesive suitable for skin contact including acrylate type adhesives or the like. 
     The coupled actuator assembly  14  and reservoir cartridge assembly  12  may also be attached to the patient&#39;s body  142  in other ways. For example, in some cases, a flexible polymer layer  141  separate from the medical pump system  10  may be used. As such, for some kit embodiments that include medical pump system embodiments  10 , such a kit may also include an optional flexible polymer layer or patch  141  shown schematically in  FIG. 3  which is sized to fit over the actuator assembly  14  and assembled medical pump system  10  as a whole. The flexible polymer patch  141  may include an adhesive backed perimeter portion which is configured to be releasably secured to a patient&#39;s skin  143 . For some embodiments, the flexible polymer patch  141  may have at least one vent hole disposed therethrough. For such an application, the flexible polymer patch  141  may be disposed over the medical pump system  10  against the patient&#39;s skin  143  and the adhesive backed perimeter portion thereof secured to the patient&#39;s skin  143  creating a pouch against the patient&#39;s skin  143  in which the medical pump system  10  may be disposed. Once the medical pump system  10  needs to be removed or otherwise accessed, the flexible patch would be removed from the patient&#39;s skin  143  and a new flexible patch  141  used to reattach the medical pump system  10  to the patient. Typically, the flexible polymer patch  141  would be made of a clear flexible material that would permit operation of the control button  134  and priming button  136  and would also transmit any audio or visual signals therethrough. 
     In some cases, a patient may initiate use of medical pump system embodiments  10  discussed herein by coupling the reservoir cartridge assembly  12  to the actuator assembly  14  to form the medical pump system  10 . In some cases, the coupling of the reservoir cartridge assembly  12  to the actuator assembly  14  may be detected by the controller  88  by the controller  88  which detects electrical power being supplied to the controller  88 . The controller  88  may then initiate a power-on-self-test once the controller  88  has detected electrical power being supplied to the controller  88 . In addition, a time point zero may be stored into a memory  91  of the controller  88  and a power source voltage check initiated by the controller  88 . In some instances, at this stage, the controller  88  may be configured to perform one complete rotation of the cam assembly  68  or cam shaft  70  of the actuator assembly  14  with the cam shaft  70  coming to a stop in an angular position wherein the inlet port  42  of the pump chamber assembly  32  of the reservoir cartridge assembly  12  is closed and the vent port  100  of the pump chamber assembly  32  of the reservoir cartridge assembly  12  is open to the ambient atmosphere. 
     Thereafter, the liquid volume  22  of a fluid reservoir  18  of the reservoir cartridge assembly  12  may be manually filled with the therapeutic fluid  50  while venting air from the air volume  24  disposed adjacent the liquid volume  22 . The liquid volume  22  may be filled through the fill port  174  with a syringe or other suitable source of desired therapeutic fluid  50 . As discussed above, the therapeutic fluid  50  injected into the fill port  174  flows through the fill passage  184  and into the liquid volume  22  bounded by a fluid cavity molded into the reservoir base  94  and the flexible membrane  28  sealed thereto. In some cases, the flexible membrane  28  may be pre-molded or otherwise form fitted to the fluid cavity molded into the reservoir base  94  to reduce or eliminate any air pockets in the liquid volume  22  when the liquid volume is empty as shown in  FIG. 19A . As therapeutic fluid  50  flows into the liquid volume space, the flexible membrane  28  begins to distend and separate from the fluid cavity surface of the reservoir base  94  as the incoming therapeutic fluid begins to displace the flexible membrane as illustrated by the partially filled liquid volume shown in  FIG. 19B . The liquid volume  22  may continue to be filled through the fill port  174  until the liquid volume  22  of the fluid reservoir  18  is completely filled with the flexible membrane  28  being pressed up against or adjacent to the fluid reservoir cover  95  as shown in  FIG. 19C . For some embodiments, the fluid reservoir cover  95  as well as the reservoir base  94  may be formed from clear polymer materials in order for a patient to be able to visualize the fill level within the liquid volume  22  of the fluid reservoir  18 . 
     The outlet conduit  56  of the pump chamber assembly  32  may be primed by activating the priming button  136  of the actuator assembly  14  and the medical pump system  10  releasably secured to the patient. In some instances, releasably securing the medical pump system  10  to the patient may include removing a backing of the adhesive pad  194  of the mount bracket  188  of the medical pump system embodiment  10 , applying the adhesive surface  192  of the adhesive pad  194  to the patient&#39;s skin  143  in a suitable location and releasably securing the actuator assembly  14  and reservoir cartridge assembly  12  of the medical pump system  10  to the mount bracket  188 . In other cases, releasably securing the medical pump system  10  to the patient may include disposing a flexible polymer layer over the medical pump system  10  and sealing the perimeter of the flexible polymer layer to the patient&#39;s skin  143  around the medical pump system  10  as discussed above. Once the medical pump system  10  is so secured, the outlet conduit  56  of the pump chamber assembly  32  may be disposed in fluid communication with a subcutaneous delivery site  140  within the patient&#39;s body  142 . A controlled rate of infusion, such as a basal rate, of the therapeutic fluid  50  may then be delivered to the subcutaneous delivery site  140  of the patient by performing sequential pumping cycles of the medical pump system  10  carried out according to a predetermined delivery protocol. 
     In some instances, performing such a pumping cycle may include performing a fill cycle of the cam assembly  68  followed by performing a dispense cycle of the cam assembly  68  by rotation of the cam shaft  70 . In some embodiments, performing a fill cycle by rotation of the cam shaft  70  may include disposing the inlet cam lobe  72  in a retracted position with an inlet port  42  of the pump chamber assembly  32  in an open position as shown in  FIG. 14A . The fill cycle may also include disposing the outlet cam lobe  76  in an extended position with an outlet port  52  of the pump chamber assembly  32  in a closed position and disposing the displacement cam lobe  80  in an extended position. Thereafter, with the inlet port  42  open and the outlet port  52  closed, the displacement cam lobe  80  may be retracted as indicated by the arrow  202  in  FIG. 14A  so as to expand the displacement chamber  62  and draw therapeutic fluid  50  through the inlet port  42  and into the expanding displacement chamber  62  as indicated by arrow  204  in  FIG. 14A  until the displacement cam lobe  80  is fully retracted and the displacement chamber  62  is full of therapeutic fluid  50  as shown in  FIG. 14B . During this fill cycle, the controller  88  may be configured to determine a fill level of the liquid volume  22  of the fluid reservoir  18  by monitoring a pressure drop within the air volume  24  of the fluid reservoir  18  with the controller  88  during the fill cycle. In addition, embodiments of the fill cycle may terminate by extending the inlet cam lobe  72  until the inlet port  42  is closed while maintaining the displacement cam lobe  80  in a retracted position and with the outlet port  52  closed as shown in  FIG. 14B . 
     In some cases, performing the dispense cycle by rotation of the cam shaft  70  may include retracting the outlet cam lobe  76  and opening the outlet port  52  while the displacement chamber  62  is full of therapeutic fluid  50  and while the inlet port  42  is closed. The dispense cycle may also include extending the displacement cam lobe  80  as indicated by arrow  205  in  FIG. 14B  and reducing a volume of the displacement chamber  62  and dispensing the therapeutic fluid  50  disposed therein out of the outlet port  52  as shown by arrow  206  while the inlet port  42  is closed and the outlet port  52  is open. The dispense cycle may also include opening the vent port  100  of the pump chamber assembly  32  and venting the air volume  24  of the fluid reservoir  18  to an ambient atmosphere as indicated by arrow  107  during the dispense cycle. The dispense cycle, in some instances, may also include maintaining the vent port  100  in an open state and venting the air volume  24  of the fluid reservoir  18  to the ambient atmosphere while waiting for a subsequent dispense cycle so as to monitor ambient pressure and detect any unexpected ambient pressure profiles. During both the fill cycle and dispense cycle, rotation of the cam shaft  70  may be monitored by the controller  88  using the position sensor  144 . 
     For some embodiments and delivery of certain therapeutic fluids  50 , delivering a controlled rate of infusion, such as a basal rate, of the therapeutic fluid  50  may include delivering about 5 microliters to about 15 microliters of therapeutic fluid  50  per hour to the subcutaneous delivery site  140 . For some embodiments, the fluid reservoir  18  may have a volume capacity of about 2 ml to about 5 ml, more specifically, about 2.8 ml to about 3.2 ml. Once the therapeutic fluid  18  disposed within the liquid volume  22  of the fluid reservoir  18  is used up, or close to being used up, an alarm signal may be triggered by the controller  88 . In addition, with regard to a time limit for the reservoir cartridge assembly  12  programmed into the controller memory  91 , expiry of the reservoir cartridge assembly  12  may indicated and triggered after about 60 hours of use to about 100 hours of use by activating an alarm signal with the controller  88 . Such an alarm signal will be observable by the patient either visually or audibly. 
     In some cases, certain components or subassemblies of the medical pump system embodiments  10  discussed herein may be useful separately or as part of another pump system embodiment. Referring to  FIG. 20 , a schematic representation of a pump assembly embodiment  210  for medical use is shown that includes components of the medical pump system embodiments  10  discussed above and that may perform the same functions in the same manner as discussed above. The pump assembly embodiment  210  may include the pump chamber assembly  32  including the pump chamber  34  having an interior volume  36  which is at least partially bounded by the pump housing  38 . The pump chamber assembly  32  may also include the inlet port  42  which is in fluid communication with the interior volume  36 . The pump chamber assembly  32  may also include the resilient inlet membrane  44  which is disposed adjacent the inlet port  42 , which is spaced from the inlet port  42  when in a relaxed state, and which is sufficiently distendable towards the inlet port  42  to seal the inlet port  42  when in a compressed state. The pump chamber assembly  32  may also include the outlet port  52  in fluid communication with the interior volume  36  and the resilient outlet membrane  54  which is disposed adjacent the outlet port  52 , which is spaced from the outlet port  52  when in a relaxed state, and which is sufficiently distendable towards the outlet port  52  to seal the outlet port  52  in a compressed state. The displacement chamber  62  may also be disposed within the interior volume  36  and the resilient displacement membrane  64  is disposed adjacent the displacement chamber  62 , which forms at least a portion of a boundary of the displacement chamber  62 , which is sufficiently inwardly distendable from a relaxed state to reduce the volume of the displacement chamber  62  when in a compressed state. The resilient displacement membrane  64  may also be sufficiently resilient to increase the volume of the displacement chamber  62  when released from the compressed state. 
     The pump assembly  210  may also include an actuator assembly embodiment  14  having the cam assembly  68  with the cam shaft  70  that includes the inlet cam lobe  72  which is operatively coupled to the resilient inlet membrane  44 , the outlet cam lobe  76  which is operatively coupled to the resilient outlet membrane  54 , and the displacement cam lobe  80  which is operatively coupled to the resilient displacement membrane  64 . The actuator assembly  14  may also include the motor  84  operatively coupled to the cam assembly  68  and the controller  88  operatively coupled to the motor  84 . The power source  148  such as a battery may also be operatively coupled to the controller  88 . All of the components of the pump assembly embodiment  210  shown in  FIG. 20  may function in the same manner as discussed herein with regard to other pump system embodiments  10 . In addition, for some embodiments, the inlet cam lobe  72  may be operatively coupled to the inlet valve assembly  75 , the outlet cam lobe  76  may be operatively coupled to the outlet valve assembly  79  as well as the displacement cam lobe  80  being operatively coupled to the displacement chamber and its associated components including the displacement pushrod  82 . 
     Proper compliance with regard to use of medical devices may typically be achieved by providing instructions for use (IFU) to a patient or treating physician. Such IFUs often include an overwhelming amount of information and warnings forewarning against negative consequences. Due to the patient&#39;s challenge in becoming acceptably knowledgeable, educators and physicians are often required to provide a personal level of education and training support for treatments being administered. This practice may, in some circumstances, create a financial burden to the patient end user and also result in inconsistent success rates with regard to compliance due to the lack of consistency in training methods. 
     Devices that require user input in order to complete a specific function related to the therapy being administered may have reduced effectiveness if used the patient end user does not fully understand how to complete the specific function correctly. For instance, use of an ambulatory insulin infusion pump intended for use by an end user patient with diabetes that does not have any professional medical training typically requires the end user to select a quantity of insulin to be infused based on the current blood sugar level or meal they plan to consume which may be fairly complicated in some instances. As such, it may be desirable to provide a device and/or method for such an end user to engage in hands on training of the particular device they will be using without the risk of a potentially costly mistake in order to gain familiarity and confidence prior to actual therapeutic use. 
     As such, certain medical devices, such as medical pump systems  10  or components thereof may be supplied with an attachable training module or cartridge  220  that may be combined to form a medical pump training system  222  as schematically illustrated in  FIG. 21 . Such a medical pump training system  222  may enable the end user patient to simulate the use of the medical device in a safe environment without the risk of wasted medical materials or equipment. The schematic overview of the embodiment of the medical pump training system  222  shown in  FIG. 1  includes a dashed line which indicates a coupling interface between the actuator assembly  14 ′ and the training cartridge  220  of the medical pump training system  222 , and the various components thereof. The coupling interface represents the physical point of separation between the respective components of each of the actuator assembly embodiment  14 ′ and training cartridge  220  that interface with each other when the actuator assembly  14 ′ and training cartridge  220  are coupled together. The interconnecting lines between the various schematic components of  FIG. 21  may include any type of suitable conduit that may be useful for operatively interconnecting the components such as information conducting conduits, power conducting conduits or the like including conductive wires, optical fibers, wireless connectivity etc. In general, the actuator assembly embodiment  14 ′ may include any or all of the components of the actuator assembly  14  discussed above. The actuator assembly embodiment  14 ′ in  FIG. 21  is shown without any of the cam lobes  72 ,  76 ,  80  or  104  for clarity of illustration and because these components of the actuator assembly may not typically have any counterpart components in the training cartridge  220  to interface with. Likewise, the motor  84  and transmission  160  of the actuator assembly embodiment  14 ′ are not shown for purposes of clarity of illustration. 
     In the case of medical pump embodiments, such as insulin pump embodiments, such a training cartridge  220  may be installed in place of the reservoir cartridge assembly  12  (reservoir) that includes or could include therapeutic materials, thereby eliminating the potential risk of over infusion of a drug, such as insulin, and allow the end user to be accustomed to the associated device inputs, outputs, interface protocols etc. For some embodiments, such a training cartridge  220  may also allow the therapeutic device, such as the actuator assembly embodiments  14 ′ to receive updates to software stored in the memory  91 ,  91 ′ of the respective controllers  88 ,  88 ′, or customizations in firmware, ensuring the device  14 ′ is in a safe mode that minimizes the risk to the user. This type of arrangement may be particularly useful for medical pump system embodiments  10  that include a durable element and a low use or disposable element, such as the actuator assembly embodiments  14  and reservoir cartridge assembly embodiments  12  discussed above. 
     With regard to medical pump systems  10  as discussed herein, as well as others, suitable training cartridge embodiments  220  may include certain elements that are typically included in a therapeutic cartridge in order to enable functioning of the system as a whole. In particular, some embodiments of the training cartridge  220  for use with the actuator assembly embodiments  14 ′ discussed herein may be used in place of the reservoir cartridge assembly embodiments  12  discussed herein. The training cartridge  220  may include an element that provides power to a functioning actuator assembly  14 ′ and may be configured to latch onto the actuator assembly  14 ′ in a similar fashion to that of the reservoir cartridge assemblies  12  (disposable) enabling the end user to exercise the physical elements of the medical pump system embodiments  10  and become familiar/comfortable with them. 
     In some cases, it may be desirable for the latch spring  166 ′ of the training cartridge  220 , as shown in  FIG. 21 , to be reusable so that the training cartridge  220  may be used multiple times for multiple training sessions. As such, the training cartridge  220  may be configured to be reused and reattached while the therapeutic reservoir cartridge assembly embodiments  12  discussed herein are generally intended for single use and have a single use release latch  166 . As such, the latch spring  166 ′ may be configured to not include the disabling feature  167  that is part of the latch mechanism  16  discussed above or may include any other suitable features or lack thereof that configures the latch mechanism of the training cartridge  220  to be reusable. In addition, for some embodiments of the training cartridge  220 , the portion of the latch mechanism housed in the training cartridge  220 , may include an electro-mechanical structure that is configured to be releasably secured to the latch post  164 , and controllable by the controller  88 ′ in order to be released from the latch post  164 . 
     The training cartridge embodiments  220  may also have a means for the mating actuator assembly  14 ′ to differentiate the training cartridge  220  from the therapeutic reservoir cartridge assembly embodiments  12  so the actuator assembly  14 ′ configures itself to operate in a training mode. In some cases, when the actuator assembly  14 ′ is coupled to the training cartridge  220 , the controller  88  may be disposed in operative communication with the controller  88 ′, and the controller  88 ′ may be configured to identify the training cartridge  220  by communicating an identification signal to the controller  88 . In addition, other techniques for establishing such differentiation may include providing a certain identifying feature or features  224  on the training cartridge  220  that may be read or otherwise interpreted by an optional reader  226  that may be operatively coupled to the controller  88 . In some cases, the training cartridge  220  may also include an optional training module controller  88 ′ that may be operatively coupled to power source  148  as well as the controller  88  of the actuator assembly  14 ′. Such a training cartridge controller  88 ′ may be configured to communicate with the controller  88  of the actuator assembly  14 ′ and provide identifying information, training programs and the like. 
     Regarding examples of identifying features  224 , some embodiments of the training cartridge  220  may include an identifying feature  224  including NFC tag, a 2D barcode on training cartridge with read camera  226  on actuator assembly  14 ′, a resistive label disposed on the training cartridge  220  with corresponding contacts on actuator assembly  14 ′, a mechanical feature disposed on the training cartridge  220  that actuates a switch  226  on the actuator assembly  14 ′ or a magnet on the training cartridge and hall effect sensor  226  on actuator assembly  14 ′. 
     In use, for some embodiments, a training mode may provide specific user functions and disengage critical alarms caused from failure detections on the actuator assembly  14 ′ (e.g., occlusion detection, low insulin, pump malfunction). The actuator assembly  14 ′ may, in some cases, wirelessly connect (BLE) to a remote mobile device  228 , such as a smart phone or the like with supporting application as shown in  FIG. 21 . In some cases, a training mode of the actuator assembly  14 ′ may unlock a training section of the phone application. For some embodiments, the remote mobile device  228  may be configured to provide real time guidance and feedback to a user of the device based on a status of a condition being monitored by the controller  88 , or in some cases, controller  88 ′. In some instances, the remote mobile device  228  may be configured to communicate status data regarding conditions being monitored by the controller  88 , or in some cases controller  88 ′, to a cloud data management system through a wireless connection between the remote mobile device  228  and the cloud data management system (not shown). Such a training application for a remote mobile device  228  or the like may include providing tutorials, videos, and/or a dashboard providing additional information on actuator assembly features. The training mode of the actuator assembly  14 ′ may also include the ability to switch from training mode to operation mode based on pump feedback driven by the training cartridge  220  being installed. A connection to a data portal or the like in order to upload status and provide real time tracking and support of the actuator assembly  14 ′ or any other component of the medical pump system  10  from an administrative account. In some cases, support analysis of user training sessions may be communicated to the controller  88  in order to ensure that the medical pump system  10  or components thereof are being utilized in a safe and useful manner. 
     Referring to  FIGS. 21-23 , a medical pump training system  222  is shown that may include the actuator assembly  14 ′ having an actuator chassis  162  and the controller  88  secured to the actuator chassis  162 . The medical pump training system  222  may also include the training cartridge  220  having a cartridge housing  221  which is configured to releasably couple to the actuator assembly  14 ′ and which includes the identifying feature  224  that is configured to be operatively coupled to the controller  88  of the actuator assembly  14 ′ and provide information to the controller  88  identifying the training cartridge  220  as a non-therapeutic cartridge. In some cases, the identifying feature  224  may be operatively coupled to the controller  88  by means of the reader  226  which may be operatively coupled to both the controller  88  and the identifying feature  224 . 
     In some cases, a memory  91  of the controller  88  may include instructions, which may include machine readable instructions, to initiate a training program for a patient once the controller  88  identifies the training cartridge  220  by receiving the information from the identifying feature  224 . As discussed above, suitable examples of identifying feature embodiments  224  may include an NFC tag. The identifying feature  224  may also include a 2D barcode disposed on the training cartridge  220  and the actuator assembly  14 ′ may further include a read camera  226  which is configured to read the 2D barcode. In some instances, the identifying feature  224  may be a resistive label and in such cases the actuator assembly  14 ′ may have corresponding electrical contacts that are configured to operatively couple to the resistive label such that the controller  88  will be configured to determine the resistance of the resistive label and identify the training cartridge  220 . For some embodiments, the identifying feature  224  may include a mechanical feature and the actuator assembly  14  further comprises a switch and the mechanical feature is configured to actuate the switch on the actuator assembly  14 ′. In some cases, the identifying feature  224  may include a magnet disposed on the training cartridge  220  and the actuator assembly  14 ′ may have a corresponding a hall effect sensor which is configured to be operatively coupled to the magnet to enable the controller  88  which is operatively coupled to the hall effect sensor to identify the training cartridge  220 . As noted above, it may be desirable for the training cartridge  220  to be reusable. As such, in some instances, the cartridge housing  221  may further include a reusable latch spring  166 ′ that is configured to releasably couple to a latch post  164  which is secured in fixed relation to the actuator assembly  14 ′. 
     Some embodiments of a training cartridge  220  for a medical pump system  10  may include the cartridge housing  221  that is configured to couple to an actuator assembly  14 ′ of the medical pump system  10  and the identifying feature  224  disposed on the cartridge housing  221  that is configured to be operatively coupled to a controller  88  of the actuator assembly  14 ′ and provide information to the controller  88  identifying the training cartridge  220 . For some such training cartridge embodiments  220 , the cartridge housing  221  may further include the reusable latch spring  166 ′ that is configured to releasably couple to the latch post  164  of the actuator assembly  14 ′. 
     Referring to  FIG. 24 , a method  300  for operating embodiments of the medical pump system  10  is shown. When describing the method  300 , reference is made to elements of the actuator assembly  14 ′ described herein. At step  302 , a cartridge is coupled to the actuator assembly  14 , for example. In some cases, the cartridge being so coupled may be either a reservoir cartridge assembly embodiment  12  or a training cartridge  220 . In doing so, power (voltage, current, etc.), data and control signals, and/or therapeutic fluid  50  or other matter are capable of exchange between the actuator assembly  14 ′ and the cartridge. At decision diamond  304 , a type of cartridge is determined. In some embodiments, the type of cartridge is determined by hardware, for example, one or more interfaces, input/output devices, or the like of the actuator assembly  14 ′. In other embodiments, the type of cartridge is determined by software, for example, stored in a computer memory at the cartridge, the actuator assembly  14 ′, or an external computer location, such as a remote computer, a cloud computing environment, and so on that communicates with the actuator assembly  14 ′ and/or cartridge to identify the type of cartridge. In other embodiments, the cartridge is identified by a combination of hardware and software. 
     If at decision diamond  304 , a reservoir cartridge assembly  12  is identified as coupled to the actuator assembly  14 ′, then the method  300  proceeds to step  306  where the medical pump system  10  is in an operation mode, for example, capable of use for delivery of a therapeutic fluid  50  to a patient end user. At step  308 , the latch mechanism  16  as part of a coupling mechanism between the reservoir cartridge assembly  12  and the actuator assembly  14 ′, for example, the latch spring  166  shown in  FIGS. 1 and 8 , operates to permit a single use of the reservoir cartridge assembly  12  and prohibits a subsequent coupling of the same reservoir cartridge assembly  12  to the actuator assembly  14 ′. If at decision diamond  304 , a training cartridge  220  is identified as coupled to the actuator assembly  14 ′, then the method  300  proceeds to step  310 , where the medical pump is in a training mode, for example, capable of training a user. At step  312 , the latch  16  as part of a coupling mechanism between the training cartridge  220  and the actuator assembly  14 , for example, the latch spring  166 ′ shown in  FIG. 21 , operates to permit multiple uses of the training cartridge  220 . 
     At step  214 , the medical pump system  10  can connect wirelessly, for example, using BLE or other wireless interface, to a remote mobile device, such as a smartphone  228  or other computer having display or other input/output devices for permitting a trainee or other user to communicate with the medical pump system  10 . When the training mode is determined at step  310 , at step  314  the remote mobile device  228  may include an application that is activated, or unlocked, for example, in response to a receipt of a signal comprising data from the controller  88 ′ of the training module  220 . Returning to decision diamond  304 , although a decision is made here whether the medical pump system  10  is in an operation mode or a training mode, some embodiments may include the ability to switch from the training mode to the operation mode based on pump feedback or other data driven by the training module  220 . 
     Embodiments illustratively described herein suitably may be practiced in the absence of any element(s) not specifically disclosed herein. Thus, for example, in each instance herein any of the terms “comprising,” “consisting essentially of,” and “consisting of” may be replaced with either of the other two terms. The terms and expressions which have been employed are used as terms of description and not of limitation and use of such terms and expressions do not exclude any equivalents of the features shown and described or portions thereof, and various modifications are possible. The term “a” or “an” can refer to one of or a plurality of the elements it modifies (e.g., “a reagent” can mean one or more reagents) unless it is contextually clear either one of the elements or more than one of the elements is described. Thus, it should be understood that although embodiments have been specifically disclosed by representative embodiments and optional features, modification and variation of the concepts herein disclosed may be resorted to by those skilled in the art, and such modifications and variations are considered within the scope of this disclosure. 
     With regard to the above detailed description, like reference numerals used therein refer to like elements that may have the same or similar dimensions, materials and configurations. While particular forms of embodiments have been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the embodiments of the invention. Accordingly, it is not intended that the invention be limited by the forgoing detailed description.