Patent ID: 12194276

DETAILED DESCRIPTION

The present technology comprises infusion devices configured to be adhered to the user's skin above the delivery site (sometimes referred to as “patch pumps”). The infusion devices include a reservoir configured to receive and contain a medicament, a motor, and an insertion assembly having a cannula that is to be operatively connected to the reservoir. After applying the device to the skin, the user activates the insertion assembly to insert the cannula subcutaneously. Often times this insertion step requires the user to manually press or pull a trigger on the device, which can be burdensome for the patient. Disclosed herein are infusion devices configured for remotely triggered cannula insertion (e.g., triggered by a computing device that is separate from but communicatively coupled to an infusion device). As described in greater detail below, the infusion devices herein are configured to be communicatively coupled to a remote controller that, at the user's command, sends instructions to the infusion device that causes the insertion assembly to deploy the cannula. In some embodiments, the instructions cause a predetermined rotation of the motor, and the infusion device includes a trigger assembly that leverages the motor's rotations to move or allow movement of the insertion assembly to a cannula-release position. In any case, the infusion devices of the present technology enable cannula insertion via remote control, which can be more convenient for the user than conventional manual triggers.

FIGS.1A and1Bshow top and bottom sides, respectively, of an infusion device100in accordance with several embodiments of the present technology. As previously mentioned, the bottom side100bof the device100is configured to be adhered to the user's skin with the top side100afacing away from the user. The device100includes a durable assembly200and a disposable assembly300, each having respective housings202and302. The durable assembly200and disposable assembly300are disposed on an adhesive pad102with adhesive backing104for securing to the user's skin. The bottom side100bof the device100may also include a pull-before-use plug (PBUP)108and a fill port106.

The device100may be used in conjunction with a wide variety of remote controllers. The remote controller, for example, can be a device-specific controller, a mobile phone, a tablet, etc. Such remote controllers may be used, for example, to allow the user to transmit instructions to the durable assembly200or otherwise facilitate communication between durable assembly200and the user (e.g., an alarm condition message or other message concerning the conditions of device100). In some embodiments, the remote controller is configured to send instructions to and/or receive instructions from the disposable assembly300.

The remote controller may be configured to facilitate one, some, or all of the following operations:turning the remote controller on or off;associating (or “assigning”) the remote controller to the durable assembly200;obtaining status information such as medicament level, battery charge level, and/or alarm conditions;silencing the durable assembly's alarm;selecting options that may be associated with the durable assembly's alarm such as type of alarm (audible, palpable, visible or combinations thereof) and strength/volume of alarm;connecting the remote controller to a computer to, for example, update the remote controller or durable assembly firmware, load and delete delivery profiles stored in the durable assembly200or remote controller, and otherwise reprogram the durable assembly200and/or the remote controller;selecting medicament options such as medicament concentrations;selecting a stored medicament delivery profile;increasing and decreasing medicament dose rate;triggering cannula insertion;initiating medicament delivery;pausing a dispensing operation;and/or other processes.

A user may pause delivery in order to remove or replace a user-applied structure (e.g., a disposable assembly), adjust for a current or anticipated changed body condition (e.g., low glucose, vigorous exercise), follow a physician's suggestion, or disconnect the durable assembly200from the body for any other reason.

In some embodiments, the remote controller is configured to generate an indicator, based on information from a microprocessor of the durable assembly200, that is indicative of, for instance, the amount of time remaining in the current dispensing program, the amount of time until the next disposable assembly replacement, etc. The indicator may be audible, visible, palpable or combinations thereof. A time remaining indicator may be useful for a variety of reasons. For example, knowledge of the time remaining before the next disposable assembly replacement allows the user to determine, based at least in part on the current time of day and upcoming events (e.g., travel or sleep), whether or not it would be more convenient to replace the disposable assembly300at a time before the end of the dispensing program. Additionally or alternatively, the remote controller can also be configured to generate an indicator for the amount of insulin remaining and/or an indicator for the battery power.

With respect to dimensions, the device100can have a length of about 35-60 mm; a width of about 30-45 mm; and an overall thickness or height of about 8-18 mm. Suitable housing materials include, but are not limited to, plastic or other materials having a modulus of elasticity of 0.2-1.0 million psi.

To use the infusion device100, the user (e.g., the patient) connects the disposable assembly300to the durable assembly200. Unless the reservoir of the disposable assembly300has been sufficiently pre-loaded, the user injects a desired amount of medicament into the reservoir via the fill port106. A plunger seek procedure (detailed below) may be initiated, either by the user or automatically. To adhere the device100to the user, the adhesive backing104may be peeled off to expose the adhesive pad102; the PBUP108may be removed; and/or the device100may be positioned over the chosen body location and pressed gently to adhere the adhesive pad102to the skin surface. In some embodiments, the user triggers the automatic cannula insertion via the remote controller (e.g., after the plunger seek operation is complete). In some embodiments, plunger seek is not required.

The durable assembly200, shown in more detail inFIGS.2A-2C, may include a housing202, a buzzer or other alarm device204, one or more batteries or other energy supply206, a microprocessor (not shown), and a coil assembly208(which functions as a motor stator) including one or more Hall-effect sensors210. In some embodiments, the energy supply206is a rechargeable battery, such as a rechargeable lithium battery, with enough power to drive the motor continuously without needing a capacitor or other additional energy storage device.

Referring specifically toFIG.2C, the coil assembly208can be positioned around a recessed portion212of the durable assembly housing202that is configured to fit over a protruding portion303of the disposable housing302(FIG.3A), which in turn fits over a magnetic motor rotor331of the disposable assembly300(FIG.3B). In this two-piece motor, the motor's coil assembly208is in the durable assembly200and is positioned around the motor rotor331that is part of the disposable assembly300. The Hall-effect sensors210are positioned above the coil assembly208in the durable assembly200. In this configuration, there is a gap between the motor coil assembly208and the motor rotor331. Some or all of the gap may be defined by (and occupied by) housing portions, e.g., durable housing portion212and disposable housing portion303in the illustrated implementation. In other implementations, the gap between the motor coil assembly208and the motor rotor331may be occupied by only a portion of the durable assembly housing202, or only a portion of the disposably assembly housing302, or no structure at all and may simply be an air gap. The size of the gap, which is defined by the distance between the motor coil assembly208and the motor rotor331, is typically about 0.5 mm to 2.0 mm. As such, there is no gear engagement or other mechanical connection between the durable assembly200and the disposable assembly300. All electronics may be positioned within the durable assembly200, with the energy needed by the disposable assembly300transferred by electromagnetic torque coupling, which is a coupling without direct mechanical coupling or electrical contact from the durable assembly200. These designs afford the additional advantage of being relatively simple to make waterproof, or at least water resistant.

An exemplary motor rotor331may be a 2-pole, cylinder-shaped, rare earth (such as neodymium) rotor, magnetized across the diameter, with a 5 mm diameter and 5 mm height. Other suitable motor rotors may be larger or smaller, or be multi-pole. Motor rotors of this type typically cost about 5 cents per piece, helping control the total cost of disposable assembly300. The microprocessor (not shown) directs rotation of motor rotor331by sequentially energizing the coils of motor coil assembly208to create an electromagnetic torque coupling between the motor coil assembly208and the motor rotor331. The position/orientation of the rotor's poles relative to the rotating magnetic field generator (coil assembly208) is measured by back EMF, a rotary encoder(s), one or more Hall-effect sensors210, or the like. For instance, the Hall-effect sensors210mounted above the coil windings208may be used to supply the microprocessor a count, a tachometer signal, or rotor position, allowing low-cost, closed-loop control of the rotor speed. Brushless motors of this type are efficient and run very cool.

The disposable assembly300, shown in more detail inFIGS.3A and3B, may include a reservoir assembly, a trigger assembly304(shown schematically), and an insertion assembly400, all mounted on a baseplate350. The reservoir assembly can comprise a drive assembly329, a reservoir336, a plunger pusher335a, and a plunger335b. The plunger pusher335ais coupled to the drive assembly329, and both the plunger pusher335aand the plunger335bare contained within the reservoir336. The insertion assembly400includes a cannula441(seeFIG.4A) and several components for driving the cannula441into the user's skin. The trigger assembly304can operatively couple one or more components of the reservoir assembly to the insertion assembly400to control the timing of insertion of the cannula441. In some embodiments, for example, one or more components of the trigger assembly304are operatively coupled to the gear train332such that remote activation of the motor moves the trigger assembly304into or out of engagement with the insertion assembly400, thereby actuating the insertion assembly400and releasing the cannula. Additional details regarding remotely-actuatable trigger assemblies are discussed below with reference toFIGS.8-12B.

Referring still toFIGS.3A and3B, the drive assembly can comprise the magnetic motor rotor331and a gear train332. The gear train332is attached to the pusher335awhich is positioned in the reservoir336. The magnetic motor rotor331may be mechanically attached through the gear train332to affect translation of the plunger pusher335a(and the plunger335b, when attached to the plunger pusher335a) within the reservoir336.

As best seen inFIG.3B, the gear train332includes a worm drive comprised of a worm screw333aand a worm gear333b, and also a lead screw nut334aand a fine-pitch lead screw351(enclosed by the lead screw nut334a). The worm gear333bis coupled to the lead screw351via the lead screw nut334a. Protrusions334bon the lead screw nut334acorrespond with recesses (not shown) inside the worm gear333b, and a threaded portion (not shown) inside the lead screw nut334apairs with the thread on the lead screw351enclosed by the lead screw nut334a. The configuration of the gear train332prevents back-driving due to reservoir pressure, eliminating the need for a clutch or other locking mechanism. Suitable materials for the components of the gear train332include, but are not limited to, stainless steel or high strength plastic, such as nylon, acetal (Delrin.RTM.) or polycarbonate.

The reservoir336may be prefilled with a medicament. The medicament, for example, can be U-100 insulin or U-500 insulin or other concentrations of insulin to suit different user use profiles, or may be user-fillable by way of the fill port106(FIG.1B). In some embodiments, the reservoir336can be mounted on a reservoir support block (not shown inFIG.3B). A reservoir outlet fitting348is in fluid communication with the reservoir336. The reservoir outlet fitting348can be made from a drug-compatible material, such as, but not limited to, polypropylene, cyclic olefin polymer (COP) or polyethylene.

In those cases where the reservoir336is filled by the user, the user may completely fill the reservoir to capacity with medicament, or the user may choose to introduce less medicament and not completely fill the reservoir. Since an unknown amount of medicament may be injected into a user-filled reservoir, a plunger-pusher zeroing procedure (or “plunger seek”) may be user-initiated or may be an automatic aspect of pump operation. A plunger seek procedure precisely determines and/or sets, before any medicament dispensing, exactly how far the plunger pusher335atravels before it engages the plunger335b, allowing a calculation to determine the amount of medicament in the reservoir and, therefore, an estimate of time-to-empty and time for disposable assembly replacement.

FIG.3Bshows the reservoir336before any medicament is introduced into the reservoir336. The plunger335bis disconnected from the plunger pusher335a(and thus free-floating) and the plunger pusher335ais in the fully-retracted position. At this point, and until the plunger seek operation is complete, the PBUP108(FIG.1B) remains in place to prevent premature flow of medicament between the reservoir336and the insertion assembly400(except in the hydraulic trigger embodiments discussed below with reference to11A-12B, in which a PBUP may not be necessary). As medicament is introduced into the reservoir336via the fill port106, the plunger335bis pushed towards the plunger pusher335a. If the reservoir336is filled to capacity, the plunger336bwill be pushed into contact with the plunger pusher335a. In some embodiments, this causes the hooks337(or other suitable method of attachment) on the plunger335bto engage with and permanently lock with the pusher335a. If the reservoir336is not filled to capacity, the plunger335bwill be positioned at some unknown point within the reservoir336until the plunger seek operation is complete. Once the user has introduced medicament into the reservoir336, a plunger seek operation can be initiated by the user or may be an automatic aspect of pump operation. When the plunger seek operation is initiated, the motor advances the plunger pusher335auntil it contacts the plunger335b. In some embodiments, they lock together with plunger hooks337or some other suitable method of attachment. In some embodiments, the plunger pusher335aand the plunger335bare not configured to mechanically lock. The reservoir336and the plunger335bmay be made of cyclic olefin polymer (COP), polypropylene or other drug-compatible polymeric material. Suitable materials for the plunger pusher335ainclude, but are not limited to, stainless steel, COP, nylon, and polycarbon.

As previously mentioned, the plunger seek operation is performed when flow from the reservoir336is blocked by the PBUP108. Given there may be tolerances associated with cartridge manufacture and variation in medicament filling, there may be variations in the distance that the plunger pusher335atravels from its initial home position before it contacts the plunger335b. Under microprocessor control, the motor advances the plunger pusher335ainto contact with the plunger335b, causing increased fluid path pressure. The Hall-effect sensors210, an encoder, or other monitoring/sensing device is sampled to determine when a motor stall occurs as the plunger pusher335ais advanced. Lack of signals from the Hall-effect sensors210indicates that the motor is not turning. The motor stall is presumed to be due to hydraulic lock and, therefore, indicative of the plunger pusher335acontacting the plunger335bof a plugged device. In some embodiments, the procedure may employ two or more speeds for advancing the plunger pusher335a. Also, the plunger pusher335amay be advanced at a controlled torque, or limited force, so that the motor will stall with the least amount of force possible for reliable results, in order to reduce the load on the system (e.g., the bearings and the battery). As stated above, knowing the distance the plunger pusher335atraveled before contacting the plunger335ballows calculations of medicament volume and estimated time until replacement of the disposable assembly300.

In some embodiments, instead of or in addition to sensing motor stall (as described above), the device100can be configured to sense an increased load on the motor. For instance, the device100can be configured to sense a motor speed reduction that is less than 100% (which would be equivalent to a motor stall), which could be sensed sooner than a motor stall. The device100can be configured to sense, for example, a 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80% or 90% in speed reduction. Suppose, for example, the device100is running the motor in a speed-controlled manner by varying the motor current to control the speed. When the reservoir pressure increases, the motor current is increased to maintain a desired speed. Accordingly, the device100is configured to sense occlusion and plunger seek by sensing increases in motor load. This increased load can be sensed by a number of ways such as power increase, speed decrease, etc.

The insertion assembly400is shown in greater detail inFIGS.4A and4B.FIGS.4A and4Bshow the insertion assembly400in a cocked and locked position (e.g., before the user removes the PBUP108and remotely activates the trigger assembly304). The insertion assembly400can comprise a cylindrical guide housing420, a main insertion spring410, a cannula carrier412, and a cannula441fixed to the cannula carrier412. The cannula carrier412further includes a trigger boss411that is configured to engage with the trigger assembly304to move (or allow movement of) the cannula carrier412. The main insertion spring410extends between a top ledge of the guide housing420and a portion of the cannula carrier412. When the insertion assembly400is in a pre-insertion position (shown inFIG.4A), the main insertion spring410is in a compressed state and exerts a downward force on the cannula carrier412. Engagement between the cannula carrier412and a support ledge422(FIG.4B) of the guide housing420holds the main insertion spring410in a compressed state and prevents downward motion of the cannula carrier412.

The insertion assembly400also includes a trocar447, a trocar carrier474, a trocar seal480, a trocar retraction spring482, a cannula seal430, seal rings431, and a cannula seal retainer434. The trocar447, which comprises an elongate rod with a sharp distal tip, may be made of metal, such as stainless steel, or other relatively rigid biocompatible material, such as rigid plastic, ceramic, or other rigid biocompatible material, and is used to penetrate the skin and a short distance into the flesh, to make a channel for cannula441. The cannula441may be made of polytetrafluoroethylene (PTFE), such as TEFLON.RTM. PTFE, or other biocompatible polymeric material. As described further below, these components provide a highly efficient cannula seal with low cannula insertion forces and a highly reliable medicament seal. The components involved and details of how the insertion assembly400performs these actions are described in more detail below.

The insertion assembly400may be a4-state system.FIGS.4A-4Bshow the insertion assembly400in its first state: the cocked position (e.g., before the user removes the PBUP108and remotely activates the trigger assembly304to insert the cannula441). In this state, the PBUP108is positioned to occlude the fluid path from the reservoir336and the cannula carrier412is held up above and spaced apart from the cannula seal430, as described further below. In this state, and as best seen inFIG.3B, the plunger seek procedure described above can advance the plunger pusher335ainto contact with the plunger335b, slightly pressurizing the reservoir336, without injecting medicament into the user. As best seen inFIG.4A, a seal is formed between the seal rings431and the outer surface of PBUP108, allowing the pressures for plunger seek.

FIGS.5A-5Dshow the insertion assembly400in its second state. In this state, the PBUP108has been removed and the insertion assembly400is ready to fire. The fluid path from the reservoir336(FIG.3A) is open to the atmosphere, and any residual pressure is vented before cannula insertion.

As will be described in greater detail below, removal of the PBUP108allows cannula insertion, which may be triggered based on activating the trigger assembly304via the remote controller. Triggering cannula insertion may cause the trocar447and the cannula441(best seen inFIG.5D) to project out of the disposable assembly300(that is state three, shown inFIGS.6A and6B), and then cause the trocar447to retract back into the insertion assembly400, leaving the cannula441in place (which is state four, shown inFIGS.7A-7D).

FIG.5Bshows the insertion assembly400with the main insertion spring410and the guide housing420removed. InFIG.5C, the main insertion spring410is removed and guide housing420is semi-transparent.FIG.5Dis a section view of the components ofFIG.5C. The main insertion spring410may provide travel of about 7 mm with a starting force of about 15 newtons (N) and an ending force of about 7 N, and may be made of, for instance, 0.75 mm diameter music wire, with 6 turns and an outside dimension of 13.25 mm. The trocar retraction spring482may provide travel of about 7 mm with a starting force of about 4 N and an ending force of about 1 N, and may be made of, for instance, 0.5 mm diameter music wire, with 6 turns and an outside dimension of 3 mm. The guide housing420and the cannula seal retainer434may be made of high strength plastic, such as nylon, acetal (Delrin.RTM.) or polycarbonate. The cannula carrier412and the trocar carrier474may be made of COP, polypropylene or other similar drug-compatible material. The trocar seal480and the cannula seal430may be made of elastomer, rubber, such as silicone rubber or bromobutyl rubber, or other relatively conformable sealing material that is also drug-compatible.

As mentioned above,FIGS.5A-5Dshow the insertion assembly400in state two, the cocked position (e.g., before the user remotely activates the trigger assembly304to cause the cannula carrier412to drive the cannula441into an inserted position). Before insertion, the cannula carrier412is supported on the support ledge422of the guide housing420(best seen inFIG.5D), which in turn holds the main insertion spring410in a compressed state. Note that the guide housing420does not move during cannula insertion.

Activation of the trigger assembly304causes the cannula carrier412to rotate such that the carrier tabs413move away from the support ledge422and align with slots424in the guide housing420(shown inFIGS.4B,5A, and5C). While the cannula carrier412is shown rotating counterclockwise to release, in other embodiments the cannula carrier may rotate clockwise to release (in such embodiments, the slots424may be disposed immediately to the left of the tabs413). Once the cannula carrier412is no longer supported by the guide housing ledge422, the cannula carrier412can no longer resist the force of the main insertion spring410, and the elastic energy contained in the main insertion spring410is converted to motion. The main insertion spring410drives the cannula carrier412with the attached cannula441, the trocar carrier474with the attached trocar447, the trocar seal480, and the trocar retraction spring482downward. As these components move downward, the sharp distal tip of trocar447, which extends slightly beyond the distal end of the cannula441, penetrates the user's skin, and the cannula441, which surrounds trocar447, is inserted so the end of the cannula441is about 6 mm below the surface of the user's skin. At this point, the insertion assembly400is in state three, as seen inFIGS.6A and6B.

As best seen inFIGS.5B,6B, and7B, the cannula carrier412and the trocar carrier474include features to lock them together before and during cannula insertion. The trocar carrier474includes locking ledges475(labeled inFIG.7Bonly) that fit beneath locking bosses415(FIGS.6B and7Bonly) on the cannula carrier412. When the cannula carrier412and the trocar carrier474are locked together, the trocar retraction spring482is held in a compressed state. In addition, the trocar carrier474includes locking ledge walls477that contact locking boss walls417on the cannula carrier412. These walls ensure that the trocar carrier474moves together with the cannula carrier412(e.g., only counter-clockwise, or whatever rotational direction the cannula carrier412is moving), so trocar carrier's locking ledges475cannot accidently slide out from under the cannula carrier's locking bosses415and unintentionally trigger penetration of the trocar447.

Once the cannula carrier412and trocar carrier474are rotated to begin cannula insertion and move downward toward the user, angled edges479of tabs478on the trocar carrier474contact corners435on the seal retainer434. As the trocar carrier474moves downward, the contact between the corners435and the angled edges479causes the trocar carrier474to rotate further and further (e.g., counter-clockwise) during cannula insertion. As the cannula carrier412moves downward, the carrier tabs413become aligned with slots424in the guide housing420(shown inFIGS.4B,5A, and5C), thereby allowing the cannula carrier412to slide downward while preventing additional rotation of the cannula carrier412. As the trocar carrier474rotates further counter-clockwise, the trocar carrier's locking ledges475slide out from under the cannula carrier's locking bosses415.

FIGS.6A and6Bshow the insertion assembly400in state three:FIG.6Ashows the main insertion spring410fully fired, the cannula carrier412fully down, and the cannula441fully inserted, at the instant the trocar carrier474is released and before the trocar retraction spring482drives the trocar carrier474and the trocar447upward. (As shown, the skin is pierced at about 90 degrees and the end of the cannula is positioned about 6 mm below the surface of the skin.)FIG.6Bshows the same instant, with the main insertion spring410and the guide housing420removed. This view shows the moment the trocar carrier's locking ledges475are released from under the cannula carrier's locking bosses415.

Once the trocar carrier's locking ledges475are released from under the cannula carrier's locking bosses415(this is also the moment that the cannula441is fully inserted, and the insertion assembly400is in state three, as seen inFIGS.6A and6B), the trocar carrier474can no longer resist the force of the trocar retraction spring482. The elastic energy contained in the trocar retraction spring482is converted to motion, and the trocar retraction spring482drives the trocar carrier474with the attached trocar447upward. As the trocar carrier474moves upward, the trocar447is removed from the user and retracted back into the insertion assembly400, leaving the cannula441inserted. This is state four, as seen inFIGS.7A-7D.

FIG.7Ais a section view showing the insertion assembly400fully fired and the trocar447fully retracted.FIG.7Bshows more details of the fully fired insertion assembly400, with the main insertion spring410and the guide housing420removed. This is the position of the components of insertion assembly400while the device100is in use (e.g., during fluid delivery) by the user. The medicament path is best seen inFIGS.7A and7C. Broadly stated, medicament flows from the reservoir (not shown), to the outlet fitting348, into a channel in the cannula seal430, through a channel414in cannula carrier412, through the trocar seal480, and into the cannula441for delivery to the user.

Best seen inFIGS.7C and7Dis the highly efficient radial compression hydraulic seal formed between the cannula carrier412and the upper and lower seal rings431of the cannula seal430. The upper and lower seal rings431can be separated by about 2.5 mm. Tapering of the cannula seal430to the small contact areas of the seal rings431concentrates surface stresses where the seal rings431contact the cannula carrier412, to provide a good seal. Additional upper and lower seal rings are possible, but could increase space requirements. To enhance the seal at the seal rings431, the main insertion spring410exerts force on the cannula carrier412, holding it down against the baseplate350and causing an internal surface416of the cannular carrier412to push on the top surface of the cannula seal430, as described in more detail below.

During the transition from state two to state three of insertion, the internal surface416of the cannula carrier412begins contacting the top of the cannula seal430before the bottom surface of the cannula carrier412contacts the baseplate350. When state three is reached, the bottom surface of the cannula carrier412is held against the baseplate350and the cannula seal430is compressed from above. The high-energy main insertion spring410improves sealing reliability, and the cannula seal430acts as a bumper as it is compressed, helping dissipate the energy of insertion. Rather than being wasted, or converted to user-perceptible noise and feeling, residual energy from firing of the main insertion spring410is converted from kinetic energy to enhanced radial compression of the cannula seal430.

In addition, the contact between the internal surface416of the cannula carrier412and the top surface of the cannula seal430forms a secondary face seal. In state three, the main insertion spring410continues pushing down on the cannula carrier412, with approximately 7-10 N of force. This force, spread over the top surface of the cannula seal430, results in a fluid seal capable of sealing approximately 3 bar, in addition to the seal maintained at the upper seal ring431.

To further enhance this seal, the seal retainer434provides radial support, acting as a fixed backing ring/clamp, increasing the radial compression around the cannula seal430. Even further enhancing the seal, the cannula carrier412provides additional radial compression with clamping force on the cannula seal430, acting as an additional backing ring/clamp. The 7-10 N residual force derived from the main insertion spring410results in downward (axial) compression on the cannula seal430, causing radial deformation of the cannula seal430, further improving the seal formed between the cannula carrier412and the seal rings431. In state three, since the cannula seal430is radially constrained by the seal retainer434and the cannula carrier412, axial compression of the cannula seal430causes radial deformation of the seal430, increasing the sealing force on the sealing rings431. All of this results in a highly efficient and reliable hydraulic cannula seal.

Turning now toFIG.7C, the medicament path also includes a compression-type fitting490formed from a clamp-portion436of the seal retainer434clamping ferrule432of the cannula seal430down onto barb349of outlet fitting348. As an alternative, a separate component can be utilized to deliver the clamping forces provided by the clamp-portion436of the seal retainer434. In addition, the ferrule432of the cannula seal430and the barb349of the outlet fitting348can be separate ferrule and barb components, but would introduce additional component interfaces along the medicament path, each requiring additional sealing features. In the configuration shown, the cannula seal430seals the cannula441, absorbs energy during firing by compressing when struck by the cannula carrier412, and helps seal the reservoir336with the ferrule432.

As best seen inFIG.7D, the medicament next flows through the ferrule432, through the cannula seal430, through the channel414in the cannula carrier412, through the trocar seal inlet481, through the trocar seal channel483, and through the cannula441for delivery to the user. As can be seen from comparingFIGS.5D,6A, and7A, the trocar seal480remains in one position within the cannula carrier412before, during, and after the insertion process, and remains in that position during user use of the device100. The trocar seal480includes sidewall seal rings484and base seal rings486. The sidewall seal rings484prevent medicament leakage into the cannula carrier412and, ultimately, into the device100. The base seal rings486prevent leakage from around the cannula441, and ensure that medicament flowing from the trocar seal inlet481and through the trocar seal channel483is directed into the cannula441.FIG.7Dshows a pair of the sidewall seal rings484and a pair of the base seal rings486, but additional seals may be used for additional leak protection.

The insertion assembly400provides a highly efficient, highly reliable medicament seal with low insertion forces, all in a compact space. The energy supplied to insert the cannula441is provided by the main insertion spring410, and sufficient to:allow the trocar447to quickly and cleanly pierce the user's skin for cannula insertion;overcome friction forces during movement of the cannula carrier412surfaces against the cannula seal430surfaces and the seal retainer434surfaces; andresult in compression and radial forces making a reliable medicament seal.

Excess energy is absorbed by compression of the cannula seal430, which radially expands the cannula seal430, increasing the radial forces exerted by the seal rings431against the surface of the cannula carrier412and exerted by the cannula seal430against the seal retainer434, as explained in more detail below. Energy requirements and expenditures are also described in more detail presently.

During operation, as the insertion assembly400transitions from state two to state three, the radial compression forces exerted on the cannula seal430increase. As the cannula carrier412moves downward, it contacts the upper cannula seal ring431, and, generally, causes the cannula seal430to be captured and surrounded between the surfaces of the cannula carrier412and the seal retainer434. The seal retainer434acts as a fixed backing ring, providing radial support for the cannula seal430, contributing to the radial clamping forces applied to the cannula seal430. However, in some alternatives, there may be a small gap between the seal retainer434and the cannula seal430until the cannula seal430is compressed downward and expanded radially, as explained momentarily. The radial forces applied to the cannula seal430increase as the cannula carrier412continues moving downward, since the amount of contact, and therefore radial force, continues increasing between (i) the surfaces of the cannula carrier412and the cannula seal rings431, (ii) the seal retainer434and the cannula seal430, and (iii) in some alternatives, the surfaces of the cannula carrier412and the seal retainer434. Contact between the cannula carrier412and the seal rings431during transition from state two to state three is also described in more detail below, in relation to the next embodiment.

As the cannula carrier412continues moving downward, contact is made between the top surface of the cannula seal430and the carrier internal surface416(seeFIGS.5D and7D). As explained above, this contact occurs while the cannula carrier412is still moving downward. Therefore, as the cannula carrier412continues moving downward, the internal surface416of the cannula carrier412exerts increasing downward force on the cannula seal430, and as it does, the cannula seal430is increasingly compressed as the cannula carrier412continues moving. As the carrier internal surface416pushes more and more on the cannula seal430from above, the cannula seal430expands more and more radially, resulting in additional radial compression forces between (i) the seal rings431and the cannula carrier412and (ii) the cannula seal430and the seal retainer434. The cannula seal430may ultimately radially expand by, for instance, 0.5 mm. (In some alternatives, a small gap between the seal retainer434and the cannula seal430may decrease until it is eliminated as the cannula seal430expands radially due to downward compression of the cannula seal430by the internal surface416of the cannula carrier412.) In addition, as described above, contact between the internal surface416of the carrier412and the top surface of the cannula seal430forms a secondary face seal. As such, a highly efficient and highly reliable cannula seal is achieved by (1) this face seal formed at the internal surface416of the cannula carrier412and the top surface of the cannula seal430, (2) contact between the seal rings431and the cannula carrier412, (3) radial clamping forces exerted on the cannula seal430by the seal retainer434, (4) increased radial clamping forces exerted by the cannula carrier412, acting as an additional backing ring (in addition to seal retainer434) and providing increased radial compression of the cannula seal430, and (5) downward force exerted on the top of the cannula seal430by the cannula carrier412at the internal surface416of the cannula carrier412, which expands the cannula seal430radially and increases the radial forces exerted (a) by the seal rings431against the surface of the cannula carrier412and (b) by the cannula seal430against the seal retainer434.

I. Selected Embodiments of Trigger Assemblies

FIGS.8-12Billustrate representative examples of disposable assemblies800,900,1000, and1100with remotely actuatable trigger assemblies of various configurations in accordance with embodiments of the present technology. The features of the disposable assemblies800,900,1000, and1100can be generally similar to the features of the disposable assembly300ofFIGS.1A-7D. Accordingly, like numbers are used to identify similar or identical components inFIGS.1A-7D, and the discussion of the disposable assemblies800,900,1000, and1100ofFIGS.8-12Bwill be limited to those features that differ from the disposable assembly300ofFIGS.1A-7D. Additionally, any of the features of the disposable assemblies800,900,1000, and1100ofFIGS.8-12Bcan be combined with each other and/or with the features of the disposable assembly300ofFIGS.1A-7D.

In any of the infusion device embodiments disclosed herein, the trigger assembly304can be configured to push or pull a portion of the cannula carrier412to cause the tabs413of the cannula carrier412to rotate into alignment with the slots424(FIG.4B) in the guide housing420. For example,FIG.8shows a disposable assembly800having a trigger assembly coupled to the drive assembly329of the reservoir assembly. The trigger assembly can comprise a shaft802, a rod804, a clutch disc806, and a lever808. The rod804has a first end portion804aadjacent the trigger boss411of the cannula carrier412and a second end portion804badjacent the lever808. The lever808can be coupled to a stationary portion of the reservoir assembly via a pin807, and has first and second lever arms808a,808bthat are configured to rotate about the pin807. The lever808does not translate forward when the plunger pusher335atranslates forward. The first lever arm808ais positioned adjacent an end of the rod804and, when the trigger assembly is activated, the first lever arm808arotates in a counterclockwise direction, thereby pushing the rod804forward, towards the trigger boss411of the cannula carrier412(as indicated by arrow B). The clutch disc806is disposed at the second lever arm808b. The shaft802has a first end (not visible) fixed to the plunger pusher335a(or another component that moves with the plunger plusher335a) and a second, free end. As the shaft802extends rearwardly from the plunger pusher335a, it passes through an opening in the clutch disc806disposed at the second lever arm808b.

When the drive assembly329of the reservoir assembly operates in a forward direction (for example, during a plunger seek operation), the shaft802translates forward with the plunger pusher335a. The clutch disc806allows the shaft802to pass therethrough in this forward direction. However, when the motor is reversed (for example, after a plunger seek operation is complete) and the plunger pusher335amoves in a rearward direction, the clutch disc806clamps down on the shaft802and prevents rearward translation of the shaft802through the clutch disc806. As a result, the shaft802becomes a substantially rigid body with the second lever arm808bsuch that the shaft802pulls the second lever arm808bcounterclockwise about the pin807. This rotation of the second lever arm808bcauses rotation of the first lever arm808a, which engages the second end portion804bof the rod804to push the rod804forward (as indicated by arrow B). Forward translation of the rod804forces the first end portion804aof the rod804into contact with the trigger boss411of the cannula carrier412and pushes the cannular carrier412clockwise (as indicated by arrow C) to trigger cannula insertion.

In use, the user positions the device (including the disposable assembly800) on the skin with the trigger assembly in a locked state. Once the device is adhered to the user's skin (e.g., after the plunger seek operation is complete and the PBUP108is removed), the user can trigger cannula insertion by interfacing with a remote controller to indicate a desire to trigger cannula insertion. The user may, for example, press a button on the touchscreen of the user's mobile device. In response to the user's indication, the remote controller may communicate a command to the device (for example, via the microprocessor of the durable assembly200) that causes the motor to run in reverse. In response to the reversed motor, the plunger pusher335amoves rearwardly, thus rotating the lever808and, via translation of the rod804, forcing the tabs413of the cannula carrier412to rotate into alignment with the slots424of the guide housing420for cannula insertion. After triggering, the plunger pusher335ais advanced back into contact with the plunger335bto begin delivery of the medicament.

In some embodiments of the disposable assembly800, the rod804is configured to pull on the trigger boss411rather than push as detailed above. For example, the first end portion804aof the rod804may be positioned to the right of the trigger boss411and connected thereto via one or more linkages.

According to several embodiments, the cannula carrier412of the insertion assembly400is biased towards rotating in a direction that would release the cannula carrier412from the guide housing420. In such embodiments, the trigger assembly may comprise a blocking member that prevents such rotational motion until the user remotely activates the trigger assembly to remove the blocking member and release the cannula carrier412. For example, the blocking member can engage a portion of the cannular carrier412(such as the trigger boss411) to prevent rotation of the cannula carrier412in the direction of release. Remote activation of the trigger assembly causes the blocking member to disengage from the trigger boss411, thereby allowing the cannula carrier412to rotate such that the tabs413on the carrier412align with the slots424in the guide housing420. Alignment of the tabs413with the slots424enables the downward motion of the cannula carrier412and insertion of the cannula441.

To rotationally bias the cannula carrier412, the insertion assembly400may include a torsion spring. In some embodiments, the ledges422(seeFIG.4B) of the guide housing420can slant downwardly towards the slots424such that, when the blocking member is removed, the cannula carrier412can no longer resist the force of the main insertion spring410, and the elastic energy contained in the main insertion spring410is converted to motion. Because of the slanted ledges422, the cannula carrier412rotates as it moves downwardly until the tabs413sitting on the ledges422align with the slots424on the guide housing420.

FIGS.9A-9Care different views of a disposable assembly900having a rotationally-biased cannula carrier412and a trigger assembly operatively coupled to the drive assembly329. The trigger assembly can comprise a rod902, a latch904, and a ratchet wheel910coupled to the worm gear333bof the reservoir assembly such that rotation of the worm gear333bcauses rotation of the ratchet wheel910. The rod902has a first end902aabutting the trigger boss411on the cannula carrier412, and a second end902breceived within an opening920(FIG.9B) in the reservoir support block338. In some embodiments, for example as shown inFIGS.9A-9C, the rod902is oriented parallel to a longitudinal axis of the reservoir336. The reservoir336, the reservoir support block338, and/or another component of the disposable assembly900can include a groove906(FIG.9B) configured to receive at least a portion of the rod902to guide translation of the rod902and prevent lateral movement (e.g., any movement that is not parallel to the longitudinal axis of the reservoir336).

When the trigger assembly is in a locked state (pre-insertion, as shown inFIGS.9A-9C), translation of the rod902beyond the opening920(in a direction away from the insertion assembly400) is prevented by a first end904aof the latch904. For example, the latch904can sit in a channel914in the support block338that positions the first end904aof the latch904between the second end902b(FIG.9C) of the rod902and a backstop908on the support block338. As previously described, the cannula carrier412can be biased towards rotating in a particular direction (here shown as counterclockwise, as indicated by arrow D), but is prevented from doing so by the rod902which is trapped between the trigger boss411on the cannula carrier412and the first end904aof the latch904. Because of the continuous force exerted on the rod902by the cannula carrier412, the rod902is biased towards translating rearwardly (towards the support block338, as indicated by arrow C), but is prevented from doing so by the presence of the first end904aof the latch904across the opening920.

A second end904bof the latch904can be engaged with a tooth912(FIG.9B) on the ratchet wheel910. When the worm gear333brotates counterclockwise (for example, to advance the plunger pusher335aforward during a plunger seek operation), the ratchet wheel910also rotates counterclockwise. During such rotation the teeth912of the ratchet wheel910do not engage the latch904so as to move the first end904aof the latch904away from the opening920. When the motor is reversed and the worm gear333bruns clockwise (arrow A inFIG.9B), the ratchet wheel910also rotates clockwise. During such rotation, one of the teeth912of the ratchet wheel910can engage the second end904bof the latch904and pull the latch904in a direction away from the second end902bof the rod902and the opening920(indicated by arrow B). Once the latch904has cleared the opening920, the rod902is free to slide through the opening920, which allows the cannula carrier412to rotate (indicated by arrow D). Rotation of the cannula carrier412aligns the tabs413on the carrier412with the slots424in the guide housing420(seeFIG.4B), thereby allowing the main spring410to push the cannula carrier412downwardly and insert the cannula441.

In use, the user positions the device (including the disposable assembly900) on the skin with the trigger assembly in a locked state. Once the device is adhered to the user's skin (e.g., after a plunger seek operation is completed, if needed, and the PBUP108is removed), the user can trigger cannula insertion by interfacing with a remote controller to indicate a desire to trigger cannula insertion. The user may, for example, press a button on the touchscreen of the user's mobile device. In response to the user's indication, the remote controller may communicate a command to the device (for example, via the microprocessor of the durable assembly200) that causes the motor to run in reverse. In response to the reversed motor, the worm gear333band ratchet wheel910rotate clockwise, thus moving the latch904and allowing the cannula carrier412to drop for insertion. After triggering, the plunger pusher335ais advanced back into contact with the plunger335bto begin delivery of the medicament.

FIGS.10A-10Care different views of a disposable assembly1000having a trigger assembly operatively coupled to the drive assembly329. In contrast to the disposable assembly900shown and described with respect toFIGS.9A-9C, the cannula carrier412of the disposable assembly1000is not rotationally biased and requires forced rotation to trigger cannula insertion. The trigger assembly can comprise a rod1002, a latch1004, and a ratchet wheel1010coupled to the worm gear333bsuch that rotation of the worm gear333bcauses rotation of the ratchet wheel1010. The rod1002has a first end portion1002aabutting the trigger boss411on the cannula carrier412, and a second end portion1002breceived within an opening in the reservoir support block338. In some embodiments, for example as shown inFIGS.10A-10C, the rod1002is oriented parallel to a longitudinal axis of the reservoir336. The reservoir336, the reservoir support block338, and/or another component of the disposable assembly1000can include a groove1006(FIG.10C) configured to receive at least a portion of the rod1002to guide translation of the rod1002and prevent lateral movement (e.g., any movement that is not parallel to the longitudinal axis of the reservoir336).

When the trigger assembly is in a locked state (pre-insertion, as shown inFIGS.10A-10C), the second end portion1002bextends beyond the opening920in the reservoir support block338(in a direction away from the insertion assembly400) and is adjacent a first end portion1004aof the latch1004. For example, the latch1004can sit in a channel1014in the support block338. A second end1004bof the latch1004can be engaged with a tooth1012(FIG.10B) on the ratchet wheel1010such that when the ratchet wheel1010rotates in a counterclockwise direction (arrow A inFIG.10B), the tooth1012pushes the latch1004towards the second end1002bof the rod1002(indicated by arrow B). The counterclockwise direction can be the reverse of the normal direction of rotation of the motor, which in this case is in the clockwise direction. The latch1004can have a beveled end surface1005such that, as the latch1004engages the second end portion1002bof the rod1002, the beveled end surface1005pushes the rod1002forwardly (indicated by arrow C). Forward motion of the rod1002causes the first end portion1002ato engage the trigger boss411and force rotation of the cannula carrier412(indicated by arrow D). Rotation of the cannula carrier412aligns the tabs413on the carrier412with the slots424in the guide housing420(seeFIG.4B), thereby allowing the main spring410to push the cannula carrier412downwardly and insert the cannula441.

In use, the user positions the device (including the disposable assembly1000) on the skin with the trigger assembly in a locked state. Once the device is adhered to the user's skin (e.g., after a plunger seek operation is completed, if needed, and the PBUP108is removed), the user can trigger cannula insertion by interfacing with a remote controller to indicate a desire to trigger cannula insertion. The user may, for example, press a button on the touchscreen of the user's mobile device. In response to the user's indication, the remote controller may communicate a command to the device (for example, via the microprocessor of the durable assembly200) that causes the motor to run in reverse. In response to the reversed motor, the worm gear333band ratchet wheel910rotate counterclockwise, thus pushing the latch1004into engagement with the rod1002. Thus, the rod1002moves in a forward direction and causes the tabs413of the cannula carrier412to rotate into alignment with the slots424in the guide housing420, thereby triggering cannula insertion. After triggering, the plunger pusher335ais advanced back into contact with the plunger335bto begin delivery of the medicament.

As previously mentioned, in some embodiments the cannula carrier412of the insertion assembly400is biased towards rotating in a direction that would cause cannula insertion. For example, a trigger assembly of the present technology can comprise a hydraulic trigger configured to permit movement of the cannula carrier412.FIG.11Ashows a top view of a disposable assembly1100having a trigger assembly that includes a hydraulic slave cylinder1101configured to share a fluid connection with the reservoir336. The slave cylinder1101can include a housing1104, a piston1108at least partially positioned within the housing1104, a seal1112(seeFIG.11B) between the piston1108and the housing1104, and a spring-loaded pin1106positioned between an end portion of the piston1108and a portion of the cannula carrier412. The piston1108can include a channel1110(seeFIG.11B) extending through its thickness and configured to receive at least a portion of the pin1106.

Referring toFIG.11B, the housing1104can have a first opening through which the piston1108extends, a second opening1114through which the housing1104is configured to share a fluid connection with the reservoir336, and a third opening1119across which a valve1118is positioned. Medicament from the reservoir can flow into the housing1104through the second opening1114and into a space defined by the sidewalls of the housing1104, the piston1108, and the valve1118.

In use, the user positions the device (including the disposable assembly1100) on the skin with the trigger assembly in a locked state. Once the device is adhered to the user's skin (e.g., after a plunger seek operation is complete, if needed), the user can trigger cannula insertion by interfacing with a remote controller to indicate a desire to trigger cannula insertion. The user may, for example, press a button on the touchscreen of the user's mobile device. In response to the user's indication, the remote controller may communicate a command to the device that causes the motor to push the plunger forward and deliver medicament into the housing1104. This delivery of medicament pushes the piston1108away from the housing1104such that the channel1110aligns with the spring-loaded pin1106. As shown inFIGS.12A and12B, when the channel1110aligns with the spring-loaded pin1106, the pin1106drops into the channel1110, thereby disengaging the cannula carrier412and allowing the tabs413of the carrier412to rotate into alignment with the slots424in the guide housing420. Now positioned in the channel1110, the pin1106advantageously locks the piston1108in place to prevent excessive compliance.

In addition to inserting the cannula441into the patient, the downward motion of the cannula carrier412causes a tubular connector1120to pass through the valve1118and establish a fluid path between the reservoir336and the cannula441. The valve1118can be a check valve and the downward motion of the connector1120can crack the check valve. Other means for establishing a fluid path between the cannula441and the reservoir336are possible. For example, the valve1118can be a septum and the tubular connector1120can be a needle that pierces the septum when the cannula carrier412drops. In some embodiments, the valve1118is a ball valve and establishing the fluid path comprises spinning the ball valve. In any case, use of a hydraulic trigger can advantageously obviate the need for the PBUP108, as the outflow from the reservoir336is already contained by the hydraulic slave cylinder.

To prevent triggering the cannula release prematurely while filling the reservoir336, the device can be configured such that the pressure required to push the piston1108is greater than the pressure to push the plunger335bwithout using the motor. For example, the disposable assembly1100can be configured such that the piston friction is greater than the pressure attributable to filling the reservoir336with a syringe but still less than the pushing force exertable by the motor and less than the leak pressure of a stopper seal.

In some embodiments, the housing1104can include an additional opening in its sidewall (not illustrated) and a gas permeable membrane can extend across the opening. In such embodiments, the slave cylinder can further include a septum between the gas permeable membrane and the flow path to the reservoir (e.g., through second opening1114). The trigger assembly can include a needle extending from the end of the piston1108through the septum. Sterilant (such as ethylene oxide) can enter the housing1104through the membrane and cross the septum through the needle lumen. The needle can have an opening in its sidewall disposed at a location along the needle that remains on the piston side of the septum. As such, sterilant entering through the membrane can pass through the septum, into the housing lumen via the opening in the needle, and into the reservoir336via the second opening1114.

In any of the embodiments disclosed herein, the device can be configured to detect the relative positions of different portions of the trigger assembly and/or cannula carrier to determine an insertion state of the device. For example, for the trigger assembly shown inFIGS.11A-12B, the relative positions of the pin1106and piston1108can be measured. In some embodiments, the pin1106includes a magnet (not shown) and the portion of the piston1108distal of the channel1110also includes a magnet (not shown). The magnet on the pin1106can be oriented such that, in a pre-insertion position, the north pole of the pin magnet is closest to the piston1108, and the north pole of the piston magnet is closest to the pin1106. The durable assembly200(or another portion of the infusion device) can include a magnetoresistive sensor that is configured to detect a change in the proximity of the north poles of the pin and piston magnets. Proximity detection of the pin1106relative to the piston1108(or vice versa) can be beneficial for detecting insertion and for distinguishing cannula insertion from a pre-insertion state. Moreover, because the infusion device can detect insertion, the infusion device can resume basal delivery automatically (if a basal rate was previously set). The relative positions of the pin1106and piston1108can also initiate plunger seek (in addition to or instead of when the force peaks at the motor).

For many of the components described above inFIGS.1A-12B, rotational movement is described in a certain direction (e.g., either clockwise or counterclockwise). It will be appreciated that the component and/or device can also be configured to perform its intended function by moving in the opposite direction. For example, the worm gear is described below as rotating counterclockwise to push the plunger pusher forward and clockwise to reverse the plunger pusher. In some embodiments, the worm gear may be configured to rotate clockwise to push the plunger pusher forward and counterclockwise to reverse the plunger pusher. As another example, the cannula carrier is often described as rotating counterclockwise to release the carrier tabs413. In some embodiments, however, the cannula carrier may be configured to rotate clockwise to release the carrier tabs413. The motor and/or drive assembly, cannula carrier, ratchet wheel, lever, and/or any component that rotates may similarly have embodiments in which a direction of rotation to achieve a desired outcome is opposite of what is described above.

Conclusion

Although the devices and methods are described in the context of automatic cannula insertion and patch pumps, it should be appreciated that the techniques are equally applicable to a variety of medical devices (e.g., infusion ports) and to a variety of at least partially implantable devices (e.g., sensors). It should also be noted here that the specification describes structures and methods that are especially well-suited for the subcutaneous delivery of high concentration insulin (i.e., U-200 insulin and above) such as U-500 insulin as well as lower concentration insulin such as U-100 insulin. Nevertheless, it should be appreciated that the present inventions are applicable to a wide variety of infusion pumps and medicaments. For example, the present inventions are also applicable to medicaments such as, for example, drugs to mask pain, chemotherapy and other cancer related drugs, antibiotics, hormones, GLP-1, glucagon, various other drugs that include large molecules and proteins that may require a high level of delivery accuracy, as well as to relatively high concentration insulin (i.e., U-200 insulin and above) such as U-500 insulin, as well as lower concentration insulin, such as U-100 insulin.

The descriptions of embodiments of the technology are not intended to be exhaustive or to limit the technology to the precise form disclosed above. Where the context permits, singular or plural terms may also include the plural or singular term, respectively. Although specific embodiments of, and examples for, the technology are described above for illustrative purposes, various equivalent modifications are possible within the scope of the technology, as those skilled in the relevant art will recognize. For example, while steps are presented in a given order, alternative embodiments may perform steps in a different order. The various embodiments described herein may also be combined to provide further embodiments.

As used herein, the terms “generally,” “substantially,” “about,” and similar terms are used as terms of approximation and not as terms of degree, and are intended to account for the inherent variations in measured or calculated values that would be recognized by those of ordinary skill in the art.

Moreover, unless the word “or” is expressly limited to mean only a single item exclusive from the other items in reference to a list of two or more items, then the use of “or” in such a list is to be interpreted as including (a) any single item in the list, (b) all of the items in the list, or (c) any combination of the items in the list. Additionally, the term “comprising” is used throughout to mean including at least the recited feature(s) such that any greater number of the same feature and/or additional types of other features are not precluded. It will also be appreciated that specific embodiments have been described herein for purposes of illustration, but that various modifications may be made without deviating from the technology. Further, while advantages associated with certain embodiments of the technology have been described in the context of those embodiments, other embodiments may also exhibit such advantages, and not all embodiments need necessarily exhibit such advantages to fall within the scope of the technology. Accordingly, the disclosure and associated technology can encompass other embodiments not expressly shown or described herein.