Prosthetic finger and actuator

Abstract

Features for prosthetic fingers and actuation systems, including transmission features that rotate a worm gear via a leadscrew. Keyed members such as a central shaft are spring biased and transmit rotation from the worm gear to the finger while allowing the finger to be manually rotated without damaging the worm gear or other components. In some embodiments, the finger can include flexible links to cause rotation of the phalange segments while absorbing impacts or other high rotational loads. The finger can include a single-sided drive mechanism, with the opposite side providing support in the event of high lateral loads. The finger can include parallel motors and gearboxes that are mechanically connected through a transmission gearbox. The finger can include variable speed and variable torque gearboxes.

Description

[0001] Any priority application is incorporated by reference

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 902,227, filed September 18, 2019, entitled “PROSTHETIC DIGIT ACTUATORS WITH GEAR SHIFTING,” the entire contents of which are incorporated by reference herein for all purposes and made a part of this specification. BACKGROUND

[0003] TECHNICAL FIELD

[0004] Features of prosthetics are described, particularly prosthetic digits.

[0005] DESCRIPTION OF THE RELATED ART

[0006] Prosthetic digits are useful for amputees who lack a natural digit. Existing prosthetic digit solutions do not adequately mimic natural digits, and therefore do not fully restore functionality. Accordingly, improvements to prosthetic digits are needed. SUMMARY

[0007] The embodiments disclosed herein each have several aspects, no single one of which is solely responsible for the overall usefulness of this disclosure. Without limiting the scope of this disclosure, its more prominent features will now be discussed briefly. Considered in this discussion will be the interrelation of the various features of the embodiments as they affect the various embodiments. It is to be understood that other features and aspects of the disclosed embodiments can be utilized without affecting the overall usefulness of this disclosure.

[0008] The following disclosure describes non-limiting examples of some embodiments. For example, other embodiments of the disclosed systems and methods can include or exclude features described herein. Moreover, the disclosed advantages and benefits can apply only to certain embodiments of the invention and should not be used to limit the present disclosure.

[0009] Features of prosthetic digit drives are described. The digit can include a rigid link with a flexible portion. The flexible portion can be a bend at a distal end thereof. The link can transmit rotational force to various segments of the digit to open and close the digit. Flexibility of the link can absorb loads that exceed a threshold to absorb forces and reduce the risk of damaging the digit and actuator.

[0010] The finger can include a unilateral drive transmission on the lateral side of the finger. The actuation force can be transmitted from the actuator to the link through the unilateral side of the finger. The opposite side of the finger can include a support feature to assist with lateral loads exceeding a threshold, preventing damage to the finger and actuator in such cases. The support side can include two opposing surfaces with a gap,

[0011] Under high lateral loads, the gap closes and the surfaces contact each other to introduce a frictional rotational resistance to the finger and prevent damage.

[0012] The finger can include a compact actuator with a motor and gearbox positioned parallel to each other. The motor and gearbox can be located at or near the proximal joint of the prosthetic finger, or in the hand, and extend parallel to each other and parallel to the proximal segment of the finger. One or more transmission gears are arranged perpendicular to the motor and gearbox, which can transmit rotational force from the motor to the gearbox.

[0013] In another aspect, a prosthetic finger is described, including a mount, a proximal segment, a medial segment, a distal segment, a link, and an actuator. The mount is configured to attach to a hand. The proximal segment is rotatably attached to the mount, and the medial segment is rotatably attached to the proximal segment and the distal segment. The proximal segment has a drive side configured to be actuated to rotate the proximal segment. The proximal segment has a support side configured to provide rotational resistance to the finger in response to a threshold lateral load applied to the finger. The link is rotatably attached to the mount and rotatably attached to the medial segment. The link includes a flexible portion at a distal portion thereof. The link is configured to flex in response to a threshold rotational force applied to the finger. The actuator is coupled with the mount. The actuator is configured to rotate the proximal segment through the drive side. The actuator includes a motor and a gearbox that are parallel and mechanically connected through one or more transmission gears.

[0014] In another aspect, a prosthetic finger is described that includes a mount, a proximal segment, a middle segment, a distal segment, a linkage, and an actuator. The mount is configured to attach to a hand. The proximal segment is rotatably attached to the mount. The middle segment is rotatably attached to the proximal segment and the distal segment. The proximal segment has a drive side configured to transmit actuation to the proximal segment. The proximal segment has a support side configured to provide support to the finger in response to a threshold lateral load applied to the finger. The support side includes a first opposing surface spaced apart from a second opposing surface by a gap therebetween. Under a lateral load applied to the finger that exceeds the threshold lateral load, the proximal segment is configured to laterally flex to close the gap such that the first opposing surface and the second opposing surface contact each other and increase rotational friction of the finger. The linkage is rotatably attached to the mount and rotatably attached to the middle segment. The linkage includes a flexible portion. The actuator is coupled with the mount. The actuator is configured to rotate the proximal segment through the drive side. The actuator includes a motor and a gearbox that are parallel and mechanically connected by one or more transmission gears.

[0015] In another aspect, a prosthetic finger is described that includes a mount, a proximal segment, a middle segment, a distal segment, a linkage, and an actuator. The mount is configured to attach to a hand. The proximal segment is rotatably attached to the mount. The middle segment is rotatably attached to the proximal segment and the distal segment. The proximal segment has a drive side configured to be actuated to rotate the proximal segment. The proximal segment has a support side configured to provide rotational resistance to the finger in response to a threshold lateral load applied to the finger. The linkage is rotatably attached to the mount and the middle segment. The linkage includes a flexible portion and is configured to flex in response to a threshold rotational force applied to the finger; the actuator is coupled with the mount. The actuator is configured to rotate the proximal segment through the drive side. The actuator includes a motor that extends parallel to a planetary gearbox. An output shaft of the motor is mechanically connected to the planetary gearbox by a series of transmission gears that are located at a first end of the motor and the planetary gearbox and extend perpendicular to the motor and the planetary gearbox.

[0016] Various embodiments of each of the aspects can be implemented. For example, the linkage can further include a proximal linkage and a distal linkage. The distal linkage can include the flexible portion. The distal linkage can be rotatably attached to the proximal linkage and the distal segment. The proximal linkage can include a turn. Rotation of the proximal segment causes the proximal segment, the middle segment, and the distal segment to rotate simultaneously.

[0017] In some embodiments, the actuator can further include a tension spring and a worm gear. The tension spring is configured to rotationally bias the worm gear in an angular direction.

[0018] In some embodiments, the prosthetic finger can further include a thrust bearing. The thrust bearing can be configured to provide the rotational resistance in response to the threshold lateral load applied to the finger. The thrust bearing can be configured to provide rotational motion while bearing axial forces. The thrust bearing can include a second opposing surface.

[0019] In some embodiments, the prosthetic finger can further include an elastomeric fingertip insert. The fingertip insert can be configured to be connected to the distal segment. At least a portion of the insert is electrically conductive.

[0020] In some embodiments, a longitudinal axis of the motor extends parallel to a longitudinal axis of the gearbox. The longitudinal axis of the motor extends perpendicular to a longitudinal axis of the transmission gearbox housing the series of transmission gears.

[0021] In another aspect, features of a variable speed gearbox for a prosthetic finger actuator are described. The gearbox shifts gears to adjust the speed and torque output of the motor. The gearbox allows for two or more combinations of output speed and torque. A shift ring is adjusted to selectively engage and / or disengage two or more stages of the gearbox. These stages can be planetary gears or harmonic drives. The motor provides a rotational output to an output shaft mechanically connected to the prosthetic finger through the engaged stages. The shifting can be automatic based on mechanical and / or electronic feedback from the system. Axial force feedback can be provided, for example from a worm gear and worm screw set using a thrust stop that moves in response to a threshold value of axial force to cause a shift in gear. Torque output feedback can be provided, for example by an electronic sensor that causes an electronic actuator to cause a shift in gear.

[0022] The gearbox can be incorporated into various prosthetic fingers, such as a finger with multiple articulating finger segments, a compact linear or rotary actuator, one or more rigid links, one or more tendons, and / or an expandable link. An example finger using the gearbox mimics a natural finger through three articulating finger segments, including a proximal segment, a middle segment, and a distal segment. The segments are articulated by an actuator and mechanical links configured to cause segment rotation. The finger can have multiple degrees of freedom. A single actuator can be used for a single finger. Tendons can be used in certain variations. A rotary finger can provide articulation that mimics a natural finger, fully encompassing objects of various shapes and sizes, providing restored and enhanced gripping functionality for amputees. The finger can save space, weight, and power due to the need for only a single actuator. These and other prosthetic fingers can use the gearbox described herein. A spring-biased worm gear transmission can provide a manual mode for rotation of the finger and prevent damage from rotation due to external forces acting on the finger.

[0023] In one aspect, a prosthetic finger is described. The prosthetic finger includes a mount, a proximal segment, a middle segment, a distal segment, a proximal link, a distal link, and an actuator. The mount is configured to attach to a hand. The proximal segment is rotatably attached to the mount at a first pivot, and the middle segment is rotatably attached to the proximal segment and the distal segment. The proximal link is rotatably attached to the mount and rotatably attached to the middle segment at a second pivot. The distal link is rotatably attached to the proximal link and rotatably attached to the distal segment at a third pivot. The actuator is coupled with the mount and the proximal segment, and the actuator is configured to rotate the proximal segment about the first pivot, wherein rotation of the proximal segment about the first pivot causes the middle segment and the distal segment to rotate.

[0024] In another aspect, a prosthetic finger is described. The prosthetic finger includes a mount, a plurality of articulating segments including a proximal articulating segment, and an actuator. The mount is configured to attach to a hand. The proximal segment is rotatably attached to the mount at a first pivot and rotatably attached to the actuator at a first joint. The first joint is positioned offset from the first pivot such that linear actuation by the actuator output exerts a force at the first joint to rotate the proximal segment about the first pivot.

[0025] In another aspect, a prosthetic hand including a prosthetic finger is described.

[0026] In another aspect, a prosthetic finger is described. The prosthetic finger includes a mount, a proximal segment, a middle segment, a distal segment, a proximal expandable link, and an actuator. The mount is configured to attach to a hand. The proximal segment is rotatably attached to the mount, and the middle segment is rotatably attached to the proximal segment and the distal segment. The proximal expandable link is rotatably coupled with the mount and is configured to linearly expand such that the middle segment and the distal segment can rotate independently of rotation of the proximal segment. The actuator is mechanically coupled with the middle segment and the distal segment and is configured to rotate the middle segment and the distal segment. In some embodiments, the actuator is mechanically coupled with the proximal segment by a tendon.

[0027] In another aspect, an actuator for a prosthetic finger is described. The actuator includes a gearbox, a motor, a shaft, a lead screw, and a housing. The motor is mechanically coupled with the gearbox. The shaft extends axially distally from the gearbox. The lead screw is coupled to the shaft and has an external thread. The motor is configured to rotate the lead screw in a first rotational direction. The housing is configured to couple with the prosthetic finger. The housing has an internal thread configured to engage the external thread of the lead screw. Rotation of the lead screw causes the housing to translate axially relative to the lead screw, thereby causing the prosthetic finger to rotate.

[0028] In another aspect, a prosthetic finger is described that includes an actuator having a mount, a motor, a lead screw, and a housing. The mount is configured to attach to a hand. The motor is supported by the mount. The lead screw is coupled with the motor and has an external thread. The motor is configured to rotate the lead screw about a first axis. The housing extends along the first axis and is configured to connect with a proximal end of the prosthetic finger. The housing defines an internal cavity having an internal thread that engages the external thread of the lead screw. Rotation of the lead screw causes the housing to translate along the first axis, thereby causing the prosthetic finger to rotate.

[0029] In another aspect, a prosthetic finger includes a base, a proximal segment, a middle segment, a distal segment, an actuator, a wheel, a tendon, a tendon guide, and an expandable link. The base is configured to attach to a prosthetic hand. The proximal segment is rotatably attached to the base. The middle segment is rotatably attached to the proximal segment and the distal segment. The actuator is coupled with the base. The wheel is in mechanical connection with the actuator. The actuator is configured to rotate the wheel about a first axis. The tendon is connected with the wheel and extends distally from the wheel. The tendon guide is coupled with the prosthetic finger and the tendon extends along the tendon guide. The expandable link extends from a proximal end to a distal end. The proximal end is rotatably attached to the base about the first axis and the second end is rotatably attached to the middle segment. The actuator is configured to rotate the wheel in a first rotational direction, thereby pulling the tendon proximally, causing the distal segment to rotate relative to the middle segment in the first rotational direction. The distal end of the expandable link is configured to extend distally relative to the proximal end of the expandable link, thereby allowing the middle segment and the distal segment to rotate independently of rotation of the proximal segment.

[0030] In another aspect, a gearbox for a prosthetic finger actuator is described. The gearbox includes a housing, an output shaft, a first gear stage, a second gear stage, a third gear stage, and a shift ring. The housing extends from a proximal end to a distal end, and the proximal end is configured to couple with a motor. The output shaft extends distally from the distal end of the housing. The first gear stage is positioned within the housing and is configured to be in mechanical connection with the motor. The second gear stage is positioned within the housing distally of the first gear stage and is configured to be in mechanical connection with the first gear stage. The third gear stage is positioned within the housing distally of the second gear stage and is configured to be in mechanical connection with the second gear stage and the output shaft. The shift ring is positioned within the housing and is configured to move axially between a first axial position and a second axial position. In the first axial position, the shift ring is configured to, in response to actuation of the motor, engage the output shaft and the third gear to cause a first rotation of the output shaft having a first torque and a first speed. In the second axial position, the shift ring is configured to, in response to actuation of the motor, disengage the output shaft and engage the second and third gear stages to cause a second rotation of the output shaft having a second torque and a second speed.

[0031] Various embodiments of various aspects can be implemented. The first and second gear stages can each include a sun gear and a plurality of planet gears. The third gear stage can include a plurality of planet gears. The shift collar can be configured to engage the plurality of planet gears of the third gear stage.

[0032] In another embodiment, in the first axial position, the shift collar, the third gear stage, and the output shaft can be rotationally locked together. The shift collar can further include one or more protrusions extending distally, and the output shaft can include one or more splines. In the first axial position, the one or more protrusions can be received into the one or more splines such that the shift collar, the third gear stage, and the output shaft are rotationally locked together.

[0033] In another embodiment, the gearbox can further include a ring gear. The second gear stage can be configured to be mechanically connected to the first gear stage through the ring gear. In the second axial position, the shift collar can be configured to be mechanically connected to the second gear stage through the ring gear.

[0034] In another embodiment, the shift collar can further include one or more first protrusions extending proximally, and the ring gear can include one or more second protrusions extending distally. In the second axial position, the one or more first protrusions can engage the one or more second protrusions such that the shift collar is mechanically connected to the second gear stage through the ring gear.

[0035] In another embodiment, the gearbox can further include a thrust stop positioned along the output shaft. The thrust stop can be configured to move axially in response to a threshold axial force being applied to the thrust stop as a result of articulation of a joint of the prosthetic finger. The axial movement of the thrust stop can cause the shift collar to move axially between the first and second axial positions.

[0036] In another embodiment, the gearbox can further include an actuator configured to move the shift collar axially between the first and second axial positions in response to receiving a signal from a torque sensor indicating a threshold torque acting on the output shaft.

[0037] In another aspect, another gearbox for a prosthetic finger actuator is described. The gearbox includes one or more first gear stages configured to be mechanically coupled with an electric motor; a second gear stage configured to be mechanically coupled with one of the one or more first gear stages; an output shaft configured to be mechanically coupled with the second gear stage; and a shift collar configured to be axially moved between a first axial position and a second axial position. In the first axial position, the shift collar is configured to cause a first rotation of the output shaft in response to actuation of the electric motor. In the second axial position, the shift collar is configured to cause a second rotation of the output shaft in response to actuation of the electric motor, the first rotation having a different speed or torque than the second rotation.

[0038] In another embodiment, the one or more first gear stages can include two first gear stages. Each of the one or more first gear stages can include a sun gear and a plurality of planet gears.

[0039] In another embodiment, in the first axial position, the shift collar is configured to engage the output shaft and the second gear stage to cause the first rotation of the output shaft. In the second axial position, the shift collar is configured to disengage the output shaft and engage the second gear stage and the one of the one or more first gear stages to cause the second rotation of the output shaft.

[0040] In another embodiment, the gearbox can further include a ring gear configured to be mechanically coupled with the one of the one or more first gear stages. The second gear stage can be configured to be mechanically coupled with the one of the one or more first gear stages through the ring gear.

[0041] In another embodiment, the gearbox can further include a thrust stop positioned along the output shaft. The thrust stop can be configured to be axially moved in response to a threshold axial force applied to the thrust stop as a result of articulation of the prosthetic finger. The axial movement of the thrust stop can cause the shift collar to be axially moved between the first and second axial positions.

[0042] In another embodiment, the gearbox can further include an actuator configured to cause the shift collar to be axially moved between the first and second axial positions in response to receiving a signal from a torque sensor indicating a threshold torque acting on the output shaft.

[0043] In another embodiment, the shift collar can be configured to be manually moved between the first and second axial positions.

[0044] In another aspect, a mechanical method of shifting gears for a prosthetic finger actuator is described. The method includes moving a prosthetic finger joint to apply an axial force to a thrust stop, adjusting an axial position of the thrust stop along a rotatable output shaft in response to the axial force exceeding a threshold axial force, and adjusting an axial position of a shift ring in response to the adjusting the axial position of the output shaft, thereby changing a torque and speed output by the rotatable output shaft.

[0045] In some embodiments, the prosthetic finger further includes a distal link rotatably connected with the proximal expandable link and the distal segment.

[0046] In some embodiments, the proximal expandable link includes a proximal portion, a distal portion, and a spring, wherein the proximal portion is mechanically connected with the distal portion by the spring.

[0047] In another aspect, a prosthetic finger is described that includes a mount, a plurality of jointed segments, and an actuator. The mount is configured to attach to a hand. The plurality of jointed segments includes a proximal segment. The proximal segment is rotatably attached to the mount at a first pivot, the proximal segment is rotatably attached to the actuator at a first joint, and the first joint is positioned offset from the first pivot such that a linear actuation output by the actuator exerts a force at the first joint to rotate the proximal segment about the first pivot. BRIEF DESCRIPTION OF DRAWINGS

[0048] FIGS. 1A-1B are side and front views, respectively, of a lower arm residual limb having an embodiment of a prosthetic finger attached thereto, which can be any of the prosthetic fingers described herein.

[0049] FIGS. 2A-2B are rear and front views, respectively, of a prosthetic hand including an embodiment of a prosthetic finger, which can be any of the prosthetic fingers described herein.

[0050] FIGS. 3A-3D are various views of an embodiment of a prosthetic finger having jointed proximal, middle, and distal segments and mechanically connected rigid links, which can be used with FIGS. 1A-1B a lower arm residual limb of FIGS. 2A-2B a prosthetic hand of

[0051] FIG. 3E is a partial exploded perspective view of the prosthetic finger of FIGS. 3A-3D

[0052] FIGS. 3F-3H are sequential views of the prosthetic finger of FIGS. 3A-3D illustrated in various rotational configurations, in which the middle and distal segments rotate with the proximal segment as it rotates due to the interaction of the links.

[0053] FIGS. 4A-4D ​are various views of another embodiment of a prosthetic finger having articulating proximal, middle, and distal segments and an expandable proximal link that can be used with FIGS. 1A-1B a lower arm stump or FIGS. 2A-2B a prosthetic hand of

[0054] FIGS. 5A-5E are various views of an expandable link for use in a prosthetic finger of FIGS. 4A-4D

[0055] FIGS. 6A-6D are sequential views of a prosthetic finger of FIGS. 4A-4D shown in various rotational configurations, where the middle and distal segments rotate with rotation of the proximal segment due to interaction of the links.

[0056] FIGS. 7A-7D are sequential views of a prosthetic finger of FIGS. 4A-4D shown in various rotational configurations, where the middle and distal segments rotate independently of rotation of the proximal segment due to interaction of the links.

[0057] FIGS. 8A-8B are sequential views of an embodiment of an actuator that can be used in any of the prosthetic fingers described herein, where the housing translates axially relative to the lead screw.

[0058] FIG. 8C are cross-sectional views of the actuator taken along lines 8C-8C shown in FIG. 8A

[0059] are sequential views of another embodiment of an actuator that can be used in any of the prosthetic fingers described herein, where the housing translates axially relative to the lead screw. FIGS. 9A-9B

[0060] and FIG. 9C are two cross-sectional views of the actuator taken along lines 9C-9C shown in 9D FIG. 9A and FIG. 9C are rotated 90 degrees relative to each other. 9D

[0061] are various views of an embodiment of a prosthetic finger having articulating proximal, middle, and distal segments and a mechanically linked rigid link that can be used with FIGS. 10A-10C a lower arm stump or FIGS. 1A-1B a prosthetic hand of FIGS. 2A-2B

[0062] FIG. 11A are perspective views of another embodiment of an actuator having three gear stages that can be used in any of the prosthetic fingers described herein.

[0063] FIG. 11B are​​​FIG. 11A Exploded view of actuator of

[0064] FIG. 11C FIG. 11A Side view of actuator of

[0065] FIG. 11D FIG. 11C Partial cutaway view of actuator of FIG. 11A

[0066] FIG. 11E FIG. 11C Partial cutaway view of actuator of FIG. 11A

[0067] FIG. 12

[0068] FIG. 13

[0069] FIG. 14

[0070] FIG. 15

[0071] FIGS. 16A-16C

[0072] FIGS. 17A-17C

[0073] FIGS. 18A-18C

[0074] FIGS. 19A-19E

[0075] ​​​​​​​​​​​​​FIGS. 20A-20C is a schematic diagram of a three-speed gearbox with switchable multi-speed ratios with first order shifting.

[0076] FIGS. 21A-21C is a schematic diagram of a multi-speed ratio gearbox composed of strain wave stages and switchable planetary stages.

[0077] FIG. 22 is a schematic diagram showing an embodiment of a control system for various actuators described herein.

[0078] FIG. 23 is a flowchart depicting an embodiment of a method of controlling a motor during shifting.

[0079] FIG. 24 is a data plot depicting an embodiment of input torque and output torque response of a two-speed gearbox.

[0080] FIG. 25 is a data plot illustrating a shift force hysteresis designed to suppress speed ratio hunting.

[0081] FIG. 26 is a flowchart showing an embodiment of a method of shifting with a prosthetic finger actuator.

[0082] FIG. 27 is a flowchart showing another embodiment of a method of shifting with a prosthetic finger actuator.

[0083] FIGS. 28A-28B are cross-sectional and exploded views, respectively, of another embodiment of a prosthetic finger actuator including a gear synchronization.

[0084] FIG. 29A shows a cross-sectional close-up view of a mechanism for synchronizing a gear.

[0085] FIGS. 29B-29D shows FIG. 28A the sequential steps of an actuator in synchronizing a shift ring and an output shaft.

[0086] FIG. 30A shows a cross-sectional view of a portion of an actuator of the friction synchronization component shown in FIG. 28A

[0087] shows FIGS. 30B-30D the sequential steps of an actuator in FIG. 28A synchronizing a shift ring and a ring gear.

[0088] FIGS. 31A-31C depicts three examples of stopper profiles and resulting force versus displacement plots.

[0089] FIGS. 32A-32Bare perspective and sectional views of another embodiment of a prosthetic finger having proximal, middle, and distal segments that are articulated.

[0090] FIGS. 33A-33C is FIGS. 32A-32B various views of an actuator of a prosthetic finger of

[0091] FIG. 34 is FIGS. 33A-33C a perspective view of an actuator of

[0092] FIG. 35 is FIGS. 32A-32B a sectional view of a portion of a prosthetic finger of

[0093] FIGS. 36A-36B are side and sectional views of another embodiment of a prosthetic finger having proximal, middle, and distal segments that are articulated.

[0094] FIGS. 37A-37C are perspective views of a link and an actuator, an exploded view of the link, and FIGS. 36A-36B a sectional view of an actuator of a finger of

[0095] FIGS. 38A-38C are sequential views of a prosthetic finger of FIGS. 36A-36B in various rotational configurations, in which the middle and distal segments rotate with the proximal segment due to interaction of the links.

[0096] FIGS. 39A-39B are portions of a proximal segment and an exploded view of a mount of a prosthetic finger of FIGS. 36A-36B configured to engage an actuator.

[0097] FIG. 40A is FIGS. 36A-36B a sectional top view of a prosthetic finger of

[0098] FIGS. 40B-40D is FIGS. 36A-36B various views of a proximal segment of a prosthetic finger of

[0099] FIGS. 40E-40F schematically illustrates FIGS. 36A-36B an unloaded and a loaded configuration of a prosthetic finger of

[0100] FIGS. 41A-41B are various views of an actuator of a prosthetic finger of FIGS. 36A-36B illustrating a motor, a gearbox, and a drive gear.

[0101] FIGS. 42A-42C is FIGS. 36A-36B Various views of a fingertip assembly of a prosthetic finger showing a removable fingertip insert.

[0102] The foregoing and other features of the present disclosure will become more apparent from the following description and accompanying drawings. It is understood that the drawings are only schematic and that actual implementations can differ from the specific illustrations. It is also understood that the illustrative implementations described in the detailed description and illustrated in the accompanying drawings are not meant to be limiting. Other implementations can be utilized, and other changes can be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the Figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and form part of this disclosure. DETAILED DESCRIPTION

[0103] The following detailed description is directed to certain specific embodiments of the invention. In this description, reference is made to the drawings wherein like numbers indicate like parts throughout the several views. The following description of the embodiments is not meant to limit the application in any way. In the description, reference is made to the drawings, where like numerals indicate like parts throughout the several figures. The reference numerals in the following description are by way of illustration of embodiments in which the application can be practiced. Each of the following embodiments can be implemented in hardware, software, or both. The various embodiments of the application can be realized in a centralized fashion in one industrial-scale computer or other hardware, or in a distributed fashion where different elements are spread across several industrial-scale computers or other hardware. Any kind of computer system, or other apparatus adapted for carrying out the methods described herein, is suited. A typical combination of hardware and software could be a general purpose computer system with a computer program that, when being loaded and executed, carries out the methods described herein. Alternatively, a custom-made hardware and / or software system can be created for use with the application. The application can also be embedded in a computer program product, which comprises all the features enabling the implementation of the methods described herein, and which, when being loaded in a general purpose computer system or other apparatus and executed, carries out these methods.

[0104] Prosthetic fingers are described. These fingers have three jointed segments to mimic a natural finger, including a proximal segment, a middle segment, and a distal segment. The segments are jointed through actuators and rotatably connected mechanical linkages configured to cause and / or induce rotation of the finger segments. Certain variants can use one or more tendons to apply opening and closing forces to the finger. Other variants can not require tendons to achieve articulation of the segments. Rotation of the proximal segment causes rotation of the middle and distal segments through mechanical interaction of the linkages. There can be a proximal linkage and a distal linkage. The finger can have an actuator whose output is linear actuation to cause rotation of the proximal segment and / or the proximal linkage. The actuator can be a linearly translating housing that is rotatably connected to the proximal segment at a joint. The housing pushes the proximal segment at the joint to create a torque about an offset pivot on the segment. The pivot can be a pin that attaches the proximal segment to the proximal linkage. The pivot is located at a position offset from the joint. In some embodiments, the proximal linkage can be linearly extendable and retractable to allow variable relative rotational positions of the finger segments. The distal finger segment can rotate independently of rotation of the proximal finger segment. The finger can thus have multiple degrees of freedom with only a single actuator. The rotating finger can provide articulation that mimics a natural finger, fully encompassing both large and small objects, providing and restoring enhanced grasping functionality to amputees. Because only a single actuator is required, the finger can save space, weight, and power. The segments can provide movements similar to movements of individual human phalangeal bones in a healthy natural finger.

[0105] In some embodiments, the finger includes a transmission feature for worm rotation through a lead screw. A keyed member such as a central shaft is spring biased and transmits rotation from the worm to the finger while allowing manual rotation of the finger without damaging the worm or other components. In some embodiments, the finger can include flexible linkages to cause rotation of the finger segments while absorbing impacts or other high loads. The finger can include a single-sided drive mechanism, with the opposite side providing support in the event of high lateral loads. The finger can include parallel motors and gearboxes and be mechanically connected through one or more transmission gears. Any feature described in any embodiment described herein can be used with any other embodiment. For example, with reference to FIGS. 1A-31C Any feature of the described fingers or components thereof can be used with FIGS. 32A-42C Any finger or component thereof described can be used with any other finger or component thereof described, and vice versa.

[0106] FIGS. 1A-1B are a side view and a front view, respectively, of a lower arm prosthetic system 100 including a lower arm residual limb 112 having four prosthetic fingers 120 and a prosthetic thumb 130 attached to the residual limb 112. FIG. 1A is a side view of the system 100. FIG. 1Bis a front or palmar side view of the system 100. The prosthetic fingers 120 and / or the prosthetic thumb 130 can be any of the prosthetic fingers described herein. As shown, the prosthetic fingers 120 can be connected to the end of the lower arm residual limb 112, or as shown, to the remaining natural hand palm 114. FIG. 1A FIG. 1B

[0107] As shown, the fingers 120 and the thumb 130 are grasping an object 140, which is shown as a circular object, such as a can or a ball. The fingers 120 wrap around the object 140 so that the object 140 can be securely held by the system 100. The rotatable ability of the segments of the fingers 120 allows for such secure grasping. The shape of the object 140 has a width and profile that allows the jointed fingers 120 to provide secure grasping. The fingers 120 have various jointed segments that can rotate at various angles relative to adjacent segments. In some embodiments, the segments can rotate accordingly at fixed angular relationships so that only certain sizes and shapes of objects 140 can be securely grasped. In some embodiments, the segments can rotate accordingly at variable angular relationships so that only different sizes and shapes of objects 140 can be securely grasped. FIG. 1A

[0108] FIGS. 2A-2B are a rear and front view, respectively, of a prosthetic hand 200 including an embodiment of a prosthetic finger 220 and a prosthetic thumb 230. The hand 200 has a palm portion 252 attached to the proximal ends of the fingers 220 and the thumb 230. The hand 200 can have a wrist 254 that can rotate, which can allow the palm portion 252 and the fingers 220 and the thumb 230 attached to the palm portion 252 to rotate about a longitudinal axis defined by the wrist 254. The prosthetic finger 220 can be any of the prosthetic fingers described herein. As described with respect to the system 100 of FIGS. 1A-1B the prosthetic finger 220 can rotate according to fixed or variable angular relationships between the jointed finger segments.

[0109] FIGS. 3A-3D are various views of an embodiment of a prosthetic finger 300. The finger 300 can be used with the system 100 or the hand 200. The finger 300 includes an actuator 301, a mount 350, a proximal segment 320, a middle segment 330, and a distal segment 340. The segments can articulate, such as rotate, relative to one another. As further described herein, for example with respect to the system 100 of FIGS. 3D-3G the finger 300 includes a mechanically linked linkage, which can be rigid. The segments 320, 330, 340 can provide natural movement similar to that provided by the proximal, middle, and distal phalangeal bones, respectively, of a healthy natural finger.

[0110] ​​​Mounting element 350 and / or actuator 301 may be partially or completely connected to and / or located therein with the arm stump 112, the residual hand 114, or the prosthetic hand 252. Proximal segment 320 may rotate relative to mounting element 350 and / or actuator 301. Mid-segment 330 may rotate relative to proximal segment 320. Distal segment 340 may rotate relative to mid-segment 330.

[0111] like FIG. 3B As shown, actuator 301 includes a proximal end 313 and extends to a distal end 317. The proximal end 313 can be attached to a hand, palm, etc. The distal end 317 is attached to the proximal end 321 of proximal segment 320. Proximal segment 320 is rotatable relative to actuator 301 about joint 318. As further described herein, actuator 301 can apply a normal force at joint 318 to proximal segment 320 to pivot proximal segment 320 about a first offset pivot 356. Proximal segment 320 extends from proximal end 321 to distal end 327. Distal end 327 is connected to the proximal end 331 of intermediate segment 330. Intermediate segment 330 is rotatable relative to proximal segment 320 about joint 328. Intermediate segment 330 extends from proximal end 331 to distal end 337. Distal end 337 is attached to the proximal end 341 of distal segment 340. Distal segment 340 is rotatable relative to intermediate segment 330 about joint 338. The rotatable connection at joints 318, 328, and 338 may include a pin connection, a hinge, and / or other suitable features for providing rotatable engagement.

[0112] FIG. 3D It is along FIG. 3C The 3D-3D cutaway view of the finger at angle 300, as indicated by the line in the diagram. FIG. 3D As shown, finger 300 may include actuator 301. Actuator 301 may be a linear actuator. Actuator 301 generates or causes linear motion. As shown, actuator 301 may include motor 305, which is powered by a battery located on the hand or other location. Support 310, such as a motor mount or other structure, may carry or otherwise support actuator 301. Support 310 may have pin 302 or other suitable features at its proximal end to secure support 310 to, for example, rotatably attach it to mount 350.

[0113] Actuator 301 includes a housing 311. Housing 311 extends axially and defines a cavity 315 therein. Cavity 315 may be a cylindrical opening extending axially through housing 311. A proximal end of housing 311 may communicate with cavity 315. A distal end of housing 311, for example at distal end 317 of actuator 301, is connected to proximal segment 320 at joint 318. As further described herein, axial translation of housing 311 causes rotation of proximal segment 320.

[0114] The motor 305 (e.g., a stationary portion thereof) can be supported by the support 310. There can be a bushing 306 that rotationally supports a rotating portion of the motor 305, which can be located within and / or supported by the support 310. The motor 305 can include a shaft 307 extending therefrom, e.g., distally therefrom, about which the shaft 307 extends. A cap 308, such as a nut, can be attached to a distal end of the shaft 307. A lead screw 314 having external threads 319 thereon can be positioned about the shaft 307 and secured in place by the cap 308. The lead screw 314 can be a nut having external threads or other suitable features that engage corresponding internal structures of the housing 311 to translate the housing 311 back and forth.

[0115] As further described, the actuator 301 can output linear motion to cause rotation of the finger 300. The motor 305 or other portions of the actuator 301 can use or provide rotational, linear, cyclical, and / or other types of motion. As shown, the actuator 301 is mechanically coupled with the lead screw 314 having external threads 319. The actuator 301 rotates the lead screw 314. The external threads 319 of the lead screw 314 are mechanically coupled with internal threads 316 of the housing 311. The internal threads 316 can be positioned along a cavity 315 of the housing 311. The housing 311 can be movable relative to the support 310. The lead screw 314 is rotated while remaining axially fixed to cause the housing 311 to translate axially along an axis defined by the cavity 315 by the interaction of the external threads 314 and the internal threads 316. Threaded engagement features and rotational motion of the actuator 301 is one example embodiment. Other features and / or actuator types can be used to output linear motion of the housing 311.

[0116] As the housing 311 is advanced distally and proximally, the actuator 301 can rotate about the pin 302 to accommodate the rotating proximal segment 320. For example, the joint 318 can translate slightly during rotation, and the distal end of the housing 311 can move accordingly such that the actuator 301 rotates slightly at the pin 302. The actuator 301 can rotate counterclockwise as oriented during distal movement of the housing 311 for closed rotational movement of the segments 320, 330, 340. The actuator 301 can rotate clockwise as oriented during proximal movement of the housing 311 for open rotational movement of the segments 320, 330, 340. FIG. 3D As the housing 311 is advanced distally and proximally, the actuator 301 can rotate about the pin 302 to accommodate the rotating proximal segment 320. For example, the joint 318 can translate slightly during rotation, and the distal end of the housing 311 can move accordingly such that the actuator 301 rotates slightly at the pin 302. The actuator 301 can rotate counterclockwise as oriented during distal movement of the housing 311 for closed rotational movement of the segments 320, 330, 340. The actuator 301 can rotate clockwise as oriented during proximal movement of the housing 311 for open rotational movement of the segments 320, 330, 340. FIG. 3D As the housing 311 is advanced distally and proximally, the actuator 301 can rotate about the pin 302 to accommodate the rotating proximal segment 320. For example, the joint 318 can translate slightly during rotation, and the distal end of the housing 311 can move accordingly such that the actuator 301 rotates slightly at the pin 302. The actuator 301 can rotate counterclockwise as oriented during distal movement of the housing 311 for closed rotational movement of the segments 320, 330, 340. The actuator 301 can rotate clockwise as oriented during proximal movement of the housing 311 for open rotational movement of the segments 320, 330, 340.

[0117] As the housing 311 is advanced distally and proximally, the actuator 301 can rotate about the pin 302 to accommodate the rotating proximal segment 320. For example, the joint 318 can translate slightly during rotation, and the distal end of the housing 311 can move accordingly such that the actuator 301 rotates slightly at the pin 302. The actuator 301 can rotate counterclockwise as oriented during distal movement of the housing 311 for closed rotational movement of the segments 320, 330, 340. The actuator 301 can rotate clockwise as oriented during proximal movement of the housing 311 for open rotational movement of the segments 320, 330, 340. FIG. 3DFurther shown, the finger 300 includes a mount 350, a proximal link 360, and a distal link 370. The mount 350 extends from a proximal end 352 to a distal end 354. The proximal link 360 extends from a proximal end 362 to a distal end 364. The distal link 370 extends from a proximal end 372 to a distal end 374.

[0118] The proximal end 352 of the mount 350 can be attached to the proximal end of the actuator 301, e.g., rotatably attached thereto. The mount 350, e.g., at the proximal end 352 and / or at other locations, can be attached to a hand, e.g., a prosthetic hand. Further details of the mount 350 will be described herein, e.g., with reference to FIG. 3H The distal end 354 of the mount 350 is rotatably attached to the proximal end 362 of the proximal link 360 about a connection 358. The mount 350 is also rotatably attached to the proximal segment 320 of the finger 300 about a first pivot 356. The first pivot 356 is located between the proximal end 352 and the distal end 354 of the mount 350.

[0119] The proximal link 360 is rotatably attached to the middle segment 330 of the finger 300 about a second pivot 366. The second pivot 366 is located between the proximal end 362 and the distal end 364 of the proximal link 360. The proximal link 360 can include a bend at which the proximal end 362 extends along a first axis and the distal end 364 extends along a second axis at an angle to the first axis. The second pivot 366 can be located at or near an apex of the bend of the proximal link 360. The distal end 364 of the proximal link 360 is rotatably attached to the proximal end 372 of the distal link 370 about a connection 368. The distal end 374 of the distal link 370 is rotatably attached to the distal segment 340 of the finger 300 about a third pivot 376.

[0120] In summary, the segments 320, 330, 340 are rotatably attached to the links 320, 330, 340, respectively, at the pivots 356, 366, 376, respectively. The segments 320, 330, 340 are rotatably attached to each other at the joints 318 and 328, the joint 318 rotatably connecting the proximal segment 320 to the middle segment 330, and the joint 328 rotatably connecting the middle segment 330 to the distal segment 340. The links 350, 360, 370 are rotatably attached to each other at the connections 358 and 368, the connection 358 rotatably connecting the mount 350 to the proximal link 360, and the connection 368 rotatably connecting the proximal link 360 to the distal link 370.

[0121] All or some of the rotatable connections at joints 318, 328, 338, at pivots 356, 366, 376, and at connections 358, 368 can include pins, hinges, and / or other suitable features for providing rotatable engagement. Axes of rotation of joints 318, 328, 338, pivots 356, 366, 376, and connections 358, 368 can be perpendicular to a longitudinal axis of finger 300. Such a longitudinal axis can be defined by a fully extended finger 300, for example as shown in FIG. 3F The longitudinal axis can be defined by a direction of linear movement provided by actuator 301, for example a direction of linear movement of lead screw 314. Axes of rotation of joints 318, 328, 338, pivots 356, 366, 376, and connections 358, 368 can be parallel to each other. Positions of joints 318, 328, 338, pivots 356, 366, 376, and connections 358, 368 can change with rotation of finger 300, for example some or all of these positions can change relative to support 310 and / or relative to mount 350.

[0122] FIG. 3E is a partial exploded perspective view of prosthetic finger 400. As shown, mount 350 includes an elongated proximal portion 351 that defines a cavity 353. Proximal end 352 includes a proximal wall 355 with an opening 302A extending through proximal wall 355. Pin 302 of support 310 can extend through opening 302A to rotatably connect actuator 301 and proximal end of mount 351. This allows actuator 301 to slightly rotate at the proximal end as needed for finger actuation. Mount 350 includes a series of tabs 351A to connect mount 350 to a hand, for example prosthetic hand 200 or palm 114. Mount 350 can be fixedly attached to the hand. As shown, there can be four tabs 351A, or more or less than four. Mount 350 includes two distally extending prongs 357. Prongs 357 extend from a distal end of portion 351. The two prongs 357 define a space between them that receives proximal portion of proximal segment 320. Prongs 357 include openings 357A that receive pivots 356 therein. Pivots 356 are shown as pins with rollers.

[0123] Mount 350 includes a prong 354A extending distally from the proximal end of portion 351. Prong 354A is located between prongs 357. Prong 354A is located at the proximal end 354 of mount 350. Prong 354A includes an opening 356A therethrough that receives a central portion of a pivot 356 therein. Pivot 356 can thus rotate within openings 356A, 357A, and / or provide an axis about which proximal segment 320 rotates. Prong 354A includes an opening 358A at its distal end. Opening 358A receives a connector 358 therein, shown as a pin. As described herein, connector 358 can thus rotate within opening 358A, and / or provide an axis about which proximal link 360 rotates.

[0124] Actuator 301 includes a joint 318, shown as a pin. Joint 318 is received into an opening 318A of proximal segment 320. Joint 318 can be a shear pin that is axially pushed by housing 311 to exert a force on proximal segment 320 at opening 318A. Joint 318 is offset from pivot 356. It will thus cause joint 318 to create a torque about pivot 356 on proximal segment. The axes of rotation of joint 318 and pivot 356 can be parallel to each other.

[0125] Middle segment 330 includes one or more openings 328A that receive a joint 328 therein. Joint 328 is shown as a pin. Joint 328 can thus rotate within opening 328A, and / or provide an axis about which proximal segment 320 and middle segment 330 rotate as described herein. Distal segment 340 includes one or more openings 338A that receive a joint 338 therein. Joint 338 is shown as a pin. Joint 338 can thus rotate within opening 338A, and / or provide an axis about which middle segment 330 and distal segment 340 rotate as described herein.

[0126] FIGS. 3F-3H are sequential views of prosthetic finger 300 shown in various rotational configurations. As used herein, “distal” and “proximal” have their usual and ordinary meanings. For clarity, the “distal” and “proximal” directions for a fully extended finger 300 are shown as FIG. 3F and generally refer to the direction or portion of finger 300 that is distal or proximal, respectively, to proximal end 352 of mount 350 along the length of finger 300. FIG. 3F An embodiment of a fully straightened finger 300 is shown. FIG. 3G An embodiment of a partially closed finger 300 is shown, FIG. 3H An embodiment of a fully closed finger 300 is shown.

[0127] As further described, middle segment 330 and distal segment 340 can rotate with proximal segment 320 as it rotates due to the interaction of mount 350 and links 360, 370. For example, asFIG. 3H As shown, the distal segment 340 can be fully closed such that the distal segment 340 is parallel or nearly parallel to the proximal segment 320. In some embodiments, the distal segment 340 can be rotated through this parallel position such that at full rotation the distal segment 340 is tilted back toward the middle segment 320. The distal segment 340 can contact the proximal segment 320 in the fully rotated configuration. This full or over- completed closure of the distal segment 340 provides advantageous grasping capabilities with the finger 300 and more fully restores the lost intact finger flexibility of a user (e.g., an amputee). The features described herein, such as the mounting 350, links 360, 370, and the configuration and interaction of the segments 320, 330, 340, among other things, contribute to these advantages.

[0128] To rotate the finger 300, the actuator 301 can rotate the threaded rod 314 having external threads. The external threads of the threaded rod 314 are mechanically coupled with the internal threads 316 of the housing 311. The actuator 301 can rotate the threaded rod 314 in a first rotational direction to move the housing 311 distally, e.g., translate, relative to the threaded rod 314. The threaded rod 314 can remain axially fixed. The housing 311 moves distally further in the sequence shown from FIGS. 3F to 3G to 3H. The rotational direction of the finger 300 can be reversed (e.g., as oriented in the figures) by the actuator 301 rotating the threaded rod 314 in a second rotational direction opposite the first rotational direction, thereby moving the housing 311 proximally, e.g., translate, relative to the threaded rod 314. FIGS. 3H to 3G to FIG. 3F .

[0129] The distal movement of the housing 311 moves the proximal end 321 of the proximal segment 320 distally through the rotatable connection at the joint 318. Due to the offset position of the joint 318 and the pivot 356, the distal movement of the proximal segment 320 at the joint 318 will cause the proximal segment 320 to rotate clockwise (as oriented in the figures) about the first pivot 356. The line of action of force is exerted on the proximal segment 320 extending through the joint 318, thus exerting a moment about the pivot 356 on the proximal segment 320. The clockwise rotation of the proximal segment 320 about the first pivot 356 causes the proximal segment 320 to rotate clockwise about the joint 318 relative to the housing 311. Thus, as shown in the sequence from FIGS. 3F to 3G to 3H, the proximal segment 320 rotates clockwise. To reverse the rotational direction in a counterclockwise direction (as oriented in the figures), these movements can be reversed, where the housing 311 moves proximally to move the proximal end 321 of the proximal segment 320 proximally and rotate in a counterclockwise direction about the first pivot 356 and the joint 318. As described herein, the pin joint or other type of connection at the joint 318 can allow this pushing and pulling force of the housing 311 to be transmitted to the proximal segment 320.

[0130] As the proximal segment 320 rotates clockwise about the pivot 356, the middle segment 330 also rotates clockwise with the rotating proximal segment 320 due to the connection of the two segments 320, 330 at the joint 328. In some embodiments, the middle segment 320 can be limited to rotate further in the counterclockwise direction. For example FIG. 3F The configuration shown can be the rotation limit of the middle segment 330 about the joint 328 relative to the proximal segment 320.

[0131] The rotation of the middle segment 330 also causes the distal segment 340 to rotate clockwise due to the connection of the two segments 330, 340 at the joint 368. In some embodiments, the distal segment 340 can be limited to rotate further in the counterclockwise direction, for example FIG. 3F The configuration shown can be the rotation limit of the distal segment 340 about the joint 338 relative to the middle segment 330.

[0132] As the middle segment 320 rotates clockwise, the proximal link 360 also rotates clockwise due to the connection of the middle segment 320 and the proximal link 360 at the second pivot 366. In addition, the proximal link 360 is constrained from translating by the mount 350 at the rotatable connection 358. The proximal link 360 thus rotates clockwise about the connection 358. The joint 328 is offset from the second pivot 366 as shown. Accordingly, a torque can be applied to the middle segment 320 about the pivot 366. The rotation axes of the joint 328 and the second pivot 366 can be parallel.

[0133] As the proximal link 360 rotates clockwise about the connection 358, this also causes the distal link 370 to rotate clockwise due to the translational constraint of the proximal link 320 and the distal link 330 at the rotatable connection 368. As the distal link 330 rotates clockwise, the distal segment 340 is constrained from translating by the distal link 330 at the third pivot 376. The distal segment 340 also rotates relative to the middle segment 330 about the rotatable connection at the joint 338. The joint 338 is offset from the third pivot 376 as shown. Accordingly, a torque can be applied to the distal segment 340 about the pivot 376. The rotation axes of the joint 338 and the third pivot 376 can be parallel. The distal segment 340 thus rotates further clockwise about the third pivot 376 to provide FIG. 3H The closure mechanism shown.

[0134] The finger 300 can be sequentially rotated in the counterclockwise direction in the configurations shown from FIGS. 3F to 3G to 3H. Counterclockwise rotation is opposite to the clockwise rotation described above. For example, proximal movement of the proximal end 321 of the proximal segment 320 pulls proximally at the joint 318 and causes the proximal segment 320 to rotate counterclockwise about the pivot 356, which causes the middle segment 330 and the proximal link 360 to rotate counterclockwise about the joint 328 and the pivot 366, respectively, which causes the distal segment 340 and the distal link 370 to rotate counterclockwise about the joint 338 and the pivot 376, respectively.

[0135] FIGS. 4A-4D are various views of another embodiment of a prosthetic finger 400. The finger 400 can be used with the system 100 or the hand 200. The finger 400 includes a mount 410, a proximal segment 420, a middle segment 430, and a distal segment 440. The mount 410 and the segments 420, 430, 440 can have the same or similar features and / or functions as the mount 350 and the segments 320, 330, 340, and thus can be articulatable relative to one another, e.g., rotatable. As described herein, e.g., with respect to the finger 300, the finger 400 can include a mechanical linkage of rigid links that includes an expandable proximal link 450. FIGS. 4D-7D As further described herein, the finger 400 includes a mechanical linkage of rigid links that includes an expandable proximal link 450.

[0136] The mount 410 and the segments 420, 430, 440 can be rotatably attached at joints 418, 428, 438, which can have the same or similar features and / or functions as the joints 318, 328, 338, respectively. However, the mount 410 can not have a linearly translatable portion. The finger 400 can have an actuator 404, which can have the same or similar features and / or functions as the actuator 301, unless otherwise noted.

[0137] FIG. 4D is a cross-sectional view of the finger 400 taken along the line 4D-4D shown in FIG. 4B. As shown in FIG. 4B, the mount 410 can support the actuator 404. The actuator 404 can include a housing 403 that extends proximally. The housing 403 can be used to house features for rotating the segments 420, 430, 440, e.g., a spring 486 that provides a force in the proximal direction on a plunger 481 attached to a proximal end 482 of a return tendon 480, as further described herein. Some embodiments can not include the return tendon 480. FIG. 4C FIG. 4D

[0138] ​​The actuator 404 can include a motor 405 powered by a battery that can be on the hand or elsewhere. The motor 405 can be in mechanical connection with an output shaft 409 extending distally therefrom, for example. A worm 414 having external threads 419 thereon can be attached to the shaft 409. Actuation of the motor 405 causes motion to be transmitted through a gearbox to the shaft 409 to rotate the worm 414. The finger 400 can include a worm gear 412 having external teeth 416 thereon. The threads 419 of the worm 414 contact the teeth 416 of the worm gear 412 to cause rotational motion of the worm gear 412 about a first axis. The worm gear 412 can be rotated about the first axis in a first rotational direction to cause a first rotation of the finger 400 in a first direction (e.g., closing the finger 400). As further described, the worm gear can have a pulley feature that is attached to and receives around a proximal end of an actuation tendon 470. As further described, the worm gear 412 can be rotated about the first axis in a second rotational direction opposite the first rotational direction to allow a second rotation of the finger 400 in a second direction opposite the first direction, which movement can be caused by a return tendon 480. Some embodiments can not include the actuation tendon 470 or the return tendon 480.

[0139] The finger 400 includes an expandable proximal link 450. The link 450 is attached to the worm gear 412. Rotation of the worm gear 412 in the first rotational direction by a first angular amount causes the link 450 to rotate in the first rotational direction by a corresponding first angular amount. The link 450 can expand. The link 450 or a portion thereof can extend distally relative to the worm gear 412. The link 450 includes a proximal end 452 and extends to a distal end 454. The proximal end 452 includes a fixed portion 451, such as a cylinder. The distal end 454 includes a housing 459, such as a piston. The link 450 can include a spring 456, such as a tension spring. Extension of the spring 456 beyond a neutral length can cause a restoring force that biases the spring back to a shorter length. The link 450 can expand upon rotation thereof to allow for multi-degree of freedom rotation of the finger 400. The housing 459 can expand distally relative to the fixed portion 451. The spring 456 can bias the housing 459 in a proximal direction. The housing 459 can retract in the proximal direction relative to the fixed portion 451. Further details of the link 450 are described herein, for example with respect to FIGS. 5A-5E

[0140] ​Link 450 is attached to middle segment 430 of finger 400. Distal end 454 of link 450 can be rotatably attached to middle segment 430 at connector 458. Middle segment 430 can include ears 432 that are rotatably connected with link 450. Connector 458 can include a pin or other feature that extends through link 450 and ears 432 at connector 458. Link 450 can extend between two ears 432, one ear 432 on either lateral side of distal end 454 of link 450 at connector 458.

[0141] Finger 400 can include a distal link 460. Distal link 460 extends from a proximal end 462 to a distal end 464. Proximal end 462 can be rotatably attached to ear 432 at connector 461. Ear 432 can include a circular slot 433. Connector 461 can include a pin or other feature that extends through link 460 and circular slot 433 at connector 461. As finger 400 articulates, connector 461 allows proximal end 462 of distal link 460 to rotate within and move along slot 433, for example as middle segment 430 rotates relative to proximal segment 420 and / or as distal segment 440 rotates relative to middle segment 430.

[0142] Distal link 460 is attached to distal segment 440. Distal end 464 of distal link 460 can be rotatably attached to distal segment 440 at connector 468. Connector 468 can include a pin or other component that extends through distal link 460 and distal segment 440 at connector 468. Distal segment 440 can include ears 442 that have openings therethrough and to which distal link 460 is attached. Distal end 464 of link 460 can extend between two ears 442, one ear 442 on either lateral side of distal end 464 of link 460 at connector 468.

[0143] FIGS. 5A-5E is a perspective view of proximal expandable link 450. FIG. 5A is a perspective view of link 450. FIG. 5B is a top view. FIG. 5C is a side view of the unexpanded configuration mechanism. FIG. 5D is a side view of the expanded configuration, FIG. 5D is a side view of the expanded configuration. FIG. 5E is a cross-sectional view taken along FIG. 5B line 5E-5E shown.

[0144] The proximal link 450 can include extensions 453. There can be two proximally extending extensions 453, for example forming a U-shaped connection. Each extension 453 can include an opening 455 therethrough. The extensions 453 can define a space 457 therebetween. When installed with the worm gear 412 located in the space 457, the extensions 453 can laterally surround the worm gear 412, and a pin or other feature can extend through the openings 455 and a central opening of the worm gear 412 to connect the link 450 with the worm gear 412.

[0145] The housing 459 can move linearly relative to the fixed portion 451. The fixed portion 451 can define a longitudinal axis along which the housing 459 can translate. A spring 456 can be located within the link 450. As shown, a proximal end of the spring 456 can be located within the fixed portion 451 and attached to a proximal end of the link 450. A distal end of the spring 456 can be attached to a proximal end of the housing 459. In some embodiments, the spring 456 can extend through and be attached to the housing 459. FIG. 5E FIG. 5D The link 450 is shown deployed relative to the configuration in FIG. 5C . The deployed housing 459 will stretch the spring 456. The spring 456 will exert a restoring force on the housing 459 and bias the housing proximally. The link 450 can then return to the configuration shown in FIG. 5C As the finger is rotated to close the finger 400 and then rotated back to open the finger 400, the link 450 can repeatedly extend and retract. Thus, as described further herein, for example, with reference to FIGS. 6A-6D the link 450 can deploy during rotation of the finger 400. In some embodiments, as described further herein, for example, with reference to FIGS. 7A-7D the link 450 can not deploy during rotation of the finger 400 to increase degrees of freedom.

[0146] FIGS. 6A-6D are sequential views of the prosthetic finger 400 shown in various rotational configurations. The sequential views illustrate an embodiment in which the middle segment 430 and the distal segment 440 rotate as the proximal segment 420 rotates. The rotation of the segments 420, 430, 440 can be due to the configuration and interaction of the mounting 410, the segments 420, 430, 440, and the links 450, 460.

[0147] The proximal segment 420 can rotate relative to the mounting 410 about the joint 418 (see FIGS. 4A-4B To initiate rotation of the finger 400, the actuator 404 can rotate the worm 414 and, in turn, the worm gear 412 about the first axis.

[0148] ​In some embodiments, the link 450 can rotate about the first axis as the worm gear 412 rotates. The link 450 can rotate the same or a similar amount of degrees as the worm gear 412 rotates. For example, a fifteen degree clockwise rotation of the worm gear 412 can cause the link 450 to rotate fifteen degrees clockwise, etc.

[0149] In some embodiments, rotation of the link 450 can cause the proximal segment 420 to rotate. For example, the link 450 can be attached to the proximal segment 420 such that rotation of the link 450 in the first or second rotational direction can cause corresponding rotation of the proximal segment 420 in the first or second rotational direction, respectively.

[0150] In some embodiments, rotation of the worm gear 412 can not cause the link 450 or the proximal segment 420 to rotate. For example, the link 450 can be rotatably connected to the worm gear. As such, rotation of the worm gear 412 can not cause the link 450 to rotate. FIGS. 7A-7D Further described, the middle segment 430 and the distal segment 440 can thus rotate, while the proximal segment 420 does not rotate or rotates less than a full rotation. In some embodiments, actuation of the finger segment can be provided by an actuation tendon 470 connected to the worm gear 412 and the segments 420, 430, 440, such that rotation of the worm gear 412 will cause the tendon to pull in (shorten) to cause rotation of the segments 420, 430, 440. As described herein, a return tendon 480 can rotate the finger 400 in the opposite direction, and the worm gear 412 can rotate in the opposite direction to allow the actuation tendon to let out (lengthen). Thus, in some embodiments, the worm gear 412 can rotate about the first axis, while the proximal end of the link 450 does not rotate about the first axis.

[0151] The finger 400 can include an actuation tendon 470. The tendon 470 extends from a proximal end 472 attached to the worm gear 412 to a distal end 474 attached to an attachment 478 of the middle segment 430. The tendon 470 extends distally from the worm gear 412 and around an idler 476, e.g., a pulley, which can or can not rotate, and which is connected to the proximal segment 420. As the worm gear 412 rotates in a clockwise direction as oriented, the proximal end 472 of the tendon 470 loops around the worm gear 412. The length of the tendon 470 effectively shortens, thus pulling on the attachment 478 and exerting a force on the idler 476, causing the middle and proximal segments, respectively connected to the attachment 478 and the idler 476, to rotate in the clockwise direction as oriented. FIGS. 6A to 6D (also shown in FIGS. 7A to 7D As the worm gear 412 rotates in a clockwise direction as oriented, the proximal end 472 of the tendon 470 loops around the worm gear 412. The length of the tendon 470 effectively shortens, thus pulling on the attachment 478 and exerting a force on the idler 476, causing the middle and proximal segments, respectively connected to the attachment 478 and the idler 476, to rotate in the clockwise direction as oriented.

[0152] The finger 400 can include a return tendon 480. The return tendon 480 extends from a proximal end 481 attached to a plunger 482. The plunger 482 is biased in the proximal direction by a compression spring 486 within the housing 403. The tendon 480 extends in the distal direction from the housing 403 around an idler 485, e.g., a pulley, which can or can not rotate, to a distal end 484 of the tendon 480 attached to an attachment 483 of the proximal segment 420. As the proximal segment 420 rotates in the oriented clockwise direction, the attachment 483 pulls the return tendon 480, causing the plunger 482 to move distally and compress or further compress the spring 486 due to the described actuation tendon 470. The spring 486 is thus further compressed as the finger 400 is further rotated clockwise. The spring 486 thus exerts a biasing force in the proximal direction on the plunger 482, biases the tendon 480 in the proximal direction, and exerts an opening force or counterclockwise force on the proximal segment 420 through the attachment 483. In some embodiments, the spring 486 can be a constant force spring to exert a constant return force on the segment 420 at various rotational positions.

[0153] As the worm gear 412 rotates in the oriented counterclockwise direction to effectively lengthen or loosen the actuation tendon 470, the biasing force on the return tendon 480 causes the proximal segment 420 to rotate open, or in the oriented counterclockwise direction. In addition, as described herein, the spring-loaded expandable link 450 then pulls the middle segment 430 proximally at the connection 458 to rotate the middle segment 430 counterclockwise about the joint 428. The ear 432 can then rotate counterclockwise about the joint 428 to rotate the connection 461 of the distal link 460 counterclockwise about the joint 428, thereby rotating the distal segment 440 counterclockwise as well.

[0154] The tendons 470, 480 are merely one example of how to effectuate articulation of the segments 420, 430, 440 in the prosthetic finger 400 having the expandable link 450. Some embodiments of the prosthetic finger 400 having the expandable link 450 can not include the actuation tendon 470 and / or the return tendon 480. For example, features other than tendons can be used, e.g., other links, connections, joints, segments, etc. Thus, the embodiments shown and described herein for articulation of the segments 420, 430, 440 are merely example embodiments of how the prosthetic finger 400 having the expandable link 450 can be implemented.

[0155] As the link 450 rotates, the link 450 translates or sweeps a rotational path with the rotatable connection 458 of the middle segment 430. The middle segment 430 is constrained in translation at the connection 458 by the distal end 459 of the link 450. Thus as the middle segment 430 rotates to open or close the finger 400, the middle segment 430 rotates about the connection 458 relative to the link 450. The middle segment 430 also rotates about the joint 428 relative to the proximal segment 420 (see FIGS. 4A-4B ).

[0156] As the mid-section 430 rotates, the connector 461 at the proximal end 462 of the distal link 460 moves along the groove 433. The connector 461 may include a pin that slides along the groove 433. This allows the ear 432 to rotate relative to the distal link 460. The distal link 460 thus rotates relative to the mid-section 430. As the distal link 460 rotates, the distal link 440 also rotates due to the connector 468 between the distal link 460 and the distal link 440. The distal link 440 rotates about the joint 438 relative to the mid-section 430.

[0157] like FIG. 6B and 6D As shown, mounting member 410 or a portion thereof may extend along axis 1. Proximal segment 420 may extend along axis 2. Axis axes 1 and 2 may form an angle A between them. Angle A may be an angular configuration of the proximal segment 420 relative to mounting member 410. Angle A may start from zero degrees (e.g., at...). FIG. 6A (in the middle) to ninety degrees or greater (e.g., in the middle) FIG. 6D (The angle A varies). In some embodiments, angle A can be -15, -10, -5, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, or 115 degrees, or other smaller, larger, or intermediate angles. Various values ​​of angle A can be applied to... FIGS. 6A-6D Any joint connection configuration and other configurations of any of the prosthetic fingers 400 shown.

[0158] Angle A can change with the rotation of the finger 40°, for example, with the rotation of the middle segment 43° and the distal segment 44°. As shown in the figure, from FIG. 6B relative open configuration to FIG. 6D With a relatively closed configuration, angle A can increase, and vice versa. Angle A can depend on the amount of rotation of the middle and distal segments 430, 440, and vice versa. In some embodiments, angle A may not change with the rotation of finger 400, for example, with the rotation of the middle segment 430 and distal segment 440. For example, from FIG. 6B relative open configuration to FIG. 6D In a relatively closed configuration, angle A may not change, and vice versa. In some embodiments, from FIG. 6B relative open configuration to FIG. 6D With a relatively closed configuration, angle A can be varied slightly, and vice versa, for example, by 5 degrees or less, 10 degrees or less, 15 degrees or less, or 20 degrees or less. Therefore, as in this paper, for example... FIGS. 7A-7D To elaborate further, angle A may therefore not depend on the amount of rotation of the middle section 430 and the far section 440, or vice versa.

[0159] The finger 400 can be rotated as described to have a closed configuration as shown in 6D. The proximal segment 420 can be at about ninety degrees to the axis 1 along its axis of extension 2. The middle segment 420 can be rotated to be approximately parallel to the axis 1. In some embodiments, in the closed configuration, the middle segment 420 can not be parallel to the axis 1. Also as shown, the distal segment 440 is rotated clockwise to be adjacent to the proximal segment 420. The segments 420, 430, 440 can thus be rotated to provide a smaller closed grip to the finger 400.

[0160] FIGS. 7A-7D is a sequential view of the prosthetic finger 400 performing rotations with increased degrees of freedom. The finger 400 is shown in various rotational configurations, in which the middle segment 430 and the distal segment 440 rotate independently of the rotation of the proximal segment 420 due to the interaction of the links 450, 460. Unless otherwise noted, the finger 400 can be rotated similarly as described. FIGS. 6A-6D

[0161] In some embodiments, the finger 400 can be rotated to grasp or cover an object having an irregular outer surface or contour. Due to the irregular outer surface, FIGS. 6A-6D the rotational path of the finger 400 shown can not sufficiently cover or grasp the object. Thus, the proximal segment 420 and / or the middle segment 430 can be prevented from rotating clockwise beyond a certain amount of degrees. In this case, the middle segment 430 and / or the distal segment 440 can continue to rotate to provide the desired functionality. FIGS. 7A-7D An exemplary embodiment is shown in which the finger 400 is rotated with the proximal segment 420 not rotating clockwise or not fully rotating clockwise, while the middle and distal segments 430, 440 rotate clockwise.

[0162] As the finger 400 is rotated from FIG. 7A to FIG. 7D , the proximal segment 420 can be prevented from rotating. This can be due to a force exerted on the proximal segment 420 by an external object resisting the closing direction, such as a portion of the object the finger 400 is grasping. Due to the unfolding of the link 450, the middle segment 430 and the distal segment 440 can continue to rotate. The link 450 as shown can elongate as the finger 400 is rotated. The housing 459 can extend distally away or towards the fixed portion 451 as the finger 400 is rotated clockwise or counterclockwise, respectively. As shown, the angle A between the axes 1 and 2 can not change as a result, or can change by a small amount as shown, for example, in FIG. 7D FIGS. 6A-6D

[0163] The link 450 can have, for example, FIG. 7A a first axial length when the finger is straightened; FIG. 7B a second axial length when the finger 400 has been partially rotated; FIG. 7C ​​​The third axial length when the finger rotates 400 degrees further but not completely; and FIG. 7D The fourth axial length when the finger is fully rotated 400 degrees. The first length can be shorter than each of the second, third, and fourth lengths. The second length can be shorter than each of the third and fourth lengths. The third length can be shorter than the fourth length.

[0164] The middle section 430 and the far section 440 are in accordance with FIGS. 6A-6D Rotation as described. The extended and retracted link 450 allows the middle section 430 and the distal section 440 to rotate without or partially with the proximal section 420 rotating. In some embodiments, the link 450 may not rotate. In some embodiments, the link 450 may rotate partially. In some embodiments, a rib may be used to cause rotation of the middle section 430 and the distal section 440 when the proximal section 420 does not rotate or partially rotates. The rib may be arranged according to... FIGS. 6A-6D It is attached to the worm gear 412 as described to cause rotation.

[0165] FIGS. 8A-8C Various views are of embodiments of actuator 501 that can be used with the various prosthetic fingers described herein. FIG. 8A This is a side view of actuator 501 in its extended configuration. FIG. 8B This is a side view of actuator 501 in its retracted configuration. FIG. 8C It is along FIG. 8A The diagram shows a cross-sectional view of actuator 501 taken along line 8C-8C. Actuator 501 can be used in any prosthetic finger disclosed herein, for example... FIGS. 1A-3H The prosthetic finger. Unless otherwise stated, actuator 501 may have the same or similar features and / or functions as actuators 301 and 404, and vice versa.

[0166] like FIG. 8A As shown, actuator 501 includes a proximal end 513 and extends to a distal end 517. The proximal end 513 can be attached to a hand, palm, etc. The distal end 517 can be attached to the proximal end of a proximal segment of a prosthetic finger.

[0167] Advantageously, the actuator 501 is compact. The actuator 501 is small enough to be at least partially fitted within the prosthetic finger. The size of the actuator 501 can be configured to fit the proximal end of a prosthetic finger of a typical-sized prosthetic hand. The prosthetic hand may include multiple actuators 501, for example, one actuator 501 in each of its prosthetic fingers. In some embodiments, in a closed or retracted configuration, the total volume of the actuator 501 does not exceed 11,550 mm². 2(mm). In some embodiments, in the closed or retracted configuration, the maximum length of the actuator 501 is no more than 75 mm and the maximum width is no more than 14 mm. In the closed or retracted configuration, the total volume of the actuator 501 can be no more than 11,550 mm 2 , no more than 5,000 mm 2 , no more than 7,500 mm 2 , no more than 10,000 mm 2 , no more than 12,500 mm 2 , or no more than 15,000 mm 2 . In the closed or retracted configuration, the maximum length of the actuator 501 can be no more than 75 mm (millimeters), no more than 25 mm, no more than 50 mm, no more than 100 mm, or no more than 125 mm, and / or the maximum width is no more than 14 mm, no more than 8 mm, no more than 10 mm, no more than 12 mm, no more than 16 mm, no more than 18 mm, or no more than 20 mm. The aspect ratio of the actuator 501 can be no less than 1.5, no less than 2, no less than 2.5, no less than 3, no less than 3.5, no less than 4, no less than 4.5, or no less than 5, the aspect ratio being defined as the ratio of the maximum length in the retracted state to the maximum width in the retracted state.

[0168] In the open or extended configuration, in some embodiments, the total volume of the actuator 501 can be no more than 14,164 mm 2 . The actuator 501 can have a maximum length of 92 mm and / or a maximum width of 14 mm. In the open or extended configuration, the total volume of the actuator 501 can be no more than 10,000 mm 2 , no more than 12,000 mm 2 , no more than 13,000 mm 2 , no more than 13,500 mm 2 , no more than 14,000 mm 2 , no more than 14,500 mm 2 , no more than 15,000 mm2, or no more than 16,000 mm 2 . In the open extended configuration, the maximum length of the actuator 501 can be no more than 50 mm, no more than 60 mm, no more than 70 mm, no more than 80 mm, no more than 90 mm, no more than 95 mm, no more than 100 mm, or no more than 110 mm. In the open or extended configuration, the maximum width of the actuator 501 can be no more than 5 mm, no more than 8 mm, no more than 10 mm, no more than 12 mm, no more than 14 mm, no more than 16 mm, no more than 18 mm, no more than 20 mm, or no more than 25 mm.

[0169] The actuator 501 is a linear, telescoping linear actuator. The actuator 501 generates or causes linear motion. As shown, the actuator 501 includes a motor 505 and a gearbox 512. The motor 505 is mechanically coupled to the gearbox 512. The motor 505 is powered by a battery that can be in the hand or elsewhere. The actuator 501 includes a shaft 507 that extends axially and distally from the gearbox 512 and / or the motor 505. The actuator 501 can include a lead screw 514 coupled to the motor 505, e.g., coupled to the shaft 507. The lead screw 514 can have external threads 519 that mate with threads of other components in the actuator 501. The lead screw 514 can be or include a worm.

[0170] The actuator 501 includes a support 510. The support 510, such as a motor mount or other structure, can carry or otherwise support the actuator 501 and / or the motor 505. The support 510 can be configured to attach the actuator 501 to a hand. For example, the support 510 can be configured to receive a pin or other suitable feature at its proximal end to secure the support 510 to, e.g., rotatably attach to, a mount (e.g., a mount on a hand, palm, etc.). The support 510 can include a connector portion 522, e.g., FIG. 8B The opening shown can receive a pin or other suitable feature in the proximal end 513. As described herein, the actuator 501 can rotate about an axis defined by the connector portion 522 as the actuator 501 linearly extends and retracts.

[0171] The actuator 501 includes a housing 511. The housing 511 axially telescopes. The housing 511 defines a cavity 515 therein. The cavity 515 can be a cylindrical opening inside the housing 511 or extending axially through the housing 511. The cavity 515 can have a maximum length and a maximum diameter. The ratio of the maximum length to the maximum diameter can be no less than 1.5, no less than 2, no less than 2.5, no less than 3, no less than 3.5, no less than 4, no less than 4.5, or no less than 5. The ratio of the maximum length to the maximum diameter can be 3-6. The cavity 515 can be configured to receive therein the gearbox 512, the shaft 507, the lead screw 514, and / or at least a portion of the motor 505. The housing 511 can have internal threads 516. For example, as shown, the internal threads 516 can be positioned along the cavity 515 of the housing 511. The proximal end of the housing 511 can be open to the cavity 515. The distal end 517 of the housing 511 can correspond to the distal end 517 of the actuator 501. The distal end of the housing 511 can connect with a proximal segment of a prosthetic finger at a joint. For example, as shown, the distal end of the housing 511 can include an opening 523 configured to engage a proximal portion of a prosthetic finger. As described herein, the actuator 501 can rotate about an axis defined by the opening 523 as the actuator 501 linearly telescopes. FIG. 8A

[0172] ​The actuator 501 can include an axially fixed portion and an axially movable portion. The fixed and movable portions can be fixed and movable, respectively, with respect to a longitudinal axis of the actuator 501, such as the axis L shown in FIG. 8C The axially movable portion of the actuator 501 can slidably engage an outer surface of the fixed portion. The axially movable portion can include a housing 511. The axially fixed portion can include a motor 505, a gearbox 512, a support 510, a lead screw 514, and a shaft 507.

[0173] The actuator 501 can output linear motion to cause rotation of a prosthetic finger. For example, the housing 511 can translate axially to cause rotation of a proximal segment of a prosthetic finger. The motor 505 or other portion of the actuator 501 can use or provide rotational, linear, cyclical, and / or other types of motion.

[0174] The motor 505 can rotate the lead screw 514 about a longitudinal axis L (as shown in FIG. 8C The shaft 507 can be configured to be rotated by the motor 505 and to rotate the lead screw 514 about the longitudinal axis L in a first rotational direction and a second rotational direction opposite the first rotational direction. The internal threads 516 of the housing 511 can be configured to at least partially engage the external threads 519 of the lead screw 514 such that rotation of the lead screw 514 causes the housing 511 to translate axially along the longitudinal axis L relative to the lead screw 514 and / or the support 510 while the lead screw 514 remains axially fixed. For example, the external threads 519 of the lead screw 514 can be mechanically coupled to the internal threads 516 of the housing 511. Rotation of the lead screw 514 in the first rotational direction causes the housing 511 to translate distally relative to the lead screw 514 and / or the support 510, and rotation of the lead screw 514 in the second rotational direction causes the housing 511 to translate proximally relative to the lead screw 514 and / or the support 510.

[0175] The actuator 501 can be used in a prosthetic finger having a base configured to be attached to a hand, a proximal segment, a middle segment, and a distal segment, an expandable link, and a wheel, such as a worm gear or other rotatable member. The wheel can be placed in mechanical communication with the actuator 501. The actuator 501 can be configured to cause the wheel to rotate. As described herein, for example, with reference to FIGS. 6A-7D The prosthetic finger can include a tendon extending distally from the wheel, a pulley rotatably connected to the proximal segment, and a tendon attachment coupled to the middle segment. When the actuator 501 is used in the prosthetic finger, translation of the housing 511 in the distal direction along the longitudinal axis L of the actuator 501 relative to the lead screw 514 can cause the proximal segment of the prosthetic finger to rotate about a joint, which can cause the middle segment and the distal segment to rotate. As described, rotation of the wheel in the first rotational direction caused by the actuator 501 can pull the tendon proximally and cause the distal segment of the prosthetic finger to rotate relative to the middle segment.

[0176] The actuator 501 can be used in various other prosthetic fingers. The examples provided herein are merely some embodiments. The compactness of the actuator 501 allows it to be used in each of the prosthetic fingers in a prosthetic hand, e.g., one, two, three, four, or five actuators 501 can be used in each of the corresponding prosthetic fingers. The actuator 501 can be housed entirely or partially within a prosthetic finger. The actuator 501 can be housed entirely or partially within a hand.

[0177] Further, in some embodiments, the actuator 501 can be assembled in a flipped orientation as described herein. For example, the actuator 501 can be flipped in an orientation from proximal to distal such that the movable portion and the fixed portion are reversed. The housing 511 can be axially fixed while the motor 505 and other components can be axially moved. The housing 511 can be attached to a prosthetic hand and the motor 505 (e.g., motor mount 510) can be attached to a prosthetic finger, e.g., a proximal segment. Thus, the general principles of the actuator 501 described herein can be used in various environments within the scope of the present disclosure.

[0178] FIGS. 9A-9D are various views of another embodiment of a linear actuator 601 that can be used with various prosthetic fingers described herein. FIG. 9A is a side view of the actuator 601 in an extended mechanism configuration. FIG. 9B is a side view of the actuator 601 in a retracted mechanism configuration. FIG. 9C and 9D is a cross-sectional view of the actuator 601 taken along line 9C-9C shown in FIG. 9. The actuator 601 can be used in any of the prosthetic fingers disclosed herein, e.g., a prosthetic finger as shown in FIGS. 1A-3H Unless otherwise noted, the actuator 601 can have the same or similar features and / or functionality as the actuators 301, 404, 501 and vice versa.

[0179] As shown in FIG. 9A The actuator 601 includes a proximal end 613 and extends to a distal end 617. The proximal end 613 can be attached to a hand, palm, etc. The distal end 617 can be attached to a proximal end of a proximal segment of a prosthetic finger.

[0180] Advantageously, the actuator 601 is compact. The actuator 601 is small enough to fit at least partially within a prosthetic finger. The actuator 601 can be sized to fit a proximal end of a prosthetic finger of a typical sized prosthetic hand. A prosthetic hand can include multiple actuators 601, e.g., one in each of its prosthetic fingers. In a closed or retracted configuration, the total volume of the actuator 601 does not exceed 6,222 mm 2In the closed or retracted configuration, the actuator 601 can have a maximum length of 55 mm and / or a maximum width of 12 mm. In the closed or retracted configuration, the total volume of the actuator 601 can be no more than 3,000 mm 2 , no more than 4,000 mm 2 , no more than 5,000 mm 2 , no more than 5,500 mm 2 , no more than 5,750 mm 2 , no more than 6,000 mm 2 , no more than 6,500 mm 2 , no more than 6,750 mm 2 , or no more than 7,000 mm 2 . The aspect ratio of the actuator 601, defined as the ratio of the maximum length in the retracted state to the maximum width in the retracted state, can be no less than 1.5, no less than 2, no less than 2.5, no less than 3, no less than 3.5, no less than 4, no less than 4.5, or no less than 5.

[0181] In the open or extended configuration, in some embodiments, the total volume of the actuator 601 can be no more than 7,918 mm 2 . In the open or extended configuration, in some embodiments, the actuator 601 can have a maximum length of 70 mm and / or a maximum width of 12 mm. In the open or extended configuration, the total volume of the actuator 601 can be no more than 5,000 mm 2 , no more than 6,000 mm 2 , no more than 7,000 mm 2 , no more than 7,500 mm 2 , no more than 7,750 mm 2 , no more than 8,000 mm 2 , no more than 8,250 mm 2 , no more than 8,500 mm 2 , no more than 8,750 mm 2 , no more than 9,000 mm 2 . In the open or extended configuration, the maximum length of the actuator 601 can be no more than 50 mm, no more than 60 mm, no more than 65 mm, no more than 70 mm, no more than 75 mm, no more than 80 mm, no more than 85 mm, or no more than 90 mm. In the open or extended configuration, the maximum width of the actuator 601 can be no more than 6 mm, no more than 8 mm, no more than 10 mm, no more than 11 mm, no more than 12 mm, no more than 13 mm, no more than 14 mm, no more than 16 mm, or no more than 18 mm.

[0182] The actuator 601 is a linear, telescoping linear actuator. The actuator 601 generates or causes linear motion. As shown, the actuator 601 includes a motor 605 and a gearbox 612. The motor 605 is mechanically coupled to the gearbox 612. The gearbox 612 can be directly mechanically coupled to the motor 605. For example, the gearbox 612 is shown as mounted on the motor 605. The gearbox 612 can be positioned away from the motor 605. For example, the gearbox 612 can be used in a gear train away from the motor 605. The gearbox 612 can thus be located elsewhere within the hand, and / or have an auxiliary gearbox between the motor 605 and the gearbox 612. The motor 605 is powered by a battery that can be located within the hand or elsewhere. The actuator 601 includes a shaft 607 that extends axially distally from the gearbox 612 and / or the motor 605. The actuator 601 can include a lead screw 614 coupled to the motor 605 (e.g., connected to the shaft 607). The lead screw 614 can be or include a worm. The lead screw 614 can have external threads 619 that mate with threads of other components in the actuator 601.

[0183] The actuator 601 can include a thrust bearing 621. FIG. 9C The actuator 601 with the thrust bearing 621 is shown taken along line 9C-9C, FIG. 9D The actuator 601 with the thrust bearing 621 is shown taken along a plane that is FIG. 9C The actuator 601 with the thrust bearing 621 is shown taken along a plane that is The thrust bearing 621 can extend through a window 626 of a passage 625 of the housing 611. The thrust bearing 621 can be configured to axially engage the lead screw 614, for example by engaging a distal end and / or a proximal end of the lead screw 614. The thrust bearing 621 can be connected to, for example threaded to, a distal end of the gearbox 612. The thrust bearing 621 can be a housing positioned near the distal end of the gearbox 612. The thrust bearing 621 can have threads that mate with threads of other components in the actuator 601, for example with the distal end of the gearbox 612. The lead screw 614 can be axially enclosed on either side by the thrust bearing 621. For example, the lead screw 614 can be axially constrained by the thrust bearing 621. The thrust bearing 621 can be configured to contact the worm gear. The thrust bearing 621 can be made of a different material than the worm gear, providing a bearing surface when the thrust bearing 621 and the worm gear are in dynamic contact. The lead screw 614 can be free to axially float on the motor shaft. The lead screw 614 can be constrained during radial motion by the lead screw hole and a corresponding "D" shaped profile on the motor shaft.

[0184] The thrust bearing 621 can be configured to convert rotational motion of the shaft 607 into linear or axial forces. For example, rotation of the shaft 607 can cause the thrust bearing 621 (and the leadscrew 614 coupled to the thrust bearing 621) to move axially relative to the housing 611. As the actuator 601 is moved, the axial force on the leadscrew 614 resulting from the linear actuation can be transferred into the thrust bearing 621. As shown, the thrust bearing 621 has an internal thread at its proximal end that is mounted to the distal end of the gearbox 612. The thrust bearing 621 supports the leadscrew 614 in an axial direction. The line of action of the force transfer as the actuator 601 is actuated can be as follows: from the rotation of the shaft 607 of the gearbox; from the shaft 607 to the leadscrew 614; from the external thread of the leadscrew 614 to the internal thread 616 of the housing 611 as the leadscrew 614 climbs or otherwise moves along the internal thread 616 of the housing 611; from the leadscrew 614 to the axial force of the thrust bearing 621, which can be in either the proximal or distal direction of the thrust bearing 621, depending on the direction of movement of the housing 611; and from the thrust bearing 621 to the threaded connection with the distal end of the gearbox 612.

[0185] The actuator 601 includes a support 610. The support 610, such as a motor mount or other structure, can carry or otherwise support the actuator 601 and / or the motor 605. The support 610 can be configured to attach the actuator 601 to a hand. For example, the support 610 can include a connector portion 622, such as an opening or a protrusion (e.g., a post), that mates with a hand. For example, the support 610 can be configured to receive a pin or other suitable feature on its proximal end to secure the support 610 to, for example, rotatably attach to, a mount (e.g., a mount on a hand, a palm, etc.). As shown, the support 610 can include a connector portion 622 on the proximal end 613 that can be received in a portion of a mount, such as a groove or other opening, on a hand, a palm, etc., to secure the support 610 to, for example, rotatably attach to, the mount. As described herein, the actuator 601 can rotate about an axis defined by the connector portion 622 as the actuator 601 linearly extends. FIG. 9C

[0186] ​The actuator 601 includes a housing 611. The housing 611 is axially telescoping. The housing 611 defines a cavity 615 therein. The cavity 615 can be a cylindrical opening inside the housing 611 or extending axially through the housing 611. The cavity 615 can have a maximum length and a maximum diameter. The ratio of the maximum length to the maximum diameter can be no less than 1.5, no less than 2, no less than 2.5, no less than 3, no less than 3.5, no less than 4, no less than 4.5, or no less than 5. The ratio of the maximum length to the maximum diameter can be 3-6. The cavity 615 can be configured to receive therein the gearbox 612, the shaft 607, the lead screw 614, and / or at least a portion of the motor 605. The housing 611 can have an internal thread 616. For example, as shown, the internal thread 616 can be positioned along the cavity 615 of the housing 611. A proximal end of the housing 611 can be open to the cavity 615. A distal end of the housing 611 can correspond to a distal end 617 of the actuator 601. The distal end of the housing 611 can be connected at a joint to a proximal segment of a prosthetic finger. For example, as shown, the distal end of the housing 611 can include an opening 623 configured to engage a proximal portion of a prosthetic finger. As described herein, the actuator 601 can rotate about an axis defined by the opening 623 when the actuator 601 linearly telescopes. FIG. 9A

[0187] The housing 611 can include a channel 625 along an outer surface of the housing 611. The channel 625 can extend along a portion of the length of the housing 611. The channel 625 can be rectangular, elliptical, or any other suitable shape. The channel 625 can be configured to slidably engage the thrust bearing 621 and / or a portion of the lead screw 614. The channel 625 can provide visibility (e.g., a window corresponding to the component) to components within the housing 611, such as the thrust bearing 621 and / or the lead screw 614.

[0188] The actuator 601 can include an axially fixed portion and an axially movable portion. The fixed portion and the movable portion can be fixed and movable, respectively, relative to a longitudinal axis of the actuator 601, such as the axis L shown in FIG. 9C The axially movable portion of the actuator 601 can slidably engage an outer surface of the fixed portion. The axially movable portion can include the housing 611. The axially fixed portion can include the motor 605, the gearbox 612, the support 610, the lead screw 614, and the shaft 607.

[0189] The actuator 601 can output linear motion to cause rotation of a prosthetic finger. For example, the housing 611 can axially translate to cause rotation of a proximal segment of a prosthetic finger. The motor 605 or other portion of the actuator 601 can use or provide rotational, linear, cyclical, and / or other types of motion.

[0190] The motor 605 can cause the lead screw 614 to rotate about the longitudinal axis L (as shown in FIG. 9C ​(As shown) Rotation. Shaft 607 can be configured to be rotated by motor 605 and configured to rotate screw 614 about longitudinal axis L in a first rotation direction and a second rotation direction opposite to the first rotation direction. The internal thread 616 of housing 611 can be configured to engage at least partially with the external thread 619 of screw 614, such that rotation of screw 614 causes housing 611 to translate axially relative to screw 614 and / or support 610 along longitudinal axis L, while screw 614 remains axially fixed. For example, external thread 619 of screw 614 can be mechanically connected to internal thread 616 of housing 611. Rotation of screw 614 in the first rotation direction causes housing 611 to translate distally relative to screw 614 and / or support 610, and rotation of screw 614 in the second rotation direction causes housing 611 to translate proximally relative to screw 614 and / or support 610.

[0191] Actuator 601 can be used in a prosthetic finger having a base configured to attach to a hand, proximal, mid- and distal segments, an extendable link, and a wheel, such as a worm gear or other rotatable component. The wheel can be positioned to be mechanically connected to actuator 601. Actuator 601 can be configured to rotate the wheel. See, for example, herein... FIGS. 6A-7D The prosthetic finger may include a rib extending distally from the wheel, a pulley rotatably connected to the proximal segment, and a rib attachment connected to the mid-segment. When the actuator 601 is used with the prosthetic finger, translation of the housing 611 along the longitudinal axis L of the actuator 601 relative to the lead screw 614 in the distal direction can cause rotation of the proximal segment of the prosthetic finger about the joint, which may result in rotation of the mid-segment and distal segment. As described, rotation of the wheel in the first rotational direction caused by the actuator 601 can pull the rib proximally and cause rotation of the distal segment of the prosthetic finger relative to the mid-segment.

[0192] Actuator 601 can be used in a variety of other prosthetic fingers. The examples provided herein are only some embodiments. The compactness of actuator 601 allows it to be used in each prosthetic finger of the prosthetic hand; for example, one, two, three, four, or five actuators 601 can be used in each of the corresponding prosthetic fingers. Actuator 501 can be fully or partially housed within the prosthetic finger. Actuator 601 can be fully or partially housed within the hand.

[0193] Further, in some embodiments, the actuator 601 can be assembled in a flipped orientation of the directions as described herein. For example, the actuator 601 can be flipped in a direction from proximal to distal such that the movable portion and the fixed portion are reversed. The housing 611 can be axially fixed while the motor 605 and other components can be axially movable. The housing 611 can be attached to a prosthetic hand and the motor 605, e.g., motor mount 610, can be attached to a prosthetic finger, e.g., a proximal segment. Thus, the general principles of the actuator 601 described herein can be used in a variety of environments within the scope of the present disclosure.

[0194] FIGS. 10A-10C is various views of an embodiment of a prosthetic finger 300A. The finger 300A can be used with the system 100 or the hand 200. Unless otherwise noted, the finger 300A can have the same or similar features and / or functionality as the finger 300, and vice versa. FIG. 10A is a perspective view of the finger 300A, FIG. 10B is an exploded view of the finger 300A, and FIG. 10C is a side cross-sectional view of the finger 300A taken along line 10C-10C shown in FIG. 10.

[0195] As described herein, e.g., with reference to Figures 3A-3H The finger 300A includes segments 320, 330, 340 and links 360, 370. The finger 300A also includes an actuator 310A. The actuator 310A includes a motor 305A and a shaft 307A, which can have the same or similar features and / or functionality as the motor 305 and the shaft 307, respectively. The motor 305A rotates the shaft 307A about a longitudinal axis of the motor 305A.

[0196] The actuator 301A includes a support 310. The motor 305A is supported by the support 310. The support 310 extends longitudinally and defines a cavity 310A therein.

[0197] The cavity and / or sidewall of the support 310 can carry the motor 305A. The shaft 307A extends through an opening defined by a first protrusion 310B and a second protrusion 310C of the support 310 that extend upwardly therefrom to define a space therebetween. As described herein, a lead screw 314 having external threads thereon is attached to the shaft 307A between the first protrusion 310B and the second protrusion 310C such that rotation of the shaft 307A will cause the lead screw 314 to rotate in the space defined by the protrusions 310B, 310C. A nut or end cap can be attached to the distal end of the shaft distally of the second protrusion 310C to axially secure the motor 305A with the support 310. The support 310 extends from a proximal end having a transverse opening 302 therethrough to a distal end having protrusions 310B, 310C extending upwardly therefrom. The cavity 310A extends within the support 310 from the proximal end to the distal end.

[0198] The actuator 310A includes a rack 380. The rack 380 can be a worm rack. The rack 380 extends from a proximal end 382 to a distal end 384. The proximal end 382 includes an elongated portion having threads 386. The threads 386 can be partially threaded as shown. The threads 386 extend transversely and are positioned along the length of the rack 380. The distal end 384 includes an opening 389 configured to connect with the connector 358 at the proximal end 362 of the proximal link 360. The rack 380 can be part of the internal threaded portion of the housing 311 described herein. The rack 380 can include a joint 388 that is rotatably attached to the proximal segment 320 and the proximal end 384 can rotate about the joint as the rack pushes or pulls at the joint 388 during axial movement. The joint 388 can be an opening having a pin extending therethrough that rotationally connects the distal end of the threaded portion of the rack 380 and the proximal end of the distal end 384. The rack 380 can cause the proximal segment 320 to rotate or pivot about the joint 318 by pushing or pulling at the joint 388.

[0199] The rack 380 can be part of the housing 311 as described herein. The rack 380 can be a lower proximal portion of the housing 311. The rack 380 can linearly slide within the cavity 310A of the support 310. The rack 380 can axially translate due to the engagement of the threads 386 with the threads of the lead screw 314. As the lead screw 314 rotates, the threads of the lead screw engage the threads 386 of the rack 380 to cause the rack 380 to axially move. The rack 380 can translate distally in response to rotation of the lead screw in a first rotational direction and the rack 380 can translate proximally in response to rotation of the lead screw in a second rotational direction opposite the first rotational direction.

[0200] The axial movement of the rack 380 will cause the proximal end 362 of the proximal link 360 to correspondingly axially move. As described herein, for example,Figures 3F-3H As described, axial translation of the proximal link 360 will cause the finger 300A to rotate closed or open depending on the direction of axial movement of the link 360. As the rack 380 pushes and pulls at the joint 388, the proximal segment 320 can rotate about the joint 318 to cause the distal end 384 to push or pull at the connector 358 through the pin passing through the opening 389.

[0201] The finger 300A can include a housing or cover over the actuator 301 A and / or other portions of the finger 300A. In some embodiments, the actuator 301 A and / or other features of the finger 300A can be located within a prosthetic hand, such as in the palm region. In some embodiments, the actuator 301 can be slightly rotated about a transverse axis to accommodate rotation of the finger 300A, such as at the opening 302 of the support 310, which can be located within a hand or palm.

[0202] The finger 300A having a linearly translatable rack 380 can improve performance and prolong the life of the finger 300A, such as by reducing the contact area and thus the friction between the threads of the lead screw 314 and the rack 380.

[0203] Figures 11A-11E are various views of an embodiment of an actuator 700 having three gear stages, which can be used in any prosthetic finger described herein. As shown in Figure 11A and 11C , the actuator 700 includes an output shaft 705, a multi-ratio gearbox 710, and a motor 760. Figure 11B is an exploded view of the actuator of Figure 11A . In this embodiment, the actuator 700 includes a first gear stage 715a, a second gear stage 715b, and a third gear stage 715c. Each of the three gear stages includes three planetary gears 717 and one sun gear 716. Between these gear stages are carriers 740a, 740b. The actuator 700 also includes a drive end cover 720, shift rings 725 for the planetary gears 717, lock tabs 730, bearings 745, mounts 755 for the motor 760, and a ring gear 750 for the first gear stage 715a. In this embodiment, the shift ring 725 mechanism is configured to engage with two gear stages. When the second gear stage 715b and the third gear stage 715c are not engaged ( Figure 11D ), the planetary gears 717 and sun gears 716 of the second stage 715b and the third stage 715c rotate with the shift ring 725 such that a portion of the outer teeth of the planetary gears 717 do not ride along or move relative to the inner teeth of the ring gear 725. When the second gear stage 715b and the third gear stage 715c are engaged ( Figure 11E), the ring gear 725 is rotationally fixed, and the planet gears 717 walk along the outer teeth of the sun gear 716 and the inner teeth of the ring gear 725. Some or all of the components, except for the motor 760, can be covered by the housing 755. The shift ring 725 can be actuated by a variety of suitable mechanisms, such as a separate linear actuator, a separate linear motor, a shape memory alloy, a bistable lever (see, e.g., Figure 13 ), other suitable mechanisms, or combinations thereof.

[0204] As further described herein, e.g., with reference to Figures 28A-31C , the multi-speed ratio gearbox 710 can employ a method of synchronizing the relative speeds of the first gear stage 715a, the second gear stage 715b, and the third gear stage 715c before engagement. This system is referred to as a synchronizer. Synchronizers can significantly reduce wear and noise during shifting, while maintaining a percentage of output torque even while shifting. There are several methods of implementing synchronization of gear elements. One method of synchronizing gear elements is to have a spring-loaded friction element contact and transmit torque before gear meshing. Another method is to have mechanical geometry (e.g., convex / concave tapered elements) that rub in contact before mechanical meshing. A third method is to utilize a shear-thickening fluid that thickens in response to an increase in shear, which can occur when out-of-sync rotating elements are brought close together. Alternatively, thickening can also be achieved by heating or applying a magnetic / electric field. As depicted in Figure 11B , embodiments of the gearbox 700 can employ the synchronizer features described herein.

[0205] Figures 11D-11E Actuator 700 is depicted in two different modes: high speed gear and low speed gear, respectively. Figure 11D Actuator 700 is shown in high speed gear with the first gear stage 715a engaged. When the actuator 700 is in high speed gear, the fewest number of gear stages are engaged. The shift ring 725 engages and rotates with the second gear stage 715b and the third gear stage 715c. The shift ring 725 is in mechanical communication with the output carrier, which is the proximal portion of the output shaft 705. The shift ring 725 is in mechanical communication with the output carrier, which is the proximal end portion of the output shaft 705. In this state, the shift ring 725 is free to rotate. The output of the motor 760 enters the second gear stage 715b through the first gear stage 715a. The output of the second gear stage 715b rotates the third gear stage 715c, and thus directly rotates the output shaft 705. This high speed gear state allows the prosthetic finger to move quickly with low torque, such that the finger moves more quickly and exerts lower gripping force.

[0206] Figure 11EThe actuator 700 is shown in a low speed gear with the first gear stage 715a, second gear stage 715b, and third gear stage 715c engaged. When the actuator 700 is in a low speed gear, the maximum number of gear stages can be engaged. The first gear stage 715a, second gear stage 715b, and third gear stage 715c can rotate. The shift ring 725 is not mechanically connected to the output carrier. Instead, the proximal tooth wall portion of the shift ring 725 can be mechanically connected to the distal recess of the ring gear 750. In this state, the shift ring 725 is rotationally fixed by the interaction with the ring gear 750 and therefore does not rotate. The output of the motor 760 rotates the first gear stage 715a, second gear stage 715b, and third gear stage 715c, which rotates the output shaft 705. This low speed gear state allows the actuator 700 to output more torque at a slower speed, such that the finger moves slower but can exert more force.

[0207] Figure 12 A partial cutaway view of an embodiment of an actuator 701 with three gear stages is depicted, which can be used in any prosthetic finger described herein. In this embodiment, the actuator 701 includes a shift ring 765, which is configured to engage with one gear stage. When the actuator 701 is in a high speed gear, the first gear stage 715a and second gear stage 715b are engaged. The shift ring 765 is engaged with and rotates with the third gear stage 715c. The shift ring 765 is mechanically connected to the output carrier. In this state, the shift ring 765 is free to rotate with the third gear stage 715c. The output of the motor 760 passes through the first gear stage 715a and second gear stage 715b. The output of the first gear stage 715a and second gear stage 715b rotates the third gear stage 715c. The third gear stage 715c subsequently directly rotates the output shaft 705. When the actuator 701 is in a low speed gear, the actuator 701 functions similarly to the actuator 700 described in the preceding paragraph with all three gear stages 715a, 715b, 715c engaged.

[0208] Figure 13 A partial cutaway view of an embodiment of an actuator 700 is shown, which is operably connected to a force feedback mechanism including a spring loaded worm 785, a worm gear 789, and a bistable spring lever 775. As the torque on the worm gear 789 increases, the worm 785 moves laterally on the worm gear 789. The bistable lever 775 does not store energy until it reaches a certain threshold. When the torque reaches this threshold, the displacement of the worm 785 drives the bistable lever 775 to switch position, thereby changing the speed ratio. The lever 775 can be connected to the worm 785 by a structural member 780, which is configured to transfer force to cause movement. In some embodiments, a separate linear actuator or other mechanism can be used to shift, such as a linear motor or shape memory alloy.

[0209] Figure 14 A side view of the actuator 700 and detent 787 on the worm 785 is shown. To minimize torque transmission interruption to the transmission 710 output, the gear ratio occurs as quickly as possible. The shift can be fully mechanical or fully electronic, or can be partially mechanical and partially electronic. In some embodiments, the gear ratio occurs fully mechanically, where the increase in torque is sensed by a mechanical system and the energy for the shift comes from mechanical action of the transmission 710. For example, a bistable switch can be created using a spring and detent. The spring and detent can effectively store potential energy from an external force and release the stored energy to shift the gear ratio as soon as the force threshold is exceeded. Figure 14 A shift method is shown whereby an increase in force on the finger drives an increase in torque on the worm 785. As the torque increases, the worm 785 climbs to a higher worm gear 789. The bistable lever 775, including a spring 790 and detent 787, flexes and stores energy until the detent 787 threshold is overcome. When the detent 787 threshold is overcome, the displacement of the worm 785 drives the bistable lever 775 to snap between positions, thereby changing the gear ratio.

[0210] In another embodiment of the actuator 800, as shown in Figure 15 the gear ratio can be supported by electronics. Figure 15 A side view of the actuator 800 with a torque sensor 895 on the worm gear 789 is shown. The torque sensor 789 can sense a gear ratio change that is occurring or about to occur by measuring motor torque, worm displacement, output torque, or force on the finger. The torque sensor 789 is configured to communicate with the motor or a processor that controls the shift. The torque sensor 789 can send measurement data to the motor or processor continuously or when the torque exceeds a certain threshold. The sensor 789 can be used in embodiments that do not have a worm and worm gear.

[0211] Figures 16A-21C Schematic diagrams of different embodiments of single or multi-gear transmissions are depicted. The various transmissions described herein can be modified to incorporate any of the functionality shown in Figures 16A-21C . Figure 16A is a schematic diagram of a switchable one-gear transmission 900A that can switch between zero-gear engagement and one-gear engagement. The switchable one-gear transmission 900A includes a gear stage 901A, a single-gear switch 905, a ring gear engagement 910, and a planetary gear engagement 915. As shown in Figure 16B when the transmission is in high gear, the gear stage 901A is not engaged and the ring gear is free to rotate. Thus, the output 920 from the motor passes through the gear stage 901A and rotates the output shaft directly. As shown in Figure 16CAs shown, when the gearbox is in the low speed gear, the gear stage 901A is engaged and the ring gear is blocked from rotation. Thus, the output 921 from the motor rotates the gear stage 901A, which rotates the output shaft of the actuator at a relatively high torque and a slow speed.

[0212] Figure 17A is a schematic diagram of a switchable two-stage gearbox 900B that can switch between one gear stage engaged and two gear stages engaged. The switchable two-stage gearbox 900B includes a first gear stage 901B, a second gear stage 902B, a single stage switch 905, a ring gear engagement 910, and a planetary gear engagement 915. As shown, Figure 17B As shown, when the gearbox is in the high speed gear, the first gear stage 901B and the ring gear are engaged, but the second gear stage 902B is not engaged. Thus, the output 921 from the motor rotates the first gear stage 901A, which directly rotates the output shaft. When the gearbox is in the low speed gear, the first gear stage 901B and the second gear stage 902B are both engaged and the ring gear is disengaged. The output 922 from the motor rotates the first gear stage 901B and the second gear stage 902B. The first gear stage 901B and the second gear stage 902B then rotate the output shaft of the actuator at a relatively high torque and a slow speed.

[0213] Figure 18A is a schematic diagram of a switchable three-stage gearbox 900C that can switch between one gear stage engaged and three gear stages engaged. The switchable three-stage gearbox 900C includes a first gear stage 901C, a second gear stage 902C, a third gear stage 903C, a two stage switch 905, a ring gear engagement 910, and a planetary gear engagement 915. As shown, Figure 18B As shown, when the gearbox is in the high speed gear with a relatively high rotational speed and a low torque, the first gear stage 901C is engaged, but the second gear stage 902C and the third gear stage 903C are not engaged. The output 921 from the motor rotates the first gear stage 901C, which directly rotates the output shaft. When the gearbox is in the low speed gear with a relatively low rotational speed and a high torque, the first gear stage 901C, the second gear stage 902C, and the third gear stage 903C are engaged. The output 923 from the motor rotates the first gear stage 901C, the second gear stage 902C, and the third gear stage 903C, which then rotate the output shaft of the actuator.

[0214] As shown, Figures 16A-18C there can be only two selectable outcomes: a high speed gear and a low speed gear. In other embodiments, as shown, Figure 19A there can be a high speed gear, two medium speed gears, and a low speed gear. Figure 19AA switchable two-gear transmission 900D is shown that includes a first gear stage 901D, a second gear stage 902D, a first primary switch 905A, a second primary switch 905B, a first ring gear engagement 910A, a second ring gear engagement 910B, a first planetary gear engagement 915A, and a second planetary gear engagement 915B. The transmission 900D can switch between zero, first, second, or first and second gear stage engagements. As shown, Figure 19B when the transmission is in the highest gear, the first ring gear 910A and the second ring gear 910B are disengaged. The output 920 from the motor passes through the first gear stage 901D and the second gear stage 902D and directly rotates the output shaft. As shown, Figure 19C when the first primary switch 905A is flipped, the first gear stage 901D is engaged and the output 921A from the motor rotates the first gear stage 901D, which rotates the output shaft of the actuator. Alternatively, as shown, Figure 19D when the second primary switch 905B is flipped, the second gear stage 902D is engaged and the output 921B from the motor rotates the second gear stage 902D, which rotates the output shaft. As shown, Figure 19E when the transmission is in the lowest gear, the first gear stage 901D and the second gear stage 902D are engaged. Thus, the output 922 from the motor rotates the first gear stage 901D and the second gear stage 902D, which rotates the output shaft of the actuator at the highest torque and slowest speed.

[0215] Figure 20A is a schematic of another embodiment of a switchable three-gear transmission 900E that can switch between two gear stage engagements and three gear stage engagements. The switchable three-gear transmission 900E includes a first gear stage 901E, a second gear stage 902E, a third gear stage 903E, a primary switch 905, a ring gear engagement 910, and a planetary gear engagement 915. As shown, Figure 20B when the transmission is in the high gear, the second gear stage 902E and the third gear stage 903E are engaged. The output 922 from the motor rotates the second gear stage 902E and the third gear stage 903E, which directly rotates the output shaft. When the transmission is in the low gear, the first gear stage 901E, the second gear stage 902E, and the third gear stage 903E are engaged. The output 923 from the motor rotates the first gear stage 901E, the second gear stage 902E, and the third gear stage 903E. The first gear stage 901E, the second gear stage 902E, and the third gear stage 903E subsequently rotate the output shaft of the actuator at a higher torque and lower speed.

[0216] Figures 16A-20CEmbodiments of a transmission are shown that are planetary transmissions. In other embodiments, the transmission can include other epicyclic gear sets (e.g., strain wave), compound planetary gear sets, or non-epicyclic gear sets (e.g., spur gear sets). These gear sets can be used directly or in combination with each other.

[0217] Figure 21A A switchable two-speed transmission 900F is shown that includes a first gear stage 901F, a second gear stage 902F, a stage one switch 905, a ring gear engagement 910, and a planetary gear engagement 915. In this embodiment, the first gear stage 901F includes a strain wave stage, and the second gear stage 902F, which includes a switchable planetary stage, can be engaged and disengaged from the strain wave stage 901F. When the transmission is in the high speed gear, the first gear stage 901F is engaged. The output 921 from the motor rotates the first gear stage 901F, which directly rotates the output shaft. When the transmission is in the low speed gear, both the first gear stage 901F and the second gear stage 902F are engaged. The output 922 from the motor rotates the first gear stage 901F and the second gear stage 902F, which rotates the output shaft of the actuator at a relatively higher torque and lower speed.

[0218] Figure 22 is a schematic diagram of an embodiment of a control system 1000. The control system 1000 can be used to control various prosthetic fingers described herein. For example, the control system 1000 can be used to control any of the fingers shown and described in Figures 1A-21C and 28A-31C. The control system 1000 can be used to control an actuator of a finger, such as the actuator 700, the actuator 701, the actuator 800, the actuator 1600, or any other actuator or component thereof, such as a motor, a shift mechanism, a transmission, etc., described herein.

[0219] The control system 1000 can be used to prevent or mitigate the effects of wear characteristics of a transmission shift mechanism. The control effects are different from an asynchronous transmission shift solution to a synchronous transmission shift solution. In some embodiments, the shift occurs when the transmission is delivering low torque. This can reduce the effects of wear compared to shifting when low torque or no torque is being delivered. The control system 1000 is one example of a transmission shift control system.

[0220] The control system 1000 includes a first controller 1005, which can be a hand microcontroller. The controller 1005 communicates with and commands a motor controller 1010, which communicates with and controls a motor 1015. The motor speed can be controlled. The start or termination of motor movement can be controlled. The motor 1010 can provide feedback 1017 to the controller 1010 related to the current or voltage, position, movement, non-movement, speed, acceleration, etc. of the motor 1015. The motor controller 1010 can provide feedback to the first controller 1005.

[0221] The motor 1015 communicates with and controls a first gear set 1020 and a direct drive 1025. The first gear set 1020 can be any of the gear sets described herein, such as the first gear stage 715a, 1615a, etc. The direct drive 1025 can directly control the output shaft, for example, without a gear set engagement.

[0222] The control system 1030 can include a transmission 1030 having a clutch and a second gear set 1034. The clutch 1032, such as a dog clutch, can be any of the shift gears or components thereof as described herein, such as the shift dog 725, the shift ring 1625, etc. The clutch 1032 can be closed / disengaged to engage the second gear set 1034. The clutch 1032 can be open / engaged to bypass the engagement of the second gear set 1034.

[0223] The control system 1000 includes first data 1035 related to the finger dynamics, such as position, movement, non-movement, speed, acceleration, force, etc. These and other characteristics of the finger, such as the current grip force of the illustrated finger, can be provided as the first data 1035. This data can be sent to and / or used in the second data 1045, which relates to the torque applied by and / or to the actuator. Such torque can be applied to and / or by the motor 760, 1660, etc. The first data 1035 and the second data 1045 can be analyzed to adjust or continue the torque applied by the actuator. The torque data detected in the data 1045 can be communicated to a transmission controller 1050, which can control the transmission 1030 and also provide feedback to the motor controller 1010.

[0224] The control system 1000 can include only Figure 22 Some of the components illustrated and described. The control system 100 can include additional components, such as a third gear set, other types of data, other controllers, etc.

[0225] Figure 23is a flowchart showing one example method that can be performed using the control system 1000. In some embodiments, the power to the motor is interrupted for a fraction of a second after the shift is initiated or detected by a sensor, allowing the delivered torque to drop before a pulse width modulation (PWM) duty cycle acceleration is applied for the next tens of milliseconds. This acceleration allows the clutch to fully engage before full torque is reapplied to the gear. For example, as shown in Figure 23 is a flowchart showing one example method that can be performed using the control system 1000. In some embodiments, the power to the motor is interrupted for a fraction of a second after the shift is initiated or detected by a sensor, allowing the delivered torque to drop before a pulse width modulation (PWM) duty cycle acceleration is applied for the next tens of milliseconds. This acceleration allows the clutch to fully engage before full torque is reapplied to the gear. For example, as shown in

[0226] Figure 24 is a data graph 1200 showing the input torque 1205 and resulting output torque 1210 response of a two-speed transmission as it switches from a high gear to a low gear and back to a high gear. As mentioned, the control system 100 can be used to reduce input torque during a shift, for example, to reduce wear on mechanical components. The data graph 1200 shows one embodiment of data resulting from a drop in input torque during a gear ratio. When the transmission is in a high gear and the input torque is increasing, the transmission switches to a low gear after the input torque meets a certain threshold. As shown in Figure 24 the input torque 1205 drops during the gear ratio transition. When the transmission is in a low gear and the input torque is decreasing, the transmission switches back to a high gear. At this transition point, the input torque 1205 drops again. The specific values of torque are examples only, and other values can result.

[0227] To prevent the transmission from hunting between gear ratios, the transmission can include a built-in hysteresis. The hysteresis ensures that there is an energy difference between changing from one gear ratio to another. Figure 25 is a graphical representation 1300 of the hysteresis showing the difference in shift force between two gear ratios. As shown in Figure 25As shown, a first threshold force is required to overcome the pre-set shift detent in order to shift from a high speed to a low speed gear, i.e., from a high speed, low torque drive to a high torque, low speed drive. The magnitude of this force can be a function of the torque generated in the finger drive assembly. As shown, the example force is about 26 Newtons (N) of force. Once this shift occurs, as long as the force remains above a second threshold, shown in this example as 23 N, the transmission will remain in the low speed gear. If the force in the transmission drops below the entire second threshold, for example due to a drop in force on the finger, the transmission will shift from the low speed gear back to the high speed gear. The hysteresis is the difference between the first threshold and the second threshold, in this example 3 N. The hysteresis eliminates the possibility of the transmission being in neither the high speed gear nor the low speed gear, a condition that can occur without the built-in hysteresis, and thus the upshift force is the same as the downshift force.

[0228] Figure 26 The shift collar within the transmission is depicted shifting from a first torque and a first speed to produce a second torque and a second speed. For convenience, the shift collar shift process 1400 is described as being performed by the embodiment of the transmission 700 described in the Figures 11A-11E The shift collar shift process 1400 can be performed in other embodiments of the transmissions described herein. At block 1405, the finger actuates at a first torque and a first speed while the transmission is in a high speed gear. The shift collar 725 is mechanically coupled to the output planet carrier 705 to lock the third gear stage 715c. The shift collar 725 is free to rotate, and the output of the motor 760 passes through the first gear stage 715a to the second gear stage 715b. The output of the second gear stage 715b rotates the locked third gear stage 715c, and thus directly rotates the output shaft 705. The transmission 700 can remain in the high speed gear until the input torque reaches a certain threshold.

[0229] At block 1410, the input torque has reached the threshold, for example, after the shift collar 725 is shifted away from the output shaft 705. As described herein, for example, with respect to the embodiment of the transmission 700 described in the Figures 28A-31CFurther in detail, the friction element of shift collar 725 can engage with the spring-loaded friction element of gearset 715c's ring gear 750. As shift collar 725 moves proximally, the transfer of torque to the friction element of ring gear 750 increases proportionally. Shift collar 725 disengages from mechanical connection with output planet carrier 705 and can maintain a frictional connection between the friction element of shift collar 725 and the spring-loaded friction element of output planet carrier 705. As shift collar 725 moves proximally, the transfer of torque from output planet carrier 705 to shift collar 725 can decrease proportionally. Once shift collar 725 has been sufficiently displaced to be in substantial frictional contact with the friction element of gearset 715c beyond the frictional contact of the friction element of output planet carrier 705, the relative velocity of shift collar 725 and ring gear 750 tends to zero. After the elements are synchronized, shift collar 725 is further displaced to mechanically connect with ring gear 750 and impede relative movement between shift collar 725 and ring gear 750. There is no contact between the friction element of shift collar 725 and output planet carrier 705. Shift collar 725 then becomes part of the ring gear of gearset 715c.

[0230] At block 1415, all three gearsets 715a, 715b, 715c are engaged and the finger is actuated at a second torque and a second speed. The second torque is greater than the first torque and the second speed is less than the first speed. Shift collar shift process 1400 has been described as being performed in response to a need to increase torque. However, if a need to decrease torque (i.e., the second torque is less than the first torque) then the process would occur in reverse to the described process. Typically, shift collar 725 shifts distally toward output shaft 705 such that first gearset 715a and second gearset 715b disengage and only third gearset 715c is engaged. In some embodiments, process 1400 can not use synchronization.

[0231] Figure 27 Process 1500 is depicted, in which a shift collar within a transmission shifts in response to a first torque and / or a first speed to produce a second torque and a second speed. This shift collar shift process 1500 occurs in embodiments of transmissions that include feedback sensors, such as the mechanisms described in Figures 13-15 and 28A-31C. At block 1505, the shift collar is shifted in response to a first torque and / or a first speed to produce a second torque and a second speed. The shift collar can be shifted in response to a need to increase torque, a need to decrease torque, or a need to change speed. The shift collar can be shifted in response to a need to increase torque and a need to decrease torque. The shift collar can be shifted in response to a need to increase torque and a need to change speed. The shift collar can be shifted in response to a need to decrease torque and a need to change speed. The shift collar can be shifted in response to a need to change speed. Figure 26Block 1405, as shown, similarly drives the finger. In block 1510, a feedback sensor detects a need to increase torque or speed. The sensor transmits this information to the motor 760 or a processor controlling the shifting. For example, as described above with respect to block 1410, in block 1515, if the sensor detects a need to increase torque, the shift gear 825 shifts. If the sensor detects a need to increase speed, the process is reversed. Typically, the shift gear 725 shifts distally to the output shaft 805, disengaging the first gear stage 715a and the second gear stage 715b and engaging only the third gear stage 715c. Various mechanical and / or electronic force / torque feedback mechanisms described herein can be used in process 1500.

[0232] Figures 28A-28B Various views of another embodiment of an actuator 1600 with three gear stages and synchronization are depicted, which can be used in any prosthetic finger described herein. Figures 28A-28B As shown, actuator 1600 includes output shaft 1605, multi-speed gearbox 1610, and motor 1660. Multi-speed synchronizer gearbox 1610 includes clutch ring 1611, tapered surface 1613, first gear stage 1615a, second gear stage 1615b, third gear stage 1615c, fixed gear ring 1650, friction ring 1621, shift ring 1625 (also called "synchronizer gate"), three sets of ball stops 1687, mounting bracket 1645 for motor 1660, and housing 1655. Each of the three gear stages includes three planetary gears 1617 surrounding a sun gear 1616. Between the gear stages are brackets 1640a and 1640b. In this embodiment, the shift ring 1625 is configured to mesh with the second gear stage 1615b and the third gear stage 1615c, and the fixed gear ring 1650 is configured to mesh with the first gear stage 1615a.

[0233] As previously mentioned, synchronized gearboxes are advantageous because they allow gear sets to synchronize their relative speeds before engagement. The synchronized gear design disclosed herein demonstrates two friction-based synchronization methods, referred to as friction discs and conical interference. For demonstration purposes, the conical interference synchronization method is used to change from a “high” speed ratio (16:1) to a “low” speed ratio (64:1), and the friction disc synchronization method is used to change from 64:1 to 16:1.

[0234] Both methods would benefit from non-Newtonian (shear thickening) lubrication, the advantage of which in the conical interference method is manifested in the exponential increase in shear rate between the two elements' roll gap as the taper of the conical element approaches engagement. This increase in shear allows increased force to be transmitted through the lubricant, thus synchronizing with minimal wear to the conical synchronizing elements. The operation of both synchronization methods will be described independently below, it being understood that one or a combination of both methods can be implemented in a dual speed synchronizer type transmission 1610.

[0235] The conical interference mechanism relies on the interaction between a male and a female conical surface. When the conical surface 1613b of the shift collar 1625 comes into contact with the corresponding conical surface 1613a of the output shaft 1605 head, friction provides the torque necessary to synchronize the output shaft 1605 to the same speed as the second gear stage 1615b, which is set before the teeth 1611a engage with the output spline 1605a.

[0236] In describing the operational phases of conical interference synchronization, the shift collar 1625 and the clutch collar 1611 can be radially fixed, so there is no relative rotational motion. The clutch collar 1611 can translate back and forth along the axis of the transmission and can be actuated by an external force. When the described gear is not engaged, it is assumed for the purposes of this explanation that another gear is engaged.

[0237] Figure 29A A partial cross-sectional view of the output shaft 1605, the output shaft spline 1605a, the clutch collar 1611, the detent 1687, the shift collar 1625, and the conical surfaces 1613a, 1613b is depicted. The operational phases of conical interference synchronization are illustrated in Figures 29B-29D with forces F1, F2 and movements indicated by arrows. As Figures 29B-29D shown, the conical interference synchronization, as Figure 29B shown, begins with the output shaft 1605 free to rotate independently of the clutch collar 1611 and the shift collar 1625. In addition, all three gear stages 1615a, 1615b, 1615c (not shown) are engaged.

[0238] In Figure 29CA second phase of conical interference synchronization is depicted in FIG. 16. A force F1 is applied to the clutch ring 1611 which translates the clutch ring 1611 along the gearbox center axis. Force F1 can be applied by an actuator or other mechanism as described herein, such as a linear motor or shape memory alloy. One or more ball detents 1687 bear the shift ring 1625 along the same axis as the clutch ring 1611. Axial movement of the clutch ring 1611 and shift ring 1625 causes the third gear stage 1615c to disengage. The concave cone 1613b of the shift ring 1625 is in frictional contact with the convex cone 1613a of the output shaft 1605. Force F1 transmitted from the clutch ring 1611, through the ball detents 1687, pushes the shift ring 1625 into the output shaft 1605 with sufficient force that the friction between the two cones inhibits relative motion, thereby synchronizing the output shaft 1605 with the shift ring 1625 and clutch ring 1611.

[0239] In Figure 29D A third phase of conical interference synchronization is depicted in FIG. 17. Another force F2 is applied to the clutch ring 1611, overcoming the reaction force from the ball detents 1687. Force F2 can be applied by an actuator or other mechanism as described herein. Release of the ball detents 1687 causes the clutch ring 1611 to translate further axially, independent of the shift ring 1625. Due to the increased axial displacement, the splines 1611a of the clutch ring 1611 engage the splines 1605a of the output shaft 1605, thereby rotationally locking the two components together. The shift ring 1625, clutch ring 1611, and output shaft 1605 now rotate as one, resulting in a "high gear" where only the first and second gear stages 1615b are engaged. However, if the force applied to the clutch ring 1611 is reduced, the process will be reversed from that described. Typically, the clutch ring 1611 moves proximally and the ball detents 1687 engage the shift ring 1625. Continued distal movement of the clutch ring 1611 with the shift ring 1625 causes the conical surfaces 1613a, 1613b to move apart, which allows the output shaft 1650 to rotate independent of the clutch ring 1611 and shift 1625.

[0240] Figure 30A A partial cross-sectional view of the clutch ring 1611, detents 1687, shift 1625, friction ring 1621, ring gear splines 1650a, and stationary ring gear 1650 is depicted in FIG. 18. The operational phases of the friction disc synchronization are illustrated in Figures 30B-30D FIG. 19 with forces F3, F4 and arrows indicating movement. The friction disc mechanism relies on the frictional contact of the shift ring 1625 and the friction ring 1621 mounted on the stationary ring gear 1650. When the shift ring 1625 is in contact with the friction ring 1621, the frictional force provides the torque necessary to synchronize the relative velocities of the shift ring 1625 and the stationary ring gear 1650 before the ring gear splines 1650a are engaged.

[0241] In describing the operational phases of the friction disc synchronisation, the shift ring 1625 and the clutch ring 1611 can be radially fixed so that there is no relative rotational movement. The clutch ring 1611 can be translated back and forth along the axis of the gearbox and can be actuated by an external force. When the described gear is not engaged, for the purpose of this explanation, it is assumed that another gear is already engaged.

[0242] As Figures 30B-30D illustrated, the friction disc synchronisation, as Figure 30B illustrated, starts with the shift ring 1625 and the clutch ring 1611 being locked to the output shaft 1605. In this position, the shift ring 1625 and the clutch ring 1611 are free to rotate together independently of the stationary ring gear 1650. The first gear stage 715a and the second gear stage 715b are engaged.

[0243] In the second phase of the friction disc synchronisation, as Figure 30C illustrated, a force F3 is applied to the clutch ring 1611 which translates the clutch ring 1611 along the central axis of the gearbox. This spherical detent set 1687 carries the shift ring 1625 along the same axis as the clutch ring 1611. The leading edge of the shift ring 1625 is in frictional contact with the friction ring 1621 mounted on the stationary ring gear 1650. The force F3 transmitted from the clutch ring 1611 pushes the shift ring 1625 into the friction ring 1621 with sufficient force through the spherical detent 1687 so that the friction between the two surfaces inhibits relative movement, thereby synchronising the rotational speed of the shift ring 1625 with the clutch ring 1611 with the stationary ring gear 1650.

[0244] In the third phase of the friction disc synchronisation, as Figure 30D illustrated, another force F4, possibly greater than the force F3, is applied to the clutch ring 1611, thereby overcoming the spherical detent 1687. The release of the spherical detent 1687 causes the clutch ring 1611 to translate further axially independently of the shift ring 1625. Due to the increased axial displacement, the splines 1611a of the clutch ring 1611 engage the splines 1650a of the stationary ring gear 1650 (as Figure 30A illustrated), thereby rotationally locking the two components together. The shift ring 1625 and the clutch ring 1611 are locked to the stationary ring gear 1650, thereby forming a “low gear” with all three gear stages 1615a, 1615b, 1615c engaged.

[0245] Figures 31A-31CA comparison of three different detent configurations 1705, 1715, 1725 and the resulting corresponding force vs. displacement force plots 1700, 1710, 1720 are depicted. The detent configuration impacts the amount of force and the transfer of force to the friction element before the spline engages. Various designs depict embodiments with a “V” shaped groove with a spherical detent 1687, which can be 90°, or greater or less than 90°. Different embodiments result in different force curves. The detent 1687 can be other suitable features such as a pin. The detent 1687 is in an embodiment of a notch in each configuration 1705, 1715, 1725.

[0246] The force curve is important for controlling the dynamics of a shift. A constant force helps to maintain friction during engagement and disengagement, but results in a constant force being required by the transmission to “hold” it in gear. Conversely, an instantaneous curve allows the transmission to hold the gear without a constant force shift, but if the force is applied incorrectly, the friction in the synchronizing element can drop, allowing for a loss of synchronization before the clutch ring spline engages. Embodiments described herein include an action to increase the force transfer to a threshold, at which point the force drops to zero.

[0247] As shown in FIG. 17A, Figure 31A For configuration 1705, the detent 1687 is in a notch 1626A. The notch 1626A can be a groove or a depression. The notch 1626A can be sloped in a deep “V” shape relative to the cross-sectional width of the detent 1687. The corresponding force plot 1700 resulting for detent configuration 1705 includes a relatively steep force vs. displacement slope, requiring a greater force and covering a shorter distance of displacement to overcome the resistance of the notch 1626A acting on the detent 1687, as compared to a relatively shallow “V” shape or a notch such as Figure 31B

[0248] Two alternative detent profiles 1715, 1720 are depicted. As shown in FIG. 17B, Figures 31B-31C The detent 1687 is in a notch 1626B. The notch 1626B can be a groove or a depression. The notch 1626B can be sloped in a shallow “V” shape relative to the cross-sectional width of the detent 1687. As shown in FIG. 17B, Figure 31B The corresponding force plot 1710 for detent configuration 1715 includes a relatively less steep force vs. displacement slope, applying a gentler force, covering a relatively longer distance of displacement to overcome the resistance of the notch 1626A acting on the detent 1687, as compared to a deeper “V” shape or a notch such as Figure 31B Figure 31A

[0249] As shown in FIG. 17C, Figure 31C ​​As shown, the stopper 1687 is located in the notch 1626C. The notch 1626C can be a two-stage, e.g., double-depth, groove or recess. Relative to the cross-sectional width of the stopper 1687, the notch 1626C can have a narrower "V"-shaped, shallow pit therein. As shown, the corresponding force diagram 1720 of the stopper configuration 1725 has two stages. In the first stage (on the left side of the force diagram 1720), the force rises rapidly to overcome the "V"-shaped resistance acting on the stopper 1687, and then in the later displacement, the force rises again to overcome the pit edge resistance acting on the stopper 1687. Figure 31C

[0250] Figures 32A-32B are various views of another embodiment of a prosthetic finger 1800. The prosthetic finger 1800 can be used with the system 100 or the hand 200. The finger 1800 includes a mount 1810, a proximal segment 1820, a middle segment 1830, and a distal segment 1840. The mount 1810 and the segments 1820, 1830, 1840 can have the same or similar features and / or functions as the mounts 350, 410, 510, 610 and the segments 320, 330, 340, 420, 430, 440, respectively, and thus can articulate, e.g., rotate relative to one another, etc.

[0251] The finger 1800 includes mechanically connected rigid links, including a proximal link 1860 and a distal link 1870. The links 1860, 1870 can have the same or similar features and / or functions as the links 360, 370. For example, the mount 1810 can be rotatably attached to a proximal end of the proximal link 1860 about a connector 1858. The proximal link 1860 is rotatably attached to the middle segment 1830 of the finger 1800 about a pivot 1866. The proximal link 1860 can include a bend, where a proximal end of the proximal link 1860 extends along a first axis and a distal end of the proximal link extends along a second axis at an angle to the first axis. The pivot 1866 can be located at or near an apex of the bend of the proximal link 1860. A distal end of the proximal link 1860 is rotatably attached to a proximal end of the distal link 1870 about a connector 1868. A distal end of the distal link 1870 is rotatably attached to the distal segment 1840 of the finger 1800 about a pivot 1876.

[0252] The finger 1800 includes an actuator 1804, which can have the same or similar features and / or functions as the actuators 301, 404, 501, 601, 700, 701, 800, 1600, unless otherwise noted. For example, the actuator 1804 can include a motor 1815 powered by a battery, which can be within the hand or elsewhere. The motor 1815 can have an output shaft extending distally therefrom, for example, and mechanically connected with the off-axis shaft 1809.

[0253] ​The actuator 1804 includes a worm gear 1812 and a worm 1814, which can have the same or similar features and / or functionality as the worm gear 412 and the worm 414, respectively, unless otherwise noted. For example, the worm 1814, which has external threads 1819 thereon, can be mechanically coupled to the shaft 1809. Actuation of the motor 1815 causes motion to be transmitted through a pinion gear 1813 (see Figure 33B and Figure 33C ) to the shaft 1809 to rotate the worm 1814. The worm gear 1812 can have external teeth 1816 thereon. In some embodiments, only a portion of the outer circumference of the worm gear 1812 includes the external teeth 1816 (e.g., the portion of the outer circumference of the worm gear 1812 adjacent to the worm 1814). The remainder of the outer circumference of the worm gear 1812 can be smooth or toothless. Such a configuration can advantageously allow for a compact worm gear 1812 and worm 1814 system. The threads 1819 (see Figure 33B and Figure 33C ) of the worm 1814 contact the teeth 1816 of the worm gear 1812 to cause rotational motion of the worm gear 1812. The worm gear 1812 can be rotated in a first rotational direction to cause a first rotation of the finger 1800 in a first direction (e.g., closing the finger 1800). The worm gear 1812 can be rotated in a second rotational direction opposite the first rotational direction to allow a second rotation of the finger 1800 in a second direction opposite the first direction (e.g., opening the finger).

[0254] Figures 33A-33C are various views of the actuator 1804 of the finger 1800. Figure 33A is a partial exploded view of the actuator 1804, Figure 33B and 33C show the actuator 1804 with various features removed or hidden for clarity. The actuator 1804 of the finger 1800 can include a central shaft 1890 having a drive key 1892 configured to engage a portion of the proximal segment 1820 of the finger 1800. For example, in some embodiments, the drive key 1892 is positioned on an outer surface of the central shaft 1890 and has an extension length and width that protrude outward from the outer surface of the central shaft 1890. An inner surface 1822 of the proximal segment 1820 of the finger 1800 can include a mating feature 1824 that corresponds in shape to the shape of the drive key 1892 of the central shaft 1890, such as a recess, opening, and / or groove. The mating feature 1824 of the proximal segment 1820 can receive the drive key 1892 of the central shaft 1890 therein to transmit rotational force from the central shaft 1890 to the proximal segment 1820. In some embodiments, the ratio of the angle of rotation of the drive key 1892 to the angle of rotation of the proximal segment 1820 is 1 : 1.

[0255] In some embodiments, the center shaft 1890 includes a first drive key 1892 that protrudes outward from a first outer surface of the center shaft 1890 in a first direction, and a second drive key 1892 that protrudes outward from a second outer surface of the center shaft 1890 in a second direction opposite the first direction. The proximal section 1820 can include a first inner surface 1822 having a first mating feature 1824 for receiving the first drive key 1892, and a second inner surface 1822 having a second mating feature 1824 for receiving the second drive 1892.

[0256] In some embodiments, the center shaft 1890 can include one or more drive tabs 1894. Each drive tab 1894 can have an arcuate length and width that protrudes axially from an inner surface of the center shaft 1890 and extends. In some embodiments, the center shaft 1890 includes a first drive tab 1894 and a second drive tab 1894 positioned radially opposite the first drive tab 1894.

[0257] In some embodiments, the worm gear 1812 can include one or more corresponding drive tabs 1818. For example, the worm gear 1812 can include a first drive tab 1818 and a second drive tab 1818 positioned radially opposite the first drive tab 1818. The drive tabs 1818 of the worm gear 1812 can extend radially inward from an inner surface of the worm gear 1812 toward a central axis of the worm gear 1812. The drive tabs 1818 of the worm gear 1812 can be positioned between the first and second drive tabs 1894 of the center shaft 1890. In some embodiments, one or more drive tabs 1894 of the center shaft 1890 engage (e.g., contact, abut, connect, etc.) one or more drive tabs 1818 of the worm gear 1812 to transfer rotational force of the worm gear 1812 to the center shaft 1890.

[0258] The drive mechanism of the finger 1800 can include a spring 1803 (e.g., a torsion spring). The spring 1803 can be coupled to (e.g., circumferentially surround) the axially extending member 1802, which extends axially along the central axis of the worm gear 1812 and / or the central shaft 1890. The spring 1803 can be configured to rotationally bias the worm gear 1812 in an angular direction to maintain the relative position of the central shaft 1890 and the worm gear 1812. For example, the spring 1803 can include a flange 1808 that extends further radially outward than the rest of the spring 1803. The flange 1808 can engage one of the drive tabs 1818 of the worm gear 1812. For example, in some embodiments, the worm gear 1812 and the central shaft 1890 are positioned such that one of the drive tabs 1894 of the central shaft 1890 abuts a first surface of one of the drive tabs 1818 of the worm gear 1812, and the flange 1808 abuts a second surface of the drive tab 1818 that is opposite the first surface of the drive tab 1818. This configuration enables rotational force of the worm gear 1812 to be transmitted to the central shaft 1890 while maintaining the relative position of the worm gear 1812 and the central shaft 1890. As described below, this configuration also allows the finger 1800 to close independent of the drive mechanism of the finger 1800.

[0259] In some embodiments, the finger 1800 can open and / or close with or without use of the actuator 1804. For example, the finger 1800 can have a worm-driven mode of movement (e.g., driven by the actuator 1804) and a manual mode of movement (e.g., driven by an external force). When the finger 1800 is in the open position, application of an external force to the finger 1800 in the closing direction can cause the finger 1800 to close to the closed position. In some embodiments, in the manual mode of movement, unlike the worm-driven mode of movement, the actuator 1804 does not drive the worm gear 1812. For example, in the manual mode of movement, the actuator 1804 and the worm gear 1812 remain stationary. In the manual mode of movement, the central shaft 1890 rotates in response to the external force applied to the finger 1800, while the worm gear 1812 remains stationary because the spring flange 1808 allows rotation when its spring biasing force is overcome. Rotation of the central shaft 1890 can cause the segments 1820, 1830, 1840 of the finger 1800 to rotate to the closed position. In the manual mode of movement, the protrusions 1818 of the worm gear 1812 can limit the range of rotation of one or more of the drive tabs 1894 of the central shaft 1890, and thus limit the range of rotation of the central shaft 1890. As a result of the external force applied to the finger 1800, the spring 1803 can rotate and store energy as the finger 1800 is manually moved to the closed position. In some embodiments, when the external force is removed from the finger 1800, the spring 1803 can use the stored potential energy to rotate and cause the finger 1800 to return to the open position.

[0260] The manual movement mode of the finger 1800 can be advantageously used as a mechanical protection system when an external force is acting on the finger 1800, for example when a user falls on the finger 1800 or exerts pressure on the finger 1800 to rise from a chair, etc. Manual closure of the finger 1800 can allow the external load to be supported by components of the finger 1800 other than the drive mechanism (e.g., the gearbox). This can prevent damage that can be caused to the drive mechanism of the finger 1800.

[0261] Figure 34 The locations of the encoders 1805, 1806 within the finger 1800 are shown. In some embodiments, the finger 1800 includes multiple encoders 1805, 1806 mounted to the gearbox. For example, in some embodiments, the finger 1800 includes a first type of encoder for the worm drive movement mode and a second type of encoder for the manual movement mode. As shown, the finger 1800 can include a potentiometer tape encoder 1806 and a magnetic encoder 1805. The potentiometer tape encoder 1806 can be coupled to the worm gear 1812. The magnetic encoder 1805 can be positioned between the potentiometer tape encoder 1806 and the pinion gear 1813. The potentiometer tape encoder 1806 can measure the position of the finger 1800 by measuring the absolute position of the motor driver. The magnetic encoder 1805 can be an absolute Hall effect magnetic encoder. The magnetic encoder 1805 can measure the position of the finger 1800 by measuring the rotational degrees of a radially magnetized axial magnet positioned within a member 1802 that extends axially at the center of the central shaft 1890.

[0262] Figure 35 is a cross-sectional view of a portion of the finger 1800 showing a waterproof seal 1807 within the finger 1800. In some embodiments, the finger 1800 can be waterproof (e.g., IP68 rated). The finger 1800 can include a seal 1807, such as an O-ring seal, a lip seal, and / or other dynamic seal, to seal components within the central shaft 1890 from water ingress. For example, the seal 1807 can be positioned in a gap between the central shaft 1890 and the mounting 1810.

[0263] In some embodiments, the finger 1800 can include any of the various embodiments of fingers and actuators or features thereof described herein. The finger 1800 can include the actuator 301, 404, 501, 601, 700, 701, 800, or 1600 or features thereof. For example, the finger 1800 can be modified to include the motor 305, 405, 505, 605, 760, or 1660 in place of the motor 1815. Other suitable substitutions or modifications of the finger 1800 using any of the prosthetic features described herein can be implemented in various embodiments.

[0264] Figures 36A-36B FIGS. 19A-19C are various views of another embodiment of a prosthetic finger 1900. The prosthetic finger 1900 can be used with the system 100 or the hand 200. The prosthetic finger 1900 includes a mount 1910, a proximal segment 1920, a middle segment 1930, and a distal segment 1940. The mount 1910 and the segments 1920, 1930, 1940 can have the same or similar features and / or functionality as the mounts 350, 410, 510, 610, 1810 and the segments 320, 330, 340, 420, 430, 440, 1820, 1830, 1840, respectively, and thus can articulate, e.g., rotate relative to one another, etc.

[0265] The finger 1900 includes mechanically linked links, including a proximal link 1960 and a distal link 1970. In some embodiments, the links 1960, 1970 can be a single continuous link. The links 1960, 1970 can have the same or similar features and / or functionality as the links 360, 370, 1860, 1870. For example, the mount 1910 can be rotatably attached to a proximal end of the proximal link 1960 about a connector 1958, e.g., a pin. The connector 1958 can include a rotational joint such that the link 1960 can rotate relative to the mount 1910 about the connector 1958.

[0266] The proximal link 1960 is rotatably attached to the middle segment 1930 of the finger 1900 about a pivot 1966. The proximal link 1960 can include a bend, where a proximal end of the proximal link 1960 extends along a first axis and a distal end of the proximal link 1960 extends along a second axis at an angle to the first axis. The pivot 1966 can be located at or near an apex of the bend of the proximal link 1960. The distal end of the proximal link 1960 is attached to a proximal end of the distal link 1970 about a connector 1968. The connector 1968 can include a bearing and a pin, where the pin is configured to act as a constrained pin (e.g., the pin is welded in place). A distal end of the distal link 1970 is rotatably attached to the distal segment 1940 of the finger 1900 about a pivot 1976. The distal link 1970 can bend in the event that a rotational load applied to the finger 1900 exceeds a threshold load. As further described, the bend in the link can have elasticity to absorb such loads.

[0267] The finger 1900 includes an actuator 1904, which can have the same or similar features and / or functionality as the actuators 301, 404, 501, 601, 700, 701, 800, 1600, 1804, unless otherwise noted. For example, the actuator 1904 can include a motor 1915 powered by a battery, which can be in the hand or elsewhere.

[0268] The actuator 1904 includes a worm gear 1912 and a worm 1914, which can have the same or similar features and / or functionality as the worm gear 412, 1812 and the worm 414, 1814, respectively, unless otherwise noted. For example, the worm 1914, which has external threads 1919 thereon, can be mechanically coupled to the shaft 1909. Actuation of the motor 1915 causes motion to be transmitted through one or more transmission gears 1992A, 1992B, 1992C (see Figure 41B ) and / or one or more other gears (e.g., in a planetary gearbox 1903) to the shaft 1909 to rotate the worm 1914. The worm gear 1912 can have external teeth 1916 thereon. In some embodiments, only a portion of the outer circumference of the worm gear 1912 includes the external teeth 1916 (e.g., the portion of the outer circumference of the worm gear 1912 adjacent to the worm 1914). The remainder of the outer circumference of the worm gear 1912 can be smooth or toothless. Such a configuration can advantageously allow for a compact worm gear 1912 and worm 1914 system. The threads 1919 (see Figure 37A , 37C , 41A, 41B) of the worm 1914 contact the teeth 1916 of the worm gear 1912 to cause rotational motion of the worm gear 1912. The worm gear 1912 can rotate in a first rotational direction to cause a first rotation of the finger 1900 in a first direction (e.g., closing the finger 1800). The worm gear 1912 can rotate in a second rotational direction opposite the first rotational direction to allow a second rotation of the finger 1900 in a second direction opposite the first direction (e.g., opening the finger).

[0269] Figures 37A-37B The shapes of the proximal link 1960 and the distal link 1970, as well as the relationship between the proximal link 1960 and the distal link 1970, are shown. The distal link 1970 can be arcuate and / or curved (see Figures 37A-37B ). This can advantageously reduce the visibility of the distal link 1970 and / or the proximal link 1960 during rotation of the prosthetic finger 1900. For example, as shown in Figures 38A-38C , the distal link 1970 and / or the proximal link 1960 can be hidden within the interior volume of the segments 1920, 1930, 1940 as the segments 1920, 1930, 1940 rotate (e.g., the links 1960, 1970 can not protrude from the finger 1900 during flexion). The distal link 1970 can include additional undulations to increase the spring force of the finger 1900.

[0270] The distal link 1970 can be flexible and / or configured to flex in response to a threshold rotational force applied to the prosthetic finger 1900. The arcuate geometry of the distal link 1970 and / or the elasticity of the material (e.g., titanium) used to form the distal link 1970 can create additional elasticity and / or spring force in the prosthetic finger 1900. For example, as the pin 1901 extending through the pivot 1966 moves closer to (or further from) the pin 1905 extending through the pivot 1976 (see FIG. 38C) during rotation of the finger 1900, the distal link 1970 can create additional spring force in the finger 1900. This can advantageously facilitate return of the finger 1900 from a rotated position and / or provide additional impact load protection for components of the actuator 1904 (e.g., the gearbox 1903). For example, when an external force is acting on the finger 1900 (e.g., when a user closes the finger 1900 in their hand, falls on the finger 1900, or exerts pressure on the finger 1900 to stand up from a chair, etc.), the arcuate distal link 1970 can allow manual movement of the finger 1900 to act as a mechanical protection system. Manual closure of the finger 1900 can allow the external load to be supported by components of the finger 1900 other than the gearbox 1903. This can prevent damage that can be caused to the actuator 1904 of the finger 1900. Figure 37A and 38A -38C) during rotation of the finger 1900, the distal link 1970 can create additional spring force in the finger 1900. This can advantageously facilitate return of the finger 1900 from a rotated position and / or provide additional impact load protection for components of the actuator 1904 (e.g., the gearbox 1903). For example, when an external force is acting on the finger 1900 (e.g., when a user closes the finger 1900 in their hand, falls on the finger 1900, or exerts pressure on the finger 1900 to stand up from a chair, etc.), the arcuate distal link 1970 can allow manual movement of the finger 1900 to act as a mechanical protection system. Manual closure of the finger 1900 can allow the external load to be supported by components of the finger 1900 other than the gearbox 1903. This can prevent damage that can be caused to the actuator 1904 of the finger 1900.

[0271] Figure 37C The actuator 1904 of the finger 1900 is shown with some components removed for clarity. The actuator 1904 can include a spring 1980 (e.g., a tension spring). For example Figure 33C As described above, the spring 1980 can provide similar functionality to the spring 1803, but with an elongated spring instead of a torsion spring. The spring 1980 can be coupled to an inner surface of the worm gear 1912. The spring 1980 can extend circumferentially around the central axis of the worm gear 1912 (e.g., along at least a portion of the inner surface of the worm gear 1912). The spring 1980 can be configured to rotationally bias the worm gear 1912 in an angular direction. The spring 1980 can bias the worm gear 1912 in an open rotational direction. The spring 1980 can bias the worm gear 1912 in a closed rotational direction. The spring 1980 can only move when an external force is applied to the finger 1900 in the closed rotational direction. This configuration can allow the finger 1900 to close independently of the drive mechanism of the finger 1900 (e.g., manual closure), thereby allowing the finger 1900 to utilize the mechanical protection system described above. Use of a tension spring 1980 in the finger 1900 can advantageously reduce the likelihood of fatigue failure of the spring 1980 due to rotation of the finger 1900 and / or increase the number of flexes of the finger 1900 before fatigue failure, thereby increasing the useful life of the mechanical protection system of the finger 1900.

[0272] Figures 39A-39BThe relationship between actuator 1904, proximal segment 1920, and mounting member 1910 is illustrated. Some portions of actuator 1904, such as worm gear 1912, may be configured to be coupled to proximal segment 1920 and / or mounting member 1910. Proximal segment 1920 may include a first side 1920A (e.g., on the drive side 1982 of finger 1900) and a second side 1920B (e.g., on the support side 1984 of finger 1900). Figure 39A As shown, the worm gear 1912 can be configured to be disposed between a first side 1920A of the proximal segment 1920 and the mounting member 1910. A cover 1902 can be coupled to the first side 1920A of the proximal segment 1920 (e.g., coupled to the outside of the first side 1920A). The cover 1902 can be configured to protect a component disposed within the finger 1900. A bearing pin 1988 having a shaft 1990 can be configured to extend inwardly from a second side 1920B of the proximal segment 1920 through at least a portion of the mounting member 1910 and the actuator 1904 (e.g., through at least a portion of the worm gear 1912). The bearing pin 1988 can help secure components of the finger 1900 and / or seal an opening in the support side 1984 of the finger 1900 (e.g., an opening in the second side 1920B of the proximal segment 1920). The shaft 1990 can have a first portion and a second portion, the first portion having a first diameter and the second portion having a second diameter larger than the first diameter. This can advantageously reduce the likelihood that the second side 1920B of the proximal segment 1920 will separate from the bearing pin 1988 when a load is applied to the finger 1900. The outer surface of the bearing pin 1988 can be made of titanium, and the shaft 1990 can be made of steel.

[0273] like Figure 39A As shown, actuator 1904 may include thrust bearing 1993, which is configured to face the inner surface of mounting member 1910. Thrust bearing 1993 may include multiple ball bearings. Thrust bearing 1993 may be configured to provide rotational motion while primarily bearing axial force. Thrust bearing 1993 may be a thrust ball bearing, wherein the bearing balls are supported in rings. The bearings may be ball, cylindrical roller, tapered roller, spherical roller, fluid, magnetic, or other types of thrust bearings.

[0274] Figure 39BThe mating portions of the proximal section 1920, actuator 1904, and mount 1910 are shown. Actuator 1904 can be configured to engage mount 1910 via mating feature 1911. For example, mating feature 1911 may include a recess in mount 1910, sized and / or shaped to receive at least a portion of worm gear 1912. A first side 1920A of the proximal section 1920 may include mating feature 1922, such as a protrusion or recess, corresponding to mating feature 1913 of actuator 1904, such as a corresponding recess or protrusion. The mating feature 1922 of the first side 1920A of the proximal section 1920 may include an axially inwardly extending protrusion. The mating feature 1922 may include a tab 1924 extending radially away from the protrusion and having a hole 1926. The mating feature 1913 of the actuator 1904 may include a recess sized and / or shaped to receive at least a portion of the mating feature 1922 of the proximal segment 1920. The mating feature 1913 of the actuator 1904 may include a protrusion 1917 configured to extend toward and be received in a hole 1926 of the tab 1924 of the proximal segment 1920. This arrangement can advantageously enable rotational motion of the worm gear 1912 to be transmitted to a first side 1920A of the proximal segment 1920 (e.g., on the actuator side 1982 of the finger 1900).

[0275] like Figures 40A-40F As shown, finger 1900 may have a cantilever drive arrangement (e.g., a single-sided drive arrangement), wherein actuator 1904 is configured to rotate proximal segment 1920 via drive side 1982 of finger 1900. For example, as Figures 40A-40B As shown, the line of action of the actuation force or force path 1986 can extend along the first lateral side 1920A of the proximal segment 1920. The first side 1920A of the proximal segment 1920 can be configured to transmit actuation to the rest of the proximal segment 1920. This drive arrangement can advantageously improve the efficiency of the finger 1900 during normal use.

[0276] The support side 1984 of the finger 1900, located opposite the drive side 1982, can be a non-contact support side during normal use, for example, when no lateral load exceeding a threshold lateral load is applied to the finger 1900. For example, when no lateral load exceeding a threshold lateral load is applied to the finger 1900, the support side 1984 may not increase frictional losses or nominal frictional losses to the finger 1900. During normal use, a clearance may exist so that the exterior of the bearing pin 1988 may not contact other parts of the finger 1900. Figure 40EAs shown, when the finger 1900 is in an unloaded configuration, e.g., where no lateral load exceeding a threshold lateral load is applied to the finger 1900, a gap 1991 laterally adjacent to the bearing pin 1988 exists at the support side 1984 of the finger 1900. As used herein, "lateral" can refer to a direction generally parallel to the rotational axis of the finger segment. The gap 1991 (e.g., void) around the bearing pin 1988 can allow the bearing pin 1988 to freewheel and / or rotate freely.

[0277] The support side 1984 of the finger 1900 (e.g., the second side 1920B of the proximal segment 1920) can be configured to provide support to the finger 1900 in response to a lateral load applied to the finger 1900 (e.g., to the distal segment 1940, the middle segment 1930, and / or the proximal segment 1920) exceeding a threshold lateral load. The first bearing surface 1973 and the second bearing surface 1975, which are laterally separated by a gap during normal loading operations that do not satisfy the threshold lateral load, can come into contact with each other under loading conditions that satisfy the threshold lateral load. The threshold lateral load can be one-quarter, one-half, three-quarters, one, two, three, four, five, or more pounds. For example, as shown in FIG. 19B, the first bearing surface 1973 and the second bearing surface 1975 of the bearing pin 1988 can be in contact with each other when a lateral load F exceeding the threshold lateral load is applied to the finger 1900. Figure 40F As shown schematically, when the finger 1900 is in a loaded configuration (e.g., when a lateral load F exceeding a threshold lateral load is applied to the finger 1900), the proximal segment 1920 is configured to flex (e.g., deflect) laterally to close the gap 1991 between the bearing pin 1988 and the opposing surface and increase rotational friction of the finger 1900. The proximal segment 1920 can be configured to deflect to close the gap 1991 between the first bearing surface 1973 of the bearing pin 1988 and the second bearing surface 1975 at the second side 1920B of the proximal segment 1900 (see bearing surfaces 1973, 1975 in FIG. 19B). The first bearing surface 1973 of the bearing pin 1988 can be an outer radial edge of the bearing pin 1988. The second bearing surface 1975 of the second side 1920B of the proximal segment 1920 can be a corresponding inner radial edge of the opening of the second side 1920B (e.g., configured to receive the bearing pin 1988). The bearing pin 1988 can be configured to slide axially along the rotational axis of the bearing pin 1988 to contact the second side 1920B (e.g., the second bearing surface 1975) of the proximal segment 1920 when the proximal segment 1920 flexes laterally. When the proximal segment 1920 deflects, the finger 1900 is still rotatable but receives support from the additional bearing surface formed by the bearing pin 1988 (see force path 1987 in FIG. 19B). Figure 39A As shown schematically, when the finger 1900 is in a loaded configuration (e.g., when a lateral load F exceeding a threshold lateral load is applied to the finger 1900), the proximal segment 1920 is configured to flex (e.g., deflect) laterally to close the gap 1991 between the bearing pin 1988 and the opposing surface and increase rotational friction of the finger 1900. The proximal segment 1920 can be configured to deflect to close the gap 1991 between the first bearing surface 1973 of the bearing pin 1988 and the second bearing surface 1975 at the second side 1920B of the proximal segment 1900 (see bearing surfaces 1973, 1975 in FIG. 19B). The first bearing surface 1973 of the bearing pin 1988 can be an outer radial edge of the bearing pin 1988. The second bearing surface 1975 of the second side 1920B of the proximal segment 1920 can be a corresponding inner radial edge of the opening of the second side 1920B (e.g., configured to receive the bearing pin 1988). The bearing pin 1988 can be configured to slide axially along the rotational axis of the bearing pin 1988 to contact the second side 1920B (e.g., the second bearing surface 1975) of the proximal segment 1920 when the proximal segment 1920 flexes laterally. When the proximal segment 1920 deflects, the finger 1900 is still rotatable but receives support from the additional bearing surface formed by the bearing pin 1988 (see force path 1987 in FIG. 19B). Figure 40F As shown schematically, when the finger 1900 is in a loaded configuration (e.g., when a lateral load F exceeding a threshold lateral load is applied to the finger 1900), the proximal segment 1920 is configured to flex (e.g., deflect) laterally to close the gap 1991 between the bearing pin 1988 and the opposing surface and increase rotational friction of the finger 1900. The proximal segment 1920 can be configured to deflect to close the gap 1991 between the first bearing surface 1973 of the bearing pin 1988 and the second bearing surface 1975 at the second side 1920B of the proximal segment 1900 (see bearing surfaces 1973, 1975 in FIG. 19B). The first bearing surface 1973 of the bearing pin 1988 can be an outer radial edge of the bearing pin 1988. The second bearing surface 1975 of the second side 1920B of the proximal segment 1920 can be a corresponding inner radial edge of the opening of the second side 1920B (e.g., configured to receive the bearing pin 1988). The bearing pin 1988 can be configured to slide axially along the rotational axis of the bearing pin 1988 to contact the second side 1920B (e.g., the second bearing surface 1975) of the proximal segment 1920 when the proximal segment 1920 flexes laterally. When the proximal segment 1920 deflects, the finger 1900 is still rotatable but receives support from the additional bearing surface formed by the bearing pin 1988 (see force path 1987 in FIG. 19B).

[0278] A single-sided drive arrangement can advantageously allow the finger 1900 to be more compact (e.g., narrower), and / or can provide additional space within the finger 1900 for other components (e.g., bearings). For example, a single-sided drive arrangement can reduce the number of dynamic seals of the finger 1900 (e.g., the drive mechanism can include only one dynamic seal).

[0279] Figures 41A-41B A parallel arrangement of a gearbox 1903, e.g., a planetary gearbox, and a motor 1915 of an actuator 1904 is shown. The actuator 1904 can include the motor 1915, the planetary gearbox 1903, and one or more transmission gears 1992A, 1992B, 1992C disposed in a transmission gearbox 1906. The motor 1915 and the planetary gearbox 1903 can be positioned parallel to one another and connected by the one or more transmission gears 1992A, 1992B, 1992C (see Figure 41B ). The motor 1915 and the planetary gearbox 1903 can extend longitudinally in directions parallel to one another and parallel or substantially parallel to a proximal segment of the finger when straightened (see Figure 38A ). For example, an output shaft of the motor 1915 can be in mechanical communication with the planetary gearbox 1903 through a series of transmission gears 1992A, 1992B, 1992C that extend perpendicular to the motor 1915 and the planetary gearbox 1903. The gear 1992A can have a smaller diameter than the transmission gear 1992B, which is coupled to the output shaft of the motor 1915, between the output shaft of the motor 1915 and an input shaft of the planetary gearbox 1903, and / or which has a smaller diameter than the gear 1992C, which is coupled to the input shaft of the planetary gearbox 1903. The gears 1992A, 1992B, 1992C can be disposed in the transmission gearbox 1906 below (e.g., proximate to) the motor 1915 and the planetary gearbox 1903, and can be protected (e.g., enclosed) by a housing 1908 of the transmission gearbox 1906. The actuator 1904 arrangement with the motor 1915 extending parallel to the planetary gearbox 1903 can advantageously allow the actuator 1904 to be more compact (e.g., shorter, have a smaller volume, etc.). In some embodiments, the finger 1900 can include a transmission belt instead of one or more of the transmission gears 1992A, 1992B, 1992C.

[0280] The finger 1900 can include one or more position encoders (e.g., one sensor, two sensors, three sensors, four sensors, etc.), such as a Hall effect sensor configured to measure a position of the finger 1900. The sensor can be coupled to or integrated within the motor 1915. For example, the sensor can be disposed at a proximal end of the motor 1915. The sensor can measure a position (e.g., a relative position and / or an absolute position) of a rotor in the motor 1915. The rotor position measurements can be used to calculate a position of the finger 1900.

[0281] Figures 42A-42C A fingertip assembly 1994 is shown. For clarity, Figure 42B Certain portions of the fingertip assembly 1994 are omitted for clarity. The fingertip assembly 1994 can include a fingertip insert 1996 configured to be received in a corresponding channel in the distal segment 1940 of the finger 1900. The fingertip insert 1996 can be replaced and / or removed from the distal segment 1940. The fingertip assembly 1994 can include a support member 1997 coupled to or integral with the fingertip insert 1996. The support member 1997 can be configured to extend proximally from the fingertip insert 1996 through an opening 1942 in the distal segment 1940 of the finger 1900. The support member 1997 can act as an assist assembly to position the fingertip insert 1996 within the distal segment 1940 of the fingertip insert 1996. As Figure 42C A portion of the support member 1997 shown can be removed and / or shortened after the fingertip insert 1996 has been positioned. A distal portion of the distal segment 1940 can be configured to protrude distally beyond the fingertip insert 1996 when the fingertip insert 1996 is compressed (e.g., when a user picks up an object to apply pressure to the fingertip insert 1996) when the fingertip insert 1996 is coupled to the distal segment 1940. This configuration can advantageously allow a user to pick up small objects.

[0282] The fingertip insert 1996 can be configured to be coupled to a pivot assembly 1998. The pivot assembly 1998 can be configured to be coupled to and rotate about the pivot 1976. Rotation of the pivot assembly 1998 about the pivot 1976 can cause the fingertip insert 1996 and / or the distal segment 1940 to rotate.

[0283] At least a portion of the fingertip insert 1996 can be made of a resilient material. At least a portion of the fingertip insert 1996 can be electrically conductive (e.g., can be coated with an electrically conductive material). This advantageously allows a user to interact with a touchscreen interface (e.g., of a phone, tablet, smartwatch, etc.) using the fingertip insert 1996. The fingertip insert 1996 can be matched to and / or configured to allow a user to grip an object. The fingertip insert 1996 can allow for grip and / or pitch precision. A distal surface of the fingertip insert 1996 can include a pattern (e.g., in the form of ridges or a raised surface). The ridges can be configured to create friction to help a user grip an object. A volume within the fingertip insert 1996 can allow for retrofitting the insert 1996 (e.g., with pressure, heat, vibration, touch sensors, etc.).

[0284] Various modifications to the implementations described in this disclosure can be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other implementations without departing from the spirit or scope of this disclosure. Thus, the disclosure is not intended to be limited to the implementations shown herein but is to be accorded the widest scope consistent with the claims, the principles and the novel features disclosed herein. The word "example" is used herein to mean "serving as an example, instance, or illustration." Any implementation described herein as "example" is not necessarily to be construed as preferred or advantageous over other implementations.

[0285] While several embodiments have been described, it should be apparent that many variations can be made which will still fall within the spirit and scope of the disclosure. Similarly, while operations have been depicted in a particular order, this should not be understood as requiring such order nor that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing can be advantageous. Moreover, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described program components and systems can generally be integrated in a single software product or packaged into multiple software products. Additionally, other implementations are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results.

[0286] Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring such order nor that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing can be advantageous. Moreover, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described program components and systems can generally be integrated in a single software product or packaged into multiple software products. Additionally, other implementations are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results.

[0287] Those skilled in the art will appreciate that, in general, the terms used herein are generally intended as "open" terms (e.g., the term "comprising" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). Those skilled in the art will further appreciate that if a specific number of an introduced claim limitation is intended, such intention would normally be explicitly recited in the claim and would not exist in the absence of such explicit recitation. For example, to assist in understanding, the following dependent claims can contain the use of the introductory phrases "at least one" and "one or more" to introduce claim limitations. However, the use of such phrases should not be interpreted as implying that any specific claim limitation introduced by the indefinite article "a" or "an" would limit any specific claim recited to contain only one such limited embodiment, even when the same claim includes the introductory phrase "one or more" or "at least one" along with the indefinite article, e.g., "a" or "an" (e.g., "a" or "an" should normally be interpreted as "at least one" or "one or more"); the same would apply to the use of the definite article for the limitation of introduced claims. Moreover, even where a specific number of a limitation of an introduced claim is explicitly recited, those skilled in the art will recognize that such limitation should normally be interpreted as at least the recited number (e.g., a simple recitation of "two limitations" without further modification would normally mean at least two limitations, or two or more limitations). Furthermore, where conventions similar to "at least one of A, B, and C, etc." are used, generally such structure is intended to be understood by those skilled in the art as meaning of that convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to the following systems: only A, only B, only C, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). Where conventions similar to "at least one of A, B, or C, etc." are used, generally such structure is intended to be understood by those skilled in the art as meaning of that convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to the following systems: only A, only B, only C, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). Those skilled in the art will further appreciate that any conjunctive words and / or phrases, whether presented in the specification, claims, or drawings, that in fact present two or more alternative terms, are to be interpreted to consider the possibility of including one term, either term, or both terms. For example, the phrase "A or B" would be interpreted to include the possibility of "A," or "B," or "A and B."

Claims

1. A prosthetic finger, comprising: The mounting element is configured to attach to the hand; The device comprises a proximal segment, a middle segment, and a distal segment, wherein the proximal segment is rotatably attached to the mounting member, and the middle segment is rotatably attached to the proximal segment and the distal segment, wherein the proximal segment has a drive side and a support side, the drive side being configured to be actuated to rotate the proximal segment, and the support side being configured to provide rotational resistance to the finger in response to a threshold lateral load applied to the finger; A link rotatably attached to the mounting and rotatably attached to the middle section, the link including a flexible portion at its distal end and configured to bend in response to a threshold rotational force applied to the finger; and An actuator, which is coupled to the mounting and configured to rotate the proximal segment via the drive side, wherein the actuator comprises a parallel motor and a gearbox mechanically connected by one or more transmission gears.

2. The prosthetic finger according to claim 1, wherein, The link also includes a proximal link and a distal link, and the distal link includes the flexible portion.

3. The prosthetic finger according to claim 2, wherein, The distal link is rotatably attached to the proximal link and the distal segment.

4. The prosthetic finger according to claim 2, wherein, The proximal link includes a turning section.

5. The prosthetic finger according to claim 1, wherein, The rotation of the proximal segment causes the proximal segment, the middle segment, and the distal segment to rotate simultaneously.

6. The prosthetic finger according to claim 1, wherein, The actuator also includes a tension spring and a worm gear, wherein the tension spring is configured to rotatably bias the worm gear in an angular direction.

7. The prosthetic finger of claim 1, further comprising a thrust bearing configured to provide the rotational resistance in response to the threshold lateral load applied to the finger.

8. The prosthetic finger of claim 1, further comprising an elastomeric fingertip insert configured to be coupled to the distal segment, wherein at least a portion of the insert is conductive.

9. A prosthetic finger, comprising: The mounting element is configured to attach to the hand; The device comprises a proximal segment, a mid-segment, and a distal segment, the proximal segment being rotatably attached to the mounting member, and the mid-segment being rotatably attached to the proximal and distal segments, wherein the proximal segment has a drive side and a support side, the drive side being configured to transmit actuation to the proximal segment, and the support side being configured to provide support to the finger in response to a threshold lateral load applied to the finger, wherein the support side includes a first opposing surface spaced apart from a second opposing surface by a gap therebetween, and wherein under a lateral load exceeding the threshold lateral load applied to the finger, the proximal segment is configured to laterally bend to close the gap, such that the first opposing surface and the second opposing surface contact each other and increase rotational friction of the finger; A connecting rod rotatably attached to a mounting member and rotatably attached to the middle section, the connecting rod including a flexible portion; and An actuator, which is coupled to the mounting and configured to rotate the proximal segment via the drive side, wherein the actuator comprises a parallel motor and a gearbox mechanically connected by one or more transmission gears.

10. The prosthetic finger according to claim 9, wherein, The link also includes a proximal link and a distal link, and the distal link includes the flexible portion.

11. The prosthetic finger according to claim 10, wherein, The distal link is rotatably attached to the proximal link and the distal segment.

12. The prosthetic finger as described in claim 9, wherein, The rotation of the proximal segment causes the proximal segment, the middle segment, and the distal segment to rotate simultaneously.

13. The prosthetic finger according to claim 9, wherein, The actuator also includes a tension spring and a worm gear, wherein the tension spring is configured to rotatably bias the worm gear in an angular direction.

14. The prosthetic finger of claim 9 further includes a thrust bearing configured to provide rotational motion while bearing axial force.

15. The prosthetic finger of claim 9, further comprising an elastomeric fingertip insert configured to be coupled to the distal segment, wherein at least a portion of the insert is conductive.

16. A prosthetic finger, comprising: The mounting element is configured to attach to the hand; The device comprises a proximal segment, a middle segment, and a distal segment, wherein the proximal segment is rotatably attached to the mounting member, and the middle segment is rotatably attached to the proximal segment and the distal segment, wherein the proximal segment has a drive side and a support side, the drive side being configured to be actuated to rotate the proximal segment, and the support side being configured to provide rotational resistance to the finger in response to a threshold lateral load applied to the finger; A link, rotatably attached to the mount and the middle section, the link including a flexible portion configured to bend in response to a threshold rotational force applied to the finger; as well as An actuator, which is coupled to the mounting and configured to rotate the proximal section via the drive side, wherein the actuator includes a motor extending parallel to the planetary gearbox, wherein the output shaft of the motor is mechanically connected to the planetary gearbox via a series of transmission gears located at a first end of the motor and the planetary gearbox and extending perpendicular to the motor and the planetary gearbox.

17. The prosthetic finger according to claim 16, wherein, The link also includes a proximal link and a distal link, and the distal link includes the flexible portion.

18. The prosthetic finger according to claim 17, wherein, The distal link is rotatably attached to the proximal link and the distal segment.

19. The prosthetic finger according to claim 16, wherein, The longitudinal axis of the motor extends parallel to the longitudinal axis of the gearbox.

20. The prosthetic finger as claimed in claim 16, wherein, The longitudinal axis of the motor extends perpendicular to the longitudinal axis of the transmission gearbox, which houses the series of transmission gears.

21. The prosthetic finger as described in claim 16, wherein, The rotation of the proximal segment causes the proximal segment, the middle segment, and the distal segment to rotate simultaneously.

22. The prosthetic finger according to claim 16, wherein, The actuator also includes a tension spring and a worm gear, wherein the tension spring is configured to rotatably bias the worm gear in an angular direction.

23. The prosthetic finger of claim 16, further comprising a thrust bearing configured to provide the rotational resistance in response to the threshold lateral load applied to the prosthetic finger.

24. The prosthetic finger of claim 16, further comprising an elastomeric fingertip insert configured to be coupled to the distal segment, wherein at least a portion of the insert is conductive.

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