A system and method for a compliant four-bar linkage mechanism for a robotic finger that includes: a monolithic bone structure comprised of a compliant joint region and an input link segment and a coupler link segment, wherein the input link segment and the coupler link segment are connected through the compliant joint; an output link; a ground structure; wherein the monolithic bone structure, output link, and ground structure are connected through a set of joints in a configuration of a compliant four-bar linkage mechanism which comprises: the output link on a first end and the coupler link segment connected through an output joint, the output link on a second end connected to a ground joint on the ground structure, and the monolithic bone structure connected to an input joint connected to the ground structure; and an actuation input coupled to the input joint.

A wrist device for a prosthetic limb is provided. The device (1) comprises a base member (3) connectable to the wearer of the device, and a support member (13) connectable to the limb. The support member (13) is pivotably connected to the base member (3) such that the support member can pivot about a pivot axis (A) relative to the base member. A damping mechanism is located between the base (3) member and the support member (5). The damping mechanism comprises a pinion (47) connected to the support member (5) and rotatable about the pivot axis (A) relative to the base member (3). A rack (35) is engaged with the pinion (47) such that rotational motion of the pinion causes a linear motion of the rack, and at least one biasing member (41) extends between the base member (3) and the rack. The biasing member (41) biases the rack (35) and support member (13) into a neutral position. A prosthetic limb incorporating the wrist device is also provided.

The joint device having a linking unit which links a first member and a second member in a manner allowing relative movement, and having an expansion/contraction device 12 which is connected across the first member 1 and the second member in a manner allowing power transmission and which can modify an angle formed by the first member and the second member around the linking member by expanding and contracting. The expansion/contraction device has a rotary unit which generates rotary power, and a conversion unit which is connected to the rotating unit in a manner allowing power transmission and converts the rotary power generated by the rotary unit into translational motion along a direction of expansion/contraction.

Features for prosthetic digits are described. The digits mimic natural fingers by having multiple articulating segments, for example three, that can rotate varying amounts. Rotatable and/or linearly expandable mechanical links are configured to provide the digit segments with multiple degrees of rotational freedom. The digit may have an actuator that outputs linear actuation to cause rotation of the digit segments. The digit may have an expandable proximal link to allow for variable relative rotational positions of the segments. Middle and/or distal digit segments may fully rotate independent of rotation of a proximal digit segment. The rotated digit may thus fully surround and grasp small or large objects, objects with irregular outer contours, etc.

Features for a prosthetic wrist and associated methods are described. The wrist couples with a prosthetic socket and a prosthetic hand. The wrist may rotate the hand. The wrist includes features to prevent or mitigate undesirable separation of the wrist from the socket. The wrist may have an expanding coupling, such as an expanding ring, to better secure the wrist with the socket. An actuator may cause the coupling to expand outward to prevent or mitigate undesirable separation of the wrist from the socket. Alternatively or in addition, the wrist may include torque control features to prevent undesirable or premature separation of the hand from the wrist, for example when using a “quick wrist disconnect” (QWD) apparatus. A torque control method may tailor or limit multiple torques to be applied by the wrist to the hand based on operational requirements and phases, such as anticipated torque loads and operational timing.

Gearwheel transmission comprising a first stage and a second stage, the second stage being a differential gearing comprising a planetary gear train system which is executed in a quasi duplicated form, wherein a first component is forming a torque resisting means, wherein a second component is interconnected or interacting with an output shaft, the overall transmission efficiency in the first stage being higher than in the second stage and/or the overall capacity for transmitting torque in the second stage being higher than in the first stage.

The invention relates to a hand prosthesis that can be adapted at the forearm or wrist. The prosthesis including a mechanical design with a smaller number of parts than the prior art, thus facilitating the assembly, maintenance and production thereof. Likewise, the prosthesis includes a plurality of motion transmission systems in a housing similar to the volume of a biological hand and provides sufficient grip strength to reincorporate the user into everyday activities. The invention includes an adult hand prosthesis, a child hand prosthesis and a wrist that allows the user to hold heavy loads while moving around.

Low-cost prosthetic apparatus, methods, kits, and systems with improved force transfer elements are disclosed. For example, the prosthetic apparatus may comprise: a plurality of first components manufactured from a first material to define 3D shapes with exterior surfaces resembling digits of a human hand; and a plurality of second components manufactured from a second material to define 2D shapes that are rotatably engageable with the 3D shapes to define force transfer elements operable to close the digits around an object responsive to a pull force applied to the force transfer elements, wherein the first material is different from the second material. Methods for manufacturing and assembling prosthetic apparatus also are disclosed along with related kits and systems.

A prosthetic arm apparatus comprising a plurality of segments that provide a user of the prosthetic arm apparatus with substantially the same movement capability and function as a human arm. The segments are connectable to one another and connectable to a harness mount that may be adorned by the user. Each segment of the plurality of segments provides a portion of the movement capability, enabling the plurality of connected segments connected to the harness mount to provide substantially the same movement capability as that lacking in the user.

A universal digit is formed to be attachable to the residual digit of a patient, and to have a lockable joint, so as to provide considerable utility and flexibility. The structure of the joint member allows the universal digit to be easily adjusted and manipulated so that the extension portion can be locked into multiple positions by easily manipulating adjustment buttons. The extension is rotatable about a first longitudinal axis, and is further rotatable about a transverse axis which is perpendicular to the longitudinal axis. The joint structure thus has three dimensions of movement and provides a significant number of diverse options for positioning of the extension. Unique locking mechanisms within the various structures allow the universal digit to be rigidly held in the desired position, thereby increasing the utility for a patient/user.