A prosthesis with controlled linear motion and methods for adapting the device to multiple amputation points are described. The device is designed to shorten during the swing phase to prevent striking the surface of the ground, and extend at the beginning and end of the swing to provide forward propulsion and begin to transfer bodyweight load from the opposing leg. The prosthesis includes an actuator to provide linear motion, a battery, sensors, and a controller.

A device includes a first member and a second member disposed in series along a longitudinal axis. The device also includes links coupling first joints of the first member to second joints of the second member. The first and second members and the links arranged to define a planar parallelogram linkage. The devices also include a resilient element disposed between the first member and the second member, the first member and the second member preloaded against the resilient element. The first member and the second member are preloaded to provide an arrangement of the first and the second joints in which a motion of the first joints with respect to the second joints is constrained to a direction substantially parallel to the longitudinal axis. The devices further include a sensor for generating a signal indicating a separation between the first member and the second member.

A lower limb modular prosthetic system that may be fabricated by a 3D printer capable of printing with composite fiber filament, nylon, or metal. The production process may include a 3D printer that is capable of routing fiber in specifically programmed patterns. The components of the prosthetic system may be designed for direct patient end-use, and may be energy returning in nature.

A mechanism has four connected links to mimic the motion of a knee joint. A lower link is oriented towards the vertical. A leverage ratio between flexion of the knee and relative angular displacement of certain links in the mechanism remains fairly steady over much of the range of motion of the mechanism. The mechanism may be used to drive an energy harvesting gearbox with steadier and more efficient energy harvesting at deep flexion, as well as with quieter operation.

Systems, methods, and apparatus provide an artificial knee. Such artificial knees may include a thigh link configured to move in unison with a thigh of the person, a shank link configured to be rotatably coupled to the thigh link, and a compression spring rotatably coupled to the thigh link at a first end and coupled to the shank link at a second end. The compression spring is configured to provide an extension torque between the thigh link and the shank link during a first range of motion of the thigh link and the shank link relative to each other. The compression spring is configured to provide a flexion torque between the thigh link and the shank link during a second range of motion of the thigh link and the shank link relative to each other.

A prosthetic knee joint with buffering and braking effects has an upper connecting base, a linking assembly, a braking assembly, and a lower connecting base. The upper connecting base has two extending arms and an accommodating recess. The linking assembly has two linking arms respectively and pivotally connected to the upper connecting base. The braking assembly has a braking arm protruding into the accommodating recess of the upper connecting base and pivotally connected to the two extending arms. The lower connecting base is connected to the linking assembly and the braking assembly. The upper connecting base, the linking assembly, the braking assembly and the lower connecting base form a four-bar linkage. A cushion between an abutting element and a main body provides a buffering effect during walking. Thus, the prosthetic knee joint has simplified structure and reduced cost and is convenient in assembly and use.

Some embodiments are directed to a lower limb articulation for bipedal locomotion, which includes a first element a second element and articulation devices for articulating the first and second elements relative to one another, the articulation devices including an articulation mechanism including first and second linking devices mounted in series, as well as devices for guiding and locking in position one of the first and second elements relative to the other one of the first and second elements when the lower limb comes to rest on a surface, the devices for locking in position including a potential trough.

The present disclosure describes transmission systems for use in artificial joints of assistive devices, such as assistive prostheses, orthoses, and powered exoskeletons. A variable transmission is configured to automatically or manually adapt the torque profile to the demand of different locomotion tasks, such as a relatively high torque and low speed profile for a task such as standing up or ascending stairs, or a relatively low torque and high speed profile for a task such as walking.

A technology for a prosthetic above-knee device is provided. A socket may be used to attach the device to a residual limb, and may have a rigid body coupled to the socket. The device may include a first link with a first link end coupled through the rigid body to the socket and a second link end coupled to the rigid body. The second link of the device may have a third link end attached to the rigid body, and a fourth link end coupled to a housing. The device may include a hydraulic cylinder with a piston and a hydraulic cylinder link coupled between the rigid body and the piston of the hydraulic cylinder. The stability adjustment nut may adjust a travel distance of the hydraulic cylinder link with respect to the hydraulic cylinder to provide an adjustment of an instant center for stability modification.

A prosthetic knee unit useful with a prosthetic leg. The prosthetic knee unit includes a linkage assembly, at least one motor module, and a controller. The linkage assembly includes a base, a driven shaft at least one link, and an output body. The motor module is operably connected to the driven shaft. The controller is programmed to prompt operation of the at least one motor module. Operation of the at least one motor module, as prompted by the controller, articulates the output body relative to the base via pivoting movement of the at least one link. In some embodiments, the prosthetic knee unit further includes at least one sensor, such as an IMU worn by the user. With these and related embodiments, the controller is programmed to receive sensed information from the sensor and to control operation of the at least one motor module based upon the sensed information.