A fastening device for fastening a prosthesis shaft to a prosthetic knee joint that has a proximal top part and a distal bottom part, which are mounted on one another to pivot about a prosthetic knee joint axis. The fastening device has a distal bracket for attachment to the bottom part or to a lower-leg tube. At least one strut extends in the proximal direction from the holder beyond the prosthetic knee joint axis and on the strut a receptacle is arranged proximally to the prosthetic knee joint axis for pivotally mounting the prosthesis shaft about a shaft pivot access. At least one force transfer element is fastened offset to the to the shaft pivot access at a proximal bearing point to transfer a pivoting movement of the prosthesis shaft. The force transfer element is coupled to the top part at a distal bearing point in such a way that a pivoting movement of the prosthesis shaft about the shaft pivot axis causes a pivoting movement of the top part about the prosthetic knee joint axis.

A knee joint structure includes a knee joint head portion, a knee-joint body portion, and at least one curved plate. The knee joint head portion includes a position-returning device made up of a piston, an elastic body, and an adjustment cap and a transmission axle. The transmission axle includes a push-bar axle, which is pivotally coupled to a push bar operable to drive and move the piston. The knee-joint body portion includes a connection rod pivotally connected to the knee joint head portion. The curved plate connects the transmission axle and the knee joint body portion.

Exemplary embodiments herein relate to a unique 4-bar linkage transmission provided between two adjacent links of a powered augmentation device that provides a varying mechanical advantage. Due to the kinematics of the linkage, the mechanical advantage between the actuator and the augmented joint varies with the position of the linkage. Thus, a high mechanical advantage can be provided in positions at which relatively high joint torque is required, and low mechanical advantage in positions at which relatively high joint speed is required. Consequently, the speed-torque (or velocity-force) operating area of the actuator can be consolidated by mapping the widespread output regions onto a smaller input region. This allows the actuator to be optimized for a narrower range of usage.

A polycentric knee joint including an adjustment-free multi-stage prosthesis air cylinder. The air cylinder has an air cylinder body, a piston assembly slidably mounted on the air cylinder body, a first check valve mounted in the piston, and a multi-stage air pressure valve mounted inside a lower air way of the air cylinder body. The multi-stage air pressure valve automatically cushions movements of the piston assembly without being adjusted whenever a user of the prosthesis joint walks slowly or quickly, for improved comfort.

A passive prosthetic knee may include a top adapter that may connect an exemplary passive prosthetic knee to a thigh socket and a four-link structure mimicking a knee joint attached to an exemplary top adapter. A passive prosthetic knee may further include a stance spring, a swing spring, and a switching mechanism configured to selectively urge the stance spring and the swing spring to alternately get engaged with an exemplary four-link structure. A passive prosthetic knee may further include a bottom adapter that may be utilized for connecting an exemplary passive prosthetic knee to a lower leg prosthesis. An exemplary switching mechanism may be mounted between an exemplary four-link structure and an exemplary bottom adapter.

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.

The present disclosure provides for a device and method of control for an artificial prosthetic knee. A prosthetic knee according to the present disclosure relies on strictly passive means of providing support during weight bearing and supplements a resistive swing-phase mechanism with a small powered actuator. This actuator adds power to the knee, exclusively during swing phase, to improve swing-phase behavior. In particular, the knee still relies on the resistive swing-phase mechanism to provide nominal swing-phase knee motion, but supplements that motion as needed with the small powered actuator.

A polycentric knee joint including an adjustment-free multi-stage prosthesis air cylinder. The air cylinder has an air cylinder body, a piston assembly slidably mounted on the air cylinder body, a first check valve mounted in the piston, and a multi-stage air pressure valve mounted inside a lower air way of the air cylinder body. The multi-stage air pressure valve automatically cushions movements of the piston assembly without being adjusted whenever a user of the prosthesis joint walks slowly or quickly, for improved comfort.

A multi-articulated link knee joint includes: a knee unit in which an upper link unit rotates relative to a lower link unit by a multi-articulated link mechanism including a plurality of link units including the upper link unit and the lower link unit; a cylinder device for assisting the motion of the knee unit and moving in accordance with the rotation of the upper link unit; a position detector for detecting the distance from the lower link unit to the cylinder device; and an angle detector for obtaining the bending angle of the knee unit from the detected distance from the cylinder device.

A multi-articulated link knee joint includes: a knee unit in which an upper link unit rotates relative to a lower link unit by a multi-articulated link mechanism including a plurality of link units including the upper link unit and the lower link unit; a cylinder device for assisting the motion of the knee unit and moving in accordance with the rotation of the upper link unit; a position detector for detecting the distance from the lower link unit to the cylinder device; and an angle detector for obtaining the bending angle of the knee unit from the detected distance from the cylinder device.