In an artificial limb system having an actuator coupled to a joint for applying a torque characteristic thereto, a control bandwidth of a motor controller for a motor included in the actuator can be increased by augmenting a current feedback loop in the motor controller with a feed forward of estimated back electromotive force (emf) voltage associated with, the motor. Alternatively, the current loop is eliminated and replaced with a voltage loop related to joint torque. The voltage loop may also be augmented with the feed forward of estimated back emf, to improve the robustness of the motor controller.

A high torque active mechanism for an orthotic and/or prosthetic joint using a primary brake which can be provide by magnetorheological (MR) rotational damper incorporating and an additional friction brake mechanism driven by the braking force generated by the MR damper. This combination of MR damper and friction brake mechanism allows an increase in torque density while keeping the same level of motion control offered by the MR damper alone. The increased torque density achieved by this high torque active mechanism allows to minimize the size of the actuating system, i.e. its diameter and/or breath, while maximizing its braking torque capability. In this regard, the friction brake mechanism is advantageously positioned around the MR damper, such that the dimension of the package is minimized.

A prosthetic knee provides security and stability, particularly to low activity users, household and limited community ambulators, single and/or slow speed ambulators, and those with little voluntary control, while also balancing walking (dynamic) performance for low activity users. The prosthetic knee includes a housing, parallel anterior links, a posterior link, and a chassis. The geometry of the links and their relationship to one another allow for low voluntary control, shortening of mid-swing, which reduces stumbling risk, and geometric stability in stance. The anterior links are particularly oriented, sized and located to provide for stability. The anterior links both extend above the posterior link and substantially below the posterior link. The prosthetic knee includes a locking mechanism arranged to arrest movement of the posterior link. The knee including a locking mechanism connected to the housing and arranged to block rotation of the posterior link. The locking mechanism is a spring loaded latch including a pair of elongate springs extending downwardly from the latch to the housing and being connected to the housing below the upper pivot point of the posterior link and to a pin engaging the forward end of the latch.

A lower limb prosthesis system and a method of controlling the prosthesis system to replace a missing lower extremity of an individual and perform a gait cycle are disclosed. The prosthesis system has a controller, one or more sensors, a prosthetic foot, and a movable ankle joint member coupled to the prosthetic foot. The movable ankle joint member comprises a hydraulic damping system that provides the ankle joint member damping resistance. The controller varies the damping resistance by providing volumetric flow control to the hydraulic damping system based on sensor data. In one embodiment, the hydraulic damping system comprises a hydraulic piston cylinder assembly, hydraulic fluid, and a valve to regulate the fluid. In one embodiment, the controller alters the damping resistance by modulating the valve to vary the hydraulic fluid flow within the hydraulic piston cylinder assembly of the movable ankle joint member based on sensor data.

The adjustable prosthetic leg, which is connected between a thigh and an artificial foot, has a controller, a connecting mechanism, a hydraulic unit, and a shell. The connecting mechanism and the hydraulic unit are pivotally connected to the controller, and the shell is pivotally connected to the hydraulic unit. The connecting mechanism extends into a hydraulic cylinder of the hydraulic unit. The hydraulic cylinder is in communication with a reserve hydraulic cylinder and a brake hydraulic cylinder of the hydraulic unit. The prosthetic leg allows a user to climb up or go down the stairs and walk on uneven ground easily without falling down.

A variable gain impedance controller for use in a control system for controlling a motorized prosthetic or orthotic apparatus provided with a joint The controller comprises a sensor input for receiving a signal indicative of an interaction between the apparatus and the ground, a torque sensor input for receiving a signal indicative of the torque at the joint and a variable gain scheduler in communication with the sensor input so as to receive data therefrom thereby providing a variable torque gain. The variable gain impedance controller adjusts its control on the apparatus based on the variable torque gain and the indicated torque so as to a) increase the joint resistance to motion when the signal received from the sensor input indicates an interaction between the apparatus and the ground and b) decrease the joint resistance to motion when the signal received from the sensor input indicates an absence of interaction between the apparatus and the ground.

A buffer mechanism of an artificial limb is provided, including a joint connecting base, an artificial limb connecting base, a first connecting rod connected to a front side of the joint connecting base, a second connecting rod connected to a rear side of the artificial limb connecting base, and a buffer cylinder disposed between the first connecting rod and the second connecting rod and having a sleeve, a cylinder plug and a spring. The cylinder plug is detachably disposed at one end of the sleeve, the side surface of the first connecting rod facing the second connecting rod is disposed with a roller arm, an end of the roller arm is pivotally connected with a roller, and the roller arm contacts the end face of the cylinder plug by the roller. The present disclosure can reduce the wear rate of the cylinder plug and decrease the friction force.

A prosthetic leg knee joint includes a thigh connection part that is provided on the thigh side, a lower leg part that is provided rotatably around a knee shaft connected to the thigh connection part, a four-bar link mechanism that sets an instant center S whose relative position with respect to the thigh connection part is substantially constant regardless of the relative position between the thigh connection part and the lower leg part, and a braking unit that brakes the movement of the lower leg part in accordance with the relative position between the instance center S set by the four-bar link mechanism and the lower leg part.

The invention relates to a method for operating an orthopedic device which supports or replaces a first body part of a wearer and has at least one controllable actuator, wherein the method includes a) determining a chronological profile of at least one parameter, which allows for a conclusion to be made regarding a movement status of the wearer, from measurement values of at least one sensor; b) detecting the movement status from the at least one determined chronological profile; and c) controlling the at least one controllable actuator depending on the identified movement status, wherein at least the chronological profile of at least one parameter of a second body part of the wearer is also used to identify the movement status.

A method for controlling an artificial orthotic or prosthetic knee joint, on which a lower-leg component is arranged and with which a resistance device is associated, the bending resistance (R) of which resistance device is changed in dependence on sensor data that are determined by means of at least one sensor during the use of the orthotic or prosthetic knee joint, wherein a linear acceleration (a.sub.F) of the lower-leg component is determined, the determined linear acceleration (a.sub.F) is compared with at least one threshold value, and, if a threshold value of the linear acceleration (a.sub.F) of the lower-leg component is reached, the bending resistance (R) is changed.