Output space tracking control for above-knee prosthesis

Abstract

The control of a knee joint in an active above-knee prosthesis has been designed using the Lyapunov tracking method. A simulation of locomotion was done to prove that the tracking control in output space is a valuable real time control method for artificial legs. The data used for simulation was collected in able-bodied subjects while they walked on a powered treadmill. Human volunteers were braced with an ankle splint (limiting dorsi- and plantar flexion) and with a knee cage (limiting knee movements to the lateral plane). We studied the achieved tracking of the prescribed knee motion, deviations of the thigh movement from the prescribed trajectory, maximal angular deviations from the desired trajectory and the power consumption as functions of a limited maximal knee torque and a damping constant in the knee actuator. We found that the use of output tracking method is suitable for the design of appropriate hardware of an above-knee prosthesis and for real-time control.

Feedback error learning neural network for trans-femoral prosthesis

“…off-line simulation of the trans-femoral prosthesis. Liapunov method in output space for control of the artificial leg was described in detail in our earlier studies [15]. The algorithms listed are not applicable for real time control, but only for biomechanical analysis and designing of prosthetic components.…”

Design and control of an active artificial knee joint

“…The third requirement is that an undesirable pressure at the socket-stump interface and the gait abnormalities due to painful contact must be prevented. In addition, the AKP must contain all its parts such as actuator, energy source, controller and sensors [1].…”

“…Several studies have been performed and presented in the literature to design better prosthetic devices in the field of externally powered above knee prosthesis (AKP). The Belgrade leg and the Waseda leg are two of them [1][2][3][4][5][6].…”

Research on the Nonlinear Computer Torque control of the MR Damper Based Above-knee Prosthesis

“…Nevertheless, the MRAKP is a strongnonlinearity system in which a small disturbance may cause huge oscillation. So the conventional control methods with fixed parameters are bad at robustness for the MRAKPs in practice [9][10][11][12][13].…”