Analysis of the stability control of motors used in biomechanical prostheses

Abstract

We present an alternative analysis for the energy optimization and system stability in servomotors that drive biomechanical prostheses using a LQR (Linear Quadratic Regulator) controller. The model is designed in the state space, and we use the Lyapunov Function as a parameter of the system stability. From the observation of the dynamical response and transition of the system variables, angular position, angular velocity and armature current of the model, we found that the use of LQR with its respective controlling action generates in the system a convergence to an equilibrium point xe in less than 3 seconds, ensuring stability with a shorter trajectory.