Stabilization of Biped Trunk in the Presense of Hip Motion Disturbance Using a Fuzzy-PID Controller

Abstract

Analysis of human gait is demonstrated that the movement of the hip is constrained in a sinusoidal path. In this paper, biped trunk oscillation in the presence of hip motion disturbance is approximated by a nonlinear inverted pendulum model. Then, the Biped trunk by torque hip control is stabilized using Fuzzy-PID control technique. In the torque control system, PID gains can be adjusted online by the fuzzy logic in accordance to the variation of inputs to stabilize the oscillation angle of the trunk. In order to investigate the performance of the proposed controller, the simulation results are compared with PID Controller tuned on Ziegler-Nichols method. In addition to, the robustness of proposed controllers is investigated by imposing disturbance in process. It can be seen that proposed control method has fast response, low overshoot and error, better tracking performance and strong robustness.