Model Reference Adaptive Control of Biped Robot Actuators for Mimicking Human Gait

Many robotics problems do not take the dynamics of the actuators into account in the formulation of the control solutions. The fallacy is in assuming that desired forces/torques can be instantaneously and accurately generated. In practice, actuator dynamics may be unknown and can have significant transient effect on the overall results. This paper presents a Model Reference Adaptive Controller (MRAC) for the actuators of a biped robot that mimics a human walking motion. The MRAC self-adjusts so that the actuators produce the desired torques in accordance with an inverse reference model. Lyapunov stability criterion is used to provide the MRAC structure, and a rate of convergence analysis is provided. The control scheme for the biped robot is simulated on a sagittal plane to verify the MRAC scheme for the actuators.