Simulation of human gait and associated muscle activation strategies using sliding-mode control techniques

A sliding-mode controller, developed to drive a two-dimensional, 10-segment human locomotor system model to track kinematic gait samples, is described. Motion tracking by the controller is performed to an accuracy typically within one standard deviation of the mean for the 10 data samples tested, with the driving moments typically within two standard deviations of the mean calculated for the sampled gait trajectories. The sliding-mode approach also generates antagonistic muscle activity at periods when joint angle is particularly sensitive to joint moment, producing results comparable to sampled electromyogram readings.