Biologically-inspired control of a humanoid robot with nonlinear actuators

A humanoid robot with antagonist pairs of McKibben pneumatic artificial muscles was controlled using a biologically-inspired control paradigm. The paradigm used tonic-plus-phasic activation patterns to control the reaching movements of the robot's arm in the sagittal plane. The biologically-inspired control paradigm combined feedforward open-loop tonic activation patterns and tri-phasic activation patterns that were modeled after human EMG tonic-plus-phasic activation patterns. Proprioceptive feedback was employed to correct for time-varying system parameters and load changes. The paradigm was tested for the effects of reaching speed, reaching direction, and load size.; The tonic-plus-phasic control paradigm was capable of producing human-like movements where the robot's hand moved with a bell-shaped Cartesian velocity. When the robot was presented with unexpected load changes, the proprioceptive feedback controller activated the artificial muscles with an activation pattern that was similar to the muscle activation patterns in humans presented with similar load changes.