Control and online computation of stable movement for biped robots

Abstract

The presented algorithm enables a biped to perform a stable movement to a defined goal without using any precomputed trajectories. The algorithm merges the trajectory generation and the control along it, and can be used for global control, for local control along an existing trajectory, as well as for online computation of trajectories for stable movement. The algorithm is based on a decoupling of the non-linear model and changing the steering torques to account for both the overall stability of the biped and for achieving the goal. The algorithm is applied to the model of a biped moving in a sagittal plane. By specifying the goal as an arbitrary pelvis position the biped can perform movements such as sitting down or standing up. The performance of the algorithm is demonstrated in a simulation.