Standing balance control using a trajectory library

— This paper presents a standing balance controller. We employ a library of optimal trajectories and the neighboring optimal control method to generate local approximations to the optimal control. We take advantage of a parametric nonlinear optimization method, SNOPT, to generate initial trajectories and then use Differential Dynamic Programming (DDP) to further refine them and get their neighboring optimal control. A library generation method is proposed, which keeps the trajectory library to a reasonable size. We compare the proposed controller with an optimal controller and an LQR based gain scheduling controller using the same optimization criterion. Simulation results demonstrate the performance of the proposed method.

• Type: Conference
• Year: 2009
• Where: IROS
• Authors: Chenggang Liu, Christopher G. Atkeson
• Keywords: IROS 2009, Neighboring Optimal Control, Optimal Control Method, Optimal Trajectories, Robotics