Locomotion planning and implementation of humanoid robot Robo-Eectus Senior (RESr-1)

This paper presents design, control and implementation of the humanoid robot platform Robo-Erectus Senior (RESr-1). It is a full-size humanoid robot using self-contained modular component to perform cooperative works in general humanoid environment and robotic soccer (RoboCup) in particular. Mechatronic drives has cubic or double design with multiple connecting sockets in different orientations. Thereby, actuators, passive joints, rigid links can be rapidly assembled with various configurations having different kinematics and dynamic characteristics. In RESr-1, serial connected legs are parallel connected and controlled with individual controller. Based on the hierarchical control concept, low level trajectory are generated by decomposing locomotion into key poses as observed in humanoid locomotion. These poses are connected by sine, cosh and third-order interpolation functions. Thereby, walking pattern trajectories can satisfy continuity, smoothness with simple mathematical form. Simple locomotion planning methods for biped walking, turning and kicking are described. The proposed method provides a set of standard parameters for further optimization and learning with feedback information. It has been tested on RESr-1, which gave a outstanding exhibition in the Humanoid League of RoboCup2007. As shown in the experimental result, gaits are stable with various parameter value of stride length, pace time and double support phase ratio.