Autonomous Navigation of a Humanoid Robot Over Unknown Rough Terrain

The present paper describes the integration of laser-based perception, footstep planning, and walking control of a humanoid robot for navigation over previously unknown rough terrain. A perception system that obtains the shape of the surrounding environment to an accuracy of a few centimeters is realized based on input obtained using a scanning laser range sensor. A footstep planner decides the sequence of stepping positions using the obtained terrain shape. A walking controller that can cope with a few centimeters error in terrain shape measurement is achieved by combining 40 ms cycle online walking pattern generation and a sensor feedback ground reaction force controller. An operation interface that was developed to send commands to the robot is also presented. A mixed-reality display is adopted in order to realize intuitive interfaces. The navigation system is implemented on the HRP-2, a full-size humanoid robot. The performance of the proposed system for navigation over unknown rough terrain is investigated through several experiments.