Object Stepping-on/down Feasibility of Humanoid Robots

One motive for people to develop humanoid robots lies in their high mobility, like that of human being, which may be manifested by going upstairs/downstairs and negotiating obstacles by stepping-on/down or stepping-over. Due to the kinematics of the robot and the size of the objects, however, not all objects can be stepped on/down by the robot. In this paper, we address the possibility for a robot to step on/down a given object, considering the robot kinematics and the object size. We use a technique of global optimization under constraints to obtain the maximum height of the object that the robot can step on/down, keeping the balance and avoiding any collision between the robot legs and the object. This analysis provided us with necessary knowledge for the implementation of stair climbing and obstacle overcoming. It also provides an approach evaluating the mobility of humanoid robots