Dynamic analysis and control of biped locomotion in the double supporting phase

In biped locomotion, there are a double supporting phase with a kick and a single supporting phase concerned with making a forward step. This study is concerned with dynamic analysis and control in the double supporting phase. This phase is a closed-loop link system (constraint dynamic system) in which the dynamic states (floor reaction, joint torque) are restricted because the feet are not fixed to the floor. Therefore, it is preferable to use an analytical method by which the dynamic states would become clear. In this respect, the paper first refers to an analytical method using D'Alembert's principle, in which static forces are derived from static equilibrium equations for each link. Then, based on the analytical result, a control experiment is carried out and the usefulness of this method is shown.