Abstract
This paper studies an effect of plastic deformation in the crashing process of a foot mechanism for humanoid robots. The previous mechanism that the authors developed had seriously large backlash and dry friction which caused plasticity against crash. The authors developed another mechanism which reduced backlash and have found that the shock absorption performance was rather degraded. They learned that the plastic deformation is more important than a variable-stiffness. By reducing dry friction with lubricant, deformation can be cancelled after unloading, so that the mechanical plastic deformation works for impact absorption and the following stable support.
