Generation of the swing motion pattern of a multi-link robot for the explosive increase of the kinetic energy of the end-link by exploiting dynamic coupling

Abstract

This paper describes how to exploit the dynamic coupling of a multi-link robot to improve the motion ability without depending on only actuator power. The focus is on swing motion (e.g., throwing or kicking motion) in this paper. The prime purpose of swing motion is to increase the kinetic energy of the end-link (e.g., hand or foot). This paper proposed a method to generate the swing motion pattern for the explosive increase of the kinetic energy of the end-link. In general, a multi-link robot has high-power actuators in the base side. The high-power actuators can produce a large amount of mechanical energy. The dynamic coupling can transfer mechanical energy between the links. Mathematical models were constructed to transfer mechanical energy from the base side toward the end side and convert potential energy into kinetic energy in this paper. The swing motion pattern for the explosive increase of the kinetic energy of the end-link was generated on the basis of the models. The results of the simulation experiments showed that the kinetic energy of the end-link increased explosively. The reason was that a large amount of energy produced by the actuators in the base side was transferred toward the end side. Furthermore, they showed that the motion pattern was similar to the trajectory optimized based on energetic cost.

Keywords

• dynamic coupling
• multi-link robot
• swing motion pattern
• kinetic chain
• energy transfer
• free vibration