Coordination Control in Artificial Fingers
Toshio Fukuda*, H. Hosokai**, and Ken Shimonaka***
*Dept. of Mechanical Engineering, School of Engineering, Nagoya University 1 Furocho, Chikusa-ku, Nagoya 464, Japan
**Dept. of Mechanical Engineering Science, University of Tokyo
***Digital Switching System Enhancement Project, Software Engineering Center, Nippon Telegraph and Telephone Corp., NTT Shinagawa TWINS, 1-9-1 Konan, Minato-ku, Tokyo 108, Japan
This paper deals with the coordination force distribution at the finger joints of an articulated hand, under the assumption that the articulated hand with multiple degrees of freedom and a multiple articulated joint structure grasps some objects. In this study, four algorithms for this force distribution problem in grasping objects are derived from the static equilibrium conditions. Furthermore, a method for changing contact and noncontact fingers in grasping is derived and some simulations are shown, where changing fingers implies that some non-contacting fingers begin to make contact with the object, while the other contacting fingers cease to contact it, keeping the stable grasping condition of the hand as a whole. Finally, based on the proposed five control algorithms, a control flow of stable grasping methods for the force distribution at each joint is made for an overall control of the finger system by determining grasping forces to changing grasping fingers.