Development of a two-fingered robot hand with capability of adjusting compliance.

Abstract

A multifingered hand system for robots with a capability of controlling joint compliance has been developed. In order to drive each finger joint, a pulley-cable system with DC motor was introduced. Usual pulley-cable driving systems have friction and low rigidity, which make high quality compliance control difficult. To compensate for these undesirable characteristics, a small specially designed strain sensor was installed near the joint and was used to construct torque sensory feedback. Through experiments using the individual joint, the effectiveness of the feedback was confirmed. The system developed was a two-fingred hand, each of which has three joints. To evaluate the system, the joint compliance was measured at each joint and the compliance ellipsoid was measured at the finger tip. From these measurements, it was found that the developed finger system provides stable and fine compliance controle ability.