Budget Amount *help |
¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1996: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1995: ¥1,900,000 (Direct Cost: ¥1,900,000)
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Research Abstract |
Cooperation of multiple robots well be one of the most significant techniques for future robots. It can improve various performances of robotic systems, such as payload capacity, grasping function, and so on. When multiple robots grasp single object at the same time, geometrical constraints by closed loop structures are imposed on each robot. Thus compliance is needed for each robot to avoid excessive inner forces caused by the mutual positioning errors of robots. Installation of mechanical compliance, such as springs or free joints among robots is one of the most simple and effective solutions to avoid excessive inner forces for cooperation systems with PID position controllers. Moreover, the stability problem will not be so critical for slow motion control. In this research, a cooperative control system between two industrial robots was developed using prototype free joint mechanisms. First, the necessary kinematic conditions of installed free joint mechanisms for not only avoiding excessive inner forces but also holding grasped object rigidly against external forces are shown. Second, the kinematic characteristics and statics are analyzed and kinematics is formulated. After explaining the necessity of installing redundant free joints into cooperative systems, the developed mechanism with four free joints and electro-magnetic brakes is described. As the cooperative system with free joint mechanisms has two kinds of redundancy, a way to exploit the redundancy is proposed. Some fundamental experiments were done and the effectiveness of the proposed system was verified.
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