Detaching and Grasping Strategy Inspired by Human Behavior
Through grasp experiments by human achieving an enveloping grasp for a small cylindrical object placed on a table, we found an interesting grasping motion, where a human changes the finger posture from upright to curved ones after each finger makes contact with the object. During this motion, the object is automatically lifted up through either rolling or sliding motion between the fingertip and the object. A series of this motion is called as Detaching Assist Motion (DAM). An advantage of DAM is that most of grasping motions can be done on the table instead of in the air. Therefore, we can avoid the worst scenario where the object falls down to the table. We first discuss the basic mechanism of DAM by human experiments. We then apply the DAM to a grasping motion by a multi-fingered robot hand. We show that the DAM can be explained by using Self-Posture Changing Motion. We also show some simulation and experimental results to confirm that a small object can be grasped easily by applying the DAM.
KeywordsContact Force Contact Point Angular Displacement Link System Friction Boundary
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- S. Shimizu, M. Shimojo, S. Sato, Y. Seki, A. Takahashi, Y. Inukai and M. Yoshioka: “The Relation between Human Grip Types and Force Distribution Pattern in Grasping,” Proc. of the IEEE Int. Workshop on Robot and Human Communication (ROMAN’96), pp. 286–291, 1996.Google Scholar
- M. Kaneko, Y. Tanaka and T. Tsuji: “Scale-dependent Grasp,” Proc. of the IEEE Int. Conf. on Robotics and Automation, pp. 2131–2136, 1996.Google Scholar
- T. Shirai, M. Kaneko, K. Harada and T. Tsuji: “Scale-Dependent Grasps,” Proc. of the hit. Conf. on Advanced Mechatronics, pp. 197–202, 1998.Google Scholar
- A. Bicchi: “Analysis and Control of Power Grasping,” Proc. of IEEEIRSJ Int. Workshop on Intelligent Robots and Systems IROS’91, pp. 691–697, 1991.Google Scholar
- Y. Zhang, F. Gao and W.A. Gruver: “Determination of Contact Forces in Grasping,” Proc. of the IEEE Int. Conf. on Intelligent Robots and Systems, pp. 1038–1043, 1996.Google Scholar
- T. Ornate and K. Nagata: “Rigid Body Analysis of the Indeterminate Grasp Force in Power Grasps,” Proc. of the IEEE hit. Conf. on Robotics and Automation, pp. 1787–1794, 1996.Google Scholar
- M. Kaneko and K. Honkawa: “Contact Point and Force Sensing for Inner Link Based Grasps,” Proc. of the IEEE hit. Conf. on Robotics and Automation, pp. 2809–2814, 1994.Google Scholar