Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-25T18:09:29.258Z Has data issue: false hasContentIssue false

Control of grasp stiffness using a multifingered robot hand with redundant joints

Published online by Cambridge University Press:  09 March 2009

H. R. Choi
Affiliation:
School of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), San 31 Hyoja Dong, Pohang 790–784 (Korea)
W. K. Chung
Affiliation:
School of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), San 31 Hyoja Dong, Pohang 790–784 (Korea)
Y. Youm
Affiliation:
School of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), San 31 Hyoja Dong, Pohang 790–784 (Korea)

Summary

This paper addresses a method of satisfactorily controlling the grasp of objects. Emphasis is placed on achieving the desired stiffness of a grasped object as accurately as possible, especially when the fingers have redundant joints. A model describing the relation between stiffness and force is derived. Based upon this model, a hierarchical control scheme of the grasp stiffness, called decentralized object stiffness control (DOSC) is proposed. DOSC is composed of a fingertip stiffness synthesis (FSS) algorithm and orthogonal stiffness decomposition control (OSDC). Employing the proposed FSS always achieves the desired grasp stiffness by solving the constrained least square problem. The computed fingertip stiffness is achieved by OSDC. It offers a feasible way of controlling the fingertip stiffness as well as maintaining the stability of the finger configuration by modulating the joint stiffness. The developed control method is implemented on a two-fingered planar robot hand one finger of which has a redundant joint. The effectiveness of the control method is confirmed experimentally.

Type
Articles
Copyright
Copyright © Cambridge University Press 1995

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Raibert, M.H. and Craig, J. J., “Hybrid Position/ForceControl of ManipulatorsTrans. ASME, Dynamic Systems, Measurements and Control 102, No. 6, 126133 (1981).CrossRefGoogle Scholar
2.Hogan, N., “Impedance Control: An Approach to Manipulation, Part 1, 2, 3Trans. ASME, Dynamic Systems, Measurement and Control 107,124 (1985).CrossRefGoogle Scholar
3.Salisbury, J.K. and Craig, J.J., “Articulated Hands: Force Control and Kinematic IssuesInt. J. of Robotics Research 1, No. 1, 417 (1982).CrossRefGoogle Scholar
4.Starr, G.P., “An Experimental Investigation of Object Stiffness Control Using a Multifingered HandRobotics and Autonomous Systems 10, 3342 (1992).CrossRefGoogle Scholar
5.Cutkosky, M.R. and Kao, I., “Computing and Controlling the Compliance of Robotic HandIEEE Trans, on Robotics and Automation 5, No. 2, 151165 (1989).CrossRefGoogle Scholar
6.Nguyen, V., “Constructing Stable GraspsInt. J. Robotics Research 8, No. 1, 2637 (1989).CrossRefGoogle Scholar
7.Kaneko, M., Imamura, N.YoloiN., K. N., K. and Tanie, K., “A Realization of Stable Grasp Based on Virtual Stiffness Model by Robot Fingers” Proc. IEEE Int. Workshop on Advanced Motion Control, Yokohama, Japan, (1990) pp. 156163.Google Scholar
8.Schneider, S.A. and Cannon, R.H. Jr., “Object Impedance Control for Cooperative Manipulation: Theory and Experimental ResultsIEEE Trans. Robotics and Automation 8, No. 3, 383394 (1992).CrossRefGoogle Scholar
9.Shimoga, K.B. and Goldenberg, A.A., “Constructing Multifingered Grasps to Achieve Admittance Center” Proc. IEEE Int. Conf. on Robotics and Automation, Nice, France (1992) pp. 22962301.Google Scholar
10.Maekawa, H., Kaneko, M., Yokoi, K., Tanie, K. and Imamura, N., “Grasp Control for a Multifingered Hand with Kinematic RedundancyJSME Int. J. Series III, 33, No. 4, 546552 (1990).Google Scholar
11.Cheng, F.T. and Orin, D.E., “Optimal Force Distribution Multiple-Chain Robotic SystemsIEEE Trans, on Syst. Man, and Cybern., 21, No. 1, 1324 (1991).CrossRefGoogle Scholar
12.Rao, C.R. and Mitra, S.K., Generalized Inverse of Matrices and its Applications (J. Wiley & Sons, New York, 1971).Google Scholar
13.Kim, J.O., Khosla, P. and Chung, W.K., “Static Modeling and Control of Redundant ManipulatorsRobotics & Computer-Integrated Manufacturing 9, No. 2, 145157 (1992).CrossRefGoogle Scholar
14.Hirose, S. and Ma, S., “Coupled Tendon-driven Multijoint Manipulator” Proc. IEEE Int. Conf. on Robotics and Automation, Sacramento, CA (1991) pp. 12681275.Google Scholar
15.Ready Systems Inc., Manual of VRTXvelocity, realtime OIS (1991).Google Scholar