Cascade Controller Design for Compliant Actuators

Abstract:

Article Preview

Compliant actuators are widely used in industrial robots due to the fact that the compliant elements have the capacity to absorb excessive collision force and guarantee the robot safety. Moreover, the compliant elements can be also employed as force/torque sensors in the control loops. Therefore, the research on the compliant actuators is of importance in the theory and application sides. Specifically, it is required that the robot systems should have a low stiffness when the subjected collision force is greater than the prescribed injury tolerance. But, in the normal status, the systems maintain the required capability. In this paper, the system stiffness of a compliant actuator is defined as a mechanical impedance (the ratio between output force and output shaft angle). A cascade controller is well designed by following the results on analyzing the characteristic of compliant actuator impedance stability and collision. At the end, simulation results show the effectiveness of the analytic results and designed controller.

Info:

Periodical:

Edited by:

Hong-Sen Yan, Jianbin Zhang, Guanglin Wang, Kuei-Yuan Chan, Yidu Zhang, Chunjie Wang and Hai Zhang

Pages:

23-28

Citation:

T. Qiao and S. S. Bi, "Cascade Controller Design for Compliant Actuators", Applied Mechanics and Materials, Vol. 163, pp. 23-28, 2012

Online since:

April 2012

Export:

Price:

$38.00

[1] D.W. ROBINSON: Design and Analysis of Series Elasticity in Closed-loop Actuator Force Control ( PhD Thesis, Department of Mechanical Engineering, Massachusetts Institute of Technology, 2000).

[2] M. M. WILLIAMSON: Series Elastic Actuators (MS Thesis, Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 1995).

[3] G. A. PRATT and M. M. WILLIAMSON: Series Elastic Actuators, IEEE International Conference on Intelligent Robots and Systems, 1995, vol. 1, pp.399-406.

[4] G. A. PRATT: Stiffness isn't everything. In Fourth International Symposium on Experimental Robotics, ISER 95, (Stanford, California, June 30-July 2. 1995).

[5] D. W. ROBINSON, J. E. PRATT, D. J. PALUSKA and G. A. PRATT: Series elastic actuator development for a biomimetic walking robot. In 1999 IEEE/ASME International Conference on Advanced Intelligent Mechatronics, (Atlanta, USA. September 19-23, 1999). pp: 561-568.

DOI: https://doi.org/10.1109/aim.1999.803231

[6] G. A. PRATT, P. WILLIAMSON, C. BOLTON and A. HOFMAN: Late Motor Processing in Low-Impedance Robots: Impedance Control of Series Elastic Actuators, Proc of American Control Conference (Boston, Massachusetts, June 30-July 2, 2004). pp: 3245-3251.

[7] R. VAN HAM, B. VANDERBORGHT, B. VERRELST, M. Van DAMME and D. LEFEBER: Maccepa: the mechanically adjustable compliance and controllable equilibrium position actuator used in the controlled passive walking biped veronica. The 15th International Symposium on Measurement and Control in Robotics, (2005).

DOI: https://doi.org/10.1109/robot.2006.1642029

[8] H. HERR, A. WILKENFELD and J. BLAYA. Patient-adaptive prosthetic and orthotic leg systems. The 12th Nordic Baltic Conference on Biomedical Engineering and Medical Physics, (Reykjavik, Iceland, June 2002). p.123–128.

[9] M. KIM, J. WEBER and S. CHA: A design of a modular force sensing robot arm for self-assembling robots in a system. Robotics and Applications (Honolulu, Hawaii USA, August 2006).

[10] H. VALLERY: Passive and Accurate Torque Control of Series Elastic Actuators. Intelligent Robots and Systems, IROS 2007 (San Diego, Oct. 29 2007-Nov. 2 2007). p.3534 – 3538.

DOI: https://doi.org/10.1109/iros.2007.4399172

[11] G. WYETH: Demonstrating the Safety and Performance of a velocity sourced series elastic actuators. IEEE International Conference on Robotics and Automation. (Pasadena, CA, USA, May19-23, 2008). pp: 3642-3647.

DOI: https://doi.org/10.1109/robot.2008.4543769

[12] R. GHORBANI: On Controllable Stiffness Bipedal Walking (PhD Thesis, Department of Mechanical and Manufacturing Engineering, The University of Manitoba, 2008).

[13] E. COLGATE and N. HOGAN: An analysis of Contact Instability in Terms of Passive Equivalents, IEEE International Conference on Robotics and Automation. 1989. pp.404-409.

DOI: https://doi.org/10.1109/robot.1989.100021

[14] N. HOGAN: On the Stability of Manipulators Performing Contact Tasks, IEEE Journal of Robotics and Automation, Vol. 4 (December 1988) No. 6, pp: 677-686.

DOI: https://doi.org/10.1109/56.9305