Advertisement

A Unified Passivity Based Control Framework for Position, Torque and Impedance Control of Flexible Joint Robots

  • Alin Albu-Schäffer
  • Christian Ott
  • Gerd Hirzinger
Part of the Springer Tracts in Advanced Robotics book series (STAR, volume 28)

Abstract

In this paper we describe a general passivity based framework for the control of flexible joint robots. Herein the recent DLR results on torque-, position-, as well as impedance control of flexible joint robots are summarized, and the relations between the individual contributions are highlighted. It is shown that an inner torque feedback loop can be incorporated into a passivity based analysis by interpreting torque feedback in terms of shaping of the motor inertia. This result, which implicitly was already included in our earlier works on torque- and position control, can also be seized for the design of impedance controllers. For impedance control, furthermore, potential shaping is of special interest. It is shown how, based only on the motor angles, a potential function can be designed which simultaneously incorporates gravity compensation and a desired Cartesian stiffness relation for the link angles.

Keywords

Joint Torque Impedance Control Motor Position Gravity Compensation Impedance Controller 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    A. Albu-Schäffer. Regelung von Robotern mit elastischen Gelenken am Beispiel der DLR-Leichtbauarme. PhD thesis, Technical University Munich, april 2002.Google Scholar
  2. 2.
    A. Albu-Schäffer and G. Hirzinger. A globally stable state-feedback controller for flexible joint robots. Journal of Advanced Robotics, Special Issue: Selected Papers from IROS 2000, 15(8):799–814, 2001.Google Scholar
  3. 3.
    A. Albu-Schäffer and G. Hirzinger. Cartesian impedance control techniques for torque controlled light-weight robots. IEEE International Conference of Robotics and Automation, pages 657–663, 2002.Google Scholar
  4. 4.
    A. Albu-Schäffer, C. Ott, and G. Hirzinger. Passivity based cartesian impedance control for flexible joint manipulators. Proc. 6-th IFAC-Symposium on Nonlinear Control Systems, Stuttgart, 2:111, 2004.Google Scholar
  5. 5.
    A. Albu-Schäffer, C. Ott, and G. Hirzinger. A passivity based cartesian impedance controller for flexible joint robots-part ii:full state feedback, impedance design and experiments. ICRA, pages pp. 2666–2673, 2004.Google Scholar
  6. 6.
    A. Albu-Schäffer, C. Ott, and G. Hirzinger. Constructive energy shaping based impedance control for a class of underactuated euler-lagrange systems. ICRA, pages 1399–1405, 2005.Google Scholar
  7. 7.
    A. Bicchi, G. Toniettiand M. Bavaro, and M. Piccigallo. Variable stiffness actuators for fast and safe motion control. 11th International Symposium of Robotics Research (ISRR), oct. 2003.Google Scholar
  8. 8.
    B. Brogliato, R. Ortega, and R. Lozano. Global tracking controllers for flexible-joint manipulators: a comparative study. Automatica, 31(7):941–956, 1995.zbMATHCrossRefMathSciNetGoogle Scholar
  9. 9.
    S. Chen and I. Kao. Simulation of conservative congruence transformation conservative properties in the joint and cartesian spaces. IEEE International Conference of Robotics and Automation, pages 1283–1288, 2000.Google Scholar
  10. 10.
    A. DeLuca. Feedforward/feedback laws for the control of flexible robots. IEEE International Conference of Robotics and Automation, pages 233–240, 2000.Google Scholar
  11. 11.
    A. DeLuca and P. Lucibello. A general algorithm for dynamic feedback linearization of robots with elastic joints. IEEE International Conference of Robotics and Automation, pages 504–510, 1998.Google Scholar
  12. 12.
    G. Hirzinger, A. Albu-Schäffer, M. Hähnle, I. Schaefer, and N. Sporer. On a new generation of torque controlled light-weight robots. IEEE International Conference of Robotics and Automation, pages 3356–3363, 2001.Google Scholar
  13. 13.
    N. Hogan. Impedance control: An approach to manipulation, part I-theory, part II-implementation, part III-applications. Journ. of Dyn. Systems, Measurement and Control, 107:1–24, 1985.zbMATHCrossRefGoogle Scholar
  14. 14.
    T. Lin and A.A. Goldenberg. Robust adaptive control of flexible joint robots with joint torque feedback. IEEE International Conference of Robotics and Automation, RA-3(4):1229–1234, 1995.Google Scholar
  15. 15.
    C. Ott, A. Albu-Schäffer, and G. Hirzinger. Comparison of adaptive and non-adaptive tracking control laws for a flexible joint manipulator. IROS, 2002.Google Scholar
  16. 16.
    C. Ott, A. Albu-Schäffer, and G. Hirzinger. A passivity based cartesian impedance controller for flexible joint robots-part i:torque feedback and gravity compensation. ICRA, pages pp. 2659–2665, 2004.Google Scholar
  17. 17.
    M. Spong. Modeling and control of elastic joint robots. IEEE Journal of Robotics and Automation, RA-3(4):291–300, 1987.MathSciNetCrossRefGoogle Scholar
  18. 18.
    S. Sugano. Human-robot symbiosis. Workshop on Human-Robot Interaction, ICRA, 2002.Google Scholar
  19. 19.
    P. Tomei. A simple PD controller for robots with elastic joints. IEEE Transactions on Automatic Control, 36(10):1208–1213, 1991.CrossRefMathSciNetGoogle Scholar
  20. 20.
    M. Vidyasagar. Nonlinear Systems Analysis. Prentice-Hall, 1978.Google Scholar
  21. 21.
    M. Zinn, O. Khatib, B. Roth, and J.K. Salisbury. A new actuation approach for human friendly robot design. Int. Symp. on Experimental Robotics, Ischia, 2002.Google Scholar
  22. 22.
    L. Zollo, B. Siciliano, A. De Luca, E. Guglielmelli, and P. Dario. Compliance control for a robot with elastic joints. Proceedings of the 11th International Conference on Advanced Robotics, Coimbra, Portugal, pages pp. 1411–1416, june 2003.Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Alin Albu-Schäffer
    • 1
  • Christian Ott
    • 1
  • Gerd Hirzinger
    • 1
  1. 1.Institute of Robotics and MechatronicsGerman Aerospace Center (DLR)Germany

Personalised recommendations