World Academy of Science, Engineering and Technology
Published June 5, 2015 | Version 10001576
Journal article Open

Implicit Force Control of a Position Controlled Robot – A Comparison with Explicit Algorithms

Authors/Creators

Description

This paper investigates simple implicit force control algorithms realizable with industrial robots. A lot of approaches already published are difficult to implement in commercial robot controllers, because the access to the robot joint torques is necessary or the complete dynamic model of the manipulator is used. In the past we already deal with explicit force control of a position controlled robot. Well known schemes of implicit force control are stiffness control, damping control and impedance control. Using such algorithms the contact force cannot be set directly. It is further the result of controller impedance, environment impedance and the commanded robot motion/position. The relationships of these properties are worked out in this paper in detail for the chosen implicit approaches. They have been adapted to be implementable on a position controlled robot. The behaviors of stiffness control and damping control are verified by practical experiments. For this purpose a suitable test bed was configured. Using the full mechanical impedance within the controller structure will not be practical in the case when the robot is in physical contact with the environment. This fact will be verified by simulation.

Files

10001576.pdf

Files (228.8 kB)

Name Size Download all
md5:e08e418bc13456dd0dda9d795f5e5bcc
228.8 kB Preview Download

Additional details

References

  • G. Zeng and A. Hemami, "An overview of robot force control," Robotica, vol. 15, no. 5, pp. 473–482, 1997.
  • M. Vukobratovi´c and A. Tuneski, "Contact control concepts in manipulation robotics–an overview," IEEE Transactions on Industrial Electronics, vol. 41, no. 1, pp. 12–24, 1994.
  • R. Volpe and P. Khosla, "A theoretical and experimental investigation of explicit force control strategies for manipulators," IEEE Transactions on Automatic Control, vol. 38, no. 11, pp. 1634–1650, 1993.
  • J. De Schutter and H. Van Brussels, "Compliant robot motion I. A formalism for specifying compliant motion tasks," International Journal of Robotics Research, vol. 7, no. 4, pp. 3–17, 1988.
  • E. D´egoulange and P. Dauchez, "External force control of an industrial PUMA 560 robot," Journal of Robotic Systems, vol. 11, no. 6, pp. 523–540, 1994.
  • A.Winkler and J. Such´y, "Position feedback in force control of industrial manipulators – an experimental comparison with basic algorithms," in IEEE International Symposium on Robotic and Sensors Environments, 2012, pp. 31–36.
  • ——, "Force controlled contour following on unknown objects with an industrial robot," in IEEE International Symposium on Robotic and Sensors Environments, 2013, pp. 208–213.
  • ——, "Force controlled contour following by an industrial robot on unknown objects with tool orientation control," in Proc. of Joint Conference on Robotics – 45th International Symposium on Robotics and 8th German Conference on Robotics, 2014.
  • J. J. Craig, Introduction to Robotics Mechanics and Control. Pearson Prentice Hall, 2005. [10] T. A. Lasky and T. C. Hsia, "Force control of robotic manipulators," in Applied Control, S. G. S. G. Tzafesta, Ed. Marcel Decker, 1993, ch. 22, pp. 639–661. [11] A. A. Goldenberg, "Implementation of force and impedance control in robot manipulators," in Proc. of IEEE International Conference on Robotics and Automation, vol. 3, 1988, pp. 1626–1632. [12] C. Natale, B. Siciliano, and L. Villani, "Robust hybrid force/position control with experiments on an industrial robot," in Proc. of the IEEE/ASME International Conference on Advanced Intelligent Mechatronics, 1999, pp. 956–960. [13] N. Hogan, "Impedance control, an approach to manipulation: Part i, ii, iii," ASME Journal of Dynamic Systems, Measurement and Control, vol. 107, pp. 1–24, 1985. [14] J. K. Salisbury, "Active stiffness control of a manipulator in cartesian coordinates," in Proceedings of the IEEE International Conference on Decision and Control, vol. 19, 1980, pp. 95–100. [15] D. E. Whitney, "Historical perspective and state of the art in robot force control," International Journal of Robotics Research, vol. 6, no. 1, pp. 3–14, 1987. [16] ——, "Force feedback control of manipulator fine motions," Journal of Dynamic Systems, Measurement and Control, vol. 99, no. 2, pp. 91–97, 1977. [17] KUKA Roboter GmbH, KUKA.RobotSensorInterface (RSI) 2.1, 2007. [18] A. Winkler and J. Such´y, "An approach to compliant motion of an industrial manipulator," in Proc. of the 8th International IFAC Symposium on Robot Control, 2006. [19] ——, "Possibilities of force based interaction with robot manipulators," in Human-Robot-Interaction, N. Sarkar, Ed. I-Tech Education and Publishing, 2007, pp. 445–468. [20] N. Hogan and S. P. Buerger, "Impedance and interaction control," in Robotics and Automation Handbook, T. R. Kurfess, Ed. CRC Press, 2004, ch. 19.