Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-26T06:20:22.670Z Has data issue: false hasContentIssue false
  • English
  • Français

Generalized predictive control of a robotic manipulator with hydraulic actuators‡

Published online by Cambridge University Press:  09 March 2009

A. Kotzev ,
D. B. Cherchas ,
P. D. Lawrence  and
N. Sepehri
A. Kotzev
Affiliation:
Department of Mechanical Engineering, University of British Columbia, Vancouver B.C. (Canada) V6T 1Z4.
D. B. Cherchas
Affiliation:
Department of Mechanical Engineering, University of British Columbia, Vancouver B.C. (Canada) V6T 1Z4.
P. D. Lawrence
Affiliation:
Department of Electrical Engineering, University of British Columbia, Vancouver B.C. (Canada) B6T 1Z4.
N. Sepehri
Affiliation:
Department of Electrical Engineering, University of British Columbia, Vancouver B.C. (Canada) B6T 1Z4.
Get access Rights & Permissions [Opens in a new window]

Summary

This paper presents some aspects of the behavior of hydraulically actuated heavy duty manipulators. This category of manipulators is used extensively in large resource based industries and any improvement in efficiency may result in major financial benefits. In this paper an adaptive control algorithm is used for a two rigid link manipulator driven by hydraulic actuators. The dynamic model of the manipulator is derived as well as the models of the hydraulic actuators including compliance, dead time and full dynamics of the servo valves. An adaptive control algorithm is considered since changes occur on-line in the system's parameters. The adaptive algorithm used is Generalized Predictive Control (GPC). The GPC uses a controlled autoregressive integrated moving average (CARIMA) type model and a cost function that minimizes a predicted future output error and future weighted control inputs to the plant, resulting in a sequence of future control increments. The procedure, in this work, does not separate the hydraulic actuator and the link dynamics into separate sub-systems, but controls them as one system. The changes in the system's parameters due to the hydraulics or the link dynamics can be estimated and the coefficients of the model adjusted without the necessity of identifying the exact cause of the changes.

It was found in this work that the variations of the GPC control horizon can lead to faster response during transients and significantly reduced overshoot in the nonlinear hydraulic actuation system. An on-line change of the maximum output horizon is also introduced.

This work shows the analysis and results of a two link manipulator with hydraulic actuators. It can be implemented on any hydraulically actuated manipulator with any number of links and actuators.

Numerical simulations are performed on a Vax 3200 computer and the results are presented.

Keywords

Robot controlHydraulic actuatorsAdaptive algorithmModel
Type
Article
Information
Robotica , Volume 10 , Issue 5 , September 1992 , pp. 447 - 459
Copyright
Copyright © Cambridge University Press 1992

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]Craig, J.J., Introduction to Robotics Mechanics and Control (Addison-Wesley Publishing Company Inc., Reading Massachusetts, 1986).Google Scholar
[2]Tomizuka, M., Horowitz, R., Anwar, G. and Jia, Y.L., “Implementation of adaptive techniques for motion control of robotic manipulators”, ASME. J. BE, 110, 63 (09, 1988).Google Scholar
[3]Merritt, H.E., Hydraulic Control Systems (John Wiley and Sons, Inc., New York, 1966).Google Scholar
[4]Vaha, P., “Application of parameter adaptive approach to servo control of a hydraulic manipulator”, Acta Polytechnica Scandinavica, Mathematics and Computer Science 51, 3–86 (1988).Google Scholar
[5]Sepehri, N., Dumont, G.A.M., Lawrence, P.D. and Sassani, F., “Cascade Control of Hydraulic Actuated Manipulators”, Robotica 8, part 3, 207–216 (1990).CrossRefGoogle Scholar
[6]Astrom, K.J. and Wittenmark, B., Adaptive Control (Addison-Wesley Publishing Company, Reading, Massachusetts, 1989).Google Scholar
[7]Astrom, K.J. and Wittenmark, B., “On self tuning regulators” Automatica, 9, 185–199 (1973).Google Scholar
[8]Astrom, K.J., Borrison, U., Ljung, L. and Wittenmark, B., “Theory and application of self tuning regulators”. Automatica 13, 457–476 (1977).CrossRefGoogle Scholar
[9]Landau, Y.D., Adaptive Control—the Model Reference Approach (Course of Theoretical Physics. Marcel Dekker Inc., 1979).Google Scholar
[10]Edgar, B., Stability of Adaptive Controller (Springer-Verlag, Berlin Heidelberg, New York, 1979).Google Scholar
[11]Clarke, D.W., Mohtadi, C. and Tuffs, P.S., “Generalized predictive control—Part I. The basic algorithm”. Automatica 23(2), 137–148 (1987).Google Scholar
[12]Clarke, D.W., Mohtadi, C. and Tuffs, P.S.”, Generalized predictive control—Part II. Extensions and interpretations”. Automatica 23(2), 149–160 (1987).CrossRefGoogle Scholar
[13]Latornell, D.J., “Force Control for Robotic Manipulators with Structurally Flexible Links.” PhD thesis (Dept. of Mechanical Engrg., University of British Columbia, 1992).Google Scholar
[14]Fu, K.S., Gonzolez, R.C. and Lee, C.S.G., Robotics: Control, Sensing, Vision, and Intelligence (McGraw-Hill Inc., New York, NY, 1987).Google Scholar
[15]Clarke, D.W and Gawthrop, P.J., “Self-tuning controller”, IEE Proceedings. Part D 122, 929–934 (1975).Google Scholar
[16]Walton, J., “The dynamic performance of an electro-hydraulic servovalve/motor system with transmission line effects, ASME J. Basic Engineering 190, 14–18 (03, 1987).Google Scholar
[17]Astrom, K.J. and Wittenmark, B., “Theory and application of self tuning regulators”. Automatica, 13, 457–476 (1977).CrossRefGoogle Scholar
[18]Demircioglu, H. and Gawthrop, P.J., “Continuous-time generalized predictive control (gpc)”, Automatica 27(1), 55–74 (1991).CrossRefGoogle Scholar
[19]Latornell, D.J. and Cherchas, D.B., “Force and motion control of a single flexible manipulator link”, Robotics and Computer Integrated Manufacturing 9, No. 2 (1992).Google Scholar