### “Adaptive control of a manipulator when the mass of the load is unknown”

**Authors:**Olav Egeland,

**Affiliation:**NTNU, Department of Engineering Cybernetics

**Reference:**1988, Vol 9, No 2, pp. 59-68.

**Keywords:**Robotics, adaptive control, parameter estimation

**Abstract:**An adaptive controller for a robotic manipulator is presented. In the control system, the computed torque technique is used to linearize and decouple the dynamic model. The computed torque technique requires that the complete dynamic model is known. Normally, this model is known except perhaps for a few parameters, e.g. load inertia and centre of gravity and friction co-efficients. In this paper, the unknown parameters, which all represent physical quantities, are estimated using a recursive prediction error method. The most recent parameter estimate is then used in the computed torque technique. The control system is applied to the positioning part of an industrial robot in a simulation experiment where the unknown parameter is the mass of the load. The controller performed well, and the mass of the load can even be estimated when the manipulator is accelerating and there is a large control deviation.

PDF (835 Kb) DOI: 10.4173/mic.1988.2.1

**DOI forward links to this article:**

[1] P. Dutkiewicz, K.R. Kozlowski and W.S. Wroblewski (1993), doi:10.1109/ISIE.1993.268779 |

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**BibTeX:**

@article{MIC-1988-2-1,

title={{Adaptive control of a manipulator when the mass of the load is unknown}},

author={Egeland, Olav},

journal={Modeling, Identification and Control},

volume={9},

number={2},

pages={59--68},

year={1988},

doi={10.4173/mic.1988.2.1},

publisher={Norwegian Society of Automatic Control}

};