Preview tracking control of a flexible manipulator.

Abstract

Industrial robots are being used predominantry today for various purposes. By reducing the mass of the links of a robot, it is possible to improve its working speed and efficiency. Reduction in link mass, however, results in a lowering of stiffness, which causes problems such as lack of precision in positioning due to the elastic deformation caused by gravity, or elastic vibrations. In this paper, it is firstly shown that a smooth trajectory effectively reduces the elastic vibrations of a flexible manipulator. Then, a preview control system presented previously is extended to a multi-input/multi-output case and is applied to the flexible manipulator to show the high tracking precision. Finally, the two schemes are combined to achieve precise tracking and good damping at the same time.