Control of flexible arms with friction in the joints

Author

Feliu, Vicente ; Rattan, Kuldip S. ; Brown, H. Benjamin, Jr.

Author_Institution

Dept. Ingenieria Electr., Electron. y de Control, Univ. Nacional de Educacion, Madrid, Spain

Volume

9

Issue

4

fYear

1993

fDate

8/1/1993 12:00:00 AM

Firstpage

467

Lastpage

475

Abstract

The control of flexible arms with friction in the joints is studied. A method to identify the dynamics of a flexible arm from its frequency response (which is strongly distorted by Coulomb´s friction) is proposed. A robust control scheme that minimizes the effects of this friction is presented. The scheme consists of two nested feedback loops: an inner loop to control the motor position and an outer loop to control the tip position. It is shown that a proper design of the inner loop eliminates the effects of friction while controlling the tip position and significantly simplifies the design of the outer loop. The proposed scheme is applied to a class of lightweight flexible arms, and the experiments show that the control scheme results in a simple controller. As a result, the computations are minimized and, thus, high sampling rates may be used

Keywords

dynamics; feedback; frequency response; friction; machine control; position control; robots; stability; dynamics; flexible arms; frequency response; friction; inner loop; joints; lightweight arms; motor position; nested feedback loops; outer loop; robust control; tip position; Arm; Control systems; DC motors; Feedback loop; Frequency response; Friction; Lighting control; Robotics and automation; Service robots; Torque;

fLanguage

English

Journal_Title

Robotics and Automation, IEEE Transactions on

Publisher

ieee

ISSN

1042-296X

Type

jour

DOI

10.1109/70.246058

Filename

246058