End Point Position Control of Multi-Link Flexible Manipulators Using SDRE method

Authors

Jamil M. Renno, University of Nevada, Las VegasFollow
Woosoon Yim, University of Nevada, Las VegasFollow
Sahjendra N. Singh, University of Nevada, Las VegasFollow

Document Type

Conference Proceeding

Publication Date

11-13-2004

Publication Title

2004 ASME International Mechanical Engineering Congress and Exposition

Publisher

American Society of Mechanical Engineers

First page number:

21

Last page number:

28

Abstract

This paper treats end point regulation of multi-link light-weight flexible manipulators using the State Dependent Riccati Equation: SDRE method. It is well known that end point trajectory control using widely used feedback linearization techniques is not possible when the equilibrium state of the zero dynamics of the system is unstable or weakly stable. Furthermore, control saturation is a major problem in controlling nonlinear systems. In this paper, an optimal control problem is formulated for the derivation of control law with and without control constraints on the joint torques for a multi-link flexible manipulator and suboptimal control laws are designed using the SDRE method. For the purpose of control, pseudo joint angles and elastic modes of each link are regulated to their equilibrium values which correspond to the target end point. Weighting matrices in the quadratic performance index provide flexibility in shaping the pseudo angles and elastic modes trajectories. In the closed-loop system, the equilibrium state is asymptotically stable, and vibration is suppressed. Simulation results are presented for a two-link flexible manipulator, which show that in the closed-loop system, end point trajectory tracking is accomplished even with constraints on the control torque. Results also show that the transient characteristics of the pseudo angles and elastic modes can be easily shaped by the choice of the performance criterion.

Keywords

Control theory; Flexible manipulators; Manipulators (Mechanism); Nonlinear systems; Position control; Trajectories (Mechanics)

Disciplines

Controls and Control Theory | Mechanical Engineering

Language

English

Comments

Conference Held: Anaheim, California, USA, November 13 – 19, 2004

Permissions

Use Find in Your Library, contact the author, or interlibrary loan to garner a copy of the item. Publisher policy does not allow archiving the final published version. If a post-print (author's peer-reviewed manuscript) is allowed and available, or publisher policy changes, the item will be deposited.

Repository Citation

Renno, J. M., Yim, W., Singh, S. N. (2004). End Point Position Control of Multi-Link Flexible Manipulators Using SDRE method. 2004 ASME International Mechanical Engineering Congress and Exposition 21-28. American Society of Mechanical Engineers.