PID Controller Design for A Nonlinear Motion Control Based on Modelling the Dynamics of Adept 550 Robot

Abstract

The multiple link robot is a nonlinear system, in general whose characteristic polynomial is not unique, and whose control schemes depend on particular operating conditions. Among all kinds of controllers used for robot control, nearly 90% is PID controller in the industrial world, not only due to its simplicity and effectiveness, but also to its ability of coping with uncertainties and nonlinearities in the system. Since most of PID controllers are designed based on trial and error method for a black-box plant, for the precision motion control of a robot, it is more desirable to design the PID controller based on the mathematical model of the robot. This paper is dedicated to a PID controller design for a nonlinear motion control based on the mathematical modelling of the dynamics of Adept 550 Robot. The general relationships of the PID controller design on the robotic dynamics and the planned trajectory are derived. The analysis and simulations of its closed loop dynamics indicates its effectiveness in fast and accurate trajectory tracking. The results can be practically generalized to other cases of PID controller design for other robots in the industrial applications.

Article history: Received (21.05.2010); Revised (11.06.2010); Accepted (12.06.2010)