Gain-Scheduling H_∞ Vibration Control of SCARA Type Robot Manipulators

Abstract

This paper is concerned with the application of gain-scheduling H_∞ technique to the vibration control of SCARA type robot manipulators. The dynamics of multi-link robot manipulators, such as the SCARA type robot manipulators, are of highly nonlinear time-varying property, and this fact makes it difficult for a single linear time-invariant controller to achieve the desired performance. The gain-scheduling H_∞ technique is an extension of standard H_∞ synthesis technique to the case that a plant depends affinely on a time-varying parameter vector δ(t). The vibration controller designed via this technique is automatically gain-scheduled according to the position of the links of the manipulators and makes the dynamics of the closed-loop system unchanged along the input trajectory. The effectiveness of the proposed controller is demonstrated by simulation.