Experiments in Control of a Flexible-Link Robotic Manipulator With Unknown Payload Dynamics: An Adaptive Approach

Abstract

This article presents technology that extends the concept of end-point control of a flexible-link robot arm to handle payloads with unknown internal dynamics. The approach is based on merging high-performance control with an innovative identification algorithm in a self-tuning regulator framework. Payload dynamics are identified in real time using recently de veloped subspace fitting techniques. Sufficient excitation issues are addressed. End-point feedback controllers are formulated using frequency-weighted linear quadratic gaussian design methods.

Experimental results demonstrating precision control of a very flexible single-link robot arm with unknown dynamic payloads are presented.

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