Simplified Adaptive Control for a 3-Axis Robot

Abstract

Typical schemes of adaptive control are model reference adaptive control and adaptive pole placement control, but these are difficult to be applied to multi-input and multi-output (MIMO) systems because too much time is required to compute their complicated algorithms. Simplified adaptive control (SAC) has recently been proposed, whose algorithm is simple and is easily implemented to real systems.
This paper examines the applicability of SAC to a real system, that is, a 3-axis miniature robot whose dynamics varies with its payload and attitude. The robot is first regarded as a MIMO system to which the MIMO algorithm is implemented. The experimental results illustrate satisfactory performance, and verifies the applicability of the MIMO algorithm to a real system.
Since the interaction between three axes of the robot is known to be small, the single-input and single-output (SISO) algorithm of SAC is next implemented to individual axis, and the interaction is regarded to be absorbed to σ-modification term of the algorithm. The experimental results clarify that the SISO algorithm works almost the same as the MIMO one for this controlled system.