Development of a multivariable test facility for the evaluation of iterative learning controllers

This paper describes the development of a multivariable input, multivariable output (MIMO) experimental test facility, which will be used to evaluate, benchmark and compare advanced control strategies. The MIMO system incorporates two differential gears connected back-to-back, together with a number of spring-mass-damper modules. The system can be driven by two AC induction motors with inverter drives, and also a DC brushed motor and a four-quadrant drive. It incorporates two encoders, and a torque tube mounted on the central shaft. In the standard configuration, the system has two inputs, two outputs, and an additional disturbance injection input. However, the platform has also been designed to be multi-configurable, allowing the number of inputs and outputs to be varied in order to expand the scope of the system. The test facility will be used to evaluate a significant number of Iterative Learning Control (ILC) schemes performing reference tracking tasks, and results will be compared with other control methods such as adaptive control, repetitive control and classical ILC methods