Design of L1 -Adaptive Controller for Single Axis Positioning Table

Abstract

L1 adaptive controller has proven to provide fast adaptation with guaranteed transients in a large variety of systems. It is commonly used for controlling systems with uncertain time-varying unknown parameters. The effectiveness of  L1 adaptive controller for position control of single axis has been examined and compared with Model Reference Adaptive Controller (MRAC). The Linear servo motor is one of the main constituting elements of the x-y table which is mostly used in automation application. It is characterized by time-varying friction and disturbance.

    The tracking and steady state performances of both controllers have been assessed for two different types of input signals ramp and step inputs. The simulated results based on MATLAB (2012a) package showed that L1 adaptive controller could outperform MRAC in terms of robustness and tracking.