1 Control and System Eng. Dept., University of Technology

2 Al-Mansour University College, Baghdad- Iraq


In the present work, the design of an L1 adaptive controller for
position control of a linear servo motor for X-Y table application has been
developed. The AC Permanent Magnet Linear Synchronous Servo Motor
(PMLSM) is considered. A comparative study between L1 adaptive control and
Model Reference Adaptive Control (MRAC) has been made. The effectiveness of
the L1 adaptive controller against uncertain parameters is analyzed based on
simulated results. Robustness characteristics of both L1 adaptive controller and
model reference adaptive controller to different input reference signals and
different structures of uncertainty have been evaluated. The L1-adaptive
controller could ensure uniformly bounded transient and asymptotic tracking
for input and output signals. Simulations based on MATLAB of an x-y table
based on PMLSM with time-varying friction and disturbance are presented to
verify the theoretical findings. The simulation results within the environment of
MATLAB/SIMULINK showed that L1-adaptive controller could give better
tracking performance, dynamic and steady-state characteristics, than that
obtained from MRAC for considered types of input and for various structures of