Performance Improvement of Motion Control Systems with Low Resolution Position Sensors using MEMS Accelerometers

This paper presents a use of MEMS accelerometers for performance improvement of motion control systems equipped with low resolution position sensors. It is well-known that control performance depends on hardware performance such as a sensor resolution and a computational power. Above all, the use of low resolution sensors restricts the achievable enhancements on the control bandwidth, due to quantization noise. In this paper it is proposed to overcome such limitation by using a Kalman estimator, utilizing the measurements provided by a low cost MEMS accelerometer in the estimation of position information. Moreover, the same measurement is used for the acceleration based disturbance observer (a-DOB), where no differentiator is needed to estimate the disturbance, so that a better estimation capability and positioning performance can be achieved. The effectiveness of the proposed control system has been verified by several experiments using a prototype of a table system.