Adaptive Optics Tip-Tilt Correction Based on Smith Predictor and Filter-Optimized Linear Active Disturbance Rejection Control Method

Abstract

A tip-tilt mirror (TTM) control method is designed to enhance the control bandwidth and ensure the rejection performance of the adaptive optics (AO) tip-tilt correction system. Optimized with the Smith predictor and filter, linear active disturbance rejection (LADRC) is adopted to achieve the tip-tilt correction. An AO tip-tilt correction experimental platform was built to validate the method. Experimental results show that the proposed method improves the control bandwidth of the system by at least 3.6 times compared with proportional–integral (PI) control. In addition, under the same control bandwidth condition, compared with the Smith predictor and proportional–integral (PI–Smith) control method, the system is more capable of rejecting internal and external disturbances, and its dynamic response performance is improved by more than 29%.

An Optimal Integral Controller for Adaptive Optics Systems

“…However, despite the progress made in AO technology, there are ongoing challenges related to modeling and mitigating disturbances in modern AO systems [2][3][4][5][6][7][8][9][10]. Accurate models that describe the dynamics of the AO system [11][12][13][14] and precise models for disturbances such as turbulence and vibrations are essential when implementing effective control techniques to mitigate these aberrations.…”

“…By reducing the output variance, the performance of the AO system can be optimized and improved image quality can be achieved. While recent efforts in advanced control techniques have been reported in the literature [9,10,[23][24][25], there has been limited research focusing on the optimization and tuning of integral controllers in today's astronomical AO systems.…”