Servo Control Design of a Micro/Nano Positioning Stage Using FPGA Based Embedded Hardware

摘要

It is well known that piezoelectric based microano positioning stages have been widely applied to a vast amount of precision engineering applications due to their fast speed and high resolution in fine range motion control. To improve system compatibility and portability, recently embedded processor based implementation platform has become an attractive option for practitioners. This paper presents servo control design of a microano positioning stage using FPGA based embedded hardware. The study applies two advanced digital control algorithms, neural network control using radial basis function and repetitive control, to track a periodic triangular reference profile for precision scanning applications. The applied controls and the system identification process for the repetitive controller design were realized using a fixed-point FPGA based embedded platform under a LabVIEW GUI environment sampled at 10 kHz. The experimental results on a self-developed microano positioning stage and performance analysis demonstrate that the stage achieves good tracking control performance even with consideration of finite word length issues in embedded hardware.