Fractional position estimation for optical incremental encoder based on FPGA

Robust control systems have become very important in the industrial field. In these control systems estimate the input / output (position, velocity and acceleration) plays an important role in order to obtain high performance. Therefore, in this paper a novel method for fractional position estimation based on FPGA(Field Programmable Gate Array) is proposed. Short processing time in the FPGA helps to generate fractional position at every sampling time. Then, the motor position is the result of adding position from optical incremental encoder and the fractional position. The results are obtained through simulation and experimentation with an optical incremental encoder as a position sensor. The high resolution motor position is determined by the short processing time in the FPGA, but the quantization error is reduced in proportion to the sampling time.