Control method of stepping motor for spaceborne solar irradiance spectrometer

The encoder is not included in the hardware design of the Spaceborne Solar Irradiance Spectrometer, so in this paper, a high precision control method of stepping motor is proposed, which can position accurately without encoder. When the wavelength scanning mechanism is controlled, the validity of the hall signal is judged by controlling the forward and reverse rotation of the motor and the fixed steps of the motor. When the hall signal is valid, the operation of returning to the starting position is performed normally. The motor drive is subdivided into 16 substeps, and each substep is only 0.1125°. The control method of turntable mechanism is to quickly return to the starting position, after overshoot, one-step reverse rotation with appropriate delay to move out of hall effective area, and then identify the starting position. The experimental results show that the method can meet the requirements of wavelength repeatability less than 0.01 nm, wavelength calibration accuracy less than 0.05 nm, and calibration accuracy stability less than 0.2%. At the same time, the volume and weight of the system are reduced, and the miniaturization of the system is realized.