The Auto Control System of Dome's Window-Blinds at Lijiang 2.4m Telescope

Super-hemispherical dome with tracking and sliding devices was built for Lijiang 2.4m optical telescope, and as an important part of the dome, window-blinds were designed to reduce the turbulence which was caused by enclosure itself and electric devices. But windows-blinds need to be operated manually on high platform with risks and long time, which also made them fragile. Now they can be controlled automatically after transforming their mechanical structure. The auto control system's architecture is that host computer controls the embedded system in STM32 board through interface of WiFi module, serial port, or handles to realize multi-channel control. The STM32 board, as the slave part, provides the PWM to DRV8255 to drive the stepper motor. In this way, we realize the automatic control, and further on we call telescope's DB and set the threshold of weather parameter in order to control the dome more accurately. Through a month of trial, the system is stable, reliable, and can meet the needs of observation.