Design of Feedback Variable Rate Spraying System Based on ARM

In order to realize variable rate spraying and ensure the spraying effect, a set of feedback variable spraying control system based on ARM was designed. The system takes the vehicular ARM controller as the core and adopts Linux operating system to obtain the information such as vehicle speed, liquid flow rate and pressure at the nozzle collected by the CAN bus. The system can online process the data and send the function code to the drive circuit, according to the input user's needs, to achieve realization of electric ball valve DC motor speed control under pulse width modulation. And then the current spraying quantity is changed, and ultimately based on the speed of the vehicle. The simulation test and actual vehicle test were carried out. The test results showed that the speed of the vehicle was 4 ~ 10 km/h and the control error of this system variable was less than 5%, which satisfied the requirement of variable spraying operation. Keywords—variable spraying; control system; ARM; CAN bus; precision agriculture