Leveling control system of laser-controlled land leveler for paddy field based on MEMS inertial sensor fusion

Plow leveling control is indispensable for laser-controlled land levelers intended for paddy field work. The authors present an efficient low-cost design of such a leveling control system, among which their main features are: monitoring the plow’s inclination by fusing two MEMS inertial sensors, i.e. one accelerometer and one gyroscope; and pulse width modulating two ordinary hydraulic solenoid valves as actuators to regulate the plow’s leveling. The makeup of the whole leveling system, function of each sensor and their installation on the plow are presented. A full sensor data fusion method for measuring real-time plow inclination is then thoroughly analyzed, with an implementation description on an ARM7-based embedded control system provided in terms of electronics hardware design and software flowchart. Finally, experimental results are presented based on the comparisons between fused data and reference data from an AHRS instrument, showing that the proposed fusion method gives quite accurate inclination information of the plow and the whole leveling system works reliably.