高速插秧机自动转向系统研制

Development of an Automatic Steering System for a Rice Transplanter

高速插秧机的液压助力转向装置为整体式安装,不能通过并联油路的方式实现其自动转向。为此,研制了以无刷电机作为动力源的电动自动转向系统,主要包括转角传感器、转向控制器、无刷电机及其驱动器和辅助传动机构。转角传感器用以测量高速插秧机的前轮转向角,转向控制器读取前轮的转向角度,基于数字PID控制方法计算无刷电机的旋转速度和旋转方向并将控制信号发送至电机驱动器。田间测试结果表明:自动转向系统在[-10°,10°]范围内的转向控制误差小于1°、均方根误差小于1°,具备良好的控制稳定性和可靠性,能够满足高速插秧机田间自动导航的基本要求。

It is not feasible to realize automatic steering for rice transplanters by by-passing hydraulic steering mechanism because of their adopting integrated hydraulic steering devices. In this research,we developed an electric automatic steering system by using a brushless motor to provide steering torque,which was comprised mainly of an angle sensor,a steering controller,the brushless motor and driver and transmission mechanisms. The angle sensor was used to measure the steering angle of the front wheels. Based on the PID algorithm,the steering controller calculated both rotating speed and direction and sent signals to the motor driver. Field experiments showed that the steering control error was less than1 degree and its RMS error was less than 1 degree in the range [-10°,10°]. This indicated that the newly developed steering system was accurate and reliable in steering control and could meet requirements for automatic navigation of rice transplanters.