双天线GNSS 精准平地控制系统试验

Test of Double Antenna GNSS precise level ground control system

关键词:  精准农业  平地机  双天线定位  智能控制

Key words:  precision agriculture  ballgrader  dual antenna positioning  intelligent control

摘要:

【目的】利用双天线GNSS 的精准平地系统可以达到提高土地平整度、提高肥料利 用率和降低水土流失的目的，可以提高农作物产量、提高平地机在不同地形作业的精度和 效率，减少农民的劳动强度。【方法】GNSS 精准平地控制系统通过GNSS 移动站接收到的 GNSS 差分站发送的差分信号确定平地铲的高程和姿态角，向控制器发送指令调节电磁换向 阀的开闭，通过控制液压油管中流量和流向实现实时精准调节平地铲高程和姿态角的工作目 标。【结果】1. 平整作业后土地最大高差从平整前的0.245 m 高差缩减到0.139 m，平整度显 著提升；2. 该试验平地铲最大姿态角为1°，即平地铲变化范围小，始终保持平稳；3. 试验 田平整后记录点到基准平面距离小于2.5 cm 的点占总试验田面积60% 以上，平地效果良好。 【结论】双天线GNSS 精准平地控制系统定位精确可以达到厘米级、稳定性高、不受拖拉机 行驶速度影响；液压系统响应快速，可以实现根据控制器信号精准调节平地铲高程和姿态 角；系统整体设计合理，平地效果达到精准平地要求。

Abstract:

［Purpose］Water resources and fertilizers are important for crop growth，but huge loss of water and fertilizer commonly happens on uneven farmland. Research shows that more than 20% of irrigation water and more than 30% of the fertilizer are wasted respectively because of uneven farmland surface.［ Method］By using the precise flat ground system of double antenna GNSS，the aim of improving land smoothness，increasing fertilizer utilization rate and reducing soil and water loss can be achieved，and the yield of crops can be increased，and the precision and efficiency of the leveller operation in different terrain can be improved. To reduce the labor intensity of farmers，the GNSS precise and flat control system moves through GNSS. The differential signals transmitted by the GNSS differential station received by the station determines the elevation and attitude angle of the flat shovel，and sends a command to the controller to adjust the opening and closing of the solenoid commutation valve. By controlling the flow rate and flow direction of hydraulic tubing to realize the real-time and accurate adjustment of height and attitude angle of the flat shovel.［ Result］The experimental results show that：（1） the maximum height difference of land after leveling operation is 0.245 m higher than that before leveling；the difference was reduced to 0.139m；flatness increased significantly；（2） the maximum attitude angle of the flat shovel in this experiment is 1°，which means the change range of the flat shovel is small，and is always stable；（3）the distance from the recording point to the base plane is less than that of the base plane after the test field is leveled. The 2.5cm point accounts for more than 60% of the total field area，and the ground levelling effect is good.［ Conclusion］According to the experimental results，the precise positioning of the double-antenna GNSS precise flat-ground control system can reach the centimeter level，the stability is high，and it is not affected by the speed of the tractor. The hydraulic system can accurately adjust the elevation and attitude angle of the shovel according to the controller signal，and the overall design of the system is reasonable and the effect of the flat ground can meet the requirement of precision and level.