针对丘陵山区农业机械因体积小、种类多,难以无人作业改造的问题,搭建基于双预瞄纯追踪算法的丘陵山区农机差分导航系统,完成导航系统结构、路径规划策略和追踪控制器的设计.使用Ntrip DTU和北斗定位板卡完成差分定位.采用平滑转向方式,提出适用于丘陵山区的全局路径规划策略,可有效适配不同转弯半径的农机,减少地头区域.设计双预瞄纯追踪模糊控制器,开展与纯追踪控制器的对比仿真试验,并搭建试验样机完成测试.实际测试结果显示:控制器在追踪直线时,在s=2.9 m处收敛,在之后的直线追踪中平均绝对误差保持在0.01 m;在追踪曲线时,两段弯道最大误差分别为0.08 m和0.75 m,平均绝对误差0.04 m.
Research on differential navigation system of agricultural machinery in hilly areas based on dual preview pure tracking algorithm
In order to solve the problem that agricultural machinery in hilly areas is difficult to be transformed by unmanned operation due to its small size and many kinds,a differential navigation system for agricultural machinery in hilly and mountainous areas based on double preview tracking algorithm was built,and the navigation system structure,path planning strategy and tracking controller were designed.Ntrip DTU and Beidou positioning board card were used to complete differential positioning.A global path planning strategy suitable for hilly and mountainous areas was proposed by using smooth steering mode,which could effectively adapt to agricultural machinery with different turning radius and reduce field area.The dual preview pure tracking fuzzy controller was designed,and the simulation experiment was carried out compared with the pure tracking controller,and the experimental prototype was built to complete the test.The actual test results showed that the controller proposed in this paper converged at s=2.9 m when tracking the straight line,and the average absolute error remained at 0.01 m in the following straight line tracking.When tracking the curve,the maximum error of the two curves was 0.08 m and 0.75 m respectively,and the average absolute error was 0.04 m.