基于RTK-BDS的无沟铺管机作业高程控制系统研究

针对农田铺管装备采用传统激光高程控制技术控制精度低、适应性差的问题，设计了基于载波相位实时动态差分北斗卫星定位系统(RTK-BDS)的无沟铺管机高程控制系统。该系统以RTK-BDS为核心，以V型犁式无沟铺管机为作业对象，采用多模型UKF多传感器信息融合算法获取高精度海拔高度信息；利用多模态模糊PID算法控制高程油缸，从而满足犁头按照指定坡降指标工作的需求。田间试验表明，多模型UKF算法较无迹卡尔曼滤波(UKF)、粒子滤波的滤波效果更好，其波动幅度降低至0.885cm，均方差降低至0.040cm，多点相对误差在±0.2cm之内；不同坡降高程控制的控制误差均在±2cm之内，平均误差小于1cm，满足无沟铺管机的作业需求。

Elevation Control System of Trenchless Pipe Installation Machine Based on RTK-BDS

Aiming at the problems of traditional laser elevation control technology, low control accuracy and poor adaptability of farmland pipe laying equipment, an elevation control system of trenchless pipe installation machine based on RTK-BDS was designed. The system was mainly composed of elevation detection system and elevation control system. The elevation detection system took RTK-BDS as the core, combined with the middle frame structure, used acceleration sensor, pulled wire sensor and other sensors, and adopted the multi-sensor information fusion algorithm of multi-model UKF to obtain high-precision altitude information;the elevation control system mainly controlled the height of the plow through the proportional valve control oil cylinder, and through the analysis of the mathematical model of the elevation oil cylinder control, the design was completed. The multi-mode fuzzy PID control algorithm was used to control the expansion and contraction of the oil cylinder, so as to realize the working requirements of the plow according to the specified slope index. Through the static test, UKF, particle filter and multi-model UKF algorithm were used to detect the elevation information. The test showed that the filtering effect of multi model UKF algorithm was better, and the maximum relative detection error was 0.181cm, and the average relative error was 0.051cm. In the dynamic situation, the tracking effect was better and the relative error was smaller. Through the field test, the elevation control experiment without slope, the elevation control experiment with slope and the comprehensive experiment were carried out. The results showed that the elevation control error can be kept within ±2cm, which can meet the requirements of pipe laying by trenchless pipe laying machine.