一种与行驶速度无关的农机路径跟踪方法

针对智能农机自主作业中的路径跟踪控制问题,提出了一种与行驶速度无关的农机路径跟踪方法,该方法对农机行驶速度的变化具有鲁棒性。首先建立了空间参数驱动的非线性相对运动学模型,并证明了基于该模型进行控制方法设计的合理性和可行性。然后对此模型进行反馈线性化和最优控制设计,得到了一种与速度无关的农机路径跟踪控制律。最后进行了实车的路径跟踪实验,实验结果表明该方法的直线路径跟踪精度为4 cm,曲线路径跟踪精度为7 cm,且跟踪精度不受速度变化的影响,验证了该方法的有效性和对速度变化的鲁棒性。

Agricultural Machine Path Tracking Method Irrelevant to Travel Speeds

An agricultural machine path tracking method irrelevant to travel speeds, aiming at the path tracking control problem in autonomous operations of intelligent agricultural machines, was presented. The method was robust to changes in travel speeds of agricultural machines. Firstly, the space parameter driven nonlinear relative kinematics model between the agricultural machine and the tracked path was deduced and the rationality and feasibility of designing control method based on the model was proved. Secondly, the paper dealt with the model by input state linearization and utilized the optimal control method to stabilize the linear model obtained by feedback linearization, and an agricultural machine path tracking control law irrelevant to travel speeds was then obtained. Finally, path tracking experiments of an agricultural machine were carried out. The experimental results showed that the precision of straight path tracking and curve path tracking were 4cm and 7cm respectively and not affected by changes in travel speeds. Therefore the effectiveness and robustness of the proposed method were verified.