农机自动导航控制决策方法与软件系统

为实现农机自动导航控制,兼顾系统成本和作业效率,对农机自动导航控制决策方法进行了研究,并设计开发了一种导航软件系统。首先,系统根据获取的农田边界、农田形状及作业需求进行路径规划。其次,采用简化二轮车运动学模型,采用模糊控制进行导航决策控制,模糊控制器的输入参数为农机横向偏差和航向偏差,输出参数为前轮转角信息。最后,导航系统根据转角信息,由PLC控制器控制方向盘转动,从而实现导航控制。导航软件采用模块化设计思想,由串口数据通讯、数据分析与处理、数据与图形显示和数据存储4个模块构成,基于C++/MFC语言编写实现。系统还可在导航结束后,对导航偏差数据进行保存,便于试验后进行误差分析。试验结果表明：农机自动导航控制决策方法可以实现较好的控制精度,软件系统界面友好、通讯稳定、功能较为齐全,满足农机田间自动导航作业的需求。

Decision Control Method and Software of Automatic Navigation System for Agricultural Machinery

In order to realize agricultural machinery automatic navigation control, and taking into account the system cost and operation efficiency, the automatic navigation control decision method was studied, and a navigation software system was designed and developed. Firstly, the system conducted path planning according to the field boundary, the field shape and working requirements. Secondly,the simplified two-wheel vehicle kinematic model was used and the fuzzy control was adopted for navigation control decision. And the input parameters of the fuzzy controller were the lateral deviation and the heading deviation of agricultural machinery, and the output parameter was the steering angle data. Finally, using the steering angle data, the machine was controlled by the steering wheel through PLC controller. The modular design ideas were adopted in software development. The software mainly consisted of four modules: serial data communication, data analysis and processing, data and graphic display and data storage. It was developed based on C++/MFC programming language. The software can analyze and process the received data, such as GNSS positioning data, angle sensor data, attitude sensor data and PLC controller data, then send the corresponding control decision information to the PLC controller. In addition, the system can store the deviation data for error analysis after the navigation. The experimental results demonstrated that the automatic navigation control decision method can achieve preferable control precision. The software has user-friendly interface, stability communication and relatively complete function, so that the proposed automatic navigation control decision and software system can meet the field operation requirements for agricultural machinery.