中文摘要：

分析车辆转向时各车轮的运动关系;针对我国农业的现状,提出一种基于阿克曼梯形转向结构的交叉变轮距底盘的技术方案;在交叉变轮距底盘的基础上,加入了线控转向系统,4个车轮由4个转向电机独立驱动,并保留转向盘和转向轮的机械连接。研究表明：该交叉变轮距底盘可较好地实现变轮距、前轮转向和四轮转向,而且应用线控转向系统可以提高汽车的转向性能,对农用机械的开发具有参考价值。

英文摘要：

The movement relationship between each wheel when the vehicle was steering was analyzed. According to the current agricultural situation of our country,a kind of crossing variable wheel track vehicle chassis technical solution which was based on Ackman trapezoidal steering mechanism was put forward. Based on the crossing variable wheel track vehicle chassis,the steer-by-wire system was joined,the four wheels were driven by four independent steering motors,and the mechanical connection between the steering wheel and wheels was reserved.The research shows that the crossing variable wheel track chassis can complete the changing of wheel track,front wheel steering and four-wheel steering. The application of steer-by-wire-system can improve steering performance of the car and has a reference value to the development of agricultural machinery.