拖拉机自动导航单因子控制系统设计

针对当前拖拉机自动导航转向控制系统结构复杂、算法繁琐及对上位所检测机位置姿态信息要求较高等特点,设计了一种基于51单片机为中央控制载体的拖拉机自动导航执行系统。本系统在不改变原车的液压转向控制系统的前提下,通过加装以步进电机为动力的驱动装置带动方向盘转动实现前轮转向;同时利用角度传感器不断检测前轮转角,为系统在进行转向决策时提供反馈,并且在执行过程中采用涡轮电机控制齿轮啮合与分离。控制系统采用单因子补偿控制算法,通过判断当前车辆的横向偏差走势判断当前的车身偏角。为验证程序算法以及结构设计的可行性,以TN954为实验对象,构建了转向系统和车身偏角的数学模型,运用Matlab/Simulink进行仿真。结果表明:拖拉机以3 km/h作业速度行驶时,在初始横向轨迹偏差设定在5 cm的调整过程中,稳态误差达到2%,单因子补偿控制算法所需的平均调整时间为1. 4 s,满足当今拖拉机自动驾驶控制实时性的要求。

Design of Single Factor Control System for Tractor Automatic Navigation

A tractor automatic navigation system based on 51 single chip computer was designed to solve the problem that traditional automatic steering control system was too complex and the complexity of the algorithm as well as the high demand of the position attitude.Under the hydraulic steering control system of the original vehicle,the system drived the steering wheel by adding the driving device with stepper motor as the driving force to realize the front wheel turning,meanwhile,using the angle sensor continuously detect the front rotation angle,provide feedback for the system in making the steering decision.And in the process of the implementation of the use of turbine motor control gear meshing and separation.The control system adopts single factor compensation control algorithm to judge the current vehicle deflection angle by judging the current lateral deviation trend.In order to verify the algorithm and the feasibility of the structure design,taking TN954 as the experimental object,the mathematical model of steering system was constructed,and the matlab/simulink was used to simulate.The simulation results show that when the tractor moves at a speed of 3 km/h,the initial lateral trajectory deviation is set at 5 cm.The average adjustment time required by the steady-state error of 2%single factor compensation control algorithm is 1.4 s,which meets the real-time requirements of tractor autopilot control.