Design And Research On Automatic Steering Control System Of Tractor Seeding Opration

Automatic steering is an important part of the tractor automatic navigation, This study is the result ofon-the-spot investigation and fully understand the current research, according to Xinjiang’s regionalgeography, operating machinery, crop planting patterns and other characteristics, use TN654tractor for theindustry platform, design a automatic steering control system for automatic navigation, and tractorautomatic navigation path tracking algorithm is discussed.First,in accordance with the automatic steering function,It design principles proposed, and designswith five automatic steering actuator feasible solution, analyze their strengths and weaknesses;Comprehensive analysis of a variety of automatic steering, selected full hydraulic steering installationprogram for the final solution, front-wheel angle sensor model is WYT-AT-2, then selection and purchaseof hardware, design the installation bearings, completed the automatic navigation and installation;Accuracy testing laboratory to complete front-wheel angle sensor calibration and dual receiver GPS sensor.Then, It proposed of automatic navigation predefined path method; studied automatic steering controlalgorithm, use MATLAB simulation for the proportion algorithm and PD algorithm analysis, designed,dual-channel PD control algorithm for the automatic steering method, this algorithm can well completion ofthe automatic steering control tasks, one can solve the problem of asymmetric steering cylinder turnedaround; while also studied the path tracking algorithm, analyze the advantages and disadvantages of thedifferent path tracking algorithm, designed purely to do with the path tracking algorithm algorithm, useMATLAB simulation to study，Simulation results show that, when the lateral deviation is0.5meters, theheading deviation is0.5radian, the initial front wheel angle to0degrees, the best distance is2.5meters.Next, in accordance with the required navigation function, I selected LM3S5749for automaticsteering controller, IAR software development environment, application C language development;according to the requirements of the automatic steering control system to design control software, thesystem’s main functions, angular displacement sensor signal acquisition and processing, procedures toreceive and process GPS data, calculate the amount of control procedures, stepper motor control program,and debugging and testing the software modules and system to meet the design requirements.Finally, to verify whether the design features to achieve, to do some validation experiments, such asstepper motors turning experiments, software functionality testing laboratories; For optimal control system,the system is a bench test, including: dual channel coefficient tuning experiments, PD coefficient tuningcontrol algorithm experiments, when the double-channel coefficient is0.7, the scale factor is50, theDifferential factor is20, the best automatic steering,turning fast,stability,small overshoot.