Research On Automatic Navigation Control System Of Agricultural Tractor

Tractor is an important agricultural production tool and has a wide range of applications in agricultural production.The development of automatic navigation operations for tractors will greatly benefit the improvement of the efficiency of agricultural operations,the reduction of labor intensity of farmers,and the improvement of land utilization.With the increase of labor costs,the promotion of automatic navigation systems can also save the cost of farming and harvesting,and promote the development of agriculture.At present,the need for further research on the automatic navigation operation of the tractor is how to improve the working accuracy of the system,especially after the vehicle speed is increased,the vehicle running error is more obvious.The factors that cause errors are related to the accuracy of the positioning element,the response speed of the hydraulic element,and the selection of the control program parameters.This article mainly analyzes and studies the steering system of the automatic navigation tractor.It begins with the global satellite positioning system and introduces the principle of navigation and positioning.It also analyzes the hydraulic steering system of the tractor,based on the original manual steering system of the tractor.The installation of automatic steering system,the design of hydraulic principles,electronic control principles,and component selection.Second,a theoretical analysis of the hydraulic system.A mathematical model of the steering control element was established and a closed-loop control system was established and simulated in the AMESim software.The ECU program is written in BODAS software and the PID control strategy is applied in the steering control program to make the steering system more stable and accurate.Finally,a field experiment was conducted on a 40m×60m outdoor experimental site to test the actual working performance of the system,allowing the vehicle to travel at a speed of 3km/h,5km/h,and 8km/h respectively for 60 m.The experimental data was recorded,and debugging was performed according to the error conditions.Adjust the relevant parameters in the control program.In the control program,the deviation distance and the control current of the reversing valve and the energizing time are set as a functional relationship.The testing is performed again and the error data is collected.The measured error values are plotted as a chart for analysis.After the adjustment,the walking deviation was significantly reduced.