Research On Complete Coverage Path Planning And Tracking Control For Horticultural Electric Tractor

Agriculture is the foundation of the national economy.The key to ensure food supply and food security is to promote the advancement of agricultural production technology.In this paper,combined with Jiangsu Province Key R&D Plan(Modern Agriculture)-R&D of Horticultural Electric Tractor(BE2017333),the complete coverage path planning and tracking control technology of the horticultural electric tractors were studied to improve the intelligent level of horticultural electric tractors and reduce the labor intensity of operators.The specific content of this paper are as follows:Firstly,the research background and significance of complete coverage path planning and tracking control for horticultural electric tractors were reviewed,and the research status of related fields such as navigation and positioning technology,path planning technology and trajectory tracking control technology were analyzed,and the specific research contents were clarified.Secondly,the complete coverage path planning algorithm for horticultural electric tractors was studied.The grid method was used to construct a 2.5D working environment model of the horticultural electric tractors;the improved heritage algorithm was used for complete coverage path planning,and the coding method combining the rectangular coordinate method and the serial number method was proposed.Based on the search principles of high coverage rate,low energy consumption and low repetition rate,the multi-objective of the plane driving path length,the number of turns and the total elevation difference of the genetic algorithm is established.Meanwhile,the crossover and mutation factors of the genetic algorithm are improved,and the simulation and comparison experiments were carried out under a variety of operating environment models.The experimental results showed that the complete coverage path planning based on the improved genetic algorithm can be used in different operating environments.Thirdly,aiming at the problem of poor comprehensive tracking performance of the trajectory tracking controller predicted by the model with a constant weight coefficient under different working conditions,the influence law of weight coefficient change on trajectory tracking comprehensive performance was studied.Based on the fuzzy control strategy,a model predictive trajectory tracking controller with adaptive weight coefficients was designed.The Simulink/Carsim co-simulation results showed that the trajectory tracking controller based on the adaptive weight coefficient can give consideration to the tracking accuracy and driving stability at the same time,and the comprehensive performance was better.Finally,the installation and automatic transformation of the horticultural electric tractor trajectory tracking control test platform were carried out.Based on the real-time dynamic positioning technology of the Beidou navigation system,the trajectory tracking test of the horticultural electric tractor was carried out.At the same time,the equivalence test of the software in the loop was carried out to verify the consistency of the behavior between the generated code and the model used for code generation,and the tracking control algorithm was transplanted to carry out the trajectory tracking test of the electric horticultural tractor under different working conditions.The test results showed that the navigation and tracking system of horticultural electric tractor has good comprehensive performance.