Research On Routing Planning Algorithm Of Rice Transplants

With the development of science and technology,the rice transplanter and all kinds of advanced technologies have been integrated and innovated.With the increasing aging of population and the acceleration of land transfer,the demand of unmanned rice transplanter is more and more urgent,which can effectively solve a series of problems caused by manual operation.The research on path planning is an important part of realizing the autonomous operation of rice transplanter,which can effectively improve the working efficiency and coverage of transplanter,and provide the basis of path navigation for the realization of unmanned transplanter.The main research is as follows:According to the working environment of transplanter,the environment model is established,which lays the foundation for the research of obstacle avoidance algorithm.Through the analysis and comparison of common modeling methods,the grid method is selected to establish the environmental model of rectangular land.Considering that the shape of obstacles(electric poles and electric piles)in farmland is not conducive to the description of environmental information by grid method,the binary expansion algorithm is used to deal with it,and the processed obstacle boundaries coincide with the grid boundaries,which can effectively improve the accuracy of path planning.Through the research and analysis of field full coverage operation mode,a compound covering mode combining round-trip and external spiral covering mode is proposed to improve the coverage rate of operation path.For the problem of path obstacle avoidance,a path avoidance algorithm combining A~*algorithm and Bezier curve is proposed,which can accurately avoid obstacles,and the obstacle avoidance path is smoother and more conducive to the transplanter walking.Combined with the working nature of transplanter,the boustrophedon method is selected.According to different operation paths,the shortest turning path under different land turning strategies is analyzed.This paper proposes a coordinate marking method by selecting the bow turning strategy,and gives different symbols to the path points of the transplanter at different positions,which is convenient for observation and data collection.Combined with the path research of work area and turning area,the overall path planning schemes in two different situations are summarized.For the composite coverage mode,through data analysis and verification:compared with the single round-trip mode,the coverage rate of this coverage mode is significantly improved,which meets the path optimization standard.According to the selection of convex polygon ridging operation direction,a Pentagon plot is selected.Through simulation and data analysis,it is concluded that the highest coverage rate and the least number of turns can be obtained for ridging operation parallel to the longest boundary of the block,which is the best operation direction.Aiming at the proposed coordinate marking method,the feasibility of the algorithm is verified by simulation experiments in Python environment,which provides theoretical support for unmanned rice transplanter.