Research On Coverage Path Planning Technology Of Unmanned Agricultural Equipment Based On BCD Principle

At present,the labor cost of agricultural operations is continuously increasing,which results the continuous increase of production costs of agricultural operations.With the development of the intelligence and precision of agricultural equipment,unmanned agricultural equipment has become an excellent solution to replace the current expensive labor costs.Compared with manual operation,the path planning technology of unmanned agricultural equipment can improve the straightness and coverage of the operation route,and has the advantages of high efficiency and low cost.However,there are various obstacles in the farmland environment,which requires path planning technology to be able to avoid obstacles based on high efficiency working performance.Therefore,path planning technology has become a hot and difficult point of current research.The main research work of this paper is as follows:First,the research status and development trend of unmanned agricultural equipment and full coverage path planning algorithms at home and abroad are analyzed,and the advantages and disadvantages of the algorithms were analyzed and discussed.Through investigation,the path planning algorithm of the unmanned agricultural equipment in this paper was determined.Using the working width of the working machine as the standard,the obstacle position is judged,and the distance of the obstacle is obtained by analyzing its relative position and absolute position.If the distance is less than the working width,the obstacle fusion operation is performed.In view of the difficulty of planning a route in a complex map,the unit decomposition method was used to decompose the map,and the whole map is decomposed into sub-maps of simple geometric shapes.The path planning angle of the map area is mostly horizontal or vertical.A path planning method was proposed.Set the guide line by positioning the extreme points of the plot,and realize the planning angle change by adding and subtracting the value of the guide line.By using the line-line intersection formula to determine the intersection point between the path and the farmland boundary,and obtain the obstacle avoidance route for obstacles by using the line-circle intersection point.In order to obtain the work effect of the algorithm and the most significant factors that affect the work effect of the algorithm,its performance was tested.The first is a single factor test,which aims to test the influence of changes in the corresponding independent variable factors on the performance of the system.The experiment set up two groups.One group uses grouping method for path planning,and the other group does not use grouping method for path planning.The single factor test results show that the working distance proportion of the two methods will decrease due to the angle change,the number of obstacles increases and the length of obstacles increases,showing a negative correlation.The coverage area proportion of the grouping method was maintained above 96%,and the repetition rate was less than 1.6%.When the planning angle of the non-grouping method is 30° and 15°,the coverage area ratio was greatly reduced because the farmland was divided by the boundary,and the minimum coverage area proportion was only 88 %,so the planning quality of the grouping method is significantly better than that of the non-grouping method.Through linear regression analysis in multi-factor experiments,the significance ranking of factors affecting the effective length ratio is: path planning angle> obstacle number> obstacle length.The significant factor affecting the land coverage area ratio is the path planning angle.Therefore,in the use of the algorithm,it is necessary to select a suitable path planning angle according to the long side of the plot to achieve the optimal effect.