Abstract：With the development of agricultural aviation technology，the autonomous operation mode is a hi-tech research focus in the field of agricultural aviation.Plant protection unmanned aerial vehicle is an intelligent agricultural equipment that integrates various related technologies such as communication technology，automatic control technology，sensing technology and geographic information positioning technology.Spraying pesticides on crops is an effective method，with several advantages，including high speed and high efficiency.The unmanned aerial vehicle can take off and land vertically on a small area without a runway，making it easy to spray on various terrains.With the development of satellite positioning technology，the autonomous flight operation mode based on global positioning system navigation and capable of automatically generating drone operation routes according to the target area has become the main development trend of plant protection drones.Research on the route planning for unmanned aerial vehicles is particularlynecessary.A route planning algorithm based on hybrid particle swarm optimization was proposed for theobstacle-containingoperationarea.The route planning algorithm was divided into path point sampling and path point sorting.In our unmanned aerial vehicle route planning method，the path points on work area were sampled based on grid method and all effective path points were obtained.The unmanned aerial vehicle route planning problem was transformed into a sorting problem for the path points.The sorting problem for the path points was a combinatorial optimizationproblemthatcouldbesolvedusinganintelligentoptimizationalgorithm.The path points were sorted based on Hybrid Particle Swarm Optimization.The number of turns of the path was used as a criterion for evaluating the meritsofthe route.Comparative simulation experiments were performed in six different work areas.The experimental results showed that the number of turns of the route designed by the route planning method proposed in this paper were 36，34，27，40，46 and 37 times respectively.The number of turns of the route designed by the comparison method were 60，60，60，50，54 and 46 times respectively.A route which could effectively keep away from all obstacles and complete full coverage of work area was designed.The experimental results show that the proposed unmanned aerial vehicle route planning method can be applied on a variety of work areas with single or multiple obstacles.Routes of unmanned aerial vehicle are planned before operation，and then let the drone operate according to the specified route.The energy and pesticide consumption generated by unmanned aerial vehicle can be estimated in advance.Operating in this mode can save the time required for preparation and increase the efficiency of unmanned aerial vehicle operations.As the popularity of unmanned aerial vehicle increases，the operation and management of unmanned aerial vehicle becomes more and more important.The route planning method proposed in this paper is applicable to automatic unmanned aerial vehicle and can be widely used in precision agriculture.
2020, Vol. 41 
