Cooperative And Precise Operation Method Of Multi-sprayer-UAVs Based On Path Planning

With the development of modern agriculture in China,the demand for high-quality agricultural equipment is increasing.Using unmanned aerial vehicle(UAV)for aerial spraying is an important manner to improve the spraying quality and efficiency.After reasonably planning the operation path,multi-sprayer-UAVs are used for cooperative and precise operation(CPO)to achieve on-demand application of pesticides according to the damage degree of crop diseases,which can effectively improve the operation quality,reduce environmental pollution,and improve labor efficiency.Based on the farmland prescription map and cooperative path planning(CCP),a CPO method of multi-sprayer-UAVs was proposed in this researchA full coverage operation route generation model based on Zig-Zag method was established,and a method for automatically dividing the operation area of each UAV under a single spray area was proposed.The generation methods of farmland prescription map based on disease area boundary information and sub-area image recognition were respectively proposed,which provided a basis for CPO of UAV.Taking the total numbers of sorties,total replenishment time,total operation time,minimum replenishment interval and total numbers of boundary return points as optimization objectives,a CCP model for multi-sprayer-UAVs was established.The improved particle swarm optimization(PSO)algorithm was designed to solve the model,and the return sequence and position of each UAV were optimized.Compared with the maximum operation distance planning and simple planning,the advantages of the proposed method in cooperative operation were verifiedAccording to the operation requirements of the farmland prescription map,the maximum drug loading constraint was imposed.The CPO model of multi-sprayer-UAVs was established based on the CCP model,and the PSO algorithm was designed to solve it.Instance verification showed that the CPO method proposed in this research reduced 7.7%～18.3%,7.6%～31.2%and 0.4%～2.5%respectively compared with the maximum operation distance planning and simple planning in terms of the total replenishment time,the total round-trip flight time and the total operation time.Especially,the method proposed in this research could effectively allocate the replenishment time of each UAV,which indicated that this method had some practical value.The obtained CPO solution was input into the simulation software,which verified the correctness and feasibility of the CPO method proposed in this research.In view of the problem that the original operation scheme needed to be adjusted when an UAV broke down,a cooperative operation re-planning(CORP)method under the condition of an UAV leaving the team was proposed on the basis of the CPO method.Finally,several re-planning cases verified the effectiveness of the CORP method proposed in this research.