Research On Modeling And Control Strategy Of Parachute Recycling System For The UAV

The parachute recovery process for unmanned aerial vehicle (UAV) is an important stage amongthe entire flight missions. The UAV will be damaged if the landing position can’t be correctlyestimated. So a reasonable model of UAV parachute recovery system and rational control strategyplay an important role in engineering applications. For the unreasonable previous model together withunclear study of the trajectory of the system as well as the imperfect control strategies, the study ofmodeling and control strategy were carried out in this paper starting from the accuracy of the actualUAV parachute recovery needs.The opening speed of the umbrella, full canopy conditions, resisitance characteristics and qualityfeatures are studied first in the paper, and the motion characteristics of the recycling process sianalysised, so the6DOF mathematical models of the UAV and parachute system were built againstthe characteristics of each stage, which providing foundation for the study of the system trajectories.Secondly, the trajectory of the recycling process has been studied based on the model, includeunpowered flight trajectory, parachute deceleration trajectory and steady drop trajectory. Besides, theimpact of the wind and attitude for the entire trajectory were studied, which provided the basis for thecontrol strategy. Finally, this paper gave the control strategy of before recovery, unpowered segment,deployment and cutting segment of the parachute according to the factors that influence the trajectory,which gave technical support for the actual recovery.There formed a relatively complete framework for UAV parachute recovery system throughthis paper. Combined with the analysis of landing probability in a specific area for the UAV inpractical application, this paper gives the probability of landing circle. The results show that theproposed method has good placement-controlling ability and can meet the requirements of therecycling accyracy.