Uay Emergency Parachute Drop Loss Avoidance And Landing Position System

With the widespread application of UAV and the increasing frequency of air operations,UAV consumers put forward higher demands for the safety of UAV itself and airborne equipment.However,there may be undetected security risks in UAV-related equipment,unforeseeable natural environmental impacts during the execution of actual tasks,as well as the reasons for the wrong operation of the UAV operator.Therefore,it is possible for the UAV to crash and damage the onboard equipment.At the same time,when the UAV crashes,the search and location of UAV becomes more and more difficult because of the influence of the geographical environment factors in the operation area.Thesrefore,an independent safety assurance system which can realize the function of loss avoidance and landing position of UAV has become an urgent need in the field of UAV application.In view of the actual needs of UAV in actual flight,this paper proposes the technical solution of" emergency parachute drop + landing position"after in-depth research and analysis of relevant technologies in this field.The embedded technology and Android development technology are used to design and realize the system,so as to escort the safe flight operation of UAV.The hardware of the system is divided into three parts:airborne unit,remote control gateway and mobile client.Among them,the airborne unit mainly completes the autonomous judgment of UAV's flight state,the sending of UAV's related data and the receiving of ground remote control command of opening/closing parachute compartment.The remote control gateway mainly completes the functions of networking with mobile client,receiving and forwarding of UAV related data,remote control opening/closing of parachute compartment by manual switch.The mobile client mainly completes the real-time positioning function of UAV.The system software mainly includes:"free fall judgment"algorithrm,"flip Angle judgment"algorithm,"flight height judgment"algorithm.Among them,the"free fall judgment"algorithm is used to determine that the UAV is out of control after it enters the free fall motion state."Flip Angle judgment"algorithm is used to determine that the UAV is out of control when its body tilts exceeds a certain Angle."Flight height judgment"algorithm includes"parachute opening height" algorithm and"flight height change rate"algorithm,among them,the"parachute opening height"algorithm is used to set the reasonable parachute opening height of the UAV so that the final landing range of the UAV can be effectively reduced,"Flight height change rate"algorithm is used to eliminate the influence of horizontal external forces(such as wind)on UAV,so that the losing control judgment of UAV is more accurate.The system has a certain ability of data self-processing,and has the strong characteristics of good real-time and fault-toleran performance.The system can not only run stably independently of UAV flight control system,but also realize real-time acquisition of UAV flight attitude data,which provides reliable data guarantee for autonomous judgment of UAV out of control state.At the same time,the real-time acquisition of UAV positioning data can be used to draw the UAV flight path and locate the landing point,which provides convenience for the search of UAV.