Simulation On Flight Dynamics And Control Of Parafoil Airdrop Systems

The traditional parachute recovery has the disadvantages of low precision and large scatter distribution,the parafoil system has excellent gliding performance,good stability and maneuverability,it has a wide and important application in aeronautics and astronautics,military and civil fields.Therefore,it is very important to research the airdrop system of parafoil.Firstly,in order to analyse the dynamic characteristics of the parafoil system,the nine degree of freedom dynamic modeling is established,the basic kinematic characteristics such as gliding,flare maneuver and turning of the parafoil system are obtained by simulation,the influence of parafoil's rigging angle,mass of payload and drag characteristics aero of the payload on the flight performance of parafoil system is analyzed,the influence of wind on the parafoil system is analyzed,it is shows the deviation along the wind direction and the drift speed is close to the wind speed.Secondly,according to the fixed point landing of parafoil system's task,the method of multiphase homing is used to design the parafoil's homing trajectory,improving the accuracy of the landing point and reducing the energy consumption as the goal,the problem of trajectory planning is transformed to parameter optimizing,different homing projects are designed base on the initial height of the parafoil,the effects of different control mode on trajectory planning is also considered.Thirdly,aiming at the problem of parafoil homing trajectory tracking control by setting up the PID control system,the co-simulation method is used for tracking control of Parafoil homing trajectory,the change law of the parafoil's speed,the change law of the control quantity and the trajectory tracking curve are obtained,and the influence of the wind condition on the trajectory tracking is analyzed.Finally,Monte Carlo method is used to simulate the landing point,considering the effects of factors such as aerodynamic characteristic deviation,payload's mass deviation and wind disturbance on the landing point,it greatly reduces the cost of airdrop test and provides the basis for the parafoil's landing point dispersion.