Research On Dynamic Modeling And Homing And Controling Technology Of Parafoil System

With the rapid development of the parafoil airdrop technology,parafoil has been widely applied in military and civil aviation fields because of its excellent maneuverability.Parafoil homing control problem has become a hot research topic.At home and abroad have carried out many precise airdrop projects and achieved certain results currently.This paper adopts theoretical analysis and experimental simulation schemes to study the parafoil homing control problems.First of all,parafoil kinematics and dynamics equations are analyzed then the effect of trailing edge flap partial for aerodynamic force is introduced to establish a parachute model with six degrees of freedom.Besides,the steady state motion process and mechanical relationship of parafoil are further analyzed to simply the six degrees of freedom model to the steady-state parafoil model with four degrees of freedom.The operational relations between parameters of the models are also derived in the paper.Secondly,the multi-phase homing algorithm are adopted to study the route planning.The flight characteristics of parafoil based on the four degrees of freedom model,combined with the geometric properties of sectional homing trajectory are used to establish the objective function for solving trajectory.The improved artificial fish swarm algorithm is used to optimize the objective function and obtain the design parameters of trajectory.Furthermore,the rationality of trajectory design is verified by simulation.Thirdly,according to the basic structure of the atmospheric wind field,a combined wind field model is established to superpose over the parafoil model.Then the overlay model is used to analyze the influence of wind speed on the flight path of the parachute.Considering the deviation for flight trajectory and the ideal one,the calculation scheme which combined with the deviation of position and heading information is designed.Also,the trajectory tracking controller is built.The algorithm for solving each deviation and the tracking effect of PID control algorithm are analyzed in the simulation part.Finally,in order to research the parafoil operation characteristic and to verify the control algorithm,the parafoil semi physical simulation platform is designed based on the steady-state model of four degrees of freedom,and the underlying driver programs are written is designed based on write device drivers,the movement of experimental platform are also writtten and theexercise test of the platform are carried out.The incremental PID controller is designed to control the parafoil homing heading angle,and the effectiveness of the control algorithm are verified by using this platform.The study in this paper provides the theoretical basis for the design of control scheme for parafoil homing.At the same time,it provides a new platform for experimental verification of parafoil control algorithm.