Research On Parafoil Modeling And Control Technology Of Parafoil Airdrop System

Because of the gliding characteristics and control characteristics, parafoil system has become a hotspot in airdrop. Recently the study of parafoil inland lagged behind greatly. In this thesis, the problems were analyzed thoroughly in method of theoretical and numerical simulation, including parafoil dynamics, trajectory design and trajectory following.In this paper, the 6DOF nonlinear mathematical model of parafoil system and the simulation model of flight exercise were designed. The basic dynamic properties of the system, and some geometric parameters'effects on the system dynamics were researched and summarized. All those studies would be theoretical bases to working process and control technology researches of parafoil system.In order to realize accurate, safe landing of parafoil system, according to its own maneuverability and basic flight characters, homing strategies of parafoil system were analyzed thoroughly. Then, multiphase homing trajectory of parafoil system was designed. Transfer trajectory optimization to parameter optimization by using of the geometric relationship between trajectory, improve the basic genetic algorithm, and get effective solution by using Improved Adaptive Genetic Algorithms (IAGA), which could efficiently improve convergence speed and avoid the occurrence of premature.Two method were used to research control technology of parafoil airdrop system. One method is to design track controller directly, according to the linear time-variable error equations of parafoil system, and fuzzy adaptive PID controller was designed. Another method is traditional trajectory control of aircraft, which divided the whole controller into attitude stabilization inner loop and center of mass motion outer loop, and attitude stabilization inner loop was researched thoroughly by using fuzzy sliding mode control.Finally, in VC++ programming environment, three-dimensional visual software of parafoil airdrop system was developed by using Open Graphics Library (OpenGL) and three-dimensional modeling tool Milkshape 3D.