Mathematical Model And Autonomous Flight Control Of Soft-Wing UAV

Soft-wing Unmanned Aerial Vehicle(soft-wing UAV)is a new kind of UAV,which is composed of soft parafoil and powered vehicle hanged by ropes.Benefit from its simple structure,higher flight load ratio and less demands for takeoff and landing,soft-wing UAV has some incomparable advantages over other kinds of aircrafts in certain tasks execution,that will also makes it have a wide range of applications either in the military or civilian fields.However,because of its soft characteristics in aerodynamics and non-rigid connection between the parafoil and powered vehicle,soft-wing UAV possesses apparent mass,flexible structure and inside relative motions,which are the difficulties in the further research of soft-wing UAV.At present,foreign researchers have achieved some progress in mathematical modeling and actual flight tests of soft-wing UAV.However,the research on soft-wing UAV in China has just developed for a couple of years and there is a big gap to be caught up with other developed countries.Besides,there are a lot of problems needed to be dealt with in further deep study.Aiming at the self-developed soft-wing UAV system by Shenyang Institute of Automation Chinese Academy of Sciences,the mathematical model was built by using'Grey box' modeling method based on system identification.The PID flight control algorithm was designed based on mathematical model.The paper's work mainly includes 4 parts.First,the 6 DOF motion equations of Soft-Wing UAV was built by mechanism method,and the transfer function model was obtained through the linearization and decoupling,which provided priori knowledge for identification.Secondly,the identification experiment was designed,which is included design of input signal,flight data acquisition,the pretreatment of flight data.Then,based on the priori knowledge provided by mechanism model,the mathematical model was built by using least square identification algorithm method,and used other flight data to model cross validation.At last,based on mathematical model by identification,using the PID control method,an autonomous flight controller for soft-wing UAV was designed.Besides,the simple following trajectory points flight was also accomplished to validate the validity of model.