Aerodynamic Characteristics Analysis, Modeling And Control Of Aircraft With Spanwise Morphing

Aircraft with spanwise morphing is a new kind of morphing aircraft which use of the twisted alongthe spanwise to manipulate the aircraft. With the rapid development of science and technology, thetraditional aircrafts can not meet the requirements of modern flying qualities any more. Aircraftswhich able to complete multiple tasks and meet requirements of different flight environment areurgent needed. With the using of wing twist, aircraft morphing along the spanwise can even achieveit’s manipulation without flaps and ailerons. Meeting the requirement of flexible flight characteristicslike a bird, the aircraft morphing along the spanwise is bound to play an important role in the field ofaircrafts in the future.The paper is based on aircraft along the spanwise, the main work to research torsional deformationalong the spanwise including analysis of aerodynamic characteristics of morphing aircraft, systemmodeling of morphing aircraft, and the design and simulation of the control system.First, using the theory of computational fluid dynamics, the numerical modeling of torsionaldeformation of the wing completed, and the aerodynamic parameters of aircraft in different flightMach number and altitude are numerically calculated. The calculated aerodynamic parameters arethen analyzed, and also the relational expression between aerodynamic parameters on the wing andtorsional deformation is obtained by data fitting methods.Then, the equilibrium point parameters are calculated, according to the longitudinal dynamicsequation, and the relational expression between equilibrium point parameters and torsionaldeformation is obtained by fitting methods. The longitudinal small perturbation linear model ofaircraft morphing along the spanwise which also related to torsional deformation is then derivedaccording to small perturbation theory.At last, according to the uncertainty systems theory, the model of aircraft morphing along thespanwise is transformed into a standard uncertain system model. The quadratic optimal state feedbackcontrol law of the uncertainty system is designed with the using of robust optimal control theory.Finally, after the simulation and analysis of the control law, a stable morphing process of aircraftalong the spanwise and a reliable maneuvering characteristic of aircraft morphing are obtained.