| Future aircraft design will face the challenge of airspace,speed field continues to expand,the adaptability requirements continue to improve,thus the traditional fixed-shaped wing is difficult to meet in a complex,changing flight conditions to ensure high aerodynamic performance requirements;and the technology of morphing wing can improve aircraft aerodynamic efficiency,expand the flight envelope to provide new ideas and new methods.Based on this research background,this paper presents a design scheme of variable camber wing driven by piezoelectric actuator,and focuses on the theoretical research and experimental verification around the design of the morphing wing system.The main contents of the study are as follows:(1)Structural design and performance analysis of variable camber wing.In this paper,the whole structure of the variable camber wing driven by MFC is designed,and the morphing wing section is made by 3D printing technology;the simulation analysis of structural deformation performance of the variable camber wing is carried out by using the finite element method combined with piezoelectric driven load comparison means;Furthermore,the fluid/structure/control coupling analysis platform of piezoelectric drive variable camber wing based on MATLAB,X-FOIL and ABAQUS is built,and the flow-solid coupling simulation analysis is carried out on the morphing wing.The simulation results show that the variable camber wing has good shape control effect,and it can realize the effective adjustment of the aerodynamic characteristics of the wing.(2)Piezoelectric fiber composite actuator MFC drive performance analysis and hysteresis and creep characteristic inverse compensation.The problems caused by the inherent hysteresis and creep nonlinearity of the piezoelectric material on the structure deformation control,the PI(Prandtl-Ishlinskii)hysteresis model and log(t)creep model are used to refine the modeling of MFC hysteresis and creep nonlinearity.Based on this,the inverse model is derived to realize the feedforward and inverse compensation controller design;taking the MFC drive Cantilever aluminum plate as an example,the effectiveness of hysteresis and creep compensation method and the MFC drive performance and control precision are tested.The experimental results show that the inverse compensation model can effectively overcome the nonlinear characteristics of the MFC driver,and the MFC controller can achieve high-precision dynamic deformation control effect of the controlled structure.(3)Design and experimental study of piezoelectric drive variable camber wing control system.In order to verify the deformation control effect of the variable camber Wing,an MFC-driven wing deformation control experimental platform was constructed.The design of variable camber wing open and closed-loop control system with hysteresis and creep compensation is completed;the control system is embedded through MATLAB and LabVIEW joint programming method,and the ground experiment of variable camber wing shape control is carried out to verify the feasibility and effectiveness of the proposed control method.(4)Wind tunnel experiment and aerodynamic analysis of variable camber wing.To test the aerodynamic carrying capacity of the morphing wing and the driving performance of the MFC under aerodynamic load,a low-speed wind tunnel test was performed on the morphing wing.During the experiment,the flow field structure of aerofoil was obtained by using smoke line tracer.At the same time,the aerodynamic characteristics of the wing deformation changes brought by the use of CFD means to analyze.The experimental results show that the variable camber wing system has good deformation control effect under the real aerodynamic load,and can effectively control the flow field structure and aerodynamic characteristics. |
