Research On Structure Optimization And Autonomous Flight Control Of Bird-like Flapping-wing Robot

Flapping-wing robots(FWRs)have become a current research hotspot due to their excellent flight performance and broad application prospects,especially bird-like FWRs with a certain load capacity.In recent years,researchers have developed a variety of bionic FWRs,but there is still a huge gap in flight performance and efficiency compared with flying animals in nature.In addition,the wind tunnel used for the performance test of the FWR has the disadvantages of high test cost and complex test process.In order to improve the flight performance of the bird-like FWR,this paper has conducted research from three aspects: wing structure optimization,performance test optimization platform design,and flight control system design.An experimental prototype system is also developed to carry out experimental research.The main research contents include:Firstly,this paper analyzes and studies the flight mechanism of birds,and on this basis,takes the weight and aerodynamic performance of the wings as the optimization goals,and designs the structural optimization scheme of the FWR's wings.The aerodynamic model of the wing was established,and the simulation analysis of the influence of the plane shape and flexibility of the wing on the aerodynamics of the flapping wing was completed using MATLAB.The simulation results verified the effectiveness of the model.Based on the simulation results,wings with different flexibility,plane shapes,and airfoils were designed for experimental testing and verification research.Secondly,in response to the requirements for the performance test and parameter optimization of the FWR,this paper proposes a spiral arms flapping wing robot performance testing optimization method,designed the wing deformation detection method based on binocular vision system,completed the test platform design and software and hardware system design,and the statics and dynamics modeling and simulation analysis.The platform can simulate the relative incoming flow of different speeds,and can simultaneously detect the lift,thrust,and wing deformation of the FWR.It has the advantages of simple structure and convenient use.It can be used for the performance test and rapid iteration optimization of the FWR.In addition,the platform can also be used to qualitatively and quantitatively test the flight control parameters and attitude adjustment parameters of the FWR,such as the angle of attack,flapping frequency,flight speed,tail swing angle,etc.And the law of their influences on its autonomous flight which lays the foundation for autonomous flight control.Thirdly,on the basis of the research on the wing optimization and flight performance of the birdlike FWR,the kinematics and dynamics modeling and analysis of the robot flight are carried out in this paper,and the attitude representation method of the robot in different coordinate systems and the force situation in the flight process are obtained.A multi-posture sensor fusion algorithm based on Kalman filter is designed,which can accurately calculate the current posture data.On this basis,the study of flight control methods was carried out.Based on the PID automatic control algorithm,the robot's attitude self-stabilization flight method was designed;the flight control hardware system was built and the autonomous flight control software design was completed.Finally,the production of a variety of wings was completed,and the prototype and performance test optimization experimental platform were built,and the performance test and deformation detection of the wings were completed.The results showed that the moderately flexible butterfly wing has the best aerodynamic performance.Test experiments on the influence of angle of attack,flapping frequency,and relative flow velocity of the wing on aerodynamic force were also carried out.The results showed that the increase in the angle of attack of the wing is conducive to the generation of lift,but not conducive to the generation of thrust;the increase of the flapping frequency will significantly increase the average lift and thrust;the greater the relative incoming flow velocity,the greater the lift,when the flutter frequency is too low,the increase in the relative flow velocity will cause the drag increase to be greater than the thrust increase,resulting in a negative increase in the average net thrust.On the basis of the performance test,the robot prototype with the best butterflyshaped wing was used for indoor and outdoor flight tests,the experimental results showed that the designed flight control system can enable the robot to achieve self-stabilized flight and some maneuvers.The action achieved the desired goal of this work.