Research On Design And Control Of Flapping-wing Micro Flying Robot

Birds,insects and bats are the typical representatives of flying species in nature.The flapping-wing movement patterns which are used by its are quite different from those of fixed-wing and rotors which can be used by human beings at the present stage.As a result of natural selection,flapping-wing pattern has irreplaceable advantages over others,and has a wide application prospect in many fields.Therefore,the flapping-wing flying robot has become a attractive research direction at this stage,especially the flapping-wing micro fly robot which is based on MEMS.The smaller scale brings it good concealment,flexibility and lower energy consumption.Of course,it also brings more challenges,such as the acquisition of high lift under low Reynolds number,the storage of energy,the realization of control methods and so on.Based on this,this paper carries on research about design and control method of flapping-wing micro fly robot,mainly includes the following contents:Aiming at characteristics of the flapping-wing motion,lift mechanisms of insects was studied and discussed,including added mass,absence of stall,rotational circulation,clapping and fling,wake capture,which provided the theoretical basis for the aerodynamic part involved in the establishment of flying robot system model.The results show that the flapping-wing micro flying robot will exhibit high-frequency flapping-wing motion to obtain relatively stable lift at low Reynolds number.Besides the main flapping motion,the wing motion also includes torsional motion.It ensures that the angle of attack is always positive.According to the research conclusion of lift mechanisms,the thoracic cavity structure of Diptera insects is selected as the original model of flapping-wing micro flying robot,and its motion characteristics are defined as high frequency and two degrees of freedom for each wing.Firstly,the structure of the thoracic cavity is simplified and the motion model of the two-dimensional flying robot is obtained.Then the motion input mode of the system is selected to determine the kinematic relationship between wing and actuator.Then,the aerodynamic model of the wing is established by the blade element method,and the trajectory of each degree of freedom is described.Finally,the multi-rigid body time-varying model of flapping-wing micro flying robot is established based on the Newton-Euler equation which includes the inertia effect of the wing,and the approximate time-invariant "average system" is obtained by averaging method.The simulation results show that the averaging method is reasonable.The design method of flapping-wing micro flying robot is based on multi-rigid body time-varying model.Because of the coupling relationship of design parameters,the calculation is huge and complex.Therefore,the linear model for design is obtained to optimize the design of subsystems of the flying robot under reasonable assumptions.The wing design method is based on the results of bionic research,and its trailing edge contour is approximated to beta distribution.The parameters of the transmission mechanism are optimized by using the risk function between the real and the linear transmission relationship.The actuator adopts the method of electromagnetic driving.Under the condition of satisfying the lift required for flight,the relevant parameters of the actuator are determined by satisfying the lift required for flight.Combining with structural parameters,the selection method about trajectory parameters of wing motion is discussed.It is considered that the higher lift and attitude moment can be obtained when the motion frequency is near 100 Hz.Finally,the rationality of the design method is proved by Adams.A sliding mode adaptive control algorithm based on Lyapunov's stability theory is proposed to complete the attitude control of flapping-wing micro flying robot.The design of the controller is based on sliding mode control to suppress the tracking error of the system.In combination with the adaptive control method,the model parameters that can not be accurately calculated are approached in real time,and the chattering problem caused by the switching function in traditional sliding mode control is alleviated.Simulink simulation results show that the sliding mode adaptive control algorithm is superior to the traditional sliding mode control,and has good robustness in the influence of airflow.