Design Of Flapping Wing Micro Air Vehicle And Study On Low-noise Flapping Wing

The Flapping Wing Micro Air Vehicle is a new type of aircraft that uses natural flying animals as a biomimetic prototype.It has the advantages of light weight,small size,high concealment and low noise.It can accomplish the tasks that the existing fixedwing and rotorcraft cannot accomplish.FWMAVs have great application prospects in the field of military and civilian.Based on the analysis of the movement patterns and physical characteristics of birds and insects,the motion patterns and basic motion parameters of the flapping mechanism are determined.The design of the flapping mechanism adopts the 3D rod structure in which the sliding pair and the rotating pair are combined to obtain a large performance benefit with a small mass.By establishing the corresponding mathematical model of the flapping,it is verified whether the flapping mechanism can achieve the "0" wingtip motion trajectory.Subsequently,based on the flapping mechanism,the design of the transmission system and flapping wings was derivatively designed,and the whole structure design of the flapping prototype was completed.For the developed flapping wing aircraft model,the aerodynamic characteristics were simulated by numerical calculation method,and the aerodynamic force was estimated.On the basis of the traditional flapping wings,the goal of developing a new low-noise flapping wing is proposed.From the aspect of material properties,the fabrication process of filling high-pressure gas in pressure-heated molten polyethylene film was determined,and the device to make low-noise flapping wing was designed and modified to realize the production of flapping wings with air-filled wing veins.The aerodynamic characteristics of the flapping wing prototype and the noise characteristics of the new flapping wing were tested.The effects of flapping frequency,incoming wind speed and angle of attack on thrust and lift are explored.The sound pressure level and the overall sound pressure level of the carbon fiber vein wing and the inflatable film wing were compared.The equivalent sound pressure levels of the two type of wings are explored under different flapping frequencies.