Aerodynamic Analysis And Prototype Design Of Bionic Flapping Wing Driven By Dielectric Elastomers

With the development of micro air vehicle(MAV),a kind of MAV driven by flapping wing have been attracted in rescue,detection,military and biomimetic investigation due to its small size,lightweight and strong concealment.At present,most flapping wings use a motor as driver,and a large number of linkage mechanisms use to convert the motor rotation into a flapping action.However,birds in nature rely on their own muscle and bone structure to fly.From the perspective of bionics,the motor-driven flapping wing is very different from the birds in nature,and the transmission construction increases the complexity of the flapping machine.Therefore,in this paper we intend to use a new type of driving method to develop the flapping wing robot,so as to simulate the process of the muscles driving the wings during flight.In smart materials,the dielectric elastomer has the closest driving performance to natural muscles.It has many advantages such as high energy density,responsiveness,flexible drive,etc.Therefore,in this paper we attempts to design a new type of flapping wing with dielectric elastomer as the driver.The main research contents in this paper are as follows:In this paper,the dielectric elastomer-driven joints are optimized in structure and process to make the wings generate high-frequency flutter.The improvement of the joints includes improving the drive life,increasing driving ability,reducing quality and improving repeatability.By analyzing the performance parameters of the motor-driven flapping machine of different sizes and combining the performance of the optimized dielectric elastomer driver,the flexible wing structure and size for the flapping wing are determined.Computational fluid dynamics(CFD)method is used to study the influence of the passive deformation of the wing on the aerodynamic forces during the flapping,and conducts selections of the airfoil.We build the aerodynamic equations of the flexible wing,and the lift and thrust generated during the flapping process were solved by Simulink.A three-dimensional simulation model of the flapping wing was established in Fluent,the monitored lift and thrust were compared with the aerodynamic analysis results.And the simulation model is used to optimize the flapping flapping frequency.A small wind tunnel was built according to the size of the flapping machine.In this paper,the configuration of the flapping wing is determined and the production of the flapping wing machine is completed.The flapping force measuring platform and the sensor information acquisition module are built to test and record the lift and thrust of the flapping wing.The lift and thrust data obtained from the flapping wing in the experiment is compared with the simulation and aerodynamic analysis results,and the error between the dynamic analysis result and the experimental data is analyzed.