System Design And Prototype Fabrication Of Simulating Bird Flapping Robot

The bionic flapping robot,as one of the research hotspots of multidisciplinary cross cuttings,which is becoming the main research content of new special aircraft.Although a lot of research has been done on flapping robot at home and abroad,most of them focus only on local studies such as flapping mechanisms or aerodynamics,and the design process of the system's flapping robot is relatively small.The thesis imitates bird flight,carrying put the overall design of the flapping robot,aerodynamic modeling,flapping wing design,prototype fabrication and force platform design,proposing a relative complete design process of flapping robot.The thesis studied the overall design of the flapping robot.For the core drive mechanism of the flapping wing,several different flapping mechanisms such as the front double crank and the front double push rod were compared and analyzed,and the front double crank mechanism was selected.The size of the mechanism was calculated in detail;ADAMS performs simulation analysis on the flutter mechanism as a prerequisite for the prototype design.Based on the leaf element theory method,a mathematical model of aerodynamic analysis suitable for low-frequency flapping wing motion is constructed.The input parameters of the model include:flutter amplitude,flutter frequency,angle of attack and other parameters,and the output is lift,thrust and drag.The model is used to analyze the influence of different input parameters on aerodynamic forces.The results shows,the impact angle change has a greater impact on lift,and the flutter movement has a direct effect on the regulation of thrust.This provides a theoretical basis for the design of the flapping wing prototype.Two types of flapping wings were designed and fabricated: four-link folding wings and passive folding single wing.Both of them mimic the behavioral characteristics of the bird's wing-wing movement,and realize that the wing is folded in the upper stroke to reduce the aerodynamic drag and expand in the lower stroke to increase the aerodynamic lift.According to these two types of flapping wings,the flapping machine was processed separately.A force measurement experimental platform was built to test the mechanical properties of the flapping wing prototype using a one-dimensional force sensor.The experimentally measured lift and thrust is compared with the simulated lift and thrust.The results show that the measured data is basically consistent with the overall trend of the simulation results.The paper also makes a preliminary comparative study on the lift characteristics of three different airfoil types: space-deflected single-wing,passively folded single-wing and four-link folded double-wing.Finally,an outdoor test flight was carried out on a single-stage passive folding flapping machine.