Mechanisms Design And Stability Research Of "I-shaped" Tilt-rotor Aircraft

With the increasing complexity of the working environment and type of small unmanned aerial vehicles,tilt-rotor aircraft with vertical take-off and high-speed cruising capabilities are beginning to take on more and more missions.In view of the fact that the current tilt-rotor aircraft cannot meet the requirements of load and span design at the same time,the paper proposes a tilt-rotor aircraft with four tilting rotors,double-row wings and no movable tail.A suitable type of tilt-rotor aircraft is designed by means of selection,calculation,modeling,simulation analysis and experimental verification.Firstly,according to the "I-type" layout,the wing and fuselage of the aircraft are selected and designed to determine its technical parameters.For the tilting mechanism,the three tilting mechanisms are analyzed and compared according to the "six sexes" of the product.After selection,check the key components of the tilting mechanism.The FLUENT software was used to study the influence of the slip flow generated by the rotor at different tilt angles on the aerodynamic characteristics of the wing.The simulation results show that the area of the slip generated by the rotor affects the single wing by 33.5%,and as the tilt angle increases,the resulting slipstream will reduce the lift of the wing.Secondly,the tilt-rotor aircraft has instability hazard during the tilting transition: when the aircraft transitions from hovering to cruising,the aircraft adopts the cruising mode to obtain the cruising speed,and the short position quickly tilts to solve the stability problem;The transition of the cruise to the stable suspension tilting requires the rotation angle of the rotor to match the flight speed.The Matlab software is used to analyze the mathematical model of the aircraft from the cruise to the hovering stage.The simulation results show that the flight from the cruise to the hover transition phase is 15.5s,and the tilting process is stable.Finally,an external field test is performed to monitor the real-time flight data of the test machine through the display and to make the flight parameters into a curve.The curve shows that the transition time from the cruise to the hover is 16 s,which is basically consistent with the simulation value;however,the actual flight speed has a certain deviation from the simulated value.The reason is that the ideal experimental environment is quite different from the actual test flight environment.This experiment laid the foundation for subsequent research and product development.