Wind-Tunnel Experiment And Data Process For Samll-Scale Autonomous Helicopter

Small-scale autonomous helicopter has a broad application prospect for its characteristics of small size, strong maneuverability, ability of vertical taking-off and landing and so on. However, the highly underdamped characteristic of small-scale helicopter makes it have poor wind resistant ability. Small-scale autonomous helicopter usually works in outdoor environments, so there is a practical significance at research on wind resistance of small-scale autonomous helicopter under gust disturbance.Firstly, this thesis gives a practical scheme of wind tunnel experiment. The experiment platform is mounted on the six-component balance platform system in the Low-Speed-Open-Wind-Tunnel of Nanjing University of Aeronautics and Astronautics. The experiment platform, which has good ability of stiffness and accuracy, is made of a whole block of hard aluminum through electrical discharge machining and drilling technical means. The experiment contains many experimental statuses with different forward angles, different wind directions and different wind speeds. Forces and torques applied on the helicopter model are measured during the experiment process in each experimental status.Secondly, this thesis processes and analyzes the data collected during the experiment. At stage of the experiment data pre-process, the experiment data has been verified on theory, so it is proved to be effective.In order to get the high-order polynomial function relationship between the forces and torques, which are the outputs, lateral and longitudinal cyclic pitch and collective pitch, which are the inputs, the least square method is used to fit the output curve of experiment data. On the basis of these, taking wind variable as a coupled input, the high-order polynomial function relationship, of which the wind variable, lateral cyclic pitch, collective pitch are the arguments, forces and torques are the dependent variables, is obtained.Finally, we get the conclusion that the polynomial function relationship between each input independent variable and each output variable can be found. The flight controller of small-scale autonomous helicopter designed based on this research will have better performace of wind resistance.