Design Ofanaxiallytelescoping Wing Control System And Nonlinear Vibration Experiment Research

Aircraft faces a variety of missions. Different missions require different performanceand layout of the aircraft. With the demand of flight efficiency, mobility and multi-taskingability of aircraft improved, morphing aircrafts have risen a wide range of interests inacademia and the aerospace industry recent years. Morphing aircrafts can change shapesin flight, in order to adapt to complex flight environments and complete various tasks.This quality effectively improves maneuverability and flight performance. Retractablewing is a kind of morphing wing; it can change wing area and aspect ratio to adapt to thechanging environment. The theoretical model of retractable wing is axially movingcantilever beam.In this paper, the transverse vibrations and control problems of axially movingcantilever beam are researched, in order to provide a new direction of the design ofretractable wings.First, The control system is designed by using a STC89C52SCM, an AC servo motorand two margin micro-switches. The STC89C52SCM sends out impulse signal and directsignal to the servo motor by the C language program based on KEIL-C. Extending andrecovering movements of the cantilever beam are achieved by the movement of gear andscrew system driven by the servo motor. The margin micro-switch can stop the cantileverbeam when it reaches the edge.Secondly, the transverse vibrations of cantilever beam through extending andrecovering movement are collected by accelerometer; the data, which are analyzed andprocessed by LMS data acquisition and analysis system, are compared with theoreticalresult.At last, LMS. Impact Testing and Modal Analysis are used to carry on modalexperiment of telescoping wing. Dynamic characteristics of three conditions oftelescoping wing (no-extending, extending400mm, extending600mm) are researched byusing hammering method. Natural frequency and modal of telescoping wing can becalculated.