Aircraft Bird Strike Test The Instantaneous Speed Of The Continuous Test Method Research

Up to now, the current velocity measurement methods can onlygenerally be used to determine the average velocity of a moving objectbetween two points. The continuous measurement method of theinstantaneous velocity has not been developed and aPplied enough yetover the coufltry from author's knowledge. In this papef, a non-contactvelocity measurement system that can determine the instantaneousvelocity continuously with low-cost, high-accuracy, and good-reliability,is described. A sheet of laser beam emitted from the optical system isprogressively blocked and unblocked by the moving bird-shell. Thecorresponding variation of olltput voltage due to the change of total laserintensity is measured by a photo detector. A displacement-time curvecan be obtained by calibrating the re1ationship between block positionand output voltage of the photo detector. Through the use of simplemathematical operation, the bird-shell velocity and acceleration historiescan be determined, and therefore the bird-shell instantaneous velocity atany points within the measurement range can be obtained. Finally theaccuracy of this system has been analyzed. The comParison test resultsshow that the error of the measurement is not exceeded 1%. Thismethod can also be aPp1ied to a wide range of engineering materialimpact research and other civil areas.