Implementation of measurement of aircraft fault protector performance based on virtual instrument

Aircraft fault protector must be tested in the lab by simulating its working condition before using. This paper presents a measuring system of aircraft fault protector performance based on virtual instrument. In order to measure velocity and acceleration accurately, a hardware timer and buffered period measurement method are employed to acquisition the pulses of encoder periodically. With the first and second order differential for position value, velocity and acceleration are retrieved. Wavelet noise-reduction method is used to reduce the noise within measurement data through setting of soft and hard thresholds for different signals. The features of saving data and drawing curves automatically make the operation convenient. Practical test results show that high precise measurement of aircraft fault protector parameters can be achieved and the system has a good stability and better applicability.