New model of random gust acting on aerospace vehicle

Random gust directly influences the structural design and operating performance of an aerospace vehicle. However, the random gust model used for studying the perturbation of the aerospace vehicle has some deficiencies: it can onlycalculate the amplitude value of randomgustwith asingleconfidence degree but cannot calculate the amplitude value with an arbitrary confidence degree according to the performance index. We propose analgorithm for calculating the amplitude value of random gustbased on its frequency-spectral correlation, which can arbitrarily designate the confidence degree. We establish the frequency-spectral model and discrete model of random gust, derive the functions for calculating its amplitude value and project the random gust model to the coordinates of the airframe of aerospace vehicle. The simulation results showthat: the proposed algorithm is accurate and effective, being able to precisely calculate the amplitude value of random gust acting on the aerospace vehicle; it can calculate the amplitude value of random gust with the confidence degrees arbitrarily designated according to different design requirements and operating performances of the aerospace vehicle, providing a good reference for the perturbation design of its control system.