A reliable algorithm of rock detection and avoidance for safe spacecraft landing

A reliable algorithm of rock detection and avoidance for soft landing based on CCD landing camera is presented. Firstly, the image of landing zone is fast processed using multi-resolution analysis technique. The rocks of landing zone are detected reliably on the basis of lighting character. Secondly, the rocks detected are recognized and indexed in terms of unsupervised clustering algorithm. The topological diagram of rocks distributed on the landing zone is designed. Thirdly, the true hazard area of the landing zone is computed by the height from laser altimeter and the inner parameters of landing camera. Then the safe landing site selected is demanded to satisfy the safe bound of lander and exploration task. Finally, the safe avoidance strategy of lander is generated, which guides and controls the lander to maneuver to the new and safe site. Craters on the asteroid´s surface are the most importance navigation landmarks on the phase of orbiting exploration.