Analysis And Research For Space Debris Collision Probability And Its Threshold

With the expansion of the human's activity in the outer space, the population of the space debris has grown greatly. Efficient protecting to the spacecrafts in orbit must be down as the impacting risk become serious increasingly. Space Debris Collision Avoidance (SDCA) is the only strategy to reduce the risk of collision, when the dimension of space debris is lager than 10 cm. The decision whether the avoiding maneuver is necessary depends on the analysis of conjunction, the rigorous calculation and assessment of collision risk between spacecraft and debris and compare to the collision criterion. Based on the analysis of covariance, the collision probability is an efficient criterion for SDCA.Presently the framework of Space Debris Collision Avoidance System (SDCAS) has already completed, including kinematical data acquisition, extrapolation of orbit, prediction of conjunction, analysis of covariance, collision probability calculation and orbit maneuver etc. The criterion and process of SDCA which is relative to the engineering has also been explored.Some problems of collision probability and its threshold are discussed in this paper. Base on SDCA, the method for collision probability calculation was researched further more, with collision probability when the relative motion is non-linear and maximum probability was researched, which made the result of collision probability more credible. The method for threshold of collision probability was also analyzed base on the flux of space debris, which supplied criterion of SDCAS.Now, the max probability and the threshold of collision probability has being used in SDCAS, and working in many engineering system.