TRAJECTORY BASED 3D FRAGMENT TRACKING IN HYPERVELOCITY IMPACT EXPERIMENTS
Keywords: Hypervelocity impact, Space debris, Fragmentation, Particle tracking, Trajectory fitting, Stereo matching
Abstract. Collisions between space debris and satellites in Earth’s orbits are not only catastrophic to the satellite, but also create thousands of new fragments, exacerbating the space debris problem. One challenge in understanding the space debris environment is the lack of data on fragmentation and breakup caused by hypervelocity impacts. In this paper, we present an experimental measurement technique capable of recording 3D position and velocity data of fragments produced by hypervelocity impact experiments in the lab. The experimental setup uses stereo high-speed cameras to record debris fragments generated by a hypervelocity impact. Fragments are identified and tracked by searching along trajectory lines and outliers are filtered in 4D space (3D + time) with RANSAC. The method is demonstrated on a hypervelocity impact experiment at 3.2 km/s and fragment velocities and positions are measured. The results demonstrate that the method is very robust in its ability to identify and track fragments from the low resolution and noisy images typical of high-speed recording.