Keywords: Helmert transform, continuous dynamic programming, 2DCDP, hypervelocity impact fragments, fragment tracking, spotting recognition, monotonous contiguity, motion analysis, collision destruction
Automatic tracking of impact fragments
In general, it is difficult to understand how the object was before collision and what had happened during collision after a collision has destroyed them. The motion analysis of the collision destruction phenomenon is extremely important as a help of the total analysis of the destruction process and the automation of the motion analysis of impact fragments has been requested in the field of hypervelocity impact experiments. Some fragments were automatically tracked on images cut from an impact experiment moving picture. A combination method of the two dimensional continuous dynamic programming (2DCDP) method proposed by Oka (1998) and the Helmert transform is proposed and applied in tracking fragments. After some improvements, tracking of fragments was performed sufficiently and the effectiveness of this method was confirmed. As a result, physical quantities of impact fragments such as translation velocities, rotation velocities and so on were derived from the analysis.