Abstract
A group of 12 staged and instrumented car collisions was conducted in the mid 1970's for the national highway traffic safety administration. These were two- vehicle collisions with a variety of initial speeds, vehicle orientations, and vehicle size mixes. Initial speeds were controlled and velocity components including angular velocities at separation, were measured. Inclusion of a moment, and introduction of a moment coefficient of restitution, allows the formulation of a planar collision model consisting of six algebraic equations relating the six velocity components of the two vehicles to their six final velocity components.