A computer-implemented method for vehicle impact analysis including obtaining a B-Rep representing an outer surface of a vehicle, the B-Rep having faces and obtaining a radius value for a contact sphere. The method also includes determining one or more two-point-contact curves of the B-Rep for the radius value. The determining includes, for each respective two-point-contact curve, solving a respective differential equation based on the B-Rep. The method forms an improved solution for vehicle impact analysis.