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A vehicle trajectory simulation called VTS has been developed as an aid for reconstruction of automobile accidents. The two dimensional vehicle has longitudinal, lateral and yaw degrees of freedom, a point mass at the center of gravity) yaw inertia about the center of gravity and four contact points (“tires”) which can be arbitrarily positioned. No collision or aerodynamic forces are modeled. The traction surface is represented as a flat plane with a specified nominal friction coefficient. Several quadrilateral “patches” may be applied to the surface to change the friction coefficient in specific regions. User vehicle control consists of timewise tables for steering angle and traction coefficient for each of the four wheels. When used individually or in conjunction with other computer modules, VTS provides a convenient, accurate modular tool for trajectory simulation.

This paper describes the mechanics of using a desktop (microcomputer) workstation to produce a computer-generated video (television) animation of a ground vehicle moving on an arbitrary terrain surface. The results show that desktop engineering video animation is a viable tool for visualizing simulated three dimensional motions of ground vehicles over off-highway terrain. The approach taken was to use an existing commercial broadcast video animation code (TOPAS) to produce animated vehicle motion from time histories obtained by numerical dynamic simulation using the HVOSM code. The test cases used to verify the techniques described in this paper did not represent actual vehicles or terrain surfaces.