Comparison of Three and Four Wheeled ATVs Over a Bump Profile

Several new mathematical models of a rider ATV system are developed. These new models allow the ATV to have either three or four wheels, the rider to be placed at any orientation relative to the vehicle, and the ATVs wheels to rotate. These models are used to investigate the simulated motion of an ATV system over a bump profile. For each model, overturning stability plots are generated as a function of the rider's side lean angle and the vehicle's initial velocity. These results show that the four-wheeled ATV system is more stable than the three-wheeled ATV system over the bump profile. In addition, the inclusion of wheel rotation only slightly improves the overturning stability of the ATV system and this improvement occurs only at high vehicle speeds.