Off-road Vehicle Rollover and Field Testing of Stability Index

Off-road vehicles are often operated in unstable situations and on rough terrainwhere operators may be subjected to high-risk conditions. Tractor stability and thereduction of injuries related to tractor rollovers are areas that need to be addressed.This article presents typical tractor rollover tests and analyzes tractor stability interms of the stability index developed by authors. Three radio-controlled tractors wereused to complete the tests. Tractors dynamic state variables, such as roll and pitchangles, roll and pitch velocities, and ground speed, were recorded by the measuringsystem of tractor stability developed by authors, concurrently the image from videotapewas used to identify the stability status of the tractors.The effect of velocity, ramp height, slope, and turning radius on tractor stability wasstudied. Rotation velocities can also significantly contribute to tractor rollover. Theresults indicate the validity of the stability index model.