Tire Force and Terrain Disturbance Measurements During Turning Maneuvers
Shoop, S.A.; Coutermarsh, B.; Ayers, P.; Anderson, A.; Affleck, R.
Transactions of the Asabe 51(6): 1869-1878
A proof-of-concept study to link vehicle performance measures to associated terrain disturbance was performed with the intent to improve terrain impact prediction methods. Field tests to assess terrain disturbance during turning maneuvers were completed on dry and wet, grassy fields and slopes in northern Vermont. The vehicle tests consisted of a series of spiral maneuvers at two speeds, and serpentine maneuvers on slopes, to comprise a range of turning radii, upslope and downslope turns, and velocity. The CRREL instrumented vehicle (CIV) and a military high-mobility multipurpose wheeled vehicle (HMMWV) were instrumented to measure linear accelerations, angular and linear velocity, wheel forces, speeds, and location. The terrain was fully characterized for soil type, wetness, shear strength, and vegetation cover prior to testing. The disturbance created by the vehicle was measured using the cumulative impact width method based on disturbed width and impact severity. Results show increased disturbance for the wetter soil, but generally the impacts were low because of sufficient terrain strength for these two vehicles. Nonetheless, correlations were found between the measured horizontal forces, accelerations and yaw rates, and the terrain disturbance; most significantly, increased lateral tire-terrain interface forces resulted in increased cumulative impact width. Additionally, the vehicle lateral force, accerlation, and yaw rate that were directly measured are comparable with those calculated from the global positioning system (GPS) data, illustrating the potential of the much simpler measurements for this purpose.