Computer Analysis of Forklift Truck Stability when Operating on Side Slopes under Near Static Conditions

摘要

Two basic methods are used to obtain equations for determining the critical slope for a vehicle. These are: (1) the action line method, in which the combined center of gravity (CCG) for the vehicle is determined, and the critical slope obtained by finding the sideslope upon which the vehicle must be resting so that the CCG is directly over the action line formed by two downhill points of support of the vehicle, and (2) the wheel load method, in which the loads on the four tires are examined under all possible sideslope conditions to determine the minimum slope for which the vehicle will be in an unstable condition. The report includes a computer program using the equations derived form the two methods for deterimining critical slopes. This program allows the vehicle parameters such as type of steer, suspension, frame, weights, and dimensions, to be varied, and for each set of parameters provides the maximum slope on which the vehicle can rest in a stable condition. The program also shows the orientation of the vehicle corresponding to this critical slope. The computer program follows the wheel load method for vehicles with midrange oscillation; i.e., vehicles in which the front part can rotate relative to the rear part about a longitudinal axis, with the oscillation joint located somwhere between the front and rear axles. For all other types of vehicles, it uses the action line method. (Author)