Commercial Vehicle – Development and Validation of Vehicle Dynamics Model to aid in Handling Evaluation

When commercial vehicles have less than ideal lateral dynamics traveling at high speeds, those dynamics can sometimes be a significant factor in serious and fatal accidents that occur. The primary goal of this study was to create a validated vehicle dynamics model to aid in handling evaluations and a validated model that can play an important role in accurately predicting the movement of the vehicle in limit conditions. The model is used to simulate the effect on roll gradient by altering spring stiffnesses and adding a rear stabilizer for a class 6 or class 7 commercial vehicle (CV). Outputs from 4-post Kinematics & Compliance (K&C) tests of a prototype vehicle were used to model the suspension system. The tire model was developed in collaboration with Calspan [1] using physical tire testing. The vehicle masses, inertias and stiffnesses were modelled using IPG TruckMaker for Simulink (TM4SL) [2]. A constant radius turn maneuver was simulated using TM4SL, and MATLAB [3] was used for batch processing of simulation results. Simulation results were then compared to field test results to correlate the model. Once a successful correlation was achieved spring and stabilizer bar stiffness could be altered within IPG and their effects on vehicle handling could be analyzed.