Indoor or laboratory testing of tire tread wear offers many advantages over vehicle fleet testing. Advances in test equipment capabilities and the technologies for defining and simulating meaningful tire loading histories has made indoor tread wear testing a reality. Tire loading histories are influenced by vehicle characteristics, wear course and driving style, and tire stiffnesses. Methods for independently characterizing each of these are reviewed. A simulation technique, TS-Sim, is also described that combines specific vehicle, course and tire characterizations to create a tire load history.
The vehicle characterization is critical to the process since both wear rate and various forms of uneven and irregular wear are strongly dependent on vehicle suspension/steering characteristics and on dynamic load transfer behavior. The characterization process involves mapping the vehicle over a practical range of acceleration, deceleration and cornering maneuvers. This mapping can be carried out by use of a computational vehicle model or by experimental testing of an actual vehicle. The proposed vehicle characterization method distinctly captures each wheel position response, showing differences in driven and non-driven positions, steered and non-steered positions, as well as effects of suspension type, alignment, stiffness and kinematic properties. Improvements and recent advances in the modeling method are reviewed.
Vehicle modeling with commercially available software has progressed to the point that it can be used in place of an actual vehicle to provide the necessary characterization. Examples of how this is used and comparisons to actual vehicle measurements are included. Altering of vehicle characteristics can be done with the model and used to determine the effect on tire wear through this process. Tire wear results are shown.