Method of improving steering performance robustness utilizing dimensional non-uniformity in tire/wheel

摘要

The invention relates to methods for improving vehicle steering performance and robustness of that performance through control of non-uniformities in the vehicle's tires, wheels and tire/wheel assemblies as a way to overcome the tendency of the steering systems in certain vehicle types to undergo "steering performance loss." While minimizing lateral force variations (e.g., couple imbalance), a controlled amount of radial and/or tangential force variation is induced in one or more tire/wheel assemblies by means of mass non-uniformity, dimensional non-uniformity, and/or stiffness non-uniformity. For dimensional non-uniformity, the preferred method comprises imparting a controlled amount of dimensional non-uniformity (preferably radial runout) to the tire and/or the wheel in at least one of the tire/wheel assemblies, followed by statically and dynamically balancing all of the vehicle's tire/wheel assemblies. All tire non-uniformities imparted according to the invention are preferably distributed meridionally symmetrically about the equatorial plane of the tire, so as to induce tangential and/or radial force variations but not lateral force variations. Similarly, wheel non-uniformities must be symmetric about the equatorial plane of the wheel. Beneficial tangential and/or radial force variations will result from the operation of tire/wheel assemblies prepared according to the invention, even if the tire/wheel assemblies are balanced by weights added to the wheel. Synergistic beneficial effects result from combinations of the various forms of beneficial mass, stiffness, and dimensional non-uniformity.