Mathematical Models of Stiffness Nonuniformity and Run-out Effects as Measured on a Low Speed Nonuniformity Machine

Abstract

Abstract Two types of tire nonuniformity seem to be mainly responsible for the radial force variation of a slowly rolling tire as measured on a nonuniformity machine: radial stiffness variation around the structure and roundness nonuniformity, also called run-out. The purpose of this paper is to present mathematical models representing either of these variations. The models assume that the natural frequencies and modes of the uniform tire are available, and expresses the effects of the nonuniformities in terms of these uniform modes. The method presented can be used to distinguish between stiffness and geometric nonuniformities.