Synthesis of tire equations for use in shimmy and other dynamic studies

.4 system of transfer functions relating the cornering force and aligning torque of a rolling pneumatic tire to its yaw angle and lateral displacement are developed from experimental and theoretical frequency response curves. These transfer functions consist of ratios of polynomials in the Laplaciari variable s, which lead to a system of linear constant coefficient differential equations. The resulting equations have the advantage of both simplicity and accuracy and are ideally suited for use in dynamical analysis such as the study of wheel shimmy phenomena. These differential equations, along with the corresponding experimental frequency response curves, are compared with those derived from the widely used Moreland tire theory. This comparison reveals a number of inadequacies in the Moreland theory.