Description / Abstract: Introduction

Note: Nothing in this standard supercedes applicable laws and regulations.

Note: In the event of conflict between the English and domestic language, the English language shall take precedence.

Purpose. This standard is written to describe, in general terms, all tests required for SWIFT tire modeling input, as specifically run on the Flat-Trac equipment (LTRe, CT+, Flat-Trac equipment, or equivalent). (Model designation available from MTS Systems Corporation.) The data generated by this test is used to create SWIFT models for vehicle simulations of ride performance.

Applicability. It is restricted to controlled laboratory tests on passenger and light truck tires.

Remarks.

The tire Force and Moment (FM), dynamic cleat, and other properties, addressed in this test, are important to various vehicle simulation groups, since these tire properties will dictate to a great extent the vehicle’s response to specific control inputs.

Tire properties addressed in this test are dependent upon almost every physical characteristic of a tire including the tire structure, compounds, and tread design. Tire properties addressed in this test are also dependent upon the usage environment such as the load, inflation pressure, rim width, speed, state of wear, surface texture, temperatures, tire age, storage history, and usage history. This is pointed out to emphasize the need to be diligent in the selection of test tires, their storage conditions, and attention to detail in following good test practices outlined in this procedure.

The quantification of tire properties addressed in this test requires the measurement of the net resultant forces and moments from stresses within the tire footprint area. This implies the footprint dynamics on the measurement equipment must be similar to those experienced under actual vehicle operation. Therefore, a flat surface machine using a textured surface is required.