Development of a Trailer Axle Friction/Wear Tester

Although research on tire-road contact mechanics has continued for several years and has resulted in vast number of papers, most models are based on theories that contain many assumptions. Accurate measurement of tire friction and wear in controlled conditions can reveal answers to various assumptions and problems related to tire-road contact mechanics. Equipped with force hub, servo motor, air spring and other sensors, the Trailer Axle Tire Friction/Wear Tester can provide accurate measurement of real-time tire friction and wear under different normal loads, slip ratios, velocities, tire pressures, and dry/wet conditions.

In this paper, the design and development of the axle, which replaces the existing axle of a three-axle trailer alongside the data collection and processing, are discussed. Using the data, support vector machines (SVM) and Kalman filter algorithms are developed and utilized to construct tire wear estimation model. This model describes the mapping relationship between slip ratio, area of contact patch, tire acceleration (measured by a tri-axial accelerometer adhered on tire inner liner), tire pressure, tire load as inputs, and tire weight, tread depth as outputs. Data collected for various tires on the Virginia Tech Transportation Institute (VTTI) Smart Road are used for model development and validation.