Abstract
Next to gear transmissions, belt transmissions are the most common mechanical transmissions. Belt design and development is based on application tests of belts. This is a need for theory development, designs support systems and would enable simulation for prediction and optimization of fatigue life. The performance of automotive power transmission belts is determined by the selection of the belt type and by the belt material properties. The nature of the materials and the environment in which the belt operates means that these properties will change throughout the lifetime of the belt. This paper describes the failure modes for automotive belts and discusses how belt material and environment changes can be taken into account in the prediction of automotive belt life.