Analysis of belt transmissions capabilities using the brush model

The mechanics of power transmission is usually modeled by two different theories: the creep theory and the shear theory. Recently, the authors introduced an alternative theory based on the brush model, which allows to compute the tangential stress distribution along the winding arc of pulleys. The brush model is able to predict the speed loss along the driving and driven pulley as a function of the transmission parameters (e.g. pre-load, friction, pulley radii etc.) and the operating parameters (i.e. angular speed and resistant torque). In addition, the energy efficiency of the system is obtained by knowing the speed loss and the energy dissipation; this contribution can be subdivided into energy loss due to friction and energy loss due to the non-recoverable elastic deformation of the bristle. In the present paper, using the previously developed model, a sensitivity analysis aimed at mapping the transmission capabilities as a function of geometry and operating parameters is proposed. These results, given as look-up table (or contour plot), are very important in mechanical systems simulation (e.g. real-time systems, hardware in the loop systems) since they allow to introduce the phenomenological behavior of the pulley-belt transmission without introducing complex models in the simulation.