Static Friction in a Cable-Driven Transmission—Modeling and Identification of Load Effects

Abstract

Although many friction models have been developed by various researchers over the years, a general model does not exist yet. In this article, we present the work that was developed to identify and propose an empirical model that represents the behavior of friction in a cable-driven transmission. We designed and built a test bench that allowed us to study the incidence of friction as evidenced by the type of cable thread, the dimensions of the pulley and the capstan and the application of an external load for pulley-cable type transmissions in a variety of configurations. The results obtained show a marked influence of the external load on friction behavior. Based on these results, we propose a friction model that involves the external load and the transmission ratio. During the validation of the model, it was found that the proposed model reproduced the friction behavior better than the LuGre model, obtaining errors up to 44% lower, mainly for high loads and low speeds.