Friction and Stick-Slip Phenomena in Steering System - Modeling and Simulation Studies

The article is the third one of series of the authors' SAE Papers (other two: 2002-01-0619, 2005-01-1261) concerning modeling and simulation studies of strong non-linear processes in a car steering system. Here, attention is concentrated on the stick-slip phenomenon caused by the dry friction. The studies focus on the influence of different kinds of friction force characteristics (from Coulomb-type to Stribeck-type) on the steering system dynamics. We present mathematical models and simulation studies of the stick-slip phenomena in a typical steering mechanism. The simulations concern the open loop tests (sinusoidal input and combination of ISO maneuvers) and provide materials for a sensitivity analysis (different friction models and vehicle motion conditions). The presented models, example simulation results and conclusions may be interesting not only for specialists working on the car steering system problems but also for researchers working on the non-linear dynamics in multi-body systems.