Functional Modelling and Simulation of an Electric Power Assisted Steering - Development of an advanced engineering tool

Abstract

The automotive industry strives towards optimizing performance, efficiency and quality in every conceivable aspect. One area of development is the steering system that has for a long time been governed by the usage of the Hydraulic Power Assisted Steering system (HPAS) throughout the automotive industry. As requirements demand higher efficiency, the need for a more flexible system increases. The alternative of Electric Power Assisted Steering systems (EPAS) provides the desired flexibility but also introduce issues with system inertia and vehicle stability. The demand for virtual development processes gives rise to a need for functional models of the EPAS system. This thesis includes developing a functional EPAS-model as well as investigating the fundamental effects of the EPAS system nature with regards to geometry and controller functionality.