Additional 4WS and Driver Interaction

Abstract

This investigation is based on a complex 4-wheel vehicle model of a passenger car that includes steering system and drive train. The tyre properties are described for all possible combined longitudinal and lateral slip values and for arbitrary friction conditions. The active part is an additional steering system of all 4 wheels, additionally to the driver's steering wheel angle input. Three control levels are used for the driver model that thereby can follow a given trajectory or avoid an obstacle. The feedback control of the additional 4 wheel steering is based on an observer which can also have adaptive characteristics. Moreover a virtual vehicle model in a feedfonvard scheme can provide desired steering characteristics. T o get information for critical situations a cornering manoeuvre with sudden p-split conditions is simulated. Further a similar manoeuvre is used to evaluate the reentry in a high friction area from low friction conditions. And finally the performance of the controller is shown in a severe lane change manoeuvre.

Understanding and Modeling the Human Driver

“…Numerous driver modeling efforts exist in the literature and many contain various features noted above. Certain models that are primarily focused on an optimal characterization of driver control performance such as formula-1 driving [131,132], or related types of automated or more idealized driver performance [51,[133][134][135][136] are duly noted as providing a type of benchmark performance that reflects highly practiced and skilled sets of driver control behaviors. However, the emphasis here is more on the types of models that can represent or mimic a broad range of driver control behavior, and therefore include provisions for many of the cited limitations and attributes of human drivers.…”

Study of the problem and the idea of operation of four-wheel-steering cars

“…Standard simulation studies reflecting the operation of 4WS controllers include models of varying complexity [9,15,31]. More example it is possible to find in: [35,38,48].…”