Road lane trajectory estimation using yaw rate gyroscopes for intelligent vehicle control

Abstract

Vehicles equipped with advanced control systems can benefit significantly from an accurate estimation of the trajectory of the road ahead. This can be used, for example, to determine whether an obstacle, detected by a forward-looking sensor, is on the vehicle's path or in an adjacent lane. One method of deriving such an estimate is to combine a measurement of the yaw motion of the vehicle with some basic assumptions about the nature of the road. An adaptive cruise control system, equipped with a yaw-rate-based trajectory estimation, was demonstrated by Jaguar Cars at the PROMETHEUS 'Board Members Meeting' in 1994 with control that could distinguish between vehicles in adjacent lanes, even on motorway bends. This system showed a considerable benefit over those which did not make use of any steering information to select the sensor's field of interest, allowing the vehicle to follow traffic more naturally. The paper explores the consequences of the technique by modelling the nature of curves on motorway roads, the sources of noise on the yaw rate signal and the filtering used to form a reliable estimate of the road trajectory.