Patent ID: 8028789
Filing Date: 2011-10-04
Classification: B62D

Abstract:
1. An adaptive control variable gear ratio (VGR) steering system for a vehicle, said system comprising: a VGR device that changes a gear ratio between a hand-wheel angle of a hand-wheel of the vehicle and a road wheel angle of the vehicle; a vehicle speed sensor providing a vehicle speed signal of a speed of the vehicle; a hand-wheel angle sensor providing a hand-wheel angle signal of the hand-wheel angle of the vehicle; a VGR sub-system that provides a VGR signal to the VGR device for changing the gear ratio, said VGR sub-system using the vehicle speed signal and the hand-wheel angle signal to determine the gear ratio based on a combination of both vehicle speed and a desired yaw-rate gain; and a style and skill characterization processor that is responsive to vehicle sensor signals from vehicle sensors, said style and skill characterization processor determining a driver's driving style and skill, said style and skill characterization processor providing a driver's driving style and skill signal to the VGR sub-system of the type of driver driving the vehicle, said VGR sub-system using the vehicle speed signal, the hand-wheel angle signal and the driver's driving style and skill signal to determine the gear ratio, where the gear ratio is reduced from a nominal value as the vehicle speed increases for drivers of greater skill.