Patent ID: 7398145
Filing Date: 2008-07-08
Classification: B60T,B60W,B62D

Abstract:
1. An apparatus for estimating a grip factor of a wheel of a vehicle, the apparatus comprising: a steering factor detecting unit that detects at least one of steering factors including a steering torque and steering effort applied on a steering system extending from a steering wheel to a suspension in a vehicle; a longitudinal force estimating unit that estimates a driving or braking force of the wheel; a self-aligning torque estimating unit that estimates self-aligning torque generated in the wheel on the basis of the steering factor detected by the steering factor detecting unit, estimates a quantity of influence of the driving or braking force estimated by the longitudinal force estimating unit on the self-aligning torque, and estimates a value obtained by removing the quantity of influence from the self-aligning torque as new self-aligning torque; a vehicle state variable detecting unit that detects a state variable of the vehicle; a wheel factor estimating unit that estimates at least one of wheel factors including side force and slip angle applied on the wheel on the basis of the state variable detected by the vehicle state variable detecting unit; and a grip factor estimating unit that estimates a grip factor of the wheel on the basis of change of the self-aligning torque newly estimated by the self-aligning torque estimating unit relative to the wheel factor estimated by the wheel factor estimating unit.