Patent ID: 8165806
Filing Date: 2012-04-24
Classification: G01C,G01S

Abstract:
1. A vehicle position detection system for using a telematics unit and vehicle sensor information to estimate a current vehicle position, the system comprising: a yaw rate sensor that measures an angle of turn of the vehicle; a wheel steering angle sensor that measures the angle at which one or more vehicle wheels are turned; a wheel speed sensor that measures a speed of rotation of one or more wheels of the vehicle; a gear position sensor that senses a current gear condition of a transmission of the vehicle; a global positioning system that provides vehicle location and heading; and a software compass application that calibrates the yaw rate sensor using at least yaw rate parameter values provided by: the yaw rate sensor, the wheel steering angle sensor, and wheel speed sensor, and wherein the compass application calibrates the yaw rate sensor by applying a minimization algorithm to a function of a scale factor and a yaw rate bias, and wherein the yaw rate sensor is used to estimate vehicle heading information in the absence of GPS location information.