Vehicle Compass Using Telematics Unit and Vehicle Sensor Information
First Claim
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 compass application that calibrates the yaw rate sensor to subsequently estimate vehicle heading information in the absence of GPS location information;
14 Assignments
0 Petitions
Accused Products
Abstract
A software compass used during a GPS outage calculates vehicle heading and presents it upon request. The software compass gathers information from a yaw rate sensor, wheel steering angle sensor, wheel speed sensor, and PRNDL gear position sensor to calculate vehicle heading using a weighting algorithm. Because the yaw rate sensor data is a central factor in calculating vehicle heading, the quality of calibration of the yaw rate sensor is of importance. The disclosed calibration algorithm calculates the yaw rate bias and scale factors to calibrate the yaw rate sensor.
-
Citations
20 Claims
-
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 compass application that calibrates the yaw rate sensor to subsequently estimate vehicle heading information in the absence of GPS location information; - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A method for detecting a vehicle location parameter using internally-referenced vehicle sensor information, the internally-referenced vehicle sensor information comprising at least yaw rate information from a yaw rate sensor, the method comprising the steps of:
-
recording a GPS-based vehicle location at a first time moment; gathering first yaw rate parameters including yaw rate sensor data, wheel steering angle sensor data, wheel speed sensor data, and gear position data; calibrating the yaw rate sensor by reference to the GPS-based vehicle location and the first yaw rate parameters; at a second time moment after calibration of the yaw rate sensor, detecting a GPS outage such that GPS position data is unavailable; after the second moment, gathering second yaw rate parameters including yaw rate sensor data, wheel steering angle sensor data, wheel speed sensor data, and gear position data; and calculating estimated vehicle heading information at substantially the second moment from the second yaw rate parameters. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15)
-
-
16. A method for detecting a vehicle location parameter using internally-referenced vehicle sensor information, the internally-referenced vehicle sensor information comprising at least yaw rate information from a yaw rate sensor, the method comprising the steps of:
-
recording a GPS-based vehicle location at a first time moment; gathering first yaw rate parameters including yaw rate sensor data, wheel steering angle sensor data, wheel speed sensor data, and gear position data; calibrating the yaw rate sensor by reference to the GPS-based vehicle location and the first yaw rate parameters; at a second time moment after calibration of the yaw rate sensor, detecting a GPS outage such that GPS position data is unavailable; after the second moment, gathering second yaw rate parameters including yaw rate sensor data, wheel steering angle sensor data, wheel speed sensor data, and gear position data; and calculating estimated vehicle heading information at substantially the second moment from the second yaw rate parameters. - View Dependent Claims (17, 18, 19, 20)
-
Specification