Patent ID: 8108171

Claim:
A method for calibrating an uncalibrated magnetic compass and at least one uncalibrated gyroscope, the method comprising: receiving an output of the uncalibrated gyroscope while stationary; determining a gyroscope bias error of the uncalibrated gyroscope based upon the output of the uncalibrated gyroscope while stationary; rotating a sensor platform with the uncalibrated magnetic compass and the uncalibrated gyroscope thereon; receiving bearing information from the uncalibrated compass and angular rotation information from the uncalibrated gyroscope during a time period corresponding to the rotation of the sensor platform exactly 360 degrees; integrating the angular rotation information from the uncalibrated gyroscope over the time period; determining an amount of gyroscope rotation from the integrated angular rotation information; determining a gyroscope gain error based upon a difference between the determined amount of gyroscope rotation and the corresponding bearing information; determining magnetic field strength variations based upon the angular rotation information; and determining a compass bearing error based upon the determined magnetic field strength variations.