Calibration of multi-axis accelerometer in vehicle navigation system
AssigneeMagellan DIS, Inc.
InventorsJohn David Begin, Ka C. Cheok
Life of this patent
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Abstract
A navigation system includes a multi-axis accelerometer which can be installed in the vehicle in any unknown orientation. The orientation of the axes of the accelerometer is automatically determined by the navigation system. The signals from the accelerometer are then used to propagate the position of the vehicle.
Claims23
A vehicle navigation system comprising:
- a multiple-axis inertial sensor generating a plurality of sensor signals, each associated with one of said sensor axes;
- a transformation matrix relating said plurality of signals to said vehicle axes;
- and
- a processor transforming said plurality of signals into motion information correlating to vehicle axes.
A vehicle navigation system comprising:
- an inertial sensor generating a plurality of sensor signals each associated with a sensor axis of said sensor, said inertial sensor mounted in an unknown orientation in a vehicle;
- a processor programmed to determine a gravity orientation of said sensor relative to gravity and determining a longitudinal orientation of said sensor relative to a longitudinal axis of a vehicle;
- and
- means for propagating a position of a vehicle based upon said plurality of sensor signals, said gravity orientation and said longitudinal orientation.
A vehicle navigation system comprising:
- an inertial sensor generating a plurality of sensor signals each associated with a sensor axis of said sensor, said inertial sensor mounted in an unknown orientation in a vehicle;
- a transformation matrix relating said plurality of signals to axes of said vehicle;
- and
- means for propagating a position of a vehicle based upon said plurality of sensor signals.
A method for calibrating an inertial sensor in a vehicle navigation system including the steps of:
- a) receiving a plurality of signals from said inertial sensor;
- b) generating a transformation matrix based upon said plurality of signals;
- and
- c) transforming said plurality of signals from said inertial sensor into a reference frame of the vehicle.
A method for calibrating an inertial sensor mounted in an unknown orientation in a vehicle navigation system including the steps of:
- a) determining a gravity orientation of the inertial sensor relative to gravity based upon a first plurality of signals from the sensor;
- b) determining a longitudinal orientation of the inertial sensor relative to a longitudinal axis of the vehicle based upon a second plurality of signals from the inertial sensor;
- and
- c) transforming a third plurality of signals from said inertial sensor into a reference frame of the vehicle.
Dependencies are inferred from the claim text.