Calibration Transfer Between Two Devices
Disclosed is a system to automatically calibrate a compass (e.g., a compass with a magnetometer) of an aerial vehicle. Auto calibration may occur at power up of the aerial vehicle or shortly thereafter. The system may be configured to rotate a gimbal, coupled with the aerial vehicle, in a wide range of rotational angles. The system may calibrate, in response to the rotations, a compass of the gimbal to obtain one or more calibration values and transfers the one or more calibration values to the aerial vehicle. The system may add a calibration difference value to the calibration value to obtain an adjusted calibration and may store the adjusted calibration for use with the compass of the aerial vehicle.
1 . A method to automatically calibrate a compass of an aerial vehicle, the method comprising:
rotating a gimbal coupled with the aerial vehicle to a plurality of angular rotations;
measuring a magnetic field, with a gimbal compass of the gimbal, at the plurality of angular rotations to obtain a plurality of measurements;
calculating a calibration value for the gimbal compass based on the measurements;
transferring the calibration value to the aerial vehicle;
adding a calibration difference value to the calibration value to obtain a current calibration value for the aerial vehicle; and
storing the current calibration for use with the compass of the aerial vehicle.
2 . The method of claim 1 , wherein the calibration difference value is a factory-calculated calibration value.
3 . The method of claim 1 , wherein the calibration difference value is a user-defined calibration value.
4 . The method of claim 1 , wherein the aerial vehicle transmits a signal to a remote controller indicating completion of the automatic calibration.
5 . The method of claim 1 , wherein the aerial vehicle illuminates an LED as an indication of completion of the automatic calibration.
6 . The method of claim 1 , wherein the aerial vehicle determines its orientation based on a measurement with the compass of the aerial vehicle and based on the current calibration.
7 . A method to automatically calibrate a compass of an aerial vehicle, the method comprising:
powering up an aerial vehicle;
rotating a gimbal coupled with the aerial vehicle in a wide range of angular rotations;
calibrating, in response to the rotations, a gimbal compass of the gimbal to obtain a calibration value, the gimbal compass including a magnetometer;
transferring the calibration value to the aerial vehicle;
adding a calibration difference value to the calibration value to obtain a current calibration value for the aerial vehicle; and
storing the current calibration for use with the compass of the aerial vehicle.
8 . The method of claim 7 , wherein the calibration difference value is a factory-calculated calibration value.
9 . The method of claim 7 , wherein the calibration difference value is a user-defined calibration value.
10 . The method of claim 7 , wherein the aerial vehicle transmits a signal to a remote controller indicating completion of the automatic calibration.
11 . The method of claim 7 , wherein the aerial vehicle illuminates an LED as an indication of completion of the automatic calibration.
12 . The method of claim 7 , wherein the aerial vehicle determines its orientation based on a measurement with the compass of the aerial vehicle and based on the current calibration.
13 . A computer readable storage medium comprising stored instructions to automatically calibrate a compass of an aerial vehicle, the instructions when executed by a processor cause the processor to:
power up an aerial vehicle;
rotate a gimbal coupled with the aerial vehicle in a wide range of angular rotations;
calibrate, in response to the rotations, a gimbal compass of the gimbal to obtain a calibration value, the gimbal compass including a magnetometer;
transfer the calibration value to the aerial vehicle;
add a calibration difference value to the calibration value to obtain a current calibration for the aerial vehicle; and
store the current calibration for use with the compass of the aerial vehicle.
12 . The computer readable storage medium of claim 13 , wherein the calibration difference value is a factory-calculated calibration value.
13 . The computer readable storage medium of claim 13 , wherein the calibration difference value is a user-defined calibration value.
14 . The computer readable storage medium of claim 13 , further comprising stored instructions that when executed by the processor causes the processor to transmit a signal to a remote controller indicating completion of the automatic calibration.
15 . The computer readable storage medium of claim 13 , further comprising stored instructions that when executed by the processor causes the processor to illuminate an LED as an indication of completion of the automatic calibration.
16 . The method of claim 13 , wherein the aerial vehicle determines its orientation based on a measurement with the compass of the aerial vehicle and based on the current calibration.