Calibration apparatus, calibration method, and manufacturing method for an electronic device

1. A calibration apparatus for calibrating a sensor of an electronic device, the sensor for detecting rotation of the electronic device in three-dimensional space and the sensor including orthogonal R-axis, P-axis, and T-axis directions, the calibration apparatus comprising:

a holder defining orthogonal X-axis, Y-axis, and Z-axis directions for the holder;

a first motor for causing the holder to rotate at a predetermined rotational speed about a predetermined rotation axis;

a second motor for causing the holder to rotate about the Y-axis;

a Y-axis stopper for restricting a rotational position of the holder between a Y-axis reference position, a positive Y-axis perpendicular position positive 90 degrees from the Y-axis reference position about the Y-axis, and a negative Y-axis perpendicular position negative 90 degrees from the Y-axis reference position about the Y-axis,

a third motor for causing the holder to rotate about the Z-axis;

a Z-axis stopper restricting a rotational position of the holder between a Z-axis reference position, a positive Z-axis perpendicular position positive 90 degrees from the Z-axis reference position about the Z-axis, and a negative Z-axis perpendicular position negative 90 degrees from the Z-axis reference position about the Z-axis, wherein:

the holder is operable to receive and retain the electronic device such that: (i) the R-axis of the sensor of the electronic device is coaxial with the X-axis of the holder, (ii) the P-axis of the sensor of the electronic device is coaxial with the Y-axis of the holder, and (iii) the T-axis of the sensor of the electronic device is coaxial with the Z-axis of the holder,

the second motor, the third motor, the Y-axis stopper and the Z-axis stopper cause the holder rotate such that: (i) the holder is at the Y-axis reference position about the Y-axis, (ii) the holder is at the Z-axis reference position about the Z-axis, (iii) the X-axis is coaxial with the predetermined rotation axis, and (iv) the first motor causes the holder to rotate about the X-axis, and the sensor of the electronic device to rotate about the R-axis, at the predetermined rotational speed to obtain first output values from the sensor,

the second motor, the third motor, the Y-axis stopper and the Z-axis stopper cause the holder rotate such that: (i) the holder is at the Y-axis perpendicular position about the Y-axis, (ii) the holder is at the Z-axis reference position about the Z-axis, (iii) the Z-axis is coaxial with the predetermined rotation axis, and (iv) the first motor causes the holder to rotate about the Z-axis, and the sensor of the electronic device to rotate about the T-axis, at the predetermined rotational speed to obtain second output values from the sensor, and

the second motor, the third motor, the Y-axis stopper and the Z-axis stopper cause the holder rotate such that: (i) the holder is at the Y-axis reference position about the Y-axis, (ii) the holder is at the Z-axis perpendicular position about the Z-axis, (iii) the Y-axis is coaxial with the predetermined rotation axis, and (iv) the first motor causes the holder to rotate about the Y-axis, and the sensor of the electronic device to rotate about the P-axis, at the predetermined rotational speed to obtain third output values from the sensor.

2. The calibration apparatus according to claim 1 , further comprising a lock control portion operating to prevent the holder from rotating about the Y-axis when the rotational position of the holder is in the Y-axis reference position and in the Y-axis perpendicular position.

3. The calibration apparatus according to claim 1 , wherein:

the electronic device further comprises an acceleration sensor for detecting a magnitude of a gravitational acceleration applied thereto;

when the second motor, the third motor, the Y-axis stopper and the Z-axis stopper cause the holder rotate such that the X-axis is coaxial with the predetermined rotation axis, the first motor causes: (i) the holder to rotate such that the Y-axis is vertical and axially aligned with a gravitational force to take a positive P-axis gravitational reading from the acceleration sensor, and (ii) the holder to rotate 180 degrees to take a negative P-axis gravitational reading from the acceleration sensor;

when the second motor, the third motor, the Y-axis stopper and the Z-axis stopper cause the holder rotate such that the Z-axis is coaxial with the predetermined rotation axis, the first motor causes: (i) the holder to rotate such that the X-axis is vertical and axially aligned with a gravitational force to take a positive R-axis gravitational reading from the acceleration sensor, and (ii) the holder to rotate 180 degrees to take a negative R-axis gravitational reading from the acceleration sensor; and

when the second motor, the third motor, the Y-axis stopper and the Z-axis stopper cause the holder rotate such that the Y-axis is coaxial with the predetermined rotation axis, the first motor causes: (i) the holder to rotate such that the Z-axis is vertical and axially aligned with a gravitational force to take a positive T-axis gravitational reading from the acceleration sensor, and (ii) the holder to rotate 180 degrees to take a negative T-axis gravitational reading from the acceleration sensor.

4. A calibration method for calibrating a sensor of an electronic device, the sensor for detecting rotation of the electronic device in three-dimensional space and the sensor including orthogonal R-axis, P-axis, and T-axis directions, the calibration method comprising:

providing a holder having orthogonal X-axis, Y-axis, and Z-axis directions;

providing a first motor for causing the holder to rotate at a predetermined rotational speed about a predetermined rotation axis;

providing a second motor for causing the holder to rotate about the Y-axis;

providing a Y-axis stopper for restricting a rotational position of the holder between a Y-axis reference position, a positive Y-axis perpendicular position positive 90 degrees from the Y-axis reference position about the Y-axis, and a negative Y-axis perpendicular position negative 90 degrees from the Y-axis reference position about the Y-axis, providing a third motor for causing the holder to rotate about the Z-axis;

providing a Z-axis stopper restricting a rotational position of the holder between a Z-axis reference position, a positive Z-axis perpendicular position positive 90 degrees from the Z-axis reference position about the Z-axis, and a negative Z-axis perpendicular position negative 90 degrees from the Z-axis reference position about the Z-axis;

fixing the electronic device to the holder such that: (i) the R-axis of the sensor of the electronic device is coaxial with the X-axis of the holder, (ii) the P-axis of the sensor of the electronic device is coaxial with the Y-axis of the holder, and (iii) the T-axis of the sensor of the electronic device is coaxial with the Z-axis of the holder;

causing the second motor, the third motor, the Y-axis stopper and the Z-axis stopper to rotate the holder such that: (i) the holder is at the Y-axis reference position about the Y-axis, (ii) the holder is at the Z-axis reference position about the Z-axis, (iii) the X-axis is coaxial with the predetermined rotation axis, and (iv) the first motor causes the holder to rotate about the X-axis, and the sensor of the electronic device to rotate about the R-axis, at the predetermined rotational speed to obtain first output values from the sensor;

causing the second motor, the third motor, the Y-axis stopper and the Z-axis stopper to rotate the holder such that: (i) the holder is at the Y-axis perpendicular position about the Y-axis, (ii) the holder is at the Z-axis reference position about the Z-axis, (iii) the Z-axis is coaxial with the predetermined rotation axis, and (iv) the first motor causes the holder to rotate about the Z-axis, and the sensor of the electronic device to rotate about the T-axis, at the predetermined rotational speed to obtain second output values from the sensor; and

causing the second motor, the third motor, the Y-axis stopper and the Z-axis stopper to rotate the holder such that: (i) the holder is at the Y-axis reference position about the Y-axis, (ii) the holder is at the Z-axis perpendicular position about the Z-axis, (iii) the Y-axis is coaxial with the predetermined rotation axis, and (iv) the first motor causes the holder to rotate about the Y-axis, and the sensor of the electronic device to rotate about the P-axis, at the predetermined rotational speed to obtain third output values from the sensor.

5. The method of claim 4 , further comprising writing calibration data calculated from the first, second and third output values to a nonvolatile memory of the electronic device.

6. The method of claim 4 , further comprising locking the holder from rotating about the Y-axis when the rotational position of the holder is in the Y-axis reference position and in the Y-axis perpendicular position.

7. The method of claim 4 , further comprising locking the holder from rotating about the Z-axis when the rotational position of the holder is in the Z-axis reference position and in the Z-axis perpendicular position.

8. The method of claim 4 , wherein the electronic device further comprises an acceleration sensor for detecting a magnitude of a gravitational acceleration applied thereto, the method further comprising:

when the second motor, the third motor, the Y-axis stopper and the Z-axis stopper cause the holder rotate such that the X-axis is coaxial with the predetermined rotation axis, the first motor causes: (i) the holder to rotate such that the Y-axis is vertical and axially aligned with a gravitational force to take a positive P-axis gravitational reading from the acceleration sensor, and (ii) the holder to rotate 180 degrees to take a negative P-axis gravitational reading from the acceleration sensor;

when the second motor, the third motor, the Y-axis stopper and the Z-axis stopper cause the holder rotate such that the Z-axis is coaxial with the predetermined rotation axis, the first motor causes: (i) the holder to rotate such that the X-axis is vertical and axially aligned with a gravitational force to take a positive R-axis gravitational reading from the acceleration sensor, and (ii) the holder to rotate 180 degrees to take a negative R-axis gravitational reading from the acceleration sensor; and

when the second motor, the third motor, the Y-axis stopper and the Z-axis stopper cause the holder rotate such that the Y-axis is coaxial with the predetermined rotation axis, the first motor causes: (i) the holder to rotate such that the Z-axis is vertical and axially aligned with a gravitational force to take a positive T-axis gravitational reading from the acceleration sensor, and (ii) the holder to rotate 180 degrees to take a negative T-axis gravitational reading from the acceleration sensor.