Method for acquiring angular velocity of gyro sensor and device for doing the same

Patent metadata

Field	Value
Publication number	US-10107626-B2
Application number	US-201514848344-A
Country	US
Kind code	B2
Filing date	Sep 9, 2015
Priority date	Apr 10, 2015
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

According to one embodiment, a method of acquiring rotational information of a gyro sensor includes sensing a predetermined physical quantity which depends upon an amplitude of a vibration in a second direction, the vibration in the second direction being based on Coriolis force that is applied to a movable body which is vibrating in a first direction, calculating rotational information of the movable body based on the sensed predetermined physical quantity, and stopping a vibration in the first direction of the movable body after the predetermined physical quantity is sensed.

First claim

What is claimed is:

1. A method of acquiring rotational information of a gyro sensor, comprising:
starting a vibration in a first direction of a movable body by releasing the movable body from a vibration stopping portion;
sensing a predetermined physical quantity which depends upon an amplitude of a vibration in a second direction different from the first direction;
calculating rotational information of the movable body based on the sensed predetermined physical quantity; and
stopping the vibration in the first direction of the movable body by catching the movable body by the vibration stopping portion after the predetermined physical quantity is sensed,
wherein the catching the movable body is performed by applying an electrostatic force between the movable body and an electrode.

2. The method of claim 1 , wherein the predetermined physical quantity is based on capacitance between a fixed electrode portion and a movable electrode portion included in the movable body.

3. The method of claim 1 , wherein the predetermined physical quantity is sensed when the vibration in the second direction is in a non-steady state.

4. The method of claim 3 , wherein the vibration in the first direction of the movable body is stopped before the vibration in the second direction reaches a steady state.

5. The method of claim 1 , wherein the vibration in the first direction of the movable body is stopped by catching the movable body when an amplitude of the vibration in the first direction reaches a peak.

6. The method of claim 1 , wherein the vibration in the first direction of the movable body is stopped by catching the movable body using a stopper.

7. The method of claim 1 , wherein the releasing the movable body is performed by reducing the electrostatic force between the movable body and the electrode.

8. The method of claim 1 , wherein a forced vibration in the first direction is not applied to the movable body after the movable body starts to vibrate in the first direction.

9. The method of claim 1 , wherein after a forced vibration in the first direction is applied to the movable body for a fixed period of time, the forced vibration to the movable body is stopped.

10. The method of claim 1 , wherein a resonant frequency in the first direction of the movable body and a resonant frequency in the second direction of the movable body are different from each other.

11. The method of claim 1 , wherein the rotational information is calculated based on the predetermined physical quantity sensed when the amplitude of the vibration in the second direction of the movable body reaches a peak.

12. The method of claim 1 , wherein the rotational information is calculated based on the predetermined physical quantity sensed at a specific timing after the movable body starts to vibrate in the first direction.

13. The method of claim 1 , wherein the movable body starts to vibrate in the first direction from a state in which the movable body is displaced forcibly in the first direction.

14. The method of claim 1 , wherein the vibration in the second direction is based on Coriolis force that is applied to the movable body which is vibrating in the first direction.

15. The method of claim 1 , wherein the vibration in the first direction is a free vibration.

16. A device which acquires rotational information of a gyro sensor, comprising:
a sensing unit which senses a predetermined physical quantity which depends upon an amplitude of a vibration in a second direction of a movable body which is vibrating in a first direction;
a rotational information calculating unit which calculates rotational information of the movable body based on the predetermined physical quantity sensed by the sensing unit; and
a vibration stopping portion which stops a vibration in the first direction of the movable body by catching the movable body,
wherein the vibration in the first direction of the movable body is started by releasing the movable body from the vibration stopping portion,
wherein the second direction is different from the first direction, and wherein the catching the movable body is performed by the vibration stopping portion by applying an electrostatic force between the movable body and an electrode.

17. The device of claim 16 , wherein the predetermined physical quantity is based on capacitance between a fixed electrode portion and a movable electrode portion included in the movable body.

18. The device of claim 16 , wherein the vibration stopping portion stops the vibration in the first direction of the movable body after the predetermined physical quantity is sensed.

19. The device of claim 16 , wherein the predetermined physical quantity is sensed when the vibration in the second direction is in a non-steady state.

20. The device of claim 19 , wherein the vibration stopping portion stops the vibration in the first direction of the movable body before the vibration in the second direction reaches a steady state.

21. The device of claim 16 , wherein a resonant frequency in the first direction of the movable body and a resonant frequency in the second direction of the movable body are different from each other.

22. The device of claim 16 , wherein the rotational information calculating unit calculates the rotational information based on the predetermined physical quantity sensed when the amplitude of the vibration in the second direction of the movable body reaches a peak.

23. The device of claim 16 , wherein the rotational information calculating unit calculates the rotational information based on the predetermined physical quantity sensed at a specific timing after the movable body starts to vibrate in the first direction.

24. The device of claim 16 , wherein the vibration stopping portion stops the vibration in the first direction of the movable body by catching the movable body when an amplitude of the vibration in the first direction reaches a peak.

25. The device of claim 16 , wherein the vibration stopping portion stops the vibration in the first direction of the movable body by catching the movable body using a stopper.

26. The device of claim 16 , wherein the vibration stopping portion stops the vibration in the first direction of the movable body by applying the electrostatic force between a projecting portion of the movable body and a drive electrode located near the projecting portion so as to cause the projecting portion to be in contact with the vibration stopping portion.

27. The device of claim 16 , wherein the releasing the movable body is performed by reducing the electrostatic force between the movable body and an electrode.

28. The device of claim 16 , wherein the vibration in the second direction is based on Coriolis force that is applied to the movable body which is vibrating in the first direction.

29. The device of claim 16 , wherein the vibration in the first direction is a free vibration.

30. A method of acquiring rotational information of a gyro sensor, comprising:
sensing a predetermined physical quantity which depends upon an amplitude of a vibration in a second direction of a movable body which is vibrating in a first direction;
calculating rotational information of the movable body based on the sensed predetermined physical quantity; and
stopping a vibration in the first direction of the movable body after the predetermin

Assignees

• Toshiba Kk

Inventors

• Ikehashi Tamio

Classifications

• G01C19/5719

  using planar vibrating masses driven in a translation vibration along an axis · CPC title

• G01C19/5762

  the sensing mass being connected to a driving mass, e.g. driving frames · CPC title

• G01C19/5726 Primary

  Signal processing · CPC title

• G01C19/5621 Primary

  the devices involving a micromechanical structure · CPC title