JP2003156513A - Servo accelerometer with built-in gyro - Google Patents

Abstract

PROBLEM TO BE SOLVED: To integrate an optical fiber gyro and an accelerometer so as to be capable of detecting both an acceleration and an angular velocity by one servo accelerometer. SOLUTION: The servo accelerometer with a built-in gyro is constituted in such a way that an optical fiber (20) is installed inside a pendulum (3) comprising a flexure (2), that the acceleration is detected by the movement in the right and left direction of the pendulum (3) and that the input of the angular velocity is detected by the optical fiber (20) inside the pendulum (3).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a servo accelerometer with a built-in gyro, and more particularly, by providing an optical fiber on a pendulum of the servo accelerometer, the accelerometer and the optical fiber gyro are combined into one case. The present invention relates to a new improvement for enabling the provision of

[0002]

2. Description of the Related Art Various optical fiber gyros and servo accelerometers that have been conventionally used have been developed. Among them, the optical fiber gyro is disclosed in, for example, Japanese Unexamined Patent Publication No. 2000-65584. As disclosed, an optical system is configured by connecting an optical system component to a ring-shaped optical fiber, and an electrical system including an optical fiber gyro signal processing circuit for performing signal processing is connected to the optical system. Was configured.

Although not shown as an accelerometer, in general, a pair of detectors detect a displacement of a pendulum hanging through a hinge due to an acceleration input, and detect it as a change in capacitance. Was there.

[0004]

Since the conventional optical fiber gyro and servo accelerometer are configured as described above, there are the following problems. That is, in order to detect both the angular velocity and the acceleration, both the optical fiber gyro and the accelerometer must be provided in a device such as a flying object, which requires a large installation space and weight and also a large cost. It was.

The present invention has been made to solve the above problems, and in particular, by providing an optical fiber on the pendulum of a servo accelerometer, one accelerometer and an optical fiber gyro are combined. An object of the present invention is to provide a servo accelerometer with a built-in gyro that can be provided in the case.

[0006]

A gyro built-in type servo accelerometer according to the present invention comprises a longitudinal pendulum having a flexure whose one end is fixed to a case, and an optical fiber provided in the pendulum and wound in a ring shape. A pair of yokes provided on the case and having magnets on the inner wall and arranged on both sides of the pendulum, a moving coil provided on the pendulum for magnetically acting on the magnet, and on both sides of the lower part of the pendulum. Further, the pendulum is provided in a non-contact state with first and second detectors, the optical fiber detects an angular velocity input from the outside, and each of the detectors detects acceleration. The optical fiber is connected to an optical fiber gyro signal processing circuit via an optical coupler.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a gyro built-in accelerometer according to the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 indicates a case whose overall shape is a box shape (only a part of which is shown in the figure), and a pendulum 3 having a flexure 2 is provided on the top 1 a of the case 1. It is provided so as to reciprocate along the left-right direction indicated by the arrow A.

At the upper and lower positions of the pendulum 3, a pair of ring-shaped moving coils 4 are arranged in a cylindrical shape. On the inner wall (not shown) of the case 1, a pair of yokes 8A, 8 having a magnet 5 arranged so as to be located in the middle of each moving coil 4 is provided.
B is provided, and the moving coil 4 and the magnet 5 constitute a torquer 6.

The pendulum 3 is made of a dielectric material and
On both sides of the lower portion 3a of the pendulum 3, first and second detectors 10 and 11 made of a metal plate or the like are arranged so as to be in non-contact with the lower portion 3a. 1
The gap change between 0 and 11 can be used as a capacitance change (other well-known magnetic detection methods may be used) to detect the input state of acceleration, and the detection signal is the detection system circuit 1.
2 is input.

The pendulum 3 is constructed as shown in FIG. That is, the pendulum 3 includes a holding portion 3A having the flexure 2 and a fiber bobbin 3B connected to the holding portion 3A, and an optical fiber of a predetermined length is provided in the ring-shaped recess 3Ba of the fiber bobbin 3B. 20 is wound many times and provided.

Each of the yokes 8A, 8B, the magnet 5,
The pendulum 3, the moving coil 4, and the optical fiber 20 are disassembled and shown in FIG. 3, and the optical fiber 20 is provided inside the thickness t of the pendulum 3.

Next, the case where the acceleration A and the angular velocity ω actually input from the outside are detected in the above configuration will be described. That is, when the acceleration A is input in the state of FIG. 1, the pendulum 3 swings in either the left or right direction, and the change at this time is detected by the first and second detectors 10 and 11, and the moving coil 4 is moved. The pendulum 3 is servo-controlled so that the tilt state of the pendulum 3 is corrected and becomes vertical by being controlled by the magnetic action of a known control unit of the torquer 6 including the magnet 5.

When an angular velocity ω is externally input in the above-described state, the gyro output is output by the optical fiber 20, for example, the Sagnac effect of light according to the well-known phase modulation method, to the optical coupler 30 and the optical fiber gyro signal. It can be obtained by signal processing by the processing circuit 31.

[0014]

Since the servo accelerometer with a built-in gyro according to the present invention is configured as described above, the following effects can be obtained. That is, since the optical fiber is wound around the pendulum that detects the acceleration, both the acceleration and the angular velocity input to the pendulum can be obtained with one gyro built-in servo accelerometer, which is smaller than conventional ones. It is possible to achieve a low price.

[Brief description of drawings]

FIG. 1 is a sectional view showing a servo accelerometer with a built-in gyro according to the present invention.

2 is a cross-sectional view of the pendulum of FIG.

FIG. 3 is an exploded perspective view of a main part of FIG.

[Explanation of symbols]

1 case 2 flexure 3 pendulum 3a lower part 4 moving coils 5 magnets 8A, 8B yoke 10, 11 First and second detectors 20 optical fibers 30 Optical coupler 31 Optical fiber gyro signal processing circuit

Claims (2)

[Claims] 1. A flexure having one end fixed to the case (1).
(2) an elongated pendulum (3), an optical fiber (20) provided in the pendulum (3) and wound into a ring, and the case
A pair of yokes (8A, 8B) provided on both sides of the pendulum (3) and having a magnet (5) on the inner wall provided in (1),
A moving coil (4) provided on the pendulum (3) for magnetically acting on the magnet (5), and a lower part of the pendulum (3)
The first and second detectors (10, 11), which are arranged on both sides of (3a) and are in non-contact with the pendulum (3), are provided with the optical fiber (20) to provide an angular velocity from the outside. A servo accelerometer with a built-in gyro, which is configured to detect an input and to detect acceleration by each of the detectors (10, 11). 2. The gyro built-in servo acceleration according to claim 1, wherein the optical fiber (20) is connected to an optical fiber gyro signal processing circuit (31) through an optical coupler (30). Total.