JPH07318577A - Acceleration measuring unit - Google Patents

Abstract

PURPOSE:To obtain an acceleration measuring unit for examining various characteristics of an acceleration sensor, especially of a low acceleration sensor, accurately and easily by subjecting an object to be tested, i.e., an acceleration sensor, to the gravitational acceleration from an arbitrary direction. CONSTITUTION:An acceleration sensor 8 is mounted on a turn table 1 which is turned by a predetermined angle at a time so that an index plunger 6 is fitted in the groove 5. The acceleration sensor 8 is subjected to the gravitational acceleration at each angle and a signal from the sensor 8 is taken out through a slip ring in order to evaluate the characteristics. The performance of acceleration sensor can be measured in a desired direction by varying the fixing direction (X, Y and Z directions) of the acceleration sensor 8 to the turn table 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acceleration measuring device suitable for investigating the characteristics of an acceleration sensor for detecting acceleration such as force, acceleration and magnetism, and more particularly to an acceleration sensor as a device under test. The present invention relates to an acceleration measuring instrument that allows gravitational acceleration to act from an arbitrary direction to accurately and easily investigate various characteristics of an acceleration sensor, particularly the characteristics of a low acceleration sensor.

[0002]

2. Description of the Related Art Conventionally, an acceleration sensor detects the force, acceleration, magnetism, etc. of an object that moves in three dimensions, such as a robot or an airplane, or an object that moves in a two-dimensional plane, such as an automobile, and the movement of the object or Various devices mounted on an object are controlled according to their respective purposes. At present, various types of acceleration sensors are used to realize the above-mentioned control. When an acceleration sensor is incorporated into a control device, what characteristics does the acceleration sensor actually use have? Need to know.

FIG. 5 shows the configuration of a vibration tester currently used as a means for investigating various characteristics of such an acceleration sensor.
This vibration tester basically has the same configuration as a speaker, 20 is a vibrating table, 21 is a coil, 22 is a magnet, and an acceleration sensor (sample) 23 as a device under test is It is fixed to the vibration table 20. Shaking table 2
0 is attracted to the magnet 22, but when a magnetic force is generated in the coil 21 in accordance with the input signal, the magnetic line of force of the magnet 22 changes and the vibrating table 20 is vibrated, and this vibration causes the acceleration sensor 23 as the device under test. Apply acceleration to. The output from the acceleration sensor 23 at this time causes the acceleration sensor 23 to
To investigate various characteristics of.

[0004]

However, when the characteristics of the acceleration sensor are investigated by the vibration tester as described above, there are the following problems. (1) Since the vibration tester investigates the acceleration characteristics by applying a reciprocal acceleration to the DUT mounted on the test bench, the vibration tester has a mechanism of the tester, which causes a reciprocating motion (vertical movement) of the test bench. The test table may tilt slightly, and it is difficult to accurately reciprocate the test table. That is, components other than the reciprocal direction act on the acceleration sensor during the test, and the acceleration is measured including the interference output, which is not sufficient to precisely investigate various characteristics of the sensor. The interference output is as shown in FIG.
When an acceleration is applied in the X-axis sensitivity direction, an output may be generated in the Y-axis sensitivity direction, as shown in, and this output is called interference output.

(2) Since the vibration tester uses the vibration generator to actually give vibration to the acceleration sensor to perform the test, the test device is inevitably large-scale and, in addition, the vibration Since the physical acceleration must be actually applied to the acceleration sensor, the performance test of the acceleration sensor is troublesome.

Therefore, the present invention proposes a new acceleration measuring instrument utilizing gravity and aims to solve the above-mentioned problems. That is, in this acceleration measuring device, a gravitational acceleration in any direction (that is, a DC component acceleration) is applied to an acceleration sensor attached to a turntable, and the characteristics of the acceleration sensor can be measured using the gravitational acceleration. Therefore, various characteristics of the low acceleration sensor can be accurately tested without requiring a large-scale device.

[0007]

In order to achieve the above object, the technical solution adopted by the present invention is a test table 1 which is always rotatable in a vertical plane, and a test table 1 which is provided at a right angle. An acceleration measuring instrument comprising a shaft 2, a support base 3 for horizontally supporting the shaft, and a positioning mechanism capable of rotationally positioning the test base 1 at predetermined angles.

[0008]

Operation: The acceleration sensor 8 is installed on the turntable 1, and the turntable is rotated at each angle so that the angle indexing plunger 6 is fitted into the groove 5 of the turntable 1. A signal from the acceleration sensor 8 for each angle is taken out through a slip ring (not shown) to evaluate the characteristics of the acceleration sensor. In this measuring instrument, the performance of the acceleration sensor in the desired direction can be measured by changing the mounting method (X direction, Y direction, Z direction) of the acceleration sensor 8 on the turntable 1.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a gravitational acceleration measuring device according to this embodiment, and FIG. 2 is an enlarged perspective view of a main part of FIG. Figure 1
In the figure, 1 is a turntable as a test table to which an acceleration sensor as a device under test can be attached, and a shaft 2 is fixed at a right angle to the center of rotation of the turntable. The shaft 2 is horizontally supported by the support base 3 via the bearings 4 at two positions in the longitudinal direction. The support base may have any form as long as it can rotatably and horizontally support the shaft 2.

Grooves 5 are formed around the turntable 1 at a constant angle, and an angle indexing plunger 6 fitted into the groove is attached to the support base 3. The angle indexing plunger 6 is fitted into the groove 5 by the biasing force of the spring 7, and the groove 5 and the angle indexing plunger 6 constitute a positioning mechanism for the rotational position of the turntable 1. As the positioning mechanism, various forms can be used as long as they can accurately determine and hold the rotation angle of the turntable 1.

In the gravitational acceleration measuring device constructed as described above, the acceleration sensor measures as follows. 1. An acceleration sensor 8 is installed on the turntable 1.
At this time, the gravitational acceleration G is always acting on the acceleration sensor 8 in the direction shown in FIG. 2. The turntable is rotated at each angle so that the angle indexing plunger 6 is fitted into the groove 5 of the turntable 1. 3. A signal from the acceleration sensor 8 for each angle is taken out and measured through a slip ring (not shown). In this measuring instrument, the acceleration sensor 8 for the turntable 1
The performance of the acceleration sensor in the desired direction can be measured by changing the mounting method (X direction, Y direction, Z direction). Although the turntable is rotated by hand in the above embodiment, the performance of the acceleration sensor can be automatically measured by rotating it by a predetermined angle by a stepping motor or the like.

FIG. 3 shows the measurement results obtained by the above centrifugal force acceleration measuring device. FIG. 3 shows the results of a survey of a sensor having detection sensitivity in the directions of three axes that are orthogonal to each other by the centrifugal force acceleration measuring device according to the present invention, when this acceleration measuring device is investigated. FIG. 6A shows the output result when the sensor base is rotated around the Z axis of the acceleration sensor. FIG. 6B shows an output result when the sensor base is rotated around the X axis of the acceleration sensor. As is clear from this result, according to the present acceleration measuring device, the gravitational acceleration can be accurately exerted in the predetermined direction of the acceleration sensor as the device under test, so that various characteristics of the sensor can be precisely investigated. . Especially, a great effect can be expected in the performance investigation of the low acceleration sensor.

[0013]

As described in detail above, according to the acceleration measuring device of the present invention, the acceleration sensor installed on the turntable can apply the gravitational acceleration (that is, the acceleration of the DC component) from an arbitrary direction. The characteristics of the sensor can be precisely tested. Further, since the gravitational acceleration is almost constant on the earth (9.8 m / s ² ), accurate acceleration sensor measurement can be performed at anytime and anywhere with reference to the acceleration of 1 G. Furthermore, since this measuring instrument does not use a vibration generator, the measuring instrument itself can be simply constructed and the manufacturing cost is low. It is possible to obtain excellent effects such as.

[Brief description of drawings]

FIG. 1 is a perspective view of an acceleration measuring device according to an embodiment of the present invention.

FIG. 2 is an enlarged perspective view of a main part of FIG.

FIG. 3 is a graph showing a result of testing an acceleration sensor using the acceleration measuring device according to the present invention.

FIG. 4 is an explanatory diagram of interference output.

FIG. 5 is a schematic configuration diagram of a conventional vibration tester.

[Explanation of symbols]

 1 test table (turntable) 2 axis 3 support 4 bearing 5 groove 6 angle indexing plunger 8 DUT (acceleration sensor)

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Kazuaki Takami 2-5-5 Keihan Hondori, Moriguchi City, Osaka Sanyo Electric Co., Ltd.

Claims (3)

[Claims] 1. A test table 1 which is always rotatable in a vertical plane,
An acceleration characterized by comprising a shaft 2 provided at a right angle to the test stand 1, a support stand 3 for horizontally supporting the shaft, and a positioning mechanism capable of rotationally positioning the test stand 1 at predetermined angles. Measuring instrument. 2. The acceleration according to claim 1, wherein the positioning mechanism includes a groove 5 formed in the test table 1 and an angle indexing plunger 6 fitted in the groove 5. Measuring instrument. 3. The acceleration measuring instrument according to claim 1, wherein the test stand 1 is configured to be rotatable by a driving means.