JPH06100615B2 - Angular velocity calibrator - Google Patents

Description

TECHNICAL FIELD The present invention relates to an angular velocity calibrator for calibrating angular velocity.

(Prior Art) Angular velocity is one of the important factors for evaluating the driving performance of a vehicle, and an angular velocity meter is used to measure this angular velocity. To calibrate a conventional gyro, place an gyro to be inspected (referred to as a trial gyro) on the same turntable together with another reference gyro, and rotate the pedestal A method of comparing the peak value and the phase with an output oscilloscope or a pen recorder is known. In this method, one standard gyro must always be prepared in addition to the sample gyro, but since the gyro is extremely expensive, it is not possible to prepare a standard gyro for each calibration. It's tough. Also, the sensor part is on the table, and the power supply and the widening part are connected to the slip ring, the cable, and the sensor through the cable, so that a problem easily occurs in the connection part. In addition, the end users often use different types of angular velocimeters from different manufacturers, making it almost impossible to handle slip rings, and it is a cross for users to check all of their angular velocities. The reality is that there is only a check method.

As another calibration method, set the trial angular velocimeter on the vehicle, run the vehicle at a constant speed on the circumference of a constant radius, measure the time required for one lap, and calculate the angular velocity (deg / sec),
There is a method of comparing the value with the output of the sample gyro. This method requires the vehicle to travel at each speed, and actually traveling at a constant speed on a constant circumference requires a very high degree of skill. In the latter method, the linearity with respect to the input can be checked, but the frequency characteristic and the phase characteristic cannot be checked.

(Object and Structure of the Invention) The present invention has been made in view of the above points, and an object thereof is to simply calibrate an angular velocity meter, and in order to achieve this object, a rotation for mounting a sample angular velocity meter for rotation. A stand,
Rotation angle output means for outputting a rotation angle signal corresponding to the rotation of the turntable with two output values having a phase shift difference of 90 degrees, and rotation direction determination means for detecting the rotation direction of the turntable based on the rotation angle signal. , A reference time output circuit that outputs a reference time signal, a rotation angle signal, a reference time signal, and the rotation direction from the rotation direction determination means, and the rotation angle signal is measured by the reference signal to rotate the turntable. Calculating means for outputting the period by logarithm, storage means for storing the logarithmic value and its corresponding antilogarithm, converting the logarithmic value from the calculating means to the antilogarithmic value, and a latch circuit for temporarily storing the value converted by the storage means. And a converter that is connected to the latch circuit and converts a digital value into an analog value,
An angular velocity calibrator is constituted by a display device for displaying the output value of the sample angular velocity meter and the output value of the rotation output means converted by the converter.

(Example) The present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of an angular velocity calibrator according to the present invention.

In the angular velocity calibrator of this embodiment, the rotary encoder 2 is mounted on the shaft portion of the rotary table 1a that rotates by mounting the sample angular velocity meter K.
Test bench 1 with attached and rotary encoder 2
A rotation direction determination circuit 3 for determining the rotation direction of the rotary base 1a based on two pulse train signals S (rotation angle signals) having different 90 ° phases generated in proportion to the rotation angle of the rotary base 1a,
A pulse train signal S from the rotary encoder 2 and a time base oscillator 4 that generates a clock serving as a time reference.
The following pulse train signal arrives from the digital counter 5 that measures the cycle of, the ROM 6 that stores the logarithmic straight line conversion table that converts the output from the digital counter 5 into the linear scale because the output from the digital counter 5 is the logarithmic scale, and the rotary encoder 2. Up to the latch circuit 7 that latches the output from the ROM 6 and the output from the latch circuit 7 to an analog value
A D / A converter 8, a level adjuster 9 for arbitrarily adjusting the level of an analog value, and a monitor display 10 for displaying the output of the level adjuster 9 as a reference angular velocity value on a monitor.

FIG. 2 shows the structure of the test table 1. The shaft 1b of the rotary table 1a is supported by the bearing 1c, the coupling 1d is provided at the lower end of the shaft 1b, and is connected to the rotary shaft of the rotary encoder 2. .

As shown in FIG. 3, the monitor display 10 of the angular velocity calibrator of this embodiment includes a meter 20 for displaying the angular velocity of the rotary base 1a as a reference angular velocity, and a meter 30 for displaying the output of the trial angular velocity meter on a monitor. Are arranged side by side, and digital meters 20a and 30a are incorporated in each meter so that they can be monitored both in analog and digital.
Below each meter, there are rotary mode selector switches 21 and 31 that can be set to inspect the instrument and the sample gyro with an analog meter, a digital meter, or both. For example, the modes can be set by the following combinations. Mode Analog meter Digital meter M ₁ A OFF M ₂ A B M ₃ B A M ₄ B A M ₅ OFF B where A is the reference angular velocity value output from the angular velocity calibrator according to the present invention, and B is the angular velocity output from the trial angular velocity meter. Means that the value is displayed. For example, in mode M ₂ , the reference angular velocity value is displayed on the meter 20 in an analog manner, and the reference angular velocity value of the sample angular velocity meter is displayed on the digital meter 20a.

The calibration mode can be set for each of the meters 20 and 30.

Next, the operation of the angular velocity calibrator according to the present invention and the calibration procedure therefor will be described.

When the sample angular velocity meter K is placed on the rotary table 1a of the test table 1 and rotated (however, one rotation or less is sufficient), the two-phase pulse train signal S having a phase difference of 90 ° is output from the rotary encoder 2. The rotation direction determination circuit 3 determines the rotation direction of the turntable 1a based on the phase difference of the two-phase pulse train signal S.

On the other hand, the digital counter 5 measures the cycle of the pulse train signal S by counting the clock from the time base oscillator 4 at the timing of the two-phase pulse train signal S. Since the output of the digital counter 5 is a log scale, the output is used as an address to be converted into a linear scale by the ROM 6, and the converted value is temporarily held in the latch circuit 7. The output of the latch circuit 7 is D / A converted by the D / A converter 8 and then level-adjusted by the level adjuster 9 and displayed on the meter 20 of the monitor display 10.

On the other hand, the output from the sample angular velocity meter K placed on the rotary table 1a is amplified and level-adjusted by a circuit (not shown) and is also displayed on the meter 30 of the monitor display 10.

Now, the mode selector switch provided on the monitor display 10.
If both meters are set to analog display from 21 and 31 (corresponding to mode M ₁ described above),
Since the reference angular velocity value is displayed in analog form on 20 and the angular velocity value by the trial angular velocity meter is displayed on meter 30, the user can adjust the deflection of the needle of the trial angular velocity meter based on the deflection of the needle of the meter 20. Good. This adjustment is a turntable
Move the sample velocimeter above 1a to another location.

It is also possible to calibrate in another calibration mode. For example, the mode M ₂ or
If the calibration mode corresponding to M ₃ is set, the digital display value of the trial angular velocity meter can be adjusted with the reference angular velocity value digitally displayed on the meter 20 as a reference.

Further, by setting the calibration mode M _3, since the angular velocity value of the trial gyro with reference angular velocity value in the digital meter 20a of one meter 20 are digitally displayed in an analog display, digital display criteria angular velocity value It is possible to adjust the deflection of the needle of the sample gyro as a reference.

In the above embodiment, the output of the rotary encoder was once converted into a cycle using a digital counter, but the output of the rotary encoder can be directly frequency processed. According to this method, since the output of the rotary encoder changes linearly, the circuit configuration does not become complicated, and the angular velocity can be easily obtained. The frequency characteristic can be improved by increasing the number of pulses of and increasing the reference time.

(Effects of the Invention) As described above, in the present invention, the sample angular velocimeter is placed on the rotary table and rotated, and the reference angular velocity value is displayed on the first monitor display according to the rotation angle of the rotary table. In addition, the angular velocity value based on the output of the trial angular velocity meter is displayed on the second monitor display unit, and the sample angular velocity meter is calibrated by comparing the display values on both monitor display units. It is not necessary to always prepare a reference angular velocimeter, and it is not necessary to actually set the sample angular velocimeter on the vehicle and drive the vehicle at a constant speed on a constant circumference. In addition, it is possible to easily configure the angular velocity under any condition that only adjusts the rotational speed of the turntable, and to check the frequency characteristic and the phase characteristic.

[Brief description of drawings]

FIG. 1 is a block diagram showing a circuit configuration of an angular velocity calibrator according to the present invention, FIG. 2 is a diagram showing a structure of a test stand used in the present invention, and FIG. 3 is a monitor display portion of the angular velocity calibrator according to the present invention. FIG. 1 ... Test table, 1a ... Turning table, 2 ... Rotary encoder, 3 ... Rotation direction discriminating circuit, 4 ... Time base oscillator, 5 ... Digital counter, 6 ... ROM, 7 ...
… Latch circuit, 8 …… D / A converter, 9 …… Level adjuster, 10 …… Monitor display

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuya Watanabe 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Nissan Motor Co., Ltd. (JP, U) Actually opened 60-68474 (JP, U) Actually opened 56-29468 (JP, U)

Claims (1)

[Claims] 1. A rotary table on which a sample angular velocity meter is mounted and rotated, and a rotary angle output means for outputting a rotary angle signal corresponding to the rotation of the rotary table with two output values having a phase difference of 90 degrees. From a rotation direction discriminating means for detecting the rotation direction of the turntable based on a rotation angle signal, a reference time output circuit for outputting a reference time signal, the rotation angle signal, the reference time signal, and the rotation direction discriminating means. Inputting the rotation direction of the rotation angle signal, measuring the rotation angle signal with the reference signal, and outputting the rotation cycle of the turntable in logarithm, and storing the logarithm value and the corresponding antilogarithm. Storage means for converting the logarithmic value from the to a true value, a latch circuit for temporarily storing the value converted by the storage means, a converter connected to the latch circuit for converting a digital value into an analog value, the trial angular velocity Output value of the meter and before An angular velocity calibrator, comprising: a display device for displaying the output value of the rotation output means converted by the converter.