SU1659702A1 - Method for measuring averaged error of transparent limb of angle measuring instrument - Google Patents

Abstract

The invention relates to a measurement technique and can be used in opto-electronic devices to estimate the total error, taking into account the principle of operation of an angle-measuring device. The purpose of the invention is to improve accuracy by reducing the effect of errors due to the non-identity of the stroke design. In an angular measuring device that uses this type of limb, its limb stops and a technological mask with one transparent stroke is placed between the reading mask of one optocoupler and the limb, so that the luminous flux falling on the first stroke of a group of strokes of one optocoupler of the reading mask passes through it completely , and the rest of the strokes of the reading mask would be closed. The voltage readings are taken from the photo-receiver of the optocoupler. This operation is repeated with all the strokes of the limb. The data obtained is normalized to the maximum value. Then, the limb error of this series is measured along the shadow-light d N and light-shadow Ј N borders in each stroke of the limb, and the resulting limb error array is processed taking into account the previously obtained normalized data of a specific angle measuring device. 4 il. (Ls

Description

The invention relates to a measurement technique and can be used in optoelectronic devices for estimating the total error introduced by the inaccuracy of the angular position of the boundaries of the limb strokes in the pitch circle of optocouplers, taking into account the principle of the angle measuring instrument.

The aim of the invention is to improve the accuracy by reducing the effect of errors due to the non-identity of the stroke design.

FIG. 1 shows a profile projection of an optocoupler mating that reads a mask of one group of strokes, a limb, and a technological mask; in fig. 2 is a graph of output voltage U amplifier versus stroke number in the group of optocoupler readout mask; in fig. 3 - reading mask of the angle-measuring device and limb, view from the side of the radiator; in fig. 4 is a graph of the coefficients a t on the number of the stroke in the group of strokes of one optocoupler of the reading mask of the angle-measuring instrument,

about ate about vi

Yu

FIG. 1 The following notation is used: 1 - reading mask; 2 - limb of the angle measuring device; 3 - technological mask with one transparent stroke; 4-amplifier photodetector; 5 - photodetector; 6 - illuminator.

The method is implemented as follows.

For each type (series) of angle-measuring devices, the coefficients a 1 and a 2 sec. Are determined; as follows. In the assembled experimental angle-measuring device, the limb is locked in such a way that the projection of the bar-stroke group of one optac- rum of the reading mask coincides with the strokes of the limb. Between the reading mask 1 of one optocoupler and limb 2 a thin technological mask 3 is placed with one transparent stroke in size larger than one stroke of the optocoupler of the reading mask (Fig. 1). Technological mask 3 is oriented in such a way that the luminous flux falling on the first stroke of the group of strokes of one of the reading mask opars fully passes through it, and the remaining strokes of the reading mask 1 would be covered with an opaque part of it.

Then, the voltage U at the output of the amplifier 4 of the photodetector 5 is removed. Then the process mask 3 is shifted so that the luminous flux falling on the second stroke of the stroke group of the same optocoupler of the read mask completely passes through its second stroke, and the remaining strokes of the read mask 1 would be covered with an opaque part of the process mask 3. After that, the voltage U is taken at the output of the photodetector amplifier B. Similar operations are repeated with all m lines in the group of lines of one optocoupler read mask 1. Using the experimental data obtained for the voltage Um at the amplifier output (5 depending on the number of the stroke in the group of optocouplers of the reading mask, a graph of Um is plotted against the stroke number (Fig. 2). Then, the resulting graph is normalized using the formula U ( m)

UiaKc (m)

and take a (m) a m

These normalized stress values are the coefficients # 1, a2, and h, ..., From, used to determine the weight coefficients. Then, the limb error in each stroke is measured along the borders of shadow - light d i, b 2.6 h, ..., 5 s and sveg - shadow Ј 1. Ј2, Ј3 ЈN with an analyzer with one stroke

QSm -

ten

15

20

25

Home, the projection of which on the checked limb is equal to the projection of each stroke in the groups of strokes of the optocouplers of the reading mask of the angle measuring device.

The resulting array of limb errors and each stroke along the edges of the shadow is the light 5i, 52, dz,.

Ј 1, Ј2, Јз, | N is treated according to the formula:

 Kn (5r + fr), (1)

p –o p - 1

where 6 g is the limb error in each stroke on the shadow-light border; Ј g - limb error in each stroke on the light-shadow border,

I is an independent variable characterizing the angle by which the limb error of the angle-measuring instrument is measured, 1 & f N;

N is the number of strokes on the limb of the angle measuring device;

q is the number of groups of strokes on the reading mask of the angle-measuring device;

m is the number of strokes in the group of strokes of one optocoupler of the reading mask of an angle-measuring instrument,

r is independent variable

p is an independent variable Q p (q-1);

 - coefficients of the weight of the error of the boundaries of the limb stroke in the total signal of the error of the limb of the angle-measuring device

(2)

2gm2; ae e - 1

The proposed method makes it possible to obtain a higher accuracy estimate of the error introduced by the limb in the angle gauge by means of semi-natural prototyping.

Claims (1)

Invention Formula The method of determining the averaged error of the transparent limb of the angle-measuring device, consisting in the sequential measurement of the individual error of each stroke and the processing of measurement results, characterized in that, in order to improve accuracy by reducing the effect of errors caused by the non-identity of the stroke pattern, for each of strokes the determination of the individual errors at the boundaries of the light — the shadow and the shadow — light is made, and in the processing of the results, these additional definitions are used.