SU1624378A1 - Method for automatic data readout from scales of pointer instruments - Google Patents

Abstract

The invention can be used to automate the verification and calibration operations in the manufacture of measuring instruments with a pointer. The circuit of the invention — an increase in accuracy and productivity — is achieved by projecting the scale of the device onto a transmitting television camera with a digital raster so that the direction of the lines coincides with the direction of the scale, the video signals of the end of the pointer are extracted or when the pointer is dropped from the line closest to the scale, and the video signals of the calibrated marks are extracted from the video signals of the pointer. 1 il.

Description

The invention relates to a measuring technique and can be used to automate the verification and calibration operations in the manufacture of measuring instruments with a pointer.

The purpose of the invention is to increase accuracy and productivity.

The drawing is a diagram explaining the proposed method

The method is carried out as follows.

The scale of the device is projected onto a transmitting television camera with a digital raster so that the direction of the lines coincides with the direction of the scale. The control is carried out on the receiving CRT.

In this case, the instrument scale (scale projection) acquires a coordinate splitting in the coordinate system formed by the raster, i.e. the position of each scale point acquires the coordinate described by the n-bit binary code ao ... an, and the ao ... at bit linear coordinate X or angle p, and bits at + i ... an - coordinate Y or radius, respectively, when used for reading a television system with a rectangle or a circular raster.

The read direction is chosen so that in each frame the video signals from the scale objects arrive in a certain sequence: pointer video signals, video signals from marks on the scale and pointer pointer. For example, for instruments with a profile scale, the reading direction is from top to bottom (Yj Yj-m), and for devices with an arc scale, from rows of small diameter to rows of large diameter (p p). Since the reading is identical for any scales, the implementation of the method will be supported for arc scales.

Reference signals are sent to the instrument, and the pointer begins to move, occupying

The position is close to the turning marks depending on the magnitude of the error.

During the switching period, the coordinate y changes by

where P1 is the angle of the scale;

K is the number of tangible marks.

For widely used instruments with K 5 Lru 20%.

The coordinates of fixed objects for the same period remain unchanged or change slightly. These changes are caused by the final sensitivity value of the threshold elements forming the video signals, which determine the coordinates of the scale objects. For digital sweeps Lu) n, where d is an element of discretization on the line H

d

 + 1

When t 9 does not exceed 0.2% of the entire scale. The outcome of this DuPl. Therefore, we can conclude that the video signals from objects, the change in the coordinates of which satisfies the following expression

,(one)

are pointer video signals; K is const, the value of K is chosen based on the requirements of ensuring a reliable reading of K 10-20.

When the scale is projected and the reading direction is chosen, the last video signal from the object that satisfies expression (1) will be the video signal from the pointer pointer or if the pointer coincides with the video signal of the pointer on the line closest to the scale (drawing).

The coordinate of the last line p, containing the pointer video signal, is remembered and then the video signals are analyzed only on the lines.

RJ (2)

In this case, the outcome of the fact that the pointer

13 .

must overlap - - - h ,, where h is the height of the intermediate mark, when performing (2), the video signals from the marks will be read first.

Instrument manufacturing technology provides a pointer.

when the reference signal is applied at a distance from the calibrated mark, not exceeding 1–2, where y is the interval (angle) between the intermediate marks. Therefore, video signals from objects, coordinates

which satisfy the following expression

ru-u1 y, (3)

will be the video signals from the point being checked.

As a sign, for the selection of video signals of numeric marks from intermediate ones, the height or width of numerical marks can be chosen, for example, for widely used panel-mounted measuring instruments.

devices t4 about. 1.5-2tn.o., Where t4 о is the width of a numeric mark; tn.o. - the width of the intermediate mark.

When forming a raster, the image of the arc scale is divided into 32-103 points, which allows to write two arrays into 1 case of widely used 565RU5 memory (64 k).

The proposed method allows reading information from scales of any shape and using it for measurements over the entire range of accuracy.

Claims (1)

The invention of the method of automatic reading information from the scales of measuring devices with a pointer, which means that the scale of the instrument is projected onto a transmitting television camera with a digital raster so that the direction of the lines of the raster coincides with the direction of the scale, characterized in that, in order to improve the accuracy and performance, video signals the end of the pointer, with the coincidence of the pointer 5 with a scale mark, the video signals of the indicator are selected from the row closest to the scale, and the video signals of the marks being turned on are selected by the video signals of the indicator 7il