RU2794558C1 - Device for measuring the height of celestial bodies - Google Patents

Abstract

FIELD: nautical astronomy.

SUBSTANCE: invention relates to nautical astronomy and can be used in astronavigation systems of marine carriers for measuring the heights of celestial bodies above the level of the visible horizon. The substance of the claimed invention is as follows. The device for measuring the heights of celestial bodies contains blocks for orienting and measuring the heights of celestial bodies above the line of the visible horizon, a photodetector, which is part of the video camera of the wide-field video system, and a wide-angle lens connected to the video camera, which forms the plane of images of celestial bodies of the entire celestial hemisphere and the line of the visible horizon in a single system coordinates for measuring the heights of celestial bodies above the line of the visible horizon, in which the celestial bodies and the visible horizon are displayed in the image plane on the photodetector simultaneously in real time. The claimed device has a three-axis orientation for obtaining a fixed image on the screen of a video monitor when the movable medium is tilted and rotated. At the same time, the wide-angle lens is connected to the video camera using a mount that allows adjustment to find the best image plane.

EFFECT: improving the technical characteristics of the device for measuring the heights of celestial bodies, namely, in simplifying the design with a simultaneous increase in reliability.

3 cl, 1 dwg

Description

The invention relates to nautical astronomy and can be used in astronavigation systems of marine carriers (hereinafter referred to as ANS) (and on other oscillating bases and moving carriers) for measuring the heights of celestial bodies above the level of the visible horizon.

An astrovising device is known (patent RU 2682260, publication date 03/18/2019), containing an input optical system with a lens, in the focal plane of which a radiation detector with a multichannel video output is installed. The video system is located on the inner frame of the suspension. There is also an external suspension frame and an information processing unit. The inner and outer frames of the suspension are equipped with drives and angle meters. The information processing unit has the possibility of parallel processing of video data.

The disadvantage of the known astrovising device is the absence of a third suspension frame and a third drive with a rotation angle meter, which in sea conditions (rolling) will not allow you to get a still video image of the starry sky and the horizon line, and increase the measurement errors of the heights of celestial bodies. At the same time, to improve the accuracy of measurements, suspensions with a high accuracy of “holding” the horizon will be required.

Known invention "Two-star marine collimator sextant" (patent RU 2178144, publication date 10.01.2002). A two-star marine collimator sextant contains a telescope with a wide field of view, an eyepiece with an illuminated grid of mutually perpendicular vertical and horizontal threads intersecting on the optical axis of the pipe, an objective and a beam splitter to create two optical channels, one of which has a measuring prism with a reading device, which is sequentially behind the first one, a second beam splitter is installed, which creates a third channel, in which a collimator with a weight projects a grid of vertical and horizontal threads in the field of view of the eyepiece, precisely superimposed on the grid of eyepiece threads when the sighting plane of the device coincides with the vertical plane of the weight. The specified match is fixed by the operator.

An invention is also known (patent RU No. 2120108, publication date 10.10.1998), which is a device for determining astronomical coordinates, containing a prismatic astrolabe - a reference prism, a lens, a horizontal mirror mounted on a turntable, and a time sensor, as well as a television a sensor installed in the focal plane of the astrolabe, the main and additional tilt sensors, a computing device containing a unit for calculating the mutual angular distances of two star images, a threshold device, a coordinate transformation unit, a motor switching unit, an inverter, a unit for calculating astronomical coordinates. The base of the entire device is mounted on three "legs", one of which is rigidly connected to the base, and the other two are each connected to its motor through a gearbox. The invention makes it possible to use the device at high latitudes from a rocking base.

The disadvantages of the known inventions are that the measurement errors of the height of the celestial body depend on the preparedness of the operator, which is determined by the ability of the human eye to distinguish and fix the positions of the celestial bodies relative to the horizon line and the possibility of devices for "holding" the horizon line using mechanical suspensions.

A known method and device for determining the azimuth (application RU 2010137011, publication date of the application 20.03.2012), taken as a prototype.

The device and method for determining the azimuth include an orientation unit relative to the local horizon and a plumb line, an optical sighting unit for point light sources, a unit for measuring horizontal angles, a unit for measuring vertical angles - for measuring the heights of celestial bodies above the line of the visible horizon, a unit for measuring time and computing block.

The disadvantage of the device and method is the laboriousness of reducing measurement errors associated with the need to replace blocks of orientation, sighting, measurement.

Thus, the technical problem in this area is the complexity of the structures, as well as their low reliability. The present invention is aimed at solving the named technical problem.

The technical result of the invention consists in improving the technical characteristics of the device for measuring the heights of celestial bodies, namely, in simplifying the design while increasing reliability.

In addition, thanks to the proposed device, the independence from orientation and sighting errors is increased, and the measurement error is also reduced.

The technical result is achieved by the fact that the device for measuring the heights of celestial bodies, containing blocks for orienting and measuring the heights of celestial bodies above the line of the visible horizon, according to the invention, contains a photodetector (hereinafter referred to as FP), which is part of a video camera of a wide field video system (hereinafter referred to as HSW), with a matrix high-resolution and connected to a video camera wide-angle lens (hereinafter referred to as WOB), which forms the plane of images of celestial bodies of the entire celestial hemisphere and the line of the visible horizon in a single coordinate system for measuring the heights of celestial bodies above the line of the visible horizon, in which the celestial bodies and the visible horizon are displayed in a plane images on the photodetector simultaneously in real time.

Additional features of the invention:

- has a 3-axis orientation to obtain a still image on the screen of the video monitor when tilting and turning the movable carrier;

- a wide-angle lens is connected to the video camera using a mount that allows adjustment to find the best image plane.

The essence of the invention is illustrated by the following graphic material, namely, figure 1, which schematically shows the relative position of the AF and SOB in the proposed device, and also shows the objects of observation (celestial bodies, the line of the visible horizon, etc.) and optical rays coming from them, where:

1 - FP;

2-SHOB;

3 - attachment point for the SHOB to the video camera;

4 - external optical beams indicating the field of view of the video camera;

5 - internal optical rays coming from celestial bodies and the line of the visible horizon;

6 - visible horizon line (horizon);

7 - video camera.

The device for measuring the heights of celestial bodies contains a high-resolution FP 1, which is part of the video camera VSHP, connected to the video camera 7 through the mount 3 SHOB 2 to the video camera. Attachment 3 allows adjustment to find the plane of the best image.

The device allows you to form a plane of images of celestial bodies of the entire celestial hemisphere (at least 90° in the field of view of the video camera) and the line of the visible horizon 6 in a single coordinate system and measure the heights of all celestial bodies (h1, h2, h3, h4) above the line of the visible horizon in image plane simultaneously in real time.

The device has a 3-axis orientation (Z, Y and X) to obtain a still image on the screen of the video monitor when tilting and turning the movable media.

When using the proposed device in the ANS, the error in measuring the heights of astro-navigation luminaries does not depend on the errors of the orientation and guidance blocks, and can be reduced by replacing the FP matrix 1 with a higher resolution FP matrix (with a smaller pixel size Pix) provided that the energy potential of the pixel Pix is the same.

Measurements of the height of the celestial body above the line of the visible horizon 6 are made by calculating the number of elements of the FP matrix 1 (pixels -Pix) located on the conditional perpendicular line, lowered from the energy center of the image of the celestial body to the line of the visible horizon.

The computing unit, realizing in a single coordinate system the graph of a conditionally lowered perpendicular from the energy center of the image of the selected celestial body to the line of the visible horizon 6, calculates the number of elements (pixels) of the FP 1 that fit along the line of the conditionally lowered perpendicular and, having multiplied the previously known angular size of one element (pixel) of FP 1 by the number of elements (pixels) of FP 1, calculates the value of the angle, which is the height of the celestial body (h) above the line of the visible horizon 6.

From geometric optics, the relationship between the angular size of an object and the linear size of its image is known:

where: Y' - the linear size of the image of the object on the matrix FP 1;

w is the angular size of the object in the space of objects;

F' is the focal length of the lens.

The field of view of the video camera 7 in the space of objects is determined as follows:

where: Z' - half of the linear size of the FP 1.

The angular size of one pixel (Pix°) is also determined by formula (3).

where: Npix - the number of pixels on one side, corresponding to the calculated value of the field of view of the video camera 7.

Having set the coordinate grid of the FP matrix in Pix ° and using the calculated value of the angular size of the pixel Pix ° and their number, located along the conventionally lowered perpendicular from the energy center of the celestial body to the line of the visible horizon (Npix s-l), it is easy to calculate the angle, which is the height of the celestial body (h):

Pointing and orientation errors are in a single coordinate system of the celestial body and the line of the visible horizon 6, and may not be taken into account when calculating the height. The measurement errors of the heights of celestial bodies above the visible horizon 6 when using the proposed device will be determined mainly only by the angular size of the minimum element of the two-dimensional image (Pix) on the FP 1 and the energy potential of the pixel.

Thus, the angle Y measured by the device between the direction to the luminary and the visible horizon 6, indicated in Fig.1, in the plane of objects (celestial bodies) can be measured in the image plane with an accuracy determined by the resolution of the FP matrix 1.

Thanks to the proposed invention, the technical characteristics of the device for measuring the heights of celestial bodies are improved, namely, the design is simplified with a simultaneous increase in its reliability.

Claims (4)

1. A device for measuring the heights of celestial bodies, containing blocks for orienting and measuring the heights of celestial bodies above the line of the visible horizon, characterized in that it contains a photodetector, which is part of a video camera of a wide-field video system, with a high-resolution matrix and a wide-angle lens connected to the video camera, which forms a plane of images of celestial bodies of the entire celestial hemisphere and the line of the visible horizon in a single coordinate system for measuring the heights of celestial bodies above the line of the visible horizon , in which the celestial bodies and the visible horizon are displayed in the image plane on the photodetector simultaneously in real time. 2. The device according to claim. 1, characterized in that it has a three-axis orientation to obtain a still image on the video monitor screen when tilting and turning the movable carrier. 3. The device according to claim 1, characterized in that the wide-angle lens is connected to the video camera using a mount that allows adjustment to find the best image plane.

Images