RU2395108C2 - Optical-electronic tracking coordinator (versions) - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: in the first version, the optical-electronic tracking coordinator has a cardan suspension with angle and moment sensors placed on two mutually perpendicular axes Y, Z, with an objective lens, a main mirror, a counter-mirror fitted with a drive, and a photodetector mounted on the said suspension. The cardan suspension, on the inner frame of which there is a gyroscopic sensor, is mounted with possibility of rotating about the X axis which is perpendicular to the Y and Z axes, and is fitted with angle and moment sensors relative this axis. In front of the photodetector, which is made in form of two identical parallel multi-element lines, there is a filter for each of the said lines of the corresponding transmission range. The counter-mirror is mounted at an angle to the optical axis with possibility of turning about the said axis.

EFFECT: wider field of vision with simultaneous increase in accuracy of stabilising the optical axis and provision for noise immunity.

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Description

Combined in the application are three inventions of the same purpose, aimed at obtaining the same technical result in essentially the same way, but with different technical means, belong to the field of optical instrumentation and can find application in optoelectronic devices, for example, in infrared homing (GOS) guided missiles.

The main tasks facing the development of the Optoelectronic Tracking Coordinator (OESK) include:

- ensuring noise immunity from false thermal targets (LTC);

- high accuracy of stabilization of the optical axis, combined with the line of sight (LP) of the source;

- the possibility of deviation of the optical axis at large angles of the bearing.

The method of protection against LTC is based on the difference in the emission spectra of air targets and LTC. As a rule, homing heads designed for auto tracking of air targets operate in the range of 3-5 microns. LTCs, having geometric dimensions much smaller than those of targets, must have a high temperature in order to ensure radiation power comparable to the goals in the range of 3-5 μm, which determines their predominantly short-wavelength radiation spectrum. The system of target selection from LTC works on the principle of determining the blue-red ratio, i.e. two spectral channels for receiving radiation should be organized in the GOS and, based on the signal levels from one source, these channels conclude that this source belongs to the class of targets or LTC.

In a known technical solution, patent RU No. 2280228, F41G 7/26, discloses an optical coordinate system for guidance of an aircraft guided missile with a broadband photodetector, comprising a fairing, a gyroscope in a gimbal suspension, which ensures stabilization of the optical axis of the coordinator in space and its correction, in which the mirror a lens lens, a slit filter of infrared and ultraviolet range and a broadband photodetector.

The disadvantages of this optical tracking coordinator system are:

- the impossibility of manufacturing a receiver sensitive in the range of 0.015-4 microns, due to the lack of wide-gap materials in world practice;

- the impossibility of obtaining high-quality images in the ultraviolet 0.019-0.22 microns and infrared 2-3 microns in the same focal plane of a single optical system.

The closest technical solution, selected as a prototype for the first, second and third variants of the group of inventions, is an optoelectronic tracking coordinator described in patent RU 2101742, G02В 26/10, G01S 3/78, publ. 01/10/98, Bull. No. 1. The device comprises a stator, a rotor mounted in a gimbal suspension, including an optical system mounted on a permanent magnet of the rotor, consisting of a main mirror, which is a reflective layer deposited on the surface of the permanent magnet of the rotor, made with the curvature of the corresponding lens installed along the rays between the main mirror and a counter-mirror having a central hole and a spectro-splitter installed behind the counter-mirror, as well as two photodetectors, which are located in the central holes of the kontrzerkala projected onto the lens and so that their photosensitive pad aligned with the focal plane of the optical system.

The disadvantages of this technical solution include:

- the inability to provide large bearing angles due to the use of an internal gimbal;

- an increase in stabilization errors with an increase in the bearing angle (bearing term).

The task to be solved by each of the inventions of the group is the ability of the OESK to select and auto-track an air target when there are interference sources of optical radiation in the field of view of the device, as well as to enable the optical axis to be deflected to large angles of the bearing.

When implementing these inventions, the achieved technical result consists in expanding the field of view while increasing the accuracy of stabilization of the optical axis due to isolation of the drug from oscillations of the homing body along three axes and ensuring noise immunity from false targets.

To solve the problem and ensure the specified technical result in the well-known UESC, containing a gimbal with angle and moment sensors placed on two mutually perpendicular axes Y, Z, a lens with a counter-mirror equipped with a drive, and a photodetector, gimbal, mounted on it the inner frame of which the gyro sensor is located, is fixed with the possibility of rotation around the X axis, perpendicular to the Y, Z axes, and has angle and moment sensors about this axis, while in front of the photodetector, made in the form of two identical parallel multi-element lines, a filter is installed for each of the lines of the corresponding transmission range, and the counter-mirror is fixed at an angle to the optical axis with the possibility of rotation around it.

In the described embodiment, the indicated technical effect is achieved by the whole set of essential features, including the complete installation of the gimbal, the form of the photodetector in the form of two lines of photosensitive elements, the introduction of two filters, each of which is installed directly in front of the corresponding ruler, as well as the installation of a counter-mirror with a tilt to the optical axis. As a result, signals are received in parallel in two spectral ranges. By the ratio of signal levels from each source in two ranges, a decision is made on their belonging to the class of air targets or LTC.

The above principle of technical solutions for the first embodiment of the claimed group of inventions can be applied in the second invention. The technical result obtained in the second invention of the group also consists in expanding the field of view while increasing the accuracy of stabilization of the optical axis and ensuring noise immunity from the LTC.

The specified technical result is achieved by the fact that in the known optical-electronic tracking coordinator containing a gimbal with angle and moment sensors placed on two mutually perpendicular axes Y, Z, with a lens mounted therein with a counter-mirror equipped with a drive, and a photodetector, cardan the suspension, on the inner frame of which the gyro sensor is located, is fixed with the possibility of rotation around the X axis, perpendicular to the Y, Z axes, and has angle and moment sensors relative to this axis, while additionally a filter is installed in the focal plane of the lens associated with a rotation drive around the optical axis and made in the form of two spectral transmission zones separated by a line perpendicular to the optical axis and an optical system for transferring an image from the focal plane of the lens to the plane of the multi-element array of the photodetector, and the counter-mirror is mounted with the possibility of oscillation around an axis parallel to the multi-element line of the FPU, and is equipped with a position sensor that provides synchronization of the oscillation s kontrzerkala the filter rotation.

In the second embodiment, the invention is characterized by a combination of features, expressed in the presence of additional tools (new in comparison with the prototype of structural elements), the relative positions of the elements, the form of the elements and the form of the connections, which ensures the operability of the device. For example, “the filter is connected to the rotation drive ...”, “the counter-mirror is installed with the possibility of oscillation ...”, i.e. It is emphasized that the installation of the elements is not rigid, as usual, but different, which ensures the rotation of the filter and the oscillations of the counter-mirror with a functional (synchronized) connection between them.

The second option uses one line of photosensitive elements in the FPU and two filters. In this embodiment, the spectral channels operate sequentially. When the counter-mirror moves in one direction, radiation passes through one filter to one half of the FPU elements, through the second filter to the second half of the mirror, when the counter-mirror moves in the opposite direction, radiation to the first half of the FPU passes through the second filter, and to the second half of the elements through the first filter. Thus, in one period of the mirror oscillation, radiation is received in two spectral channels with a time shift. As a result, it is possible to determine the ratio of signal levels in two spectral channels for each source and to establish its belonging to the class of air targets or LTC.

The above technical solutions of noise immunity and stabilization of drugs at large angles of the bearing for the first and second variants of the claimed group of inventions also apply to the third invention. The problem solved by the third invention of the group and the technical result achieved are to expand the field of view while increasing the accuracy of stabilization of the optical axis and ensuring noise immunity from false thermal targets.

To solve the problem and ensure the claimed technical result in the well-known UESC, containing a gimbal with angle and moment sensors placed on two mutually perpendicular axes Y, Z, a lens with a counter-mirror equipped with a drive, and a photodetector, gimbal, mounted on it the inner frame of which the gyro sensor is located, is mounted for rotation around the X axis, perpendicular to the Y, Z axes, and is equipped with angle and moment sensors relative to this axis, while it is additionally introduced an optical system for transferring an image from the focal plane of the lens to the plane of the multi-element array of the photodetector, as well as a filter made in the form of two spectral zones separated along a line parallel to the multi-element array of the FPU, and installed in the focal plane of the object with the possibility of linear oscillations perpendicular to the dividing line of the spectral zones and the optical axis, and the counter-mirror is tilted to the optical axis, mounted to rotate around it and equipped with a position sensor, providing They synchronize the rotation of the counter-mirror and filter oscillations with a frequency ratio of 2: 1.

In the third embodiment, in the specified set of features (one line of sensitive elements of the FPU and two filters), the spectral channels operate sequentially in time. When the counter-mirror rotates for one revolution, the radiation at the FPU enters through the first filter, and during the next rotation of the counter-mirror, the radiation at the FPU enters through the second filter. As a result, it is possible to determine the ratio of signal levels in two spectral channels for each source, from which it is concluded that it belongs to the class of air targets or LTC.

The preference of the option depends on the design capabilities and the availability of the element base.

The invention is illustrated by drawings, where:

figure 1 - shows a General diagram of the device OESK, the optical system of which is made according to the first embodiment;

figure 2 - shows the relative position of the filters and sensitive elements (view along arrow A, view along arrow B);

figure 3 - shows the optical system OESK, made according to the second embodiment;

figure 4 - shows the optical system OESK, made according to the third embodiment.

Figure 5 - is a graphical depiction of the relationship of the position of the counter-mirror and the offset filter (in the third embodiment), while:

φ is the angle of rotation of the counter-mirror relative to the optical axis (OO);

Δ is the filter offset perpendicular to the optical axis (OO);

Uout is the output voltage of the counter-mirror position sensor.

OESK (figure 1) contains an optical system consisting of a main mirror 1, a counter-mirror 2, equipped with a drive 3 and a position sensor 4, an optical filter 5 and a FPU 6. The main mirror 1, mounted on the inner frame of the gimbal, can rotate around the Z axis , Y, X, equipped with appropriate torque and angle sensors 7-8; 9-10; 11-12, while the gyro sensor 13 is installed on the inner frame of the gimbal.

The output of the FPU 6 is connected to the video signal processing unit 14, connected through the computing unit 15 to the control unit of the line of sight 16, connected by inputs to the angle sensors z 8, y 10, x 12 and gyro sensor 13, and outputs with torque sensors along the X, Y axes, Z, 7-9-11.

2 and 4, an optical image transfer system 17 and a filter drive 18 are shown.

We consider the work of the UESK in the following examples.

Example 1

Radiation from sources in the coordinator’s field of view falls on the main mirror 1. Reflected from the mirror, then from the counter-mirror 2 and passing through the filter 5, the radiation is focused on the photosensitive area of the FPU 6 installed in the focal plane. A counter-mirror 2, inclined to the optical axis of the lens (OO) and rotating around it, transfers the image of the radiation source in a circle whose radius is determined by the angle of inclination of the counter-mirror 2. When the image crosses the FPU 6 photosensitive elements, a voltage pulse proportional to the radiation power incident on FPU 6. The received pulse contains information about the position of the radiation source relative to the optical axis (OO) and the radiation power in this spectral range. The signal from the FPU 6 is amplified and allocated in the video signal processing unit 14. For those signals (in two spectral channels) that belong to the same source, in block 15 the ratio of the levels of these signals (blue-red ratio) is calculated and its value determines the source true aerial target or to the LTC.

The target signal extracted in this way enters the LV 16 control unit, in which, taking into account the gyro sensor 13, a drive control signal is generated that ensures the optical axis is aligned with the line of sight.

Example 2

In accordance with the characteristics set forth in the second embodiment of FIG. 3, the counter-mirror 2, oscillating relative to the optical axis (OO), moves the source image across the line of the FPU 6. When the image crosses the photosensitive elements of the FPU 6, a voltage pulse proportional to the radiation received on FPU 6. The received pulse contains information about the position of the radiation source relative to the optical axis (OO) and the radiation power in this spectral range. When the counter-mirror 2 moves in one direction of the image, the signal enters the first half of the FPU 6 elements through the first half of the filter 5 (filter 5 is made in the form of two identical halves, the corresponding spectral range), and the signal enters the second half of the FPU 6 elements through the second half of the filter 5 The position of the sources relative to the optical axis of the OO and the amplitudes of their signals are remembered. When the counter-mirror 2 moves in the opposite direction, the process repeats. The signal comes through the second half of filter 5 to the first half of FPU 6, and the signal comes through the first half of filter 5 to the second half of FPU 6 elements. For those signals (in two spectral channels) that belong to the same source, in block 15 the ratio of these levels is calculated signals (blue-red ratio) and its value determines the source belongs to the true air target or to the LTC.

The target signal extracted in this way enters the LV 16 control unit, in which, taking into account the gyro sensor 13, a drive control signal is generated that ensures the optical axis is aligned with the line of sight.

Example 3

In the third embodiment (figure 4), the counter-mirror 2 rotating relative to the optical axis carries out the image transfer of the radiation source in a circle with the counter-mirror 2 speed, and the filter 5 of the corresponding spectral range, made in the form of two identical halves, moves across the optical axis with a frequency of half the frequency rotation of the counter-mirror 2 (see figure 5). Thus, alternately, through each revolution of the counter-mirror 2, radiation is received in the first and second spectral ranges. Then, for each source, the position relative to the optical axis and the amplitude of the signal, which are stored, are determined. For those signals (in two spectral channels) that belong to the same source, in block 15 the ratio of the levels of these signals (blue-red ratio) is calculated and its value determines whether the source belongs to the true air target or to the LTC.

The target signal extracted in this way enters the LV 16 control unit, in which, taking into account the gyro sensor 13, a drive control signal is generated that ensures the optical axis is aligned with the line of sight.

Moreover, in all cases, the signals of the angle sensors z (8), y (10), x (12) are used to develop target designation specified by external devices.

Thus, the proposed technical solutions provide an extension of the field of view (increase in bearing angles), which is achieved by constructive capabilities, i.e. by turning the coordinator around the Y axis by angles of ± 90 ° or more and by turning around the X axis by angles of more than 360 °. As a result, the optical axis deviates within a hemisphere or more. The stabilization accuracy is achieved by installing a biaxial gyro sensor on the inner frame of the gimbal, controlling the drives along the X, Y and Z axes, decoupling from the oscillations of the seeker along the X axis. These designs allow you to install multi-element FPUs and optical filters that provide radiation reception in two spectral ranges and provide noise immunity from LTC.

In this case, the second and third options allow using a simpler FPU, which consists of one ruler and spectral analysis consistent in time, in comparison with the first version.

For the manufacture of devices, standard blocks, materials and equipment may be partially used.

Claims (3)

1. Optoelectronic tracking coordinator (OECC), comprising a gimbal with angle and moment sensors placed on two mutually perpendicular axes Y, Z, a lens mounted in it, a main mirror, a counter-mirror equipped with a drive, and a photodetector, characterized in that the gimbal, on the inner frame of which the gyro sensor is located, is mounted for rotation around the X axis, perpendicular to the Y, Z axes, and is equipped with angle and moment sensors about this axis, while in front of the photodetector made in the form of two identical parallel multi-element arrays, a filter is installed for each of the arrays of the corresponding transmission range, and the counter-mirror is fixed at an angle to the optical axis with the possibility of rotation around it. 2. OESK, comprising a gimbal with angle and moment sensors placed on two mutually perpendicular axes Y, Z, a lens mounted therein, a main mirror, a counter-mirror equipped with a drive, and a photodetector, characterized in that the gimbal is on the inner frame of which the gyro sensor is mounted, rotatably mounted around the X axis, perpendicular to the Y, Z axes, and is equipped with angle and moment sensors relative to this axis, while a filter installed in the focal plane of the lens It is connected with a drive of rotation around the optical axis and made in the form of two spectral transmission zones separated by a line perpendicular to the optical axis, and an optical system for transferring the image from the focal plane of the lens to the plane of the multi-element array of the photodetector, and the counter-mirror is mounted with the possibility of oscillation around the axis parallel to a multi-element line of a photodetector, and is equipped with a position sensor that provides synchronization of counter-mirror oscillations with the rotation of the filter. 3. A UESC comprising a gimbal with angle and moment sensors placed on two mutually perpendicular axes Y, Z, a lens mounted in it, a main mirror, a rear-view mirror equipped with a drive, and a photodetector, characterized in that the gimbal is on the inner frame of which the gyro sensor is mounted, rotatably mounted around the X axis, perpendicular to the Y, Z axes, and is equipped with angle and moment sensors about this axis, while an optical system for transferring the image from the focal plane is additionally introduced into it the speed of the lens into the plane of the multi-element array of the photodetector and a filter made in the form of two spectral zones separated by a line parallel to the multi-element array of the photodetector and mounted in the focal plane of the lens with the possibility of linear oscillations perpendicular to the dividing line of the spectral zones and the optical axis, and the counter-mirror is tilted to the optical axis, mounted rotatably around it and equipped with a position sensor that provides synchronization of rotation of the counter-mirror filter oscillations with a frequency ratio of 2: 1.

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