RU2697939C1 - Method of target design automation at aiming at helicopter complex - Google Patents

Abstract

FIELD: military equipment.

SUBSTANCE: method relates to military equipment, in part of onboard armament sighting systems of helicopters using different methods of aiming guided missile guidance systems. According to the method of aiming at the helicopter complex, when using the optical-electronic system of an OPS, the operator is able to observe the scene and to detect targets at long ranges and with better resolution, rather than if it would be monitored using an optoelectronic system mounted on the missile, having the worst angular resolution. Image with an OPS is recalculated taking into account the metric (image_1, further – standard) to the image taken from the sensor of the rocket chamber (image_2), the image_1 is only a fragment of the image_2, with preservation (albeit coarse) of all features of the scene area in form of certain brightness anomalies of both the target and its immediate environment. Then, metric alignment of these two images is performed, considering the fact that both images are obtained at one time and from one place (albeit from different sensors), then it can be stated that these images are very similar. Differences are observed in the brightness pattern and the noise level. Subsequent processing by the gradient regional operator contrasts the brightness anomalies of both images, which enables to find the position of said fragment (reference) on image_2 and specify a target designation point using correlation comparison means with the normalized cross-correlation function.

EFFECT: technical result of the method is to reduce the time for capturing the target by the operator and to increase the operating range of the missile, which is ultimately equivalent to reducing the probability of hitting the helicopter with means of object air defense.

1 cl, 1 dwg

Description

The invention relates to military equipment using methods of aiming guided missiles in guidance systems used in sighting systems of on-board weapons of helicopters. Improving sighting systems can increase the effectiveness of guided missiles with multispectral homing heads for targets chosen by the operator.

The known method of "two rays" for aiming and pointing the missile at the target, which was used in the surveillance and optical optical electronic system (OPS) of the first generations of guided missiles of the air-to-surface class, placed on helicopters, "Guided missile guidance method (RF patent No. 2436031) "[1]. This method, which consists in pointing the target line at the target by the operator and controlling the rocket until it is aligned with the eye by measuring the deviation of the position of the rocket from the target, has obvious disadvantages: the low speed of the rocket and, therefore, the long flight time (20-25 s) , the presence of an unaffected zone in front of the firing position 300-600 m deep, operator fatigue, etc. Further improvement of this approach was connected with the fact that tracking the missile, measuring its deviation from the aiming line, developing and Transferring teams on board the flying missiles, and then it controls, it has been assigned to the automatic guidance system. Subsequent changes were reduced to the use of a second guidance system, which was supposed to replace the actions of the operator.

Any improvement in the sighting optical-electronic system (OPS) of the carrier, which provides the crew with all the necessary information for military operations, is a consequence of the development of guided air-to-surface missiles as a new class of high-precision weapons. One of the first such sighting systems, called “Kaira” (Mikoyan, Gurevich MiG-27, “Corner of the Sky”, 2009) [2], used the laser aiming method. When using it, the pilot must keep the rocket after launch in the field of view and in the range of the beam until it hits the target in conditions when it is necessary to perform anti-aircraft maneuvering, which increases the load on the operator. In addition, the use of a radio beam for the automatic detection and tracking of an inconspicuous target, as is realized for airborne targets, was not possible due to the low radio contrast of the target against the background of the terrain, where target detection in difficult weather conditions is complicated by folds of the terrain and masking vegetation.

The use of new technologies, microelectronics and optical-electronic equipment, the use of the principles of television target tracking with a laser target designation channel ensured the further development of OPS. In this case, the search for the target was carried out using the daily television channel. The typical target of the Kaira tank was capable of detecting from a distance of up to 5 km. The television channel Kayry was connected to a laser rangefinder, which measures the distance to the target and illuminates it with a laser beam. Having discovered the target and performing its target designation operation, the pilot provided the system with synchronous coordinate reference of the laser beam to the object of attack. The missile is aimed at a target illuminated by laser radiation using a digital computer using a specially developed program (software-corrected tracking (PCS)), which takes into account the direction of the beam, the speed of the rocket, and the movement of the carrier.

Subsequent tests showed that the PCS mode was ineffective. The computer complex, due to its limited speed and lack of algorithms, did not have time to track the movement of the target during aircraft maneuvers. To achieve accurate retention of the crosshairs on the target, the pilot has to adjust the guidance.

Currently, work is underway in the leading countries of the world to improve the optical and optoelectronic coordinators, thermal imaging and radar homing heads (GOS), as well as correction devices for tactical missile control systems, which inevitably affects OPS. In modern systems, the OPS performs the search, detection and tracking of targets by their thermal radiation from any angle of the target against the background of the earth and the water surface in the daytime and at night, in the presence of organized interference, it measures the distance to the targets with a laser rangefinder.

A known method of aiming in a combined homing with a semi-active laser, thermal imaging and active radar channels, which is intended to equip a promising UR JCM, designed for attack helicopters type AH-64D Apache Longbow and OH-58D [3]. The complex implements a method of aiming and pointing over a fiber optic communication line (FOCL). In this case, a heat television camera is installed on the rocket, from which the observed image is transmitted to the OPS operator on the carrier and it controls the rocket. Structurally, the optoelectronic block of the GSN receivers and the radar antenna are made in a single servo system, which ensures their separate or joint operation in the guidance process. In the GOS, the principle of combined homing is implemented depending on the type of target (contrast in the visible region of the spectrum, contrast in the thermal region of the spectrum or radio contrast) and application conditions, according to which the optimal guidance method in one of the GOS operation modes is automatically selected, and the rest are used for forming a contrast display of the target when calculating the aiming point. An illustration is the Spike-ER complex (Israel), designed to destroy armored and other nomenclature targets at short ranges and placed on attack helicopters AN-1 Cobra, SA 330L Puma, etc. [4]. The effective range of the complex is 8 km, the maximum flight speed of the rocket is 180 m / s, the average is 160 m / s, the flight time of the rocket is 8 km is 50 s, the probability of hitting a tank-type target is 0.6-0.7 .

The specified complex contains an OPS with a thermal television sight, an information display system (video monitors), a computer, a control panel for the complex and a launcher with missiles, as well as a thermal television GOS, an electronics unit, a steering gear and a FOCL coil located on the rocket. The complex uses two missile control modes: autonomous homing in case of capturing the target's GOOS before launch and combined manual control over the FOCL with the participation of the operator (in the absence of capturing the target's GOOS before launch) during subsequent capture of the target's GOOS and homing at the final section.

The main disadvantages of the aiming complex, due to the methods of aiming and guidance incorporated in it, are:

- volley firing of missiles at several targets at ranges of more than 4-5 km is not provided due to manual guidance by the operator of the missile at the fiber optic link;

- not provided effective shooting at moving ground targets at long ranges due to the low speed and long flight time of the rocket;

- the presence of manual guidance with the participation of the operator requires a significant reduction in the speed of the rocket, while the likelihood of a helicopter hitting the enemy with air defense increases.

As an example of the guidance complex, where FOCL control is not used, we can mention the "helicopter complex of high-precision short-range weapons" (invention (19) RU (11) 2351508 (13) C1) [5], in which the aiming and guidance of the rocket is through control of the laser beam from the laser beam unit installed in the OPS, and controlled by the operator during the entire guidance phase.

The last decade has been marked by a deep penetration into modern guided weapon guidance systems of the “let go and forget” principle, in which, after a missile is launched, the latter is automatically aimed at the target without operator intervention, and the carrier is free in its actions. The implementation of this principle has been embodied, first of all, with the introduction of passive telethermovision homing systems, which today have the best spatial resolution characteristics, thereby ensuring high accuracy of hitting the target. For the first time, such systems were used in organizing the missile launch process (AGM-114 Hellfire and AGM-65 Maverick, [6]) in the so-called “under-wing” aiming method, in which the operator directly controls the line of sight tele-thermal imaging systems, according to the image received from its sensor at the time of launch. In this case, the operator, when a potential target is detected by the OPS, controls the gyrostabilized platform of the rocket through the control panel so that the line of sight (optical axis) of the heat and television camera mounted on the platform of the gyro coordinator of the rocket is aimed at the target. The image from the camera is transmitted to the OPS monitor and allows the operator to carry out target designation and transfer the missile auto-tracking system to the target auto-tracking, and only then can the missile be launched.

As a prototype for comparison with the claimed adopted method of aiming "from under the wing." The produced sequence of operator actions has obvious disadvantages, which is due to a number of objective factors. The characteristics of the thermal television sight of the OPS (angle of view, the format of the photodetector of its camera) have better values than the characteristics of the thermal television camera mounted on a rocket. This is due to the fact that in order not to enter the affected area, the OPS must have a sophisticated high-precision optical system for detecting targets at extreme ranges. However, such an optical system, due to its overall characteristics, cannot be installed in a rocket. If, however, we take into account that there is always a discrepancy between the direction vectors of the axes of the optical systems of the OPS and the rocket, due to instrumental errors in the alignment of both optical systems, errors in the angle sensors, mechanical vibrations of the missile suspension sites, etc., then targeting in the image only from the OPS is inevitable leads to erroneous capture of the target and the final miss. To avoid this, the operator must carry out target designation from the image from the heat-television camera mounted on the rocket, leading to an increase in time to capture the target and a decrease in the working range, which, in the end, is equivalent to increasing the likelihood of a helicopter hitting air defense systems.

The proposed method of automating aiming is designed to eliminate these shortcomings, ensures the accuracy of target designation and high accuracy of pointing tactical missiles at stationary and moving targets while observing the “empty and forget” principle and increase the survivability of the carrier, which is achieved by the efficient use of information received from the sighting system (OPS) ) a helicopter, at the stages of aiming, launching and controlling a guided missile during its flight.

It should be noted that the proposed method works with an image obtained from any source of a video signal: from a television camera operating in the visible range, or from a thermal imaging camera operating in the middle or far infrared regions of the spectrum. Therefore, in the further description, when mentioning the heat and television signal source (as indicated in the prototype), one should consider the general view of the optoelectronic system incorporating one or another type of signal.

A method of aiming at a helicopter complex, including the formation of a target point when observing a scene image on an OPS video monitor with a thermal television sight and pointing the line of sight of the gyrocoordinator thermal imaging camera to the target using the control panel, guidance drive and information from the OPS rotation angle sensors, characterized in that

- that the operator sets the target designation point on the digital image of the scene (frame) obtained by the thermal imaging camera of the heat-television sight; in accordance with the exchange protocol, the digital image through the information exchange equipment enters the unit for creating standards for its automatic processing, taking into account the angles of the field of view and the resolution of the sensitive matrix of the cameras of the thermal sight and the thermal imaging camera of the rocket gyro coordinator (hereinafter gyro coordinator), it is compressed into a digital image used as a reference with metric characteristics that coincide with similar characteristics of the image of the gyro thermal imaging camera rdinatora;

- metric image adjustment takes into account the characteristics of the instantaneous fields of a thermal television sight R _TP and thermal imaging camera gyrocoordinator R _tkg , and is reduced to its compression by the formula:

N _et = K * N _tp ,

where N _et is the format of the generated compressed reference image,

K = (P _m * N _HGB) / (N _m * F _TAG);

R _TP - field of view of the thermal imaging camera of the sight;

R _tkg - field of view of the thermal imaging camera gyrocoordinator;

N _TP - the format of the photodetector of the sight camera;

N _tkg - format of the photodetector of the gyrocoordinator camera;

- stored compressed and a fragment of the original uncompressed digital image formed around the point indicated by the operator at the time of target designation; a compressed digital image is considered as the first reference, and a fragment of an uncompressed digital image obtained at the time of target designation as a second reference;

- the first reference image and the current image from the thermal imaging camera of the gyrocoordinator are processed by regional gradient operators to represent these images in the form of fields of brightness anomalies; the binding process is carried out, which implements the normalized cross-correlation function for searching in the current image the place corresponding to the reference compressed image (the first reference image);

- according to the coordinates of the found place, automatic target designation for the missile seeker auto tracking system is performed;

- during the flight of the rocket and automatic tracking of the target by a signal from the inertial navigation system (ANN) of the rocket, which calculates the distance to the target, at a distance when the metric characteristics of the current image received from the thermal imaging camera of the gyrocoordinator coincide with the metric characteristics of the uncompressed image from the telescopic sight stored in the memory (the second reference image), the subsequent binding process starts on the second reference image;

- for this, a second reference image is sampled from the memory; the second reference image and the current image from the thermal imaging camera of the gyrocoordinator are processed by regional gradient operators to represent these images as fields of brightness anomalies;

- the binding process is carried out, which implements the normalized cross-correlation function for searching in the current image of the thermal imaging camera of the gyro-coordinator of the target location corresponding to the second standard;

- according to the coordinates on the raster of the newly found specified target location, a new target designation and transfer of auto tracking to the specified target location are performed.

In fig. 1 presents a block diagram of the proposed method, containing the main functional blocks illustrating the sequence of necessary actions for its implementation.

The following notation for functional blocks is introduced:

1 - Survey and sighting system (OPS), consisting of:

2 - thermal television sight

3 - video monitor

4 - control panel

5 - drive

6-angle sensors

7 - Information exchange equipment

8 - Block forming standards

9 - Memory 1

10 - Memory 2

11 - Block conversion and signal processing

12 - Correlator

13 - Gyrocoordinator, consisting of

14 - gyrostabilized drive

15 - thermal imaging camera

16 - fairing

17 - Auto tracking system

18 - Information Navigation System (ANN)

The proposed method of aiming is implemented as follows. The OPS operator of the helicopter, observing on the monitor (3) the scene visible through the heat-television sight (2) containing the narrow-field optical system, searches for the target. When a target object is detected, the operator, using the control panel (4) and the coupled drives (5), directs the axis of the sight line of sight to the target. The data read from the angle sensors (6) of the spatial position of the sight line of sight are fed to the gyro-stabilized drive (14) of the gyrocoordinator (13), which orientates the axis of the line of sight of the wide-angle thermal imaging camera of the rocket (15) towards the target. However, this direction, as noted above, differs from the direction that the thermal imaging sight provides. The resulting error does not allow reliable capture of small targets. In addition, when operating at extreme ranges, a small-sized target may not be visible in the image from the wide-angle thermal imaging camera of the rocket. Therefore, the digital image of the scene (frame) obtained by the thermal imaging camera of the thermal television sight with the coordinates of the target designation point set by the operator, in accordance with the exchange protocol via the information exchange equipment (7), is supplied to the unit for generating standards (8) for its automatic processing. From the received digital image, a region around the point indicated by the operator at the time of target designation is selected and stored in memory 2 (10) as a second reference image. In addition, a compression operation is performed with this image in order to reduce its metric characteristics to the metric characteristics of the thermal imaging camera of the gyrocoordinator. For this, the characteristic values of the instantaneous fields of both cameras are used.

The compression ratio K is defined as

K = R _mp / R _tkg = (P _tp * N _tkg ) / (N _tp * P _tkg );

Then the format N _{et of the} generated compressed reference image is determined by the formula

N _et = K * N _tp ,

The compressed image is considered the first reference and stored in memory 1 (9). The first reference image, extracted from memory 1, and the current image from the thermal imaging camera of the gyrocoordinator, obtained at the time of target designation, are sent to the signal conversion and processing unit (11), where, using regional gradient operators, these images are represented as fields of brightness anomalies. The subsequent operation is processing in the correlator (12), where the binding process is implemented that implements the normalized cross-correlation function. As a result of the actions, a search is performed in the current image for the place that best matches the first reference image, in the center of which is the target object indicated by the OPS operator.

According to the coordinates of the found place, automatic target designation is performed for the auto tracking system (17) for the purpose, according to the control signals from which, during the subsequent flight, the gyro-stabilized drive (14) of the gyrocoordinator (15) is controlled and the flight of the rocket is corrected.

During the flight of a rocket, information on the range to the target object is read from the airborne information-navigation system (ANN) (18). At a distance when the metric characteristics of the current image received from the thermal imaging camera of the gyrocoordinator coincide with the metric characteristics of the uncompressed image from the telescopic sight recorded in memory 2 (the second reference), another binding process is started.

The second reference (uncompressed) image is extracted from memory 2. The second reference image and the current image from the gyrocoordinator's thermal imaging camera are sent to the signal conversion and processing unit (11), where they are processed by regional gradient operators to represent these images as fields of brightness anomalies. The subsequent operation is their processing in the correlator (12), where the binding process is implemented that implements the normalized cross-correlation function and implements a new snap process for correcting the target designation point. Based on the coordinates of the newly found specified location, new target designation is performed and auto tracking is transferred to the specified target designation point corresponding to the target designation of the operator at the time of aiming. The control signals generated in this way correct the direction of the line of sight of the gyrocoordinator and the direction of flight of the rocket.

1. Guided missile guidance method (RF patent No. 2436031)

2. Mikoyan, Gurevich MiG-27, "Corner of the sky", 2009

3. "Foreign Military Review" No. 1, 2006, pp. 40-44.

4. Military Technology, 1998, No. 4, pp. 26-28; Compendium by Armada, Anti-Armor Weapons, 2000, pp. 1-30.

5 Helicopter complex of high-precision short-range weapons invention (19) RU (11) 2351508 (13) C1

6. Dmitriev V. "Guided missile" Maverick "with a thermal imaging homing head, Foreign Military Review, N3, 1983

Claims (1)

The method of aiming at a helicopter complex, which consists in the fact that the target designation point is set by the operator according to the image observed by him on the monitor of the sighting system (OPS) with the optoelectronic system (OES) of the sight, operating in the visible, middle and far infrared regions of the spectrum, the operator electronically captures the target and transfers the function of subsequent tracking to it to the auto tracking system for the target using the image from the ECO of the camera mounted on the gyro-coordinator of the rocket having the values of the field of view angle and resolution of the camera’s sensitive matrix is different than the values of these characteristics for the SEC of the sight, characterized in that a fragment of the image around the target designation is cut out and stored from the digital image of the scene with the SEC of the target, and the full digital image of the scene with the SEC of the sight is compressed to match the metric characteristics of the SEC of the sight and the gyrocoordinator cameras, the fragment and the compressed image are processed by the regional gradient operator, received from the ECO of the image camera, are also processed by the same using a compressed and processed image from the sight, the regional gradient operator uses it to compare it with the uncompressed image from the camera’s OES using the normalized cross-correlation function to find the target point on the camera’s OES image, the coordinates of the found point are transmitted to the auto tracking system for further tracking of the target, at a distance when the metric of the memorized fragment coincides with the metric of the current image from the ECO of the gyrocoordinator camera, repeated rmirovannaya cross-correlation of this fragment with a certain image region (the gradient operator) about the current tracking point for its correction.

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