EP0597233B1 - Method of producing a decay object - Google Patents

Description

The invention relates to a method for providing a dummy target body after the introduction of claim 1.

Such a method is known from DE-A-3 311 530, in which the dummy target body, which is intended to emulate a ship-like target signature, is brought into its position outside the watercraft to be simulated by means of an underwater vehicle. The disadvantage here is that the apparent target body must be built up by means of a corresponding single active mass and thus the spatial signature only in most distant and can be achieved without a temporal stabilization. In addition, a spatial-spectral distribution of the active mass is excluded. A similar prior art is also shown in EP-A-240 819.

In addition, it is known to use simple, hot pyrotechnic interference emitters as dummy targets for aircraft, armored vehicles and ships for the purpose of deceiving IR target seekers, the IR dummy targets being approximated to a certain extent (area size, spectral radiation components) and how are known from DE-A-3 421 734, possibly depending on the time, by gradually using a plurality of active masses which are successively to be laid, to be moved away from the object to be protected.

The following IR deception principles are currently used worldwide: Burning off fuel, pyrotechnic active materials with metallic components (e.g. magnesium / polytetrafluoroethylene), pyrotechnic active materials on carrier materials (flares) and "warm clouds", generated by an exothermic chemical reaction. All of these principles have the common disadvantage that they create points in the infrared or, at best, structureless clouds that have nothing in common with the contour and IR signature of a military object. The consequence of this fact is that these deceptive principles against "intelligent" imaging seekers, in particular IR seekers, of the so-called third generation are completely ineffective.

The simulation of a two-dimensional spatial and spectral target signature of the object by a corresponding number and positioning of active masses is already known from WO-A-90/04750, whereby also by such measures, however, cannot be sufficiently effectively distracted by "intelligent" homing heads.

The invention has for its object to provide a method of the type mentioned, by means of which objects, such as ships, can be effectively protected against object contour sensitive "intelligent" seekers with spectral differentiation.

According to the invention, this object is achieved by the combination of the features of claim 1.

Particular embodiments of the invention are the subject of the dependent claims.

The invention is based on the surprising finding that it is possible to use a method, which is suitable in principle for all conceivable objects, for protection against imaging target seekers thereby to indicate that in particular computer-controlled under essentially continuous monitoring of the three-dimensional dummy target body active masses, for. B. in the form of rapid-fire ammunition relatively small caliber, so spatially or temporally offset at the location of the dummy target to be assembled for disassembly that the target signature of the object to be protected in "deceptive similarity" for imaging target seekers, such as IR heads, is simulated. Different active masses are preferably used in this way, in this way differently warm surfaces of the object to be protected, e.g. B. the fuselage on the one hand and the fireplace or chimneys on the other hand of an object to be protected. such as B. a destroyer, an ammunition transport or the like, with different spectral attractiveness for the target seeker, so that the most realistic simulation of the object to be protected is achieved in this way.

Fig. 1.

eine IR-Zielsignatur eines als zu schützendes Objekt gedachten Zerstörers;

Fig.2

ein dreidimensionales IR-Scheinziel des Zerstörers gemäß Fig.1, erzeugt mittels des Verfahrens nach der Erfindung,

Fig.3

einen herkömmlichen Scheinzielkörper zusammen mit einer Zerstörer entspreshend Fig. 1;

Fig. 4

eine IR-Zielsignatur eines als zu schützendes Objekt gedachten Munitionstransporters;

Fig. 5

ein dreidimensionales IR-Scheinziel des Munitionstransporters von Fig. 4, erzeugt nach dem erfindungsgemäßen Verfahren;

Fig. 6

die graphische Darstellung der spektralen Strahldichte eines Schwarzkörperstrahlers mit einer Oberflächentemperatur von 40°C; und

Fig. 7

die graphische Darstellung der spektralen Strahldichte eines Schwarzkörperstrahlers mit einer Oberflächentemperatur von 100°C.

Further features and advantages of the invention result from the following description, in which exemplary embodiments are explained in detail with reference to the drawings. It shows:

Fig. 1.

an IR target signature of a destroyer intended to be protected;

Fig. 2

a three-dimensional IR apparent target of the destroyer according to Figure 1, generated by means of the method according to the invention,

Fig. 3

a conventional dummy target body together with a destroyer corresponding to Fig. 1;

Fig. 4

an IR target signature of an ammunition transporter intended to be protected;

Fig. 5

a three-dimensional IR dummy target of the ammunition transporter of Fig. 4, produced by the method according to the invention;

Fig. 6

the graphical representation of the spectral radiance of a blackbody radiator with a surface temperature of 40 ° C; and

Fig. 7

the graphical representation of the spectral radiance of a blackbody radiator with a surface temperature of 100 ° C.

As can be seen in FIG. 1, the IR signature of the destroyer 10 shown there has a fuselage area with a relatively uniform surface temperature and two "hot spots" in the form of two chimneys 12, 14.

FIG. 2 shows that, according to the method according to the invention, a dummy target body 10 'has a "fuselage part" with an essentially uniform surface temperature and two "hot spots" 12', 14 ', corresponding to the chimneys 12, 14 of FIG. 1. The three-dimensional IR apparent target according to FIG. 2 has a specific similarity to the destroyer according to FIG. 1 for an “intelligent” IR seeker head, that the seeker head will attack the dummy target body instead of the destroyer if the overall apparent target is achieved by appropriate beam strengths and / or beam densities etc. is made more attractive to the seeker than the destroyer.

Figure 3 shows a destroyer with the conventional dummy target (torch) 11 without an object-like contour, so that this is not the real object, i.e. a third-generation "intelligent" IR seeker head. the destroyer 10 will be preferred.

Similar results from a comparison of FIGS. 4 and 5, FIG. 4 showing an ammunition transporter 16 with a single chimney 18. Accordingly, there is IR dummy target, shown according to the invention, again according to FIG. 5, a dummy target body 16 'with a single "hot spot"18'.

The invention has been explained above on the basis of the exemplary embodiments shown for the most common application, the protection of ships, but designs for other objects are only available in nunition caliber and ammunition composition, each of which must be optimized for the respective contour and spatial-spectral IR signature. differentiate. The specific IR criteria of the object to be protected (shape, area size, spatial spectral radiation distribution, movement behavior) are reproduced true to the original according to the invention. At the same time, the radiance of the dummy target body is increased compared to the object in order to represent the more attractive target for the IR seeker head. The faithful, three-dimensional replica also has the advantage that the invention creates a dummy target body, which is effective for all threats and therefore for several simultaneous attacks from different directions.

In the case of IR dummy target bodies (of course, the principle of the invention can also be used for, for example, radar-controlled target seekers, sound-controlled attack bodies, etc.), according to the method according to the invention, a three-dimensional dummy target can be achieved by the rapid and continuous targeted firing of specific pyrotechnic active substances under the following Realize basic principles: firing sequence with high cadence, e.g. B. with more than three shots / sec., Small caliber, ie approx. 40 mm and smaller (possible use of rapid-fire grenade launchers), use of two or more pyrotechnic IR active materials with different, object-like spectral radiation characteristics, and finally control of the application in the simplest case manually, but better by a computer, whereby the inclusion of the digital image processing of a thermal imaging device at the point of firing generates the IR apparent target according to a predetermined pattern and can be maintained by continuous approaching pyrotechnic active materials. By successively shifting the direction of application, a movement (travel) of the apparent target can be effected, in the sense of DE-OS 34 21 734.

A sequence of shots with a high cadence is expedient when carrying out the method according to the invention in order to repair defects in the IR pattern which gradually become extinguished and sink as well as defects in the IR pattern which arise as a result of wind drift, and in order to be able to build up the apparent target as quickly as possible when an IR target seeker approaches. A rate of 3 rounds / sec is required for ships. displayed in order to build up a three-dimensional apparent target with approx. 5 to 7 IR active masses in 2 seconds and to maintain it for the desired period. In general, the higher the cadence, the more accurate the IR simulation of the object.

Small calibers (approx. 40 mm and smaller) are therefore used in order to be able to produce the shape, the area and the IR target signature as true to detail as possible. In addition, small calibers offer the advantage of higher possible firing sequences. In general, the smaller the caliber, the more accurate (resolution) the IR replica of the object becomes.

The caliber size, on the other hand, limits the number of active masses (or positions) from which the apparent target is built by their burning time. It is Z. B. not possible to build a homogeneous apparent target if the The effective duration (= burning time) of a position (= an effective mass = one storey) is about 3 seconds, but due to the specified cadence it can only be replenished after 4 seconds.

• (3) K : Kadenz in Schuß pro Sekunde
• (4) B : Wirkdauer der Wirkmasse in Sekunden
• (1) Z : Maximal mögliche Positionen (= Wirkmassen) des Scheinziels einer Schußfolge
• (5) n : Schußfolge (n = 1 entspricht dem Aufbau des Scheinziels, n = 2 entspricht dem 1ten Nachnähren, n = 3 dem 2ten Nachnähren usw.)
• (6) m : Positionskennzahl der Wirkmasse im Scheinziel
• (2) t_n,m : Zerlegungszeit der Wirkmasse auf position m in der Schußfolge n nach der ersten Zerlegung
• (7) Δ t : Zeit zwischen den Zerlegungen auf einer Position

Für die maximale Zahl der Wirkmassen einer Schußfolge gilt folgender Zusammenhang:

Beispiel : $${\text{K = 4 s}}^{\text{-1}}\text{· B = 3s}$$

$${\text{Z = 4 s}}^{\text{-1}}\text{· 3 s = 12}$$

The following applies to the following calculation:

• (3) K: Cadence in shots per second
• (4) B: duration of action of the active mass in seconds
• (1) Z: maximum possible positions (= effective masses) of the apparent target of a sequence of shots
• (5) n: sequence of shots (n = 1 corresponds to the structure of the dummy target, n = 2 corresponds to the 1st re-feeding, n = 3 the 2nd re-feeding etc.)
• (6) m: position index of the active mass in the apparent target
• (2) t _{n, m} : disassembly time of the active mass at position m in the weft sequence n after the first disassembly
• (7) Δ t: time between the decompositions at one position

The following relationship applies to the maximum number of effective masses of a firing sequence:

For example: $${\text{K = 4 s}}^{\text{-1}}\text{· B = 3s}$$

$${\text{Z = 4 s}}^{\text{-1}}\text{3 s = 12}$$

Beispiel: $${\text{K = 4 s}}^{\text{-1}}\text{B = 3 s m = 7 n = 3}$$

$${\text{t}}_{\text{n,m}}\text{=}\frac{\text{1}}{{\text{4 s}}^{\text{-1}}}\text{(7 -1) + 3 s (3 - 1) = 7,5 s}$$

für die Zeit zwischen den Zerlegungen auf einer Position gilt:

The following relationship was determined for the disassembly time of the active mass at position m in the weft sequence n after the first disassembly:

Example: $${\text{K = 4 s}}^{\text{-1}}\text{B = 3 sm = 7 n = 3}$$

$${\text{t}}_{\text{n, m}}\text{=}\frac{\text{1}}{{\text{4 s}}^{\text{-1}}}\text{(7 -1) + 3 s (3 - 1) = 7.5 s}$$

for the time between the splits in a position:

The following time table shows an example of a shot sequence: $$\text{K = 4}\frac{\text{1}}{\text{s}}\text{; B = 3 s ⇒ Z = 12 Δ t = 3 s}$$

It should also be noted that a ship (like other vehicles) does not have a homogeneous surface temperature, but rather large areas with significant temperature differences. The temperature zones most frequently recognizable on the thermal image in a ship, as the examples according to FIGS. 1 and 2 or FIGS. 4 and 5 as well as the illustration according to the prior art shown in FIG. 3 show, are the solar-heated hull (approximately 40 to 60 ° C) and the hot chimney (s) (approx. 100 ° C), which form so-called "hot spots", whereby the chimneys stand out much more strongly due to their higher temperature (corresponding to the radiance). In this case, in order to generate an IR signature true to the original, two types of active masses can be fired which have different spectral properties.

An ammunition 1 (active mass 1) is used for the spatial and spectral simulation of the ship's hull, which is explained below with reference to FIG. 6. As shown in FIG. 6, according to Planck's law of radiation or Vienna's law of displacement, the _{maximum of} radiation (λ _max ) for the spectral radiance (corresponding to temperature) of the hull is in the vicinity of λ _max = 10 µm. The active mass of the ammunition 1 should therefore generate approximately the same spectral radiance.

This can be achieved using a mixture of phosphor granules (warm smoke) and small phosphor flares in a ratio of approx. 80% (granules) and 20% (flares). This ratio is a guideline and can be adapted to the different types of ship (or other vehicles). The decomposition size of the active mass with a diameter of 10 m and more (depending on the decomposition load and the quantity of the active mass) produces the three-dimensional one Apparent target body and can be adapted to the object to be protected.

An ammunition 2 (active mass 2) is used for the spatial and spectral replication of the hot spots (chimneys), the characteristics of which are explained below with reference to FIG. 7.

As shown in FIG. 7, the radiation _maximum for this is, according to Planck's radiation law or Vienna's displacement law, for the spectral radiance of a fireplace in the range of λ _max = µm.

The active mass of the ammunition 2 is intended to produce approximately the same spectral radiance.

This can be achieved using the same substances as in the ammunition 1, but in a different mixing ratio. As a guideline, approx. 75% smaller flares with 25% phosphor granulate are used. The spatial extent is generated by the decomposition size of the active mass (⌀ 10 m or more, depending on the decomposition charge and the amount of active mass) and can be adapted to the dimensions of the object.

For other objects, several types of ammunition with varying mixing ratios of phosphor granules to flares or other active materials (two-color flares etc.) can also be used.

In the simplest case, the types of ammunition are taped (ie all on one ammunition belt) and fired from a single launcher. B.

However, it is also possible to fire two or more launchers, in which case one launcher preferably deploys only one type of ammunition.

The control of the output (shot sequence, shot direction) is carried out in the most favorable case by a computer system in connection with the digital evaluation of an own thermal imaging device. The computer control generates the dummy target pattern in accordance with the object shape and its IR signature. On the basis of the thermal image, the computer independently checks the fidelity to the original and compensates for imperfections in the pattern (due to wind drift or extinction of the active masses) by deliberately constantly reworking the apparent target.

The thermal image is checked pixel by pixel (= smallest image unit) over the entire thermal image (e.g. Barr & Stroud IR 18: 52 pixels, range 8 ... 13 µm), whereby each pixel can be viewed as a quasi-selective radiometer.

If mas treats the thermal image with digital image processing, the corresponding pixel index (= brightness value) is obtained for each pixel. This index is proportional to the radiance of the corresponding image section. If one includes the geometric data of the field of view of the thermal imaging device, the computer can determine from the image coordinates together with the associated image indices both the firing coordinates and the type of ammunition for them next firing sequences in order to optimally match the (stored) IR ship pattern in Achieve shape and spectral signature.

Depending on the current tactical situation, the computer control sets the dummy target (in the best case) between the object and the IR target seeker at a distance of approx. 50 m to 100 m from the object. The successive separation of the re-sewing and the maneuvers of the ship result in a progressive separation of the apparent target and the ship. The IR beam seeker is "pulled away" from the ship by the increased beam strength of the dummy target compared to the ship.

REFERENCE SIGN LIST

10th

destroyer

12th

Hot spot by the fireplace

14

Hot spot by the fireplace

10 '

Mock target according to invention

11

Prior art target (point target)

12 '

Hot spot through hot active mass

14 '

Hot spot through hot active mass

16

Ammunition transporter

18th

Hot spot by the fireplace

16 '

Mock target according to invention

18 '

Hot spot through hot active mass

Claims (13)

1. Method for the purpose of providing a decoy target (10', 16') which simulates the target signature of an object (10, 16), such as a land craft, an aircraft or a water craft or the like, for a target-imaging radiation-sensitive homing head, such as an infrared homing head, characterised in that effective materials, which are composed according to the spectral radiation density to be simulated and which are spatially offset in their dispersement simulating in each case a part of the target signature of the object (10, 16) by emitting radiation in different spectral patterns in the sensitive range of the target-imaging homing head, are moved into the position of the decoy target to be produced (10', 16') and dispersed there in such a manner that a three-dimensional decoy target (10', 12', 14'; 16', 18') which simulates the spectral and spatial target signature of the object for the target homing head is produced.
2. Method according to claim 1, characterised in that the effective materials are moved into the position of the decoy target (10', 16') offset with respect to time in such a manner that the three-dimensional decoy target is produced substantially continuously for a predetermined period of time.
3. Method according to claim 1 or 2, characterised in that the positioning of the effective materials is computer controlled whilst substantially continuously monitoring the decoy target (10', 16').
4. Method according to any one of the preceding claims, characterised in that the effective materials are moved into position by means of rapid-fire projectiles.
5. Method according to claim 4 characterised in that the rapid-fire projectiles are fired from a single launcher.
6. Method according to claim 4, characterised in that the rapid-fire projectiles are fired from several launchers.
7. Method according to any one of claims 4 to 6, characterised in that the rapid-fire projectiles are discharged with a frequency such that new effective material (12', 14'; 18') is dispersed substantially at each predetermined site of the effective material at the latest at the point in time in which the previous effective material extinguishes.
8. Method according to any one of claims 4 to 7, characterised in that projectiles of a calibre of a maximum 40 mm are used for the rapid fire.
9. Method according to any one of the preceding claims, characterised in that different effective materials (12', 14'; 18') are used to create regions of the decoy target (10', 16') which demonstrate different attractive characteristics to the target homing head.
10. Method according to any one of the preceding claims characterised in that infrared-active effective materials are used.
11. Method according to claim 9 or 10, characterised in that the types of effective materials used are those which comprise in each case phosphorus granulate and phosphorus flares in different ratios, wherein the first type of effective material comprises a greater portion of phosphorus granulate in order to simulate relatively cooler surfaces of objects and the second type of effective material comprises a lower portion of granulated phosphorus in order to simulate relatively warmer surfaces of objects.
12. Method according to claim 11, characterised in that the effective materials of the first type of effective material comprise approximately 80% of phosphorus granulate and approximately 20% of phosphorus flares and the effective materials of the second type of effective material comprise approximately 25% of phosphorus granulate and approximately 70 % phosphorus flares.
13. Method according to any one of the preceding claims, characterised in that the effective materials are used with a dispersement area of at least 10 m.

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