Improved Guided Munition System

Abstract

The invention relates to a munition system (10) comprising: - a transport device, called cargo (DC), the cargo device comprising at least one subassembly (SE, SE1, SE2) and being configured to eject said subassembly once said area has been reached, a subassembly comprising: a slowing device (DR) configured to slow the subassembly during its descent, once ejected, an analysis device (DA) of an environment of said subassembly, a detection and recognition device (DTR) of said target, a guidance device (DGSE) called beacon configured to guide the subassembly and stabilize it in the vicinity of said target, once the subassembly has been ejected by the cargo device, a transmission device (DE) of a signal (SB) configured to transmit said signal once said subassembly has been stabilized in the vicinity of said target,-at least one so-called full-load munition (MPC) comprising a guidance device (DGM) called munition configured to guide said munition on said signal (SB). Figure 3,

Description

Title of invention: Improved guided munition system FIELD OF THE INVENTION

[0001] The present invention relates to a munition system allowing precision artillery fire to be carried out in a harsh environment. STATE OF THE ART

[0002] To ensure dominance of fire over the enemy, artillery seeks to increase its range and strike accuracy. Precision is achieved by the use of guided munitions, capable of correcting their trajectory.

[0003] In existing solutions, a first mode of guidance is based on the exploitation of satellite positioning signals (GNSS). The munition, knowing its coordinates and exploiting the satellite positioning signals, heads towards the target whose coordinates were previously recorded during the mission preparation phase. An example of a munition of this type is the Excalibur artillery shell (155 mm) developed by the Raytheon company (USA). Another example is the Precision Guidance Kit (PGK) from Northrop Grumman, also for 155 mm.

[0004] A second guidance mode is based on laser designation. The target is pointed at by a third party with a laser (often carried by an aircraft, a drone, or special forces in contact), the munition being equipped with a laser designation kit allowing it to detect the light spot emitted by the target illuminated by the laser (laser spot) and to control its trajectory to reach the laser spot. Such kits integrate photoreceptors (4Q, mosaics, matrices) allowing the difference between the axis of the munition and the laser spot to be measured. A first example is the APKWS kit from BAE Systems for a 70 mm rocket, and a second example is the SAL kit on Leonardo's Vulcano munition (155 mm).

[0005] In a context of high intensity conflict, electromagnetic jamming, also called a "GNSS denied" environment, and the difficulty in flying over or approaching the adversary defeat these guidance modes.

[0006] Ideally, the munition should be given an autonomous scene analysis capability so that it can find the target designated for it in the mission preparation phase. A munition equipped with an imager and an image processing chain (geo-referencing, target detection & recognition) could be capable of analyzing an area on the ground, locating the target there and guiding itself to it.

[0007] An example of such a fully autonomous munition 11, called “imaging”, is illustrated [Fig.l].

[0008] The munition 11 comprises a tail 12, an explosive charge 13 occupying the “rear” part of the munition, the volume of which is sought to be maximized in order to maximize the military effect, but subject to the constraints of the caliber and volume required for the other elements, a GNSS receiver 14, flight actuators 15 (canard) allowing it to modify its trajectory according to guidance orders, a deviation meter 16 comprising the imager, the image processing chain and a computer, and an ejectable fairing 17.

[0009] However, the technical challenges to achieve the production of such ammunition are very significant, in particular on the following themes:

[0010] Compactness: a full military load and the flight actuators leave a very limited volume for the terminal guidance kit / deviation meter: the volume allocated to the “intelligent” part is small.

[0011] The very short time sequence between the moment when the guidance kit is able to make an image, once the munition has descended below the cloud layer and at a ground distance corresponding to a photometric assessment allowing the production of an image. It is necessary to detect sufficient photons despite the modest entrance pupil size, imposed by the front geometry of the munition. During this very constrained time range of 2 to 3 s, the image processing chain must analyze the area, recognize the target and allow the development of guidance orders. One consequence is the need for high computing power.

[0012] The quality of the images acquired in flight, in particular if the munition is in autorotation.

[0013] Full military-grade ammunition incorporating an optical guidance chain will probably not be available for about ten years.

[0014] Furthermore, there are munitions containing reduced military charges (as opposed to the full charge) whose kinematics are specific, an example of which is shown diagrammatically [Fig.2] (155 mm artillery shell called Bonus from BAE Systems and Nexter). The munition 20 comprises a so-called "cargo" part 22 which is configured to transport, to the area in which a target is located, sub-assemblies 21 which are ejected once they arrive in the area. It also comprises a trigger fuse 24 which determines the moment at which the sub-assembly must be ejected by the ejection device 23. These sub-assemblies 21 have, once ejected, a slowed descent (parachute, fins), they analyze the area, detect the target and direct their charge towards the target (via steerable flight actuators such as rotary wings or steerable fins). Such ammunition is limited to targets such as armored vehicles requiring only a small (formed) charge.Another example of this type of ammunition is the Smart 155 shell manufactured by Rheinmetall and Diehl (Germany).

[0015] In summary: - Existing solutions (GNSS or SAL guidance) are not adapted to the high intensity context, - The long-term solution (image processing chain integrated into a fully loaded munition) will take time to become available due to its technical complexity, - The small-load solution, in cargo ammunition, is limited to a restricted family of targets.

[0016] An aim of the present invention is to remedy the aforementioned drawbacks by proposing a munition system comprising two different elements which cooperate, this cooperation making it possible to produce a munition carrying a full explosive charge guided to the target, without it integrating a complex processing / guidance chain. DESCRIPTION OF THE INVENTION

[0017] The present invention relates to a munition system comprising: - a transport device, called cargo, configured to reach and fly over an area comprising at least one target, the cargo device comprising at least one subassembly and being configured to eject said subassembly once said area has been reached, the subassembly comprising: • a slowing device configured to slow the subassembly during its descent, once ejected, • a device for analyzing an environment of said subset, • a device for detecting and recognizing said target, • a guidance device called a beacon configured to guide the subassembly and stabilize it near said target, once the subassembly has been ejected by the cargo device, • a signal emitting device configured to emit said signal once said subassembly has stabilized near said target, - at least one so-called full-load munition configured to reach and fly over said zone independently of the cargo device, and comprising a guidance device called munition configured to guide said munition on said signal.

[0018] According to one embodiment, the cargo device has a shell or rocket type structure without explosive charge. According to another embodiment, the cargo device has a missile or bomb type structure without explosive charge. According to yet another embodiment, the DC cargo device is a drone.

[0019] According to one embodiment, the device for analyzing the subset is chosen from: a visible or infrared imaging device, a radiofrequency imaging device, a lidar.

[0020] According to a first embodiment, the emission device is configured to emit an optical signal, and the munition guidance device is configured to use an optical task in a given wavelength range.

[0021] According to a second embodiment, the emission device is configured to emit a signal generated by a pyrotechnic composition.

[0022] According to a third embodiment, the transmission device is an antenna configured to transmit a radiofrequency signal.

[0023] According to a variant, the cargo device and the fully loaded munition have an identical structure in order to be adapted to the same type of launch system to be sent to said zone.

[0024] According to one embodiment, the cargo device comprises at least a first and a second subassembly, the zone comprising at least a first and a second target, said first and second subassembly being configured to stabilize in the vicinity of the first and second target respectively. In addition, a first and a second transmission device associated respectively with the first and the second subassembly are configured to transmit respectively a first and a second signal. The munition system further comprises at least a first and a second fully loaded munition, the first and second munition guidance devices of which are respectively configured to be guided on the first and the second signal respectively.

[0025] According to another aspect, the invention relates to a method for destroying a target with a munitions system comprising the steps of: A sending a transport device, called a cargo, overflying an area comprising at least one target, the cargo device comprising at least one sub-assembly, B sending at least one so-called full-load munition overflying said area independently of the cargo device, C dropping or ejecting said sub-assembly once said area has been reached and slowing down said sub-assembly during its descent, D analyzing an environment of said ejected sub-assembly, detecting and recognizing said target in the environment with an analysis device specific to said sub-assembly E guiding the sub-assembly towards the target and stabilizing it in the vicinity of said target with a guidance device, called a beacon, specific to said sub-assembly, F emitting a signal once said sub-assembly has been stabilized in the vicinity of said target,with a transmission device specific to said subassembly, G guide said full-load munition on said signal with a guidance device called munition specific to said full-load munition.

[0026] According to one embodiment, steps A and B are implemented so that the fully loaded ammunition reaches the area once the signal is emitted in step F.

[0027] According to one embodiment, the cargo device is an uncharged shell, the fully charged ammunition is a shell, and steps A and B are implemented by one or two guns adapted to launching said shells.

[0028] The following description presents several exemplary embodiments of the device of the invention: these examples are not limiting of the scope of the invention. These exemplary embodiments present both the essential characteristics of the invention as well as additional characteristics linked to the embodiments considered.

[0029] The invention will be better understood and other characteristics, aims and advantages thereof will appear during the detailed description which follows and with reference to the appended drawings given as non-limiting examples and in which:

[0030] The [Fig. 1] already cited illustrates an imaging munition of the future.

[0031] The [Fig.2] already cited illustrates a low-charge guided munition.

[0032] [Fig.3] illustrates the ammunition system according to the invention.

[0033] [Fig.4] illustrates an embodiment of the invention in an operational context, with two subassemblies, two targets and two ammunitions.

[0034] [Fig.5] illustrates steps A (left diagram) and B (right diagram) of the method according to the invention.

[0035] [Fig.6] illustrates on the left diagram steps C and D and on the right diagram steps E and F of the method according to the invention.

[0036] [Fig.7] illustrates step G of the method according to the invention. DETAILED DESCRIPTION OF THE INVENTION

[0037] The idea behind the ammunition system 10 according to the invention consists of splitting the problem into two parts, resulting in a tandem of two complementary elements, each being optimized for a function. A first element without explosive charge performs an area analysis and target recognition and a second element is a munition carrying a complete military charge, the guidance of which is facilitated by a "beacon" deposited by the first element. At the operational level, a coordinated firing of the first element, "munition" without explosive charge, is carried out, followed by the full charge munition which reaches the target thanks to guidance by the beacon.

[0038] The ammunition system 10 according to the invention, a “kit” of two elements, is illustrated [Fig. 3]. It comprises a transport device called cargo DC configured to reach and fly over a zone ZN comprising at least one target TA. The cargo device comprises at least one subassembly SE and is configured to eject the subassembly once the affected zone ZN has been reached. The cargo device DC does not carry any military load.

[0039] According to one embodiment, the DC cargo device has a shell or rocket type structure, as in the Bonus type ammunition. In the case of a shell the trajectory to the area is ballistic type, in the case of a rocket the ballistic trajectory is improved by steerable flight actuators.

[0040] According to another embodiment, the DC cargo device has a missile type structure (own propulsion) or bomb type (without explosive charge).

[0041] According to yet another embodiment, the cargo device DC is a drone.

[0042] The mission of the cargo device is to drop the subassembly SE onto the area.

[0043] The subassembly SE comprises a slowing device DR configured to slow it down during its descent, once ejected, an analysis device DA of the environment of the subassembly, typically in front of it and a detection and recognition device DTR of the target. It also comprises a guidance device DGSE called a beacon guidance device, configured to guide the subassembly SE and stabilize it in the vicinity of the target, once the subassembly SE has been ejected by the cargo device DC and the target has been located by the device DTR. Positioning on the target can be carried out via the air and possibly on the ground. Finally, the subassembly SE comprises a transmission device DE of a signal SB configured to transmit the signal SB once the subassembly has been stabilized in the vicinity of the target. The transmission of the signal SB is activated once SE is positioned close to the target.

[0044] The munition system 10 also comprises at least one so-called full-load munition MPC configured to reach and fly over the ZN zone independently of the cargo device. The full-load munition MPC obviously comprises a military charge CM, and also comprises a DGM guidance device called a munition guidance device, configured to guide the full-load munition on the SB signal. The MPC DGM munition guidance device is adapted to the emitted SB signal.

[0045] Thus the SE subassembly, once positioned close to the target, acts as an impact wish “beacon”, having the function of guiding the fully loaded ammunition onto the target.

[0046] Thus the ammunition system according to the invention is composed of two cooperating elements, one specialized in target search and the other is a "simple" charge-carrying ammunition. The ammunition system according to the invention allows high-precision full-charge artillery strikes compatible with mature technologies available today.

[0047] Operationally, it is appropriate for the cargo device to arrive first in the area, with the fully loaded ammunition arriving afterwards, once the subassembly has been ejected and placed near the target.

[0048] According to one embodiment, the full-load MPC munition is of the shell or rocket type. According to another embodiment, the full-load munition is of the bomb type, and according to another embodiment, the full-load munition is of the missile. These munitions are equipped with a guidance device adapted to their nature and to the beacon (SB signal) used. They can be conventional (see below).

[0049] A fully loaded munition is associated, via its guidance device, with a given subassembly, i.e. a given transmission signal.

[0050] In one embodiment, there are several MPC munitions associated with a given subset, to maximize the probability of destruction of the target.

[0051] In a preferred variant the cargo device DC comprises N sub-assemblies, typically two, i.e. at least a first sub-assembly SE1 and a second sub-assembly SE2, as illustrated [Fig.4] in an operational context.

[0052] A multiplicity of subsets implies a multiplicity of MPC munitions, each munition being configured to be guided on one of the subsets, typically by a specific coding of the SB signal.

[0053] In a first embodiment, the zone ZN comprises only a single target and the different sub-assemblies are guided onto this single target, the multiplicity of sub-assemblies and associated munitions maximizing the probability of destruction of the target.

[0054] In a second embodiment, the zone ZN comprises several targets, namely at least a first target TA1 and a second target TA, and the subassemblies SE1 and SE2 are configured to stabilize in the vicinity of the first and second targets respectively. Thus, each subassembly is associated with a target. For the associated munitions, discrimination between the targets is carried out by coding the emitted signal. Thus, the subassembly SE1 comprises a first transmission device DE1 configured to transmit a first signal SI, and the subassembly SE2 comprises a second transmission device DE2 configured to transmit a second signal S2. This is typically a signal of the same nature (see below) having a specific coding.

[0055] The munition system also comprises at least a first full-load munition MPC1 comprising a first munition guidance device DGM1 and a second full-load munition MPC2 comprising a second munition guidance device DGM2. The first munition guidance device DGM1 is configured to be guided on the first signal S1 and the second munition guidance device DGM2 is configured to be guided on the second signal S2 as illustrated [Fig.4].

[0056] Once the subset SE1 is located near TA1, it emits the signal SI in order to guide MPC1 to TA1 via DGM1. Similarly, once the subset SE2 is located near TA2, it emits the signal S2 in order to guide MPC2 to TA2 via DGM2.

[0057] A combination of the two aforementioned modes is also possible with several munitions associated with a given subset, and several subsets, a subset being associated with a target (therefore several targets).

[0058] According to one embodiment, the cargo device and the fully loaded ammunition have an identical structure in order to be adapted to the same type of launch system to be sent to the zone. For example, it may be artillery ammunition of the shell type adapted to firing with a 155mm cannon or other. The cargo device then has the structure of a shell without a military charge and the ammunition of a conventional shell with guidance. They can be fired sequentially, first the cargo device then the ammunition, or simultaneously. In the latter case, the arrival in the zone of the cargo device before the arrival of the ammunition is obtained by differentiating the trajectories.

[0059] Both types of shells (cargo and ammunition) can be fired by the same gun, or by two guns from the same firing battery.

[0060] According to one embodiment, the DA analysis device of the SE subassembly is chosen from: a visible or infrared imaging device, a radiofrequency imaging device, a lidar.

[0061] The beacons, i.e. the DE emission devices of the SE subassemblies, may be active or passive. They must constitute an easily detectable marker (and suitable for deviation measurement) for the DGM ammunition guidance device of the associated munitions.

[0062] According to one embodiment, the emitted signal is an optical signal (light beacon), visible or infrared. Typically, the emitting device DE is chosen from an LED, a laser diode or a laser.

[0063] Preferably, the DGM munition guidance device is configured to use an optical task in a given wavelength range, including the case of a single wavelength.

[0064] This may be, for example, a four-quadrant homing device on an optical spot. An example is a four-quadrant device detecting the near IR (typically 1.06 pm), such as a semi-active laser or SAL kit known from the state of the art.

[0065] Another example is to use a low-resolution imager (typically sensitive in the visible or 1TR) to guide the munition. This imager is not powerful enough to precisely locate the target like the one used by the SE sub-assembly, but sufficiently resolved to guide the munition on a task. The choice of wavelength results from a search for optimum cost (beacon + guidance kit) and performance (attachment range, etc.).

[0066] According to one embodiment, the emitted signal is generated by a pyrotechnic composition. This is a “thermal” signal (generation of a hot spot). having a very wide spectral emission band. The associated DGM munition guidance device is for example a 4-quadrant thermal seeker (detection in the 8-12 pm band) or a low-resolution imager. Low resolution means a number of pixels typically less than 100,000 pixels. The image processing also has a simplified algorithm compared to that which would have to be implemented on a full military payload munition integrating a complex optical guidance chain (munition of the future).

[0067] According to another embodiment, the emitted signal is a radiofrequency signal typically emitted by an antenna. An associated guidance device is typically a device for identifying the direction of emission (goniometry, wavefront analysis, etc.).

[0068] An example of a passive beacon is a retroreflective beacon in the visible, infrared or radar ranges. The “emitting” device DE is here a reflector and the “emitted” signal is a signal present in the environment of the beacon and reflected by it in an angular range covering the area in which the fully loaded munition is located on approach.

[0069] According to another aspect, the invention relates to a method 100 for destroying a target with a munitions system. The different steps of the method according to the invention are illustrated in Figures 5, 6 and 7 for the case of two sets, 2 full-load munitions and two targets.

[0070] The method comprises a first step A consisting of sending a cargo transport device DC to fly over a zone ZN comprising at least one target, the cargo device comprising at least one subassembly as described previously. Then in a second step B at least one fully loaded munition MPC is sent to fly over the zone ZN independently of the cargo device. As explained above, the two steps A and B can be implemented sequentially or simultaneously. Steps A and B are illustrated [Fig.5].

[0071] During a step C the cargo device ejects the subassembly SE once the zone ZN is reached, and the ejected subassembly is slowed down during its descent. In step D the environment of the ejected subassembly is analyzed, and the target is detected and recognized in the environment with the analysis device DA specific to the subassembly. Steps C and D are illustrated in [Fig.6] on the left.

[0072] In a step E the subassembly is guided towards the target and stabilized near it with a DGSE beacon guidance device, specific to the subassembly. In a step F a transmission device specific to the subassembly transmits a signal SB, once the subassembly has stabilized near the target. Steps E and F are illustrated in [Fig.6] on the right.

[0073] In a step G illustrated [Fig.7] the full-load ammunition is guided on the signal with a guidance device called ammunition specific to the full-load ammunition.

[0074] Preferably, steps A and B are implemented so that the fully loaded ammunition reaches the area once the signal is emitted in step F.

[0075] According to one embodiment, the cargo device is an uncharged shell, the fully charged ammunition is a shell, and steps A and B are implemented by one or two guns adapted to launching said shells.

Claims

Claims

1. Munition system (10) comprising: - a transport device, called cargo (DC), configured to reach and fly over a zone (ZN) comprising at least one target (TA, TA1, TA2), the cargo device comprising at least one subassembly (SE, SE1, SE2) and being configured to eject said subassembly once said zone has been reached, the subassembly comprising: • a slowing device (DR) configured to slow the subassembly during its descent, once ejected, • an analysis device (DA) of an environment of said subassembly, • a detection and recognition device (DTR) of said target, • a guidance device (DGSE) called beacon configured to guide the subassembly and stabilize it in the vicinity of said target, once the subassembly has been ejected by the cargo device,• a device (DE) for transmitting a signal (SB) configured to transmit said signal once said subassembly has stabilized near said target, - at least one so-called full-load munition (MPC) configured to reach and fly over said zone (ZN) independently of the cargo device, and comprising a guidance device (DGM) called munition configured to guide said munition on said signal (SB).,

2. Munition system according to the preceding claim in which the cargo device (DC) has a shell or rocket type structure without explosive charge.

3. Munition system according to claim 1 in which the cargo device (DC) has a missile or bomb type structure without explosive charge.

4. A munition system according to claim 1 wherein the cargo device (DC) is a drone.

5. Munition system according to one of the preceding claims in which the device for analyzing said subassembly is chosen from: a visible or infrared imaging device, a radiofrequency imaging device, a lidar.

6. Ammunition system according to one of the preceding claims wherein the transmission device is configured to transmit a signal optical, and wherein the munition guidance device (MHD) is configured to use an optical task in a given wavelength range.

7. Ammunition system according to one of claims 1 to 6 wherein the emission device is configured to emit a signal generated by a pyrotechnic composition.

8. Ammunition system according to one of claims 1 to 6 wherein the transmitting device is an antenna configured to transmit a radiofrequency signal.

9. Munition system according to one of the preceding claims in which the cargo device and the fully loaded munition have an identical structure in order to be adapted to the same type of launch system to be sent to said zone.

10. Munition system according to one of the preceding claims wherein the cargo device comprises at least a first (SE1) and a second (SE2) subassembly, the zone comprising at least a first (TA1) and a second (TA2) target, said first and second subassembly being configured to stabilize in the vicinity of the first and second targets respectively, wherein a first (DE1) and a second (DE2) transmission device associated respectively with the first and second subassembly are configured to transmit respectively a first (SI) and a second signal (S2), the munition system further comprising at least a first (MPC1) and a second fully loaded munition (MPC2) of which respectively the first (DGM1) and the second (DGM2) munition guidance device are configured to be guided respectively on the first and second signal.

11. Method (100) for destroying a target with a munitions system comprising the steps of: A sending a transport device, called cargo (DC) to fly over a zone (ZN) comprising at least one target (TA, TA1, TA2), the cargo device comprising at least one sub-assembly (SE, SE1, SE2), B sending at least one munition called full load (MPC) to fly over said zone (ZN) independently of the cargo device, C dropping or ejecting said sub-assembly once said zone has been reached and slowing down said sub-assembly during its descent, D analyze an environment of said ejected subassembly, detect and recognize said target in the environment with an analysis device specific to said subassembly E guide the subassembly towards the target and stabilize it in the vicinity of said target with a guidance device, called a beacon, specific to said subassembly, F emit a signal once said subassembly is stabilized in the vicinity of said target, with an emission device specific to said subassembly, G guide said full-load munition on said signal with a guidance device called munition specific to said full-load munition.

12. A method according to the preceding claim wherein steps A and B are implemented such that the fully loaded ammunition reaches the area once the signal is emitted in step F.

13. A method according to either of claims 11 or 12 wherein the cargo device is an uncharged shell, the fully charged ammunition is a shell, and steps A and B are carried out by one or two guns adapted to launch said shells.

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