EP3239644B1 - An aiming-assistance method and device for laser guidance of a projectile - Google Patents

Description

The present invention is in the field of projectile guidance. It relates more particularly to the guidance of projectiles using a laser beam.

The present invention relates to a method for assisting in the targeting of a target as well as a device for assisting in the targeting of a target. The present invention also relates to a method for guiding a projectile by a laser beam using such a method of aiming assistance as well as a device for guiding a projectile by a laser beam equipped with such a device. sighting aid.

Guidance by a laser beam is used in particular by the military to guide a missile or any other projectile on a target illuminated by means of a laser beam. This technique is a semi-active autoguiding by laser designated by the acronym "SALH" designating in English "Semi-Active Laser Homing". According to this technique and as described in the document US 4143835 , a laser beam is kept pointed by an operator, often designated by the term "shooter", on a target. Reflections of this laser beam are then dispersed in a multitude of directions by reflection on the target. A projectile, such as a missile, can then be launched or dropped towards the target.

When the projectile is close enough to the target, a receiving device that the projectile comprises receives part of the laser beam reflected by the target and then determines the source of this part of the reflected laser beam, namely the target. The trajectory of the projectile is then adjusted in the direction of this source. The projectile, having no autonomous means of detecting the target proper, is then guided only towards the source by the part of the reflected laser beam which it receives.

Thus, as long as the laser beam is kept pointed at the target and the projectile guide device receives part of the reflected laser beam, the trajectory of the projectile can be corrected in order to guide the projectile exactly on the target. The emission of the laser beam is therefore dissociated from the projectile and is carried out for example by an operator. However, the operator must have the target in his field of vision in order to point the laser beam at it. Advantageously, the projectile launch zone is completely independent of the laser beam emission zone. The laser beam is emitted by a generator of a laser beam such as a laser designator.

To accurately guide the projectile towards the target, the quality of the laser beam illuminating the target is essential and is mainly based on the percentage of the laser beam actually reaching the target. A laser beam used for guiding a projectile generally consists of a succession of pulses emitted at regular or irregular time intervals, but in all cases known to be identifiable by the means for receiving the projectile.

As a result, all pulses of the laser beam not pointing at the target will guide the projectile out of the target while all pulses of the laser beam pointing at the target will guide the projectile exactly at the target.

A laser beam used for guiding a projectile can also be a continuous laser beam.

The aiming procedure always begins by scanning the environment visible to the operator in search of targets, then by stopping the scanning to focus on a target. Therefore, the operator must continuously point the laser beam at the target in order to guide the projectile towards it.

However, it can be difficult to point precisely at a target at all times, in particular when this target is mobile vis-à-vis the operator. Indeed, the target can be a moving vehicle, for example an automobile or an aircraft. The operator can also be in motion, for example being on board a rolling vehicle or else an aircraft.

In addition, the operator has no direct visual feedback on the point of the environment which is actually illuminated by the laser beam. In fact, the reflection of the laser on the target is generally not visible to the operator. The operator can therefore only rely on his aiming, carried out for example through a sighting reticle of a sighting scope for a portable laser designator or else by means of a visualization means integrated in a helmet. for a laser designator on board a vehicle. Consequently, an offset between the aiming reticle and the actual laser beam can exist and cause an aiming error which goes unnoticed by the operator. Only the impact of the projectile informs the operator about the accuracy of the initial aim and the possible aim error. In the latter case where the projectile has missed the target, the operator can possibly correct its aiming as a function of the position of the point of impact of the projectile relative to the target, but only after a first failure.

Furthermore, it is recalled that a laser beam is a particular light beam composed of coherent and concentrated light. The term "laser" is an acronym designating in English language "Light Amplification by Stimulated Emission of Radiation" and meaning "amplification of light by stimulated emission of radiation". In addition, the term “light beam” is intended to mean a beam generally composed of lights visible to the human eye. However and by extension, one can also designate by “light beam”, a beam composed of invisible electromagnetic waves, for example located in the infrared and ultraviolet domains. A laser beam can therefore be a light beam located both in the area visible to the human eye and in the non-visible area.

In addition, a device for correcting the trajectory of projectiles is described in the document. FR 2719659 . This correction device emits a beam for guiding the projectiles directed towards a target. This guide beam is divided into at least five partial beams, a central partial beam effectively directed at the target and at least four partial beams inclined with respect to the central partial beam. Projectiles illuminated by an inclined partial beam therefore do not point towards the target and have their trajectories corrected accordingly.

We also know the documents US 2009/078817 and EP 2642238 which describe a guidance system for a missile or other projectile on a target illuminated by a laser beam.

In particular, the document US 2009/078817 discloses a projectile guidance system to reduce the number of pulses of the guide beam to reduce the total energy sent to the target. This device requires communication between the projectile and the generator of the guide beam in order to synchronize the reception of the reflected guide beam and the emission of this guide beam.

We also know the document US 6,069,656 which describes a method and an image stabilization device for a laser guidance system of a projectile. This method notably allows the possibility of displaying the total scene captured by a camera or even only a part of this scene corresponding to a zoom mode. In addition, this method allows the display of a single point of contact of the guide beam, the distance between a reticle located on the target and this point of contact being used to correct the guide beam.

Finally, we know the documents US 2013/087684 , WO 2016/009440 and US 6023322 which describe a system and / or a method for analyzing the quality criteria of a guide beam of a laser designation system of a target.

According to the document US 2013/087684 , an image capture means allows the analysis of the guide beam through the contact points of this guide beam on the target.

According to the document WO 2016/009440 , a radiation capture means allows the analysis of the guide beam reflected by the target, in particular, the time of arrival of this guide beam reflected by the target on the sensor, its angle of arrival and / or its arrival position on the sensor.

The document US 6023322 makes it possible to determine the ratio between the number of points of contact of this guide beam reflected by the target and the number of pulses of this guide beam emitted making it possible for example to find the best zone of the target to be aimed with the guide beam .

In this context, the present invention aims to allow a reliable and precise aiming of a guide beam on a target. The present invention makes it possible to provide the operator with feedback on the zone actually targeted by means of an image of the environment and of the target. The present invention notably uses a new type of camera allowing the creation of a selective image of the target in the environment.

The subject of the present invention is therefore a method for assisting in the aiming of a target as well as a device for assisting in the aiming of a target making it possible to overcome the limitations mentioned above in order to improve quality and accuracy of aiming the target via a guide beam. The present invention also relates to a method of guiding a projectile by a guide beam using such a sighting aid method as well as a device for guiding a projectile by a guide beam equipped with such a device. sighting aid.

• une première étape de balayage complet d'un environnement à l'aide d'une caméra,
• une deuxième étape d'affichage d'une image complète de l'environnement,
• une troisième étape d'identification et de sélection d'une cible sur l'image complète de l'environnement,
• une quatrième étape de pointage de la cible par un opérateur par l'intermédiaire d'un faisceau de guidage,
• une cinquième étape d'affichage d'une image complète de l'environnement et du point de contact du faisceau de guidage dans l'environnement,
• une sixième étape de pointage par l'opérateur par l'intermédiaire d'un faisceau de guidage de la cible,
• une septième étape de balayage sélectif de la cible et du point de contact du faisceau de guidage dans l'environnement à l'aide de la caméra, et
• une huitième étape d'affichage d'une image sélective de la cible et d'au moins un point de contact du faisceau de guidage dans l'environnement.

According to the invention, a method for assisting in the targeting of a target comprises the following steps:

• a first step of complete scanning of an environment using a camera,
• a second step of displaying a complete image of the environment,
• a third step of identifying and selecting a target on the complete image of the environment,
• a fourth step of aiming the target by an operator via a guide beam,
• a fifth step of displaying a complete image of the environment and of the point of contact of the guide beam in the environment,
• a sixth step of aiming by the operator by means of a target guiding beam,
• a seventh step of selective scanning of the target and the point of contact of the guide beam in the environment using the camera, and
• an eighth step of displaying a selective image of the target and at least one point of contact of the guide beam in the environment.

This method according to the invention is particularly intended for methods of guiding a projectile by a guide beam towards a target. The guide beam is emitted by a generator of a guide beam. The guide beam can be a light beam visible or not visible to the human eye depending on the wavelength (s) making up this light beam. The guide beam is preferably a laser beam. This laser beam is for example emitted by a generator of a laser beam of known type such as a laser designator dedicated to the aiming of a target.

In addition, the guide beam can be a continuous beam or else be formed by a succession of pulses at regular intervals. In the latter case, the guide beam is notably defined by temporal characteristics which are the frequency and the duration of these pulses.

The generator of a guide beam can be portable and used directly by an operator. The generator of a guide beam can also be embedded in a vehicle.

In addition, the generator of a guide beam can be linked to the projectile launching device, the generator of a guide beam and the projectile launching device being for example carried by the same vehicle. We then speak of "autonomous designation" or "autonomous designation" in the English language.

The generator of a guide beam can also be carried by a third party, for example by a ground shooter, and then isolated from the projectile launching device, carried for example by a vehicle. We then speak of "external designation" or "remote designation" in the English language.

This method also uses a camera in order to record the environment and the target as well as a visualization means for displaying in particular the images recorded by the camera. The display means can be integrated into a telescopic sight of a generator of a portable guide beam or else into a helmet for a generator of guide beam on board a vehicle. The display means can also be a remote screen vis-à-vis the generator of a guide beam.

Likewise, the camera can be linked to the generator of a guide beam or isolated from this generator of a guide beam. For example, the generator of a guide beam is carried by an operator located on the ground while the camera is carried by a vehicle, the vehicle possibly being able to also carry the device for launching the projectile.

The camera used by the method according to the invention is preferably a new type of camera known by the English expression "bio-inspired camera" or "event based". These cameras are characterized by a very high radiometric dynamic, for example the ability to see light and dark objects at the same time, and by a very high temporal resolution, of the order of a microsecond. By their principle, these cameras therefore make it possible for each pixel to measure a change in radiometry with high temporal precision. A detection of change in the scene, for example by the presence of a pulse of a guide beam or a moving object, is therefore done naturally. “Radiometry of an object” is understood to mean the measurement of the energy quantity relating to the radiations emitted by this object or else derived properties such as the flux or the intensity of these radiations.

Thus, particular objects for which a change in their respective radiometry is detected can be isolated in the environment. In this way, such a camera does not necessarily record a complete image of the environment as does a traditional camera, but an image of the environment comprising only one or more particular objects, for which a change in their radiometry is detected, and in particular one or more selected targets.

An aiming procedure always begins with a scan of the visible environment in search of targets, then by stopping the scan to focus on a target.

The first step of the method according to the invention therefore consists in a complete scanning of an environment using the camera. A complete image of this environment is therefore recorded. This complete image of this environment is then displayed during the second step on the display means so that a target on this complete image of the environment is identified and selected during the third step.

This identification and selection is made by an operator who is for example the operator in charge of aiming the target with the guide beam. The operator identifies the target on the complete image of the environment and then selects it.

This selection can be made by the operator aiming at the target via the generator of a guide beam, but without emitting a guide beam. The operator then uses the telescopic sight of this generator of a guide beam and when he aims at the target, he actuates a selection means such as a push button or a switch to select the targeted target. The operator generally uses the sighting reticle present in the sighting scope of the generator of a guide beam to aim at the target.

This selection can also be made directly on the display means by moving the sighting reticle on the target, then by actuating the selection means. The reticle can be moved by a mouse or directly on the display means which is then a touch screen, the target selection means also being this mouse or this touch screen.

The target can also be identified by its coordinates, for example according to a satellite location system, the operator then selecting it via the selection means to confirm that the coordinates correspond to the target.

In all cases, the selection of the target can be automatic when the operator aims at a stationary target or when the aiming reticle is kept stationary for a first predetermined duration. This first predetermined duration is for example 3 seconds (3s).

This automatic selection is also possible for a moving target, in particular by using an image processing system, designated for example in English by the expression "moving target indicators", aligning the reticle on the identified moving target.

Then, the operator points the guide beam at the target during the fourth step in order to guide the projectile to the target. The operator generally uses the sight reticle present in a sight telescope of the generator of a guide beam to aim the target or directly on the visualization means by positioning the aim reticle on the target. In addition, the operator must in fact continuously point the guide beam at the target via the beam generator. guidance until the projectile hits the target. In fact, if the operator points the guide beam at another object outside the target, the projectile will then move towards this other object. Likewise, if the operator stops the generator of a guide beam and if no guide beam is emitted, the projectile will not know where to go.

Furthermore, the first step and the second step are preferably repeated as long as the operator has not pointed the guide beam at the target in order to update the complete display of the environment.

In addition, the operator generally does not see the point of contact of the guide beam on the target, the guide beam may be visible or not visible to the human eye. In fact, the operator cannot verify whether the beam actually illuminates the intended target.

However, the guide beam and its reflection on the target are advantageously always visible by the camera. As a result, the contact points of the guide beam in the environment and in particular on the target are always visible and can be recorded by the camera.

It should be noted that other devices making their appearance today make it possible to record contact points of the guide beam in the environment. For example, there is a sensor whose designation in English is “see spot”. However, these devices have a low recording frequency and cannot therefore record the contact points of the guide beam in the environment if they are too close in time to each other and provided that they fall into the time window where these devices record an image.

The method according to the invention then advantageously comprises a fifth step during which the complete image of this environment is displayed on the display means with the point of contact of the guide beam in the environment.

The operator can then visualize the point of contact of the guide beam on the image of the environment and verify that this point of contact is indeed on the target. In this way, if this contact point is not located on the target, the operator can then correct the aim. Indeed, a shift between the sighting reticle and the guide beam itself may exist due to inaccuracies in the system and cause a shift between the sighting direction and the direction of the guide beam and, consequently, a sighting error. .

Then, during the sixth step, the operator again points the target with the guide beam. The operator can during this sixth step possibly correct the aiming as a function of the position of the point of contact of the guide beam on the environment with respect to the target on the image displayed during the previous step. .

The target being identified, the camera used by the method advantageously makes it possible during the seventh step to selectively scan the target and the point of contact of the guide beam in the environment. Indeed, as mentioned above, the camera used by the method according to the invention makes it possible to record only part of the environment for which a change in radiometry is detected. Thus, this camera can specifically record the target selected during the third step and impacted by the guide beam as well as the point of contact of this guide beam. Other environmental objects may also be recorded according to the change in their respective radiometry. However, the number of objects recorded in step 7 and then displayed in step 8 is significantly reduced when it comes to recording and displaying a complete picture of the environment, in steps 1 and 2 respectively .

Finally, during the eighth step, a selective image of the target and of at least one point of contact of the guide beam in the environment is displayed. Here again, the operator can visualize the contact point of the guide beam on the selective image of the environment and check that this contact point is always on the target. Advantageously, this selective image is simplified and mainly displays the target, the point of contact of the guide beam on the environment and possibly other objects whose radiometry changes. This selective display advantageously allows a faster analysis on the part of the operator who immediately sees the position of the contact point of the guide beam on the environment vis-à-vis the target.

The sixth, seventh and eighth stages are then repeated until the impact of the projectile, these stages being carried out continuously.

Thus, for the sixth pointing step, the operator first uses the complete image displayed during the fifth step to possibly correct the aiming of the target and then uses the selective images displayed successively during the eighth step.

The aiming aid method according to the invention advantageously makes it possible to provide the operator in real time and during his aiming operation with feedback on the positions of the target and of the contact points of the guide beam on the environment thanks to the display of the complete image and then selective images of the environment. This display of the selective image thus makes it possible to improve the aiming precision, the operator being able to immediately correct, in real time and continuously, a deviation from the position of the point of contact of the guide beam on the visible environment. vis-à-vis the target.

Furthermore, in order to facilitate the identification of the target on the displayed image, whether it is a complete image of the environment or else a selective image of the target and of at least one point of contact of the guide beam in the environment, the aiming reticle can be displayed on the target. This aiming reticle can thus be displayed during the second, fifth and eighth display steps of the aiming aid method according to the invention.

In addition, the aiming aid method according to the invention may comprise, after the eighth step, additional steps making it possible to quantify the precision of the aiming of the target. Indeed, the image displayed during the second, fifth and eighth step comprising in particular the target and the point of contact of the guide beam in the environment, it is possible by analyzing each successively displayed image to determine a first number of points of the guide beam contacting the target and a second number of contact points of the guide beam not touching the target since the target was selected in the third step.

The aiming aid method according to the invention can thus include a ninth step of calculating the first number of contact points of the guide beam touching the target, and the second number of contact points of the guide beam not touching the target since the target was selected in the third step. In addition, the percentage of contact points of the guide beam actually touching the target among the all of the contact points of the guide beam in the environment can possibly be calculated during this ninth step.

Then, during a tenth display step, information relating to the precision of the contact points of the guide beam touching the target is displayed on the display means.

This information on the precision of the points of contact of the guide beam touching the target can be this first number and this second number or else the percentage of the points of contact of the guide beam actually touching the target among all the points of contact of the beam. guidance in the environment.

Furthermore, during the eighth step, the contact points of the guide beam in the environment can be recorded for a second predetermined duration, then be displayed with the selective image of the target. The operator can thus view the successive positions of the contact points over this second predetermined duration and thus observe a possible drift in the precision of his aim or else an improvement in this aim.

Therefore, during this eighth step, the selective image of the target and the current contact point of the guide beam in the environment can be displayed simultaneously with at least one of the contact points previously displayed.

“Current contact point” of the guide beam is understood to mean the contact point of the guide beam picked up by the camera during the seventh selective scanning step immediately preceding this eighth step. By "point of contact previously displayed »the contact point displayed during the fifth step of displaying a complete image of the environment and the point of contact of the guide beam in the environment as well as any contact point displayed during any previous eighth display steps. The contact points previously displayed are for example partly constituted by the contact points registered during the second predetermined duration.

Likewise, the ninth stage can also take place over the second predetermined duration. In this way, the information of the precision displayed during the tenth step is determined over this second determined duration.

In addition, the aiming aid method according to the invention may include another additional step taking place after the fourth step, that is to say after aiming the guide beam on the target, and parallel to the steps following, namely from the fifth stage to the eighth stage. This additional step allows the identification of the guide beam aimed at the target. Indeed, the contact points of the guide beam in the environment are always visible and recordable by the camera. In fact, it is possible by analyzing these contact points to determine on the one hand if the guide beam is continuous or else constituted by a succession of pulses and on the other hand of the temporal characteristics of this guide beam. Then, the temporal characteristics of the guide beam used to aim at the target are known and constitute the code of the guide beam. It is then advantageously possible to verify that these temporal characteristics of the guide beam visible on the target do indeed correspond to the code of the expected guide beam and to thus determine that the guide beam visible on the target by the camera is indeed the expected guide beam.

The aiming aid method according to the invention can thus include an eleventh step of analysis and identification of the guide beam, the points of contact of the guide beam in the environment being analyzed in order to determine the temporal characteristics. of the guide beam and thus identify the guide beam code visible on the target.

For a guide beam consisting of a succession of pulses, the temporal characteristics of the guide beam are the frequency and the duration of these pulses. However, a continuous guide beam has no pulses and no frequency can be determined. The temporal characteristics of such a continuous beam are in fact the absence of pulses and frequency.

It should be noted that existing devices making it possible to record contact points of the guide beam in the environment, such as a “see spot” device, are unable to analyze these contact points in order to determine the temporal characteristics. of the guide beam.

The points of contact of the guide beam in the environment can be recorded from the pointing of the target by the guide beam during the fourth step or else over a third predetermined duration. This third predetermined duration can be equal to the second predetermined duration.

Such recordings of the contact points of the guide beam in the environment may in particular be useful for an analysis subsequent to the firing of the projectile, for example in the event of a target error, and in particular of fratricidal firing.

Finally, the method for assisting in the targeting of a target according to the invention may comprise, between the fourth step of pointing the target and the fifth step of displaying, an intermediate step of complete scanning of the environment at camera help. This intermediate step therefore consists of a new complete scan of the environment in order to update the display of the target and of the environment before the complete display of this environment during the fifth step. This intermediate step notably makes it possible to take into account a possible displacement of the objects of the environment and in particular of the target.

The method of assisting with the aiming of a target according to the invention advantageously makes it possible, during the fifth and eighth steps, to visualize the spatial behavior of the guide beam in the environment and thus to verify the efficiency of the aiming.

In addition, this method makes it possible, during the ninth and tenth steps, to quantify this spatial behavior of the guide beam by providing the precision information.

In addition, this method makes it possible, during the eleventh step, to quantify the temporal behavior of the guide beam and to identify the code of the guide beam in order to ensure that this guide beam is indeed that expected.

• une étape d'illumination d'une cible par un faisceau de guidage,
• une étape d'accrochage du projectile sur la cible,
• une étape de lancement d'un projectile, et
• une étape de guidage du projectile vers la cible.

The present invention also relates to a method for guiding a projectile by a guide beam comprising:

• a step of illuminating a target with a guide beam,
• a step for attaching the projectile to the target,
• a stage of launching a projectile, and
• a step of guiding the projectile towards the target.

The guide beam is preferably a laser beam. The aiming assistance method previously described is then applied to the illumination step in order to improve the precision of this illumination of the target and, consequently, to improve the precision of the launching of a projectile on the target.

The projectile attachment step on the target can then be carried out as a function of the information of the precision of the contact points of the guide beam touching the target and / or of the temporal characteristics of the guide beam impacting the target. This hooking step can be carried out manually by the operator.

This realization can also be done automatically if the information on the precision of the contact points of the guide beam touching the target is greater than or equal to a predetermined threshold and / or if the temporal characteristics of the guide beam impacting the target correspond to the code of the expected guide beam.

In addition, the projectile launching step can be canceled as a function of this information on the precision of the contact points of the guide beam touching the target. This cancellation can be done manually by the operator. This cancellation can also be carried out if the operator finds on the display of the selective image during the eighth step an unforeseen event, for example a vehicle approaching the target, this vehicle not having to be impacted by the projectile.

This cancellation can also be done automatically if the information on the accuracy of the contact points of the guide beam touching the target is less than the predetermined threshold and / or if the temporal characteristics of the beam guides impacting on the target do not correspond to the expected guide beam code.

Thus, if the precision of the points of contact with respect to the selected target is sufficient, the attachment and / or the firing of the projectile is carried out. Otherwise, the probability that the projectile will hit the target is too low and the projectile is not hooked and / or fired.

Furthermore, the projectile launching step can be carried out before the projectile attachment step on the target.

The present invention also relates to a device for assisting in the targeting of a target comprising a camera, a display means, a calculator and a selection means.

The camera makes it possible to record information specifically on particular objects in the recorded environment, the target being a particular object in the environment. The particular objects are isolated by this camera according to a change in their respective radiometry, for example following a movement of the particular objects.

Furthermore, the computer of this device for assisting in the targeting of a target can be configured in particular in order to analyze each image successively displayed on the display means and to determine a first number of contact points of the guide beam touching the target and a second number of contact points of the guide beam not touching the target. This computer also makes it possible to determine the percentage of these points of contact of the guide beam actually touching the target among all the points of contact of the guide beam in the environment.

The computer can also be configured to analyze the environment seen by the camera and in particular the contact points of the guide beam in this environment in order to determine the temporal characteristics of the guide beam and, consequently, to identify the guide beam code.

The device for assisting with the aiming of a target can thus implement the method for assisting with the aiming of a target previously described in order to improve the accuracy of aiming of the target.

Finally, the present invention also relates to a system for guiding a projectile by a guide beam comprising a generator of a guide beam, a sighting aid device as previously described and a projectile provided with a receiving device.

The sighting aid is configured to improve the accuracy of target illumination so that the accuracy of projectile fire on the target is improved. The generator of a guide beam is preferably a generator of a laser beam.

This system for guiding a projectile by a guide beam can thus implement the method for guiding a projectile by a guide beam previously described.

• la figure 1, un système de guidage d'un projectile par un faisceau de guidage selon l'invention,
• la figure 2, un schéma synoptique d'un procédé d'aide à la visée d'une cible,
• les figures 3 et 4, une image complète de l'environnement affichée sur le moyen de visualisation, et
• les figures 5 à 7, une image sélective de l'environnement affichée sur le moyen de visualisation.

The invention and its advantages will appear in more detail in the context of the description which follows with examples of embodiment given by way of illustration with reference to the appended figures which represent:

• the figure 1 , a system for guiding a projectile by a guide beam according to the invention,
• the figure 2 , a block diagram of a method for assisting in the targeting of a target,
• the figures 3 and 4 , a complete image of the environment displayed on the display means, and
• the Figures 5 to 7 , a selective image of the environment displayed on the display means.

The elements present in several separate figures are assigned a single reference.

The figure 1 represents a system 20 for guiding a projectile 10 by a guide beam comprising a generator 6 of a guide beam 9, a projectile 10 provided with a receiving device 11 and a device 1 for aiming assistance. This system 20 for guiding a projectile 10 by a guide beam ensures the guiding of the projectile 10, a missile for example, towards a target 5. The generator 6 of a guide beam 9 can be used by an operator to aim a target 5 with the guide beam 9, the operator being located on the ground and fixed. The generator 6 of a guide beam 9 then generally comprises a telescopic sight 61 making it possible to achieve the aim of the target 5. The generator 6 of a guide beam 9 can also be embarked in a vehicle such as an aircraft and used then both when the vehicle is moving or when it is stationary. This guide beam 9 is for example a laser beam consisting of successive pulses.

The target 5 is first of all illuminated by the guide beam 9 emitted by the generator 6 of a guide beam 9 and reflections of this guide beam 9 are then dispersed in a multitude of directions by reflection on the target 5 The guide beam 9 may be visible or not visible to the human eye depending on the wavelength (s) making up this guide beam 9.

In parallel with or following this illumination of the target 5, the projectile 10 is launched in the direction of the target 5. The projectile 10 comprises a receiving device 11 which receives, when it approaches the target 5, part of the guide beam 9 reflected by the target 5 and then determines the source of this part of the guide beam 9 reflected. The projectile 10 is finally guided and directed towards this source, namely the target 5, as long as the guide beam 9 points at the target 5 and illuminates it.

The device 1 for aiming at a target 5 comprises a camera 2, a display means 3, a computer 4 and a selection means 7. The display means 3 is a screen. The device 1 for aiming at a target 5 is configured in order to improve the accuracy of aiming at target 5 by implementing a method for assisting at aiming at a target, a block diagram of which is depicted on the figure 2 and which includes the following steps.

During a first scanning step 101, a complete scanning of an environment is carried out using the camera 2.

During a second display step 102, a complete image of this environment corresponding to this complete scanning of the environment is displayed on the display means 3. This complete image is represented on the figure 3 .

During a third step of identifying and selecting a target 103, a target 5 is identified and then selected from this complete image of the environment. This identification is made by an operator who is in charge of aiming the target with the guide beam 9.

Then, the operator selects target 5 on the complete image of the environment. This selection is made by means of a selection means 7 such as a push button while the operator is targeting the target 5. This selection is made by the operator when he is targeting the target 5 by means of the generator 6 of a guide beam, but without emitting a guide beam. The operator then uses for example the aiming scope 61 of this generator 6 of a guide beam to aim at the target 5, then he actuates the selection means 7 to select the targeted target 5.

This selection of the target 5 can also be made automatically when the operator targets a stationary target 5 or for a first predetermined duration.

During a fourth step 104, the operator points the guide beam 9 at the target 5 in order to guide the projectile 10 to this target 5. The operator generally uses the aiming reticle present in the telescopic sight 61 of the generator 6 of a guide beam for targeting the target 5.

The first step 101 and the second step 102 are repeated before the completion of this fourth step 104 in order to update the complete display of the environment.

During a fifth display step 105, the complete image of this environment is displayed on the display means 3 with the contact point 91 of the guide beam 9 in the environment. In fact, the guide beam 9 and its reflection on the target 5 are advantageously always visible by the camera 2. In addition, an aiming reticle 8 can also be displayed on the display means 3 thus indicating to the operator the point of the target environment. This complete image comprising the contact point 91 of the guide beam 9 and the sighting reticle 8 is shown on the figure 4 .

This fifth display step 105 thus allows the operator to view and verify on the one hand that the aiming reticle 8 points well at the target 5 and on the other hand that the contact point 91 of the guide beam 9 points also the target 5. In fact, the operator must constantly point the guide beam 9 at the target 5 until the projectile 10 impacts the target 5.

In addition, an intermediate step 115 of complete scanning of the environment can be carried out between the fourth step 104 of pointing the target 5 and the fifth step 105 of display. In this way, by carrying out a new complete scan of the environment using the camera 2, a new complete image of the environment with the point of contact 91 of the guide beam 9 can be displayed during the fifth step. 105 in order to update this display of target 5 and the environment.

Then, during a sixth pointing step 106, the operator again points the target 5 with the guide beam 9. This sixth pointing step 106 advantageously allows the operator to correct the aim if the contact point 91 is not located on target 5 on the complete image displayed during the fifth display step 105.

During a seventh scanning step 107, a selective scanning of the target 5 and of the contact point 91 of the guide beam 9 in the environment is carried out by the camera 2. The camera 2 is a camera making it possible in fact to '' specifically record information on particular objects in the environment according to a change in their radiometry following, for example, their movement. For example, the camera 2 makes it possible to record specifically and only the information on particular objects in the environment which are in motion, as well as the contact points 91 of the guide beam 9.

Finally, during an eighth display step 108, this selective image of the target 5 and of at least one contact point 91 of the guide beam 9 in the environment is displayed. Here again, the operator can view the contact point 91 of the guide beam 9 on the selective image of the environment and check that this contact point 91 is always well on the target 5. Advantageously, this selective image is simplified and mainly displays the target 5 which is for example in motion and the point of contact 91 of the guide beam 9 on the environment. This selective image advantageously allows a quicker analysis on the part of the operator who immediately sees the position of the contact point 91 with respect to the target 5. As during the fifth display step 105, the reticle of target 8 can be displayed on the display means 3 in order to indicate to the operator the point of the environment which is targeted. This selective image comprising the contact point 91 of the guide beam 9 and the sighting reticle 8 is shown on the figure 5 .

The sixth, seventh and eighth stages are then repeated until the impact of the projectile 10, these stages being carried out continuously.

The aiming aid device 1 thus advantageously makes it possible to provide the operator in real time and during his aiming operation with a return to the positions of the target 5 and of the contact point 91 of the guide beam 9 on the environment thanks to the images displayed on the viewing means 3 after having identified and selected the target 5. The operator can then immediately correct a difference between the position of the contact point 91 with respect to the target 5 and thus improve the aim accuracy.

In addition, the aiming aid device 1 also makes it possible to quantify the precision of the aiming. Indeed, the computer 4 is configured in order to analyze each image successively displayed on the display means 3 and to determine, during a ninth step 109, a first number of contact points 91 of the guide beam 9 touching the target 5 and a second number of contact points 91 of the guide beam not touching the target 5. This computer 4 also makes it possible to calculate the percentage of these contact points 91 actually touching the target 5 among all the contact points 91 of the guide beam 9 in the environment. Then, during a tenth step 110, information 92 of the precision of the contact points 91 touching the target 5 formed by this percentage of contact points 91 actually touching the chosen target can be displayed on the display means 3.

The ninth step 109 and the tenth step 110 preferably take place simultaneously with the sixth, seventh and eighth steps as shown in the block diagram of the figure 2 , and repeat until the impact of projectile 10.

Furthermore, during the eighth step 108, the contact points 91 of the guide beam 9 in the environment can be recorded for a second predetermined duration, then be displayed with the selective image of the target 5.

Therefore, during the eighth display step 108, the selective image of the target 5 and the current contact point 91 of the guide beam 9 picked up during the seventh scanning step 107 can be displayed simultaneously with at least one of the contact points 91 previously displayed during the fifth display step 105 and during previous eighth display steps 108, if any.

Likewise, the ninth step 109 can also take place over the second predetermined duration. In this way, the information 92 of the precision displayed during the tenth step 110 is determined over this second determined duration.

This information 92 is displayed on the display means 3 with the contact points 91 recorded during the second predetermined duration as shown in the Figures 6 and 7 . The operator can thus visualize the positions of the contact points 91 over this second predetermined duration and thus visualize the precision of the contact points 91 with respect to the target 5.

This information 92 can also be used by the guidance system 20 of a projectile 10 in order to confirm or cancel the attachment of the projectile 10 to the target 5 and the launching of the projectile 10 in the direction of the target 5. In Indeed, if the aiming accuracy is considered too low by the operator, he can cancel the launching of the projectile 10 or else stop it momentarily until there is sufficient aiming accuracy. This cancellation can also be done automatically if the information 92 of the precision of the contact points 91 of the guide beam 9 touching the target 5 is less than a predetermined threshold.

Finally, the aiming aid device 1 makes it possible to identify the code of the guide beam 9 targeting the target 5. In fact, the computer 4 is configured in order to analyze the environment seen by the camera 2 and in particular the contact points 91 of the guide beam 9 in the environment. The computer 4 can thus determine, during an eleventh step 111, the temporal characteristics of the guide beam 9 and identify the code of this guide beam 9. This eleventh step 111 takes place after the fourth step 104 and in parallel with the steps following.

Naturally, the present invention is subject to numerous variations as to its implementation. Although several embodiments have been described, it is understood that it is not conceivable to identify exhaustively all the possible modes. It is of course conceivable to replace a means described by an equivalent means without departing from the scope of the present invention.

Claims (16)

1. Aiming-assistance method for a target (5), characterised in that the said method comprises the following steps,

   - a first step (101) of complete scanning of an environment by means of a camera (2),

   - a second step (102) of displaying a complete image of the said environment,

   - a third step (103) of identifying and selecting a target (5) on the said complete image of the said environment,

   - a fourth step (104) of aiming at the said target (5) by an operator by means of a guide beam (9),

   - a fifth step (105) of displaying a complete image of the said environment and the point of contact (91) of the said guide beam (9) in the said environment,

   - a sixth step (106) of aiming at the said target (5) by the said operator by means of the said guide beam (9),

   - a seventh step (107) of selective scanning of the said target (5) and point of contact (91) of the said guide beam (9) in the said environment by means of the said camera (2),

   - an eighth step (108) of displaying a selective image of the said target (5), the said current point of contact (91) of the said guide beam (9) in the said environment and at least one of the said previously displayed points of contact (91),

   - a ninth step (109) of calculating a first number of the said points of contact (91) of the said guide beam (9) touching the said target (5) and a second number of the said points of contact (91) of the said guide beam (9) not touching the said target (5), and

   - a tenth step (110) of displaying information of the accuracy of the said points of contact (91) of the said guide beam (9) touching the said target (5).
2. Aiming-assistance method for a target (5) according to claim 1, characterised in that during the said eighth step (108) the said points of contact (91) of the said guide beam (9) in the said environment are recorded for a predetermined time, and are then displayed with the said selective image of the said target (5).
3. Aiming-assistance method for a target (5) according to either of claims 1 and 2, characterised in that the said information of the accuracy of the said points of contact (91) of the said guide beam (9) touching the said target (5) is formed by the said first number and the said second number or by the percentage of the said points of contact (91) of the said guide beam (9) actually touching the said target (5) of the total number of the said points of contact (91) of the said guide beam (9) in the said environment.
4. Aiming-assistance method for a target (5) according to any one of claims 1 to 3, characterised in that the said ninth step (109) takes place for a predetermined time.
5. Aiming-assistance method for a target (5) according to any one of claims 1 to 4, characterised in that if a guide beam (9) is defined by a code consisting of time characteristics, the said method comprises, after the said fourth step (104) of aiming at the said target (5) and in parallel to the said following steps, an eleventh step (111) of analysing and identifying the said guide beam (9), the said points of contact (91) of the said guide beam (9) in the said environment being analysed so as to determine the said time characteristics of the said guide beam (9) and to identify the said code of the said guide beam (9).
6. Aiming-assistance method for a target (5) according to claim 5, characterised in that when the said guide beam (9) consists of a succession of pulses, the said time characteristics of the said guide beam (9) are a frequency and a duration of the said pulses.
7. Aiming-assistance method for a target (5) according to any one of claims 1 to 6, characterised in that the said method comprises, between the said fourth step (104) of aiming at the said target (5) and the said display step (105), an intermediate step (115) of complete scanning of the said environment by means of the said camera (2) so as to update the display of the said target (5) and the said environment.
8. Aiming-assistance method for a target (5) according to any one of claims 1 to 7, characterised in that cross hairs (8) are displayed on the said target (5) during the said second, fifth and eighth display steps (102, 105, 108) so as to facilitate the identification of the said target (5).
9. Aiming-assistance method for a target (5) according to any one of claims 1 to 8, characterised in that during the said seventh scanning step (107), the said selective scanning of the said target (5) and of the said point of contact (91) of the said guide beam (9) is carried out by recording each object of the said environment for which a change of the radiometry is detected as well as the point of contact (91).
10. Aiming-assistance method for a target (5) according to any one of claims claim 1 to 8, characterised in that during the said seventh scanning step (107), the said selective scanning of the said target (5) and of the said point of contact (91) of the said guide beam (91) is carried out by recording information on particular objects of the environment that are moving, as well as the said point of contact (91).
11. Method for guiding a projectile (10) by a guide beam, comprising

    - a step of illuminating a target (5) by a guide beam (9),

    - a step of targeting the said projectile (10) on the said target (5),

    - a step of launching the said projectile (10), and

    - a step of guiding the said projectile (10) to the said target (5),
    characterised in that the said aiming-assistance method according to any one of claims 1 to 10 is applied during the said illumination step so as to improve the accuracy of the said illumination of the said target (5).
12. Method of guiding a projectile (10) by a guide beam according to claim 11, characterised in that the said step of targeting the said projectile (10) on the said target (5) and/or the said step of launching the said projectile (10) are cancelled depending on information of the accuracy of the said points of contact (91) of the said guide beam (9) touching the said target (5) and/or time characteristics of the said guide beam (9).
13. Aiming-assistance device for a target (5), comprising a camera (2), a visualisation means (3), a computer (4) and a selection means (7), characterised in that the said aiming-assistance device (1) for a target (5) is configured for the implementation of the said method according to any one of claims 1 to 10 and the said camera (2) is a camera enabling information to be specifically recorded concerning the particular objects of the recorded environment, the said target (5) being a particular object of the said environment, the said computer (4) being configured so as to analyse each selective image successively displayed on the said visualisation means (3) and to determine a first number of points of contact (91) of the said guide beam (9) touching the said target (5) and a second number of points of contact (91) of the said guide beam (9) not touching the said target (5), and information is then determined concerning the accuracy of the said points of contact (91) of the said guide beam (9) touching the said target (5).
14. Aiming-assistance device for a target (5) according to claim 13, characterised in that the said computer (4) is configured so as to analyse the said environment seen by the said camera (4) and in particular the said points of contact (91) of the said guide beam (9) in the said environment so as to determine time characteristics of the said guide beam (9) and to identify the said guide beam (9) by means of the said time characteristics.
15. System (20) for guiding a projectile (10) by a guide beam (9), comprising a guide beam generator (6) and a projectile (10) provided with a receiving device (11), characterised in that the said system (20) for guiding a projectile (10) comprises an aiming-assistance device (1) according to either of claims 13 and 14.
16. System (20) for guiding a projectile (10) by a guide beam according to claim 15, characterised in that the said system (20) for guiding a projectile (10) by a guide beam implements the said method for guiding a projectile (10) by a guide beam according to either of claims 11 and 12.

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