Method and system for detecting a flying device in an airspace

Abstract

A method for detecting a flying apparatus (3) in an airspace (EA) by a detection system (S), the detection system (S) comprising at least one ground station (1) and at least one tracking drone (2), the method comprising steps of detecting a position of at least one flying apparatus (3) in the airspace (EA), hereinafter "target position" (PosC), transmitting the target position (PosC) to the tracking drone (2), automatically moving the tracking drone (2) to the target position (PosC), detecting, by the tracking drone (2), a position of at least one flying apparatus (3) in a vicinity of the tracking drone (2), hereinafter "local position" (PosL), transmitting the local position (PosL) to the ground station (1), and determining, by the ground station (1), a refined position from the local position (PosL). Abstract figure: Figure 8

Description

Title of the invention: Method and system for detecting a flying device in an airspace Technical field

[0001] The present invention relates to the field of air defense, more precisely a system for detecting and intercepting a flying device.

[0002] In the context of defending a site to be protected, it is necessary to identify potential long-range threats, for example, flying devices (drones, etc.) which are generally used to carry out reconnaissance missions or transport explosive charges. Detecting potential threats at long range is essential to guarantee the protection of the infrastructure and people at the site to be protected.

[0003] It is known in the prior art to use a ground-based detection system comprising a radar directed towards the sky to monitor the airspace around the site to be protected. Such a detection system makes it possible to detect flying devices in the airspace at long range, but does not offer sufficient precision to identify and intercept the detected flying device. For example, such a detection system does not make it possible to identify at long range whether the detected flying device is a friend or an enemy.

[0004] Furthermore, to intercept a flying device at long range, it is known to use a long-range jammer to disorient the flying device. Unfortunately, this type of jammer disrupts all electronic devices in a wide area and can cause collateral damage to friendly or civilian equipment. One solution to eliminate this drawback would be to use a laser or the like to intercept the flying device. However, such a solution cannot be implemented at long range since the detected position does not have sufficient precision.

[0005] The invention thus aims to eliminate at least some of these drawbacks, by proposing a new system for detecting and intercepting a flying device allowing more precise detection. PRESENTATION OF THE INVENTION

[0006] The invention relates to a method for detecting a flying device in an airspace by a detection system, the detection system comprising at least one ground station and at least one tracking drone, the method comprising steps consisting of: • Detect, by the ground station, a position of at least one aircraft flying in the airspace, hereinafter “target position”, • Transmit, via the ground station, the target position to the tracking drone, • Automatically move the tracking drone to the target position, • Detect, by the tracking drone, a position of at least one flying device in a vicinity of the tracking drone, hereinafter “local position”, • Transmit, by the tracking drone, the local position to the ground station, and • Determine, by the ground station, a refined position from the position local.

[0007] Thanks to the invention, a local position is obtained thanks to the tracking drone which makes it possible to increase precision. The use of a tracking drone makes it possible to ensure precise tracking of a flying device in order to be able to locate it, identify it or intercept it if necessary. Any aerial threat is thus optimally contained.

[0008] Preferably, the method comprises a step of controlling an interception device so that it targets the aircraft flying at the refined position. The use of a highly precise refined position advantageously makes it possible to implement a targeted interception without risk of collateral damage.

[0009] According to one aspect, the refined position is displayed on a display screen of the ground station. This allows an operator to accurately view the trajectory of the flying apparatus and to know, at any time, its precise position.

[0010] According to one aspect, a position of the tracking drone is continuously determined by the tracking drone and sent to the ground station. This allows the operator to quickly view on a display device the aerial situation to ensure that the flying apparatus is under control.

[0011] According to one aspect, the refined position corresponds to the local position. Such a refined position is used when the tracking drone performs high-quality detection, in particular, by means of a lidar.

[0012] According to one aspect, the refined position is determined from the target position and the local position, preferably from the target position, the local position and the position of the tracking drone. The use of several position measurements advantageously makes it possible to reduce inaccuracies.

[0013] According to one aspect, the target position is detected and transmitted to the tracking drone continuously. This allows the tracking drone to dynamically adapt its trajectory when homing the flying apparatus.

[0014] According to one aspect, the method comprises a step consisting of comparing a separation distance, determined between the local position and the target position, with a neighborhood threshold, the tracking drone transmitting the local position only if the separation distance is less than the neighborhood threshold.

[0015] This allows the tracking drone to discard any intruder that does not match the flying device detected by the ground station when the flying device is homing.

[0016] According to one aspect, the method comprises a tracking step of automatically moving the tracking drone as a function of the local position and a detection vector defined between the tracking drone and the flying apparatus, preferably without taking into account the target position.

[0017] The use of a detection vector, preferably obtained by a lidar, makes it possible to detect the speed and / or acceleration of the flying device, which makes it possible to estimate its trajectory and, preferably, to facilitate its homing even when the latter is in motion.

[0018] The invention also relates to a system for detecting an aircraft flying in an airspace, the detection system comprising at least one ground station and at least one tracking drone, • the ground station being configured to: • detect a position of at least one aircraft flying in the airspace, hereinafter “target position”, • transmit the target position to the tracking drone, • the tracking drone being configured to move automatically to the target position, • the tracking drone being configured to: • detect a position of at least one device flying in the vicinity of the tracking drone, hereinafter “local position”, • transmit the local position to the ground station, • the ground station being configured to: • determine a refined position from the local position.

[0019] According to one aspect, the ground station comprises a monitoring device for detecting the target position, in particular, a long-range radar.

[0020] According to one aspect, the tracking drone comprises a detection device, preferably a lidar.

[0021] A lidar allows reliable detection both at night and on a black target. Its three-dimensional operation allows for the determination of a precise distance but also speeds and accelerations, which makes it easier for the drone to track the flying device.

[0022] In one aspect, the lidar has a horizontal aperture angle greater than 70 degrees and a vertical aperture angle greater than 70 degrees.

[0023] According to one aspect, the tracking drone comprises a navigation module configured to: • Compare a separation distance, determined between the local position and the target position, to a neighborhood threshold, • Transmit local position only if the spread distance is less than the neighborhood threshold.

[0024] According to one aspect, the tracking drone comprises an image capture device configured to continuously transmit the captured images to the ground station. This allows the flying apparatus to be visually identified.

[0025] According to one aspect, the system comprises an interception device, in order to intercept the flying apparatus at the refined position. Preferably, the interception device is mounted on the tracking drone. This thus allows for reactive interception locally.

[0026] Preferably, the interception device is a short-range jammer.

[0027] The invention also relates to an aerial drone comprising a short-range jammer. According to one aspect, the frequency(ies) jammed by the short-range jammer can be configured by an operator. According to one aspect, the jamming power can be configured by an operator. PRESENTATION OF THE FIGURES

[0028] The invention will be better understood on reading the description which follows, given by way of example, and referring to the following figures, given by way of non-limiting examples, in which identical references are given to similar objects.

[0029] [Fig.l] is a schematic representation of a detection system according to the invention.

[0030] [Fig.2] is a schematic representation of a detection system according to the invention seen from above, presenting a plurality of tracking drones.

[0031] [Fig.3] is a schematic representation of a tracking drone.

[0032] [Fig.4] is a schematic representation of the entry of a flying apparatus into the airspace of the site to be protected.

[0033] [Fig.5] is a schematic representation of a step of homing the flying device by the tracking drone.

[0034] [Fig.6] is a schematic representation of a detection step during the homing of the flying apparatus.

[0035] [Fig.7] is a schematic representation of a tracking drone detecting a bird upon homing of the flying device.

[0036] [Fig.8] is a schematic representation of a tracking drone detecting the flying device and transmitting the position of the flying device to the ground station.

[0037] [Fig.9] is a schematic representation of the step of tracking the flying device by the tracking drone.

[0038] [Fig. 10] is a schematic representation of a tracking drone receiving an intercept command and activating a short-range jammer to intercept the aircraft.

[0039] It should be noted that the figures set out the invention in detail to implement the invention, said figures can of course be used to better define the invention where appropriate. DETAILED DESCRIPTION OF THE INVENTION

[0040] The invention will be presented in a military context to ensure the defense of a site to be protected SAP as illustrated in Figures 1 and 2. The site to be protected SAP can take various forms, for example, a military camp, an official building, a leisure area, etc. It is important to ensure the safety of property and people in said site to be protected SAP.

[0041] In this example, the site to be protected SAP is equipped with a detection system S which is configured to detect a flying device in an airspace EA defined around the site to be protected SAP. The detection system S is also configured to intercept the flying device as will be presented later.

[0042] With reference to [Fig.2], the detection system S comprises a ground station 1 and several tracking drones 2. In this example, for the sake of clarity and conciseness, only a single tracking drone 2 will be presented.

[0043] With reference to [Fig.l], a ground station 1 according to one embodiment of the invention is schematically represented.

[0044] The ground station 1 comprises a command center comprising at least one computer 10, in particular a server or a computer, equipped with a display device on which at least one operator can observe potential threats.

[0045] The ground station 1 comprises a monitoring device 11 configured to detect a position of at least one intruder, for example a flying machine, in the airspace EA, hereinafter referred to as "target position PosC". Preferably, the monitoring device 11 is in the form of a long-range radar making it possible to determine the target position PosC up to 2000 meters. It goes without saying that the monitoring device 11 could be in another form, for example, a combination of goniometer systems for determining the position of the target by triangulation, or any other ground sensor making it possible to determine the position of the target. The target position PosC is determined at long range and is transmitted to the computer 10 in order to reactively warn an operator that an intruder is present.

[0046] Still with reference to [Fig.l], the ground station 1 comprises a video acquisition device 12, connected to the computer 10, to enable the operator to view the intruder and enable its classification, i.e. to determine whether the intruder is, for example, a flying machine or an animal. In practice, the classification at Long range is simple when the intruder is large. In this example, the video acquisition device 12 is a video acquisition camera, in particular, an infrared camera. It goes without saying that a camera capturing in the visible spectrum could also be used. In addition, it is possible to implement a live image processing method on the acquired video stream, in order to determine the position of the target and further information useful to the operator in addition to the surveillance device 11.

[0047] Still with reference to [Fig.l], the ground station 1 also comprises a ground interception device 13 for intercepting the intruder when it is considered a threat. The ground interception device 13 is connected to the computer 10 so that it can be controlled reactively. In this example, the ground interception device 13 may comprise a high-power laser, a long-range jammer or a projectile launcher.

[0048] In this example, the ground station 1 further comprises a communication device 14 for communicating with the tracking drone 2, for example, via a preferably encrypted radio communication link.

[0049] Preferably, the communication device 14 implements encrypted communications in order to ensure that the data is not compromised.

[0050] A tracking drone 2 is shown schematically in [Fig. 3]. The tracking drone 2 comprises a chassis 20 on which are mounted one or more propulsion members 29, for example, electric motors equipped with propellers. It goes without saying that the tracking drone 2 could comprise any kind of propulsion members 29.

[0051] In this embodiment, still with reference to [Fig. 3], the tracking drone 2 comprises a navigation module 21, a detection device 22, an interception device 23, an image capture device, not shown, and a communication module, not shown, for communicating with the ground station 1. The tracking drone 2 further comprises an electric battery, for powering the various equipment of the tracking drone (the propulsion members 29, the navigation module 21, the detection device 22, the interception device 23, the image capture device, the communication module, etc.).

[0052] Preferably, communications between the ground station 1 and the tracking drone 2 are made by 2.4 GHz radio waves.

[0053] The tracking drone 2 comprises a navigation module 21 configured to control the propulsion members 29 in order to direct the tracking drone 2. In this example, the navigation module 21 is in the form of an electronic card. The navigation module 21 is further configured to determine in real time the position of the tracking drone 2, hereinafter referred to as “position of the drone PosD”. By way of example, the navigation module 21 comprises an inertial unit.

[0054] The navigation module 21 is configured to automatically direct the tracking drone 2 to a given position, in particular, to a target position PosC corresponding to that of an intruder or to the storage position of the tracking drone 2. This advantageously makes it possible to provide an immediate response as soon as an intruder is detected by the ground station 1.

[0055] With reference to [Fig. 3], the tracking drone 2 comprises a detection device 22, preferably a lidar. A lidar advantageously makes it possible to detect an intruder at several tens of meters and with very high angular detection precision. In addition, a lidar allows dense scanning of its field of vision and has a reduced mass in comparison with other types of detection devices 22, such as radars. Preferably, the lidar has a horizontal opening angle greater than 70 degrees. Preferably, the lidar has a vertical opening angle greater than 70 degrees. In this example, the lidar has a horizontal opening angle of approximately 70 degrees and a vertical opening angle of approximately 77 degrees.

[0056] Preferably, the lidar is configured to determine a reflectivity index of the intruder in order to facilitate its identification. The use of a lidar allows in particular a three-dimensional vision of the detection field, offering greater precision and measurements of distance, speeds and accelerations along three axes, hereinafter "detection vector Vd". In other words, the lidar makes it possible to determine and estimate the trajectory of the intruder in order to be able to follow it optimally as will be presented later. Preferably, the lidar is mounted in a stabilizing nacelle, so as to maintain high precision of use.

[0057] With reference to Figures 7 and 8, the detection device 22 is configured to detect a position of at least one intruder, hereinafter referred to as “local position PosL”, for example a flying device or a bird, in a vicinity of the tracking drone 2. Preferably, the local position PosL is determined from the position of the tracking drone PosD and the detection vector Vd measured by the detection device 22, in particular, by the lidar. Thanks to the detection vector Vd, in particular its length, the tracking drone 2 can adapt its course to follow the intruder reactively while maintaining a predetermined safety distance. Thus, the tracking drone 2 can supplement or replace the ground station 1 to determine the position of the intruder.

[0058] The navigation module 21 is configured to determine a separation distance EC between the local position PosL and the target position PosC, and to compare it to a neighborhood threshold Sv. This advantageously makes it possible to automatically determine whether the intruder detected by the detection device 22 of the tracking drone 2 corresponds to the intruder detected by the monitoring device 11 of the ground station 1. In the event of a match, the tracking drone 2 starts tracking the intruder, otherwise it continues its movement towards the target position PosC, in particular, avoiding the intruder it previously detected.

[0059] With reference to [Fig. 3], the tracking drone 2 comprises an image capture device, in particular a video camera, configured to continuously transmit the captured images to the ground station 1, in particular, to the computer 10 equipped with its display device. This camera on board the tracking drone 2 advantageously makes it possible to obtain images with high resolution of the intruder due to the proximity of the tracking drone 2 to the intruder. This advantageously allows an operator in the ground station 1 to identify the flying device, to determine in particular its model and whether the latter is an enemy. In addition, image processing algorithms can advantageously be used on the captured images received by the ground station 1 in order to deduce additional data useful to the operator.

[0060] With reference to [Fig. 3], the tracking drone 2 comprises an interception device 23 which is mounted on the chassis 20, in order to intercept the flying apparatus. In other words, the interception device 23 is on board. Preferably, the interception device 23 is a laser, a short-range jammer or a kinetic effector such as a net or a projectile. This allows the tracking drone 2, advantageously, to intercept the flying apparatus without collateral damage locally as will be presented later.

[0061] The interception device 23 is configured to receive an interception order transmitted by the ground station 1, and to intercept the flying device only if the interception order OI is received. When the intruder is identified as an enemy, the operator can thus decide to send the interception order to the ground interception device 13 of the ground station 1 or to the interception device 23 of the tracking drone 2.

[0062] With reference to Figures 4 to 10, an example of implementation of a detection method according to the invention is shown.

[0063] In this example of implementation, with reference to [Fig.4], the tracking drone 2 is in the storage position on the ground and ready to intervene.

[0064] With reference to [Fig. 4], the method comprises a step consisting of detecting El, by the ground station 1, a position of an intruder in the airspace EA, hereinafter “target position PosC”. This detection is carried out at long range by the monitoring device 11 of the ground station 1. In this example, the intruder is a flying device 3 which is visually identified by the video acquisition device 12. In this example, this detection step does not make it possible to determine whether the flying device 3 is a friend or an enemy.

[0065] Still with reference to [Fig.4], the method comprises a step consisting of transmitting E2, by the ground station 1, the target position PosC to the tracking drone 2 via their communication modules. Preferably, the target position PosC is detected and transmitted to the tracking drone 2 continuously.

[0066] With reference to Figures 5 and 6, the method comprises a step consisting of automatically moving E3 the tracking drone 2 to the target position PosC. In other words, the tracking drone 2 makes it possible to join the flying device 3. Preferably, during the joining, the detection device 22 of the tracking drone 2 remains activated and continuously detects any intruder entering a detection zone 5 determined by the detection device 22 (lidar) as illustrated in [Fig.8].

[0067] During the homing, the method comprises a step consisting of detecting E4, by the tracking drone 2, the local position PosL of any intruder in the detection zone 5 of the tracking drone 2. In this example, the local position PosL is determined from the position of the tracking drone PosD (provided by the navigation module 21) and the detection vector Vd measured by the lidar (detection device 22). In this example, the detection vector Vd comprises the speeds and / or accelerations of the intruder along the different axes.

[0068] Preferably, during the homing, the method comprises a step E5 consisting of comparing the separation distance EC, determined between the local position PosL and the target position PosC, with the neighborhood threshold Sv so as to determine whether the detected intruder corresponds to the flying device 3. By way of example, with reference to [Fig.7], the intruder is a bird which is ignored by the tracking drone 2.

[0069] With reference to [Fig.8], the intruder corresponds to the flying device 3 and the local position PosL corresponds to that of the flying device 3.

[0070] The method comprises a step consisting of transmitting E6, by the tracking drone 2, the local position PosL to the ground station 1 and determining E7, by the ground station 1, a refined position PosA from the target position PosC and the local position PosL, as represented in [Fig.8].

[0071] Advantageously, the ground station 1 makes it possible to determine a highly accurate refined position PosA by merging the target position PosC and the local position PosL. Preferably, the refined position PosA is determined from the target position PosC, the local position PosL and the position of the drone PosD. According to one aspect, the refined position PosA corresponds to the local position PosL.

[0072] Obtaining such a refined position PosA has many advantages. This can be used with great confidence to display the position of the flying apparatus 3 on the display device of the computer 10, in particular, associated with the position of the drone PosD. This allows reactive and continuous monitoring by the operator.

[0073] This further makes it possible to provide a refined position PosA to the ground interception device 13 to carry out a targeted interception.

[0074] In this example, the method comprises a tracking step E8 consisting of automatically moving the tracking drone 2 as a function of the local position PosL, preferably without taking into account the target position PosC. During this step, the tracking drone 2 pursues the flying apparatus 3, from the local position PosL and the detection vector Vd while maintaining a safety distance with the flying apparatus 3. This allows the tracking drone 2, advantageously, to pursue the flying apparatus 3, even in the event of a malfunction of the monitoring device 11 of the ground station 1.

[0075] Preferably, the method comprises a step consisting of controlling E9 the interception device 23 of the tracking drone 2 so that it targets the flying apparatus 3 at the local position PosL. In this example, with reference to [Fig. 10], the tracking drone 2 carries out an interception with a short-range jammer which makes it possible to prohibit any control of the flying apparatus 3 remotely. The flying apparatus 3 is in a safety position and remains in suspension and can no longer approach the site to be protected SAP. The short-range jammer can also hack the flying apparatus 3 in order to force its landing. Such a short-range jammer makes it possible to avoid any collaterality.

[0076] The tracking drone 2 can also carry out a destructive interception in a targeted manner, for example, by means of a laser. A targeted interception at a short distance is more reliable. Once the interception has been carried out, the tracking drone 2 can return to its storage area, in particular, automatically.

Claims

Claims

1. System (S) for detecting a flying device (3) in an airspace (EA), the detection system (S) comprising at least one ground station (1) and at least one tracking drone (2), • the ground station (1) being configured to: • detect a position of at least one flying device (3) in the airspace (EA), hereinafter “target position” (PosC), • transmit the target position (PosC) to the tracking drone (2), • the tracking drone (2) being configured to move automatically to the target position (PosC), the tracking drone (2) comprising a lidar, • the tracking drone (2) being configured to: • measure by means of the lidar a detection vector (Vd) of at least one flying device (3) in a vicinity (5) of the tracking drone (2), the detection vector (Vd) comprising measurements of distance, speeds and accelerations along three axes • detect the position of the at least one flying device (3) in,hereinafter “local position” (PosL), from the position (PosD) of the tracking drone (2) and the detection vector (Vd), • transmit the local position (PosL) to the ground station (1), • the ground station (1) being configured to: • determine a refined position (PosA) from the local position (PosL).,

2. System according to claim 1, wherein the ground station (1) comprises a monitoring device (11) for detecting the target position (PosC), in particular, a long-range radar.

3. The system of claim 1, wherein the lidar (22) has a horizontal aperture angle greater than 70 degrees and a vertical aperture angle greater than 70 degrees.

4. System according to one of claims 1 to 3, in which the tracking drone (2) comprises an image capture device configured to continuously transmit the captured images (Im) to the ground station (1).

5. System according to one of claims 1 to 4, comprising an interception device (23), in order to intercept the flying apparatus (3) at the refined position (PosA).

6. The system of claim 5, wherein the interception device (23) is mounted on the tracking drone (2).

7. Method for detecting a flying apparatus (3) in an airspace (EA) by a detection system (S) according to one of claims 1 to 6, the detection system (S) comprising at least one ground station (1) and at least one tracking drone (2), the method comprising steps consisting of: • Detecting (El), by the ground station (1), a position of at least one flying apparatus (3) in the airspace (EA), hereinafter "target position" (PosC), • Transmitting (E2), by the ground station (1), the target position (PosC) to the tracking drone (2), • Automatically moving (E3) the tracking drone (2) to the target position (PosC), • Measuring by means of the lidar a detection vector (Vd) of at least one flying apparatus (3) in a vicinity (5) of the tracking drone (2), the detection vector (Vd) comprising distance measurements,of speeds and accelerations along three axes • Detect (E4) the position of at least one flying device (3) in, hereinafter “local position” (PosL), from the position (PosD) of the tracking drone (2) and the detection vector (Vd), • Transmit (E6), by the tracking drone (2), the local position (PosL) to the ground station (1), and • Determine (E7), by the ground station (1), a refined position (PosA) from the local position (PosL).,

8. A method according to claim 7, comprising a step of controlling (E9) an interception device (13, 23) so that it targets the flying apparatus (3) at the refined position (PosA).

9. Method according to one of claims 7 to 8, in which the refined position (PosA) is displayed on a display screen of the ground station (1).

10. Method according to one of claims 7 to 9, wherein a position (PosD) of the tracking drone (2) is continuously determined by the tracking drone (2), and sent to the ground station (1).

11. Method according to one of claims 7 to 10, in which the refined position (PosA) is determined from the target position (PosC) and the local position (PosL).

12. Method according to one of claims 7 to 11, wherein the target position (PosC) is detected and transmitted to the tracking drone (2) continuously.

13. Method according to one of claims 7 to 12, comprising a step (E5) consisting of comparing a separation distance (EC), determined between the local position (PosL) and the target position (PosC), with a neighborhood threshold (Sv), the tracking drone (2) transmitting (E6) the local position (PosL) only if the separation distance (EC) is less than the neighborhood threshold (Sv).

14. Method according to one of claims 7 to 13, comprising a tracking step (E8) consisting of automatically moving the tracking drone (2) as a function of the local position (PosL) and the detection vector (Vd) defined between the tracking drone (2) and the flying device (3), preferably without taking into account the target position (PosC).

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