Methods, and apparatus for configuration and error correction of a projectile launching device

Abstract

A computer-implemented method for updating a configuration of a projectile launching device, the method comprising: determining a location of a target; determining a configuration of the projectile launching device to propel a projectile to collide with the target; receiving first data from a first passive sensor; determining a location of the propelled projectile based on the first data; and updating the configuration of the projectile launching device based on a determined relative difference of the location of the target and the location of the propelled projectile.

Description

Technical Field

[0001] The present disclosure generally relates to improving the configuration of projectile launching devices. In particular, the present disclosure relates to methods, systems, and computer program product for verifying and improving the configuration of a projectile launching device in view of a detected possibly moving target.Background

[0002] In the context of Counter Unmanned-Aircraft Systems (C-UAS), new threats such as small and agile drones, are imposing a big risk. These new threats are hard to detect because of their small size, their low radar cross section, and their low signal-to-noise ratio, Moreover, these new threats can be very fast: drones for example may reach up to hundreds of km / h. Additionally, these new threats may be hard to hit because in addition to the small size and high speed, they can perform effective evasive manoeuvres.

[0003] Currently, the threats from these new threats are countered using costly air defence missiles that may cost multiple hundreds of thousands of Euros. However, these new threats, and drones in particular, may cost at most tens of thousands of Euros; therefore, they put defenders in an economically asymmetric position.

[0004] Hence, there is a need to develop low-cost detection systems to detect and track new threats, like drones. Further detection and tracking should be combined with effectors that using low-cost ammunitions that may be able to damage or destroy the detected target.Summary of the Invention

[0005] The present invention is defined in the independent claims. The dependent claims recite selected optional features. In the following, each of the described methods, systems, apparatuses, examples, and aspects, which do not fully correspond to the invention as defined in the claims is thus not according to the invention and is, as well as the whole following description, present for illustration purposes only or to highlight specific aspects or features of the claims.

[0006] According to a first aspect of the present disclosure, there is provided a computer-implemented method for updating a configuration of a projectile launching device. The method comprises determining a location of a target; determining a configuration of the projectile launching device to propel a projectile to collide with the target. The method may further include receiving first data from a first passive sensor and determining a location of the propelled projectile based on the first data. Further, the method may include a step of updating the configuration of the projectile launching device based on a determined relative difference between the location of the target and the location of the propelled projectile.

[0007] The method is directed to the updating of the configuration of the projectile launching device to hit a potentially moving target. The updated configuration may point the projectile launching device towards the target to enable the projectile may hit the target. The update of the configuration may be based on a first data that may indicate the location of the propelled projectiles. The determination of a relative difference between the location of the target and the location of the propelled projectile provides an indication of how much propelled projectiles missed the target. Based on this latter indication, the configuration of the projectiles launching device may be updated.

[0008] In some examples, the method may further comprise that the projectile launching device may be configured to propel one or more projectiles to the target.

[0009] The number of projectiles to propel may be specified in the configuration, or the number of projectiles to propel may be pre-determined, determined by the computing device or by other components in the weapon station.

[0010] In some examples, the method may further comprise determining the location of the target based on the first data and / or based on second data received from the first passive sensor and / or a second passive sensor.

[0011] The location of the target and / or projectiles may be determined based on sensor data, for example from the first or a second passive sensor. However, the location of the target may also be predetermined, for example when external knowledge is available, or an indication of the location of the target and of the projectiles may be received from a different system component.

[0012] In some examples, determining the location of the target and / or the propelled projectile may further comprise estimating a trajectory and / or a future location of the target and / or the propelled projectile, in particular by tracking a target trajectory and / or a propelled projectile trajectory, more particularly by extrapolating the tracked target trajectory and / or the tracked propelled projectile trajectory.

[0013] The determination of the location of the projectile or of the target may be based on the sensor data. The determination may be performed by tracking the location of the target or of the propelled projectiles for example by using a tracking process that may be based on a single object tracking, where the tracking process may be based on observations or data produced by the first passive sensor 112. In other words, the tracking process may observe changes in the sensor data over time, these changes may indicate movements of the projectiles or of the target. Alternatively, the location of the projectiles or of the target may be extrapolated based on the sensor data.

[0014] The direction and speed of movement of the target and / or of the propelled projectile may also be based on changes in the sensor data indicating the coordinates of the target and / or of the propelled projectile over time, In examples in which the sensor is an electrooptical sensor and the data images, the direction and speed of movement of the target and / or of the propelled projectile may be based on one or more changes in the image coordinates of the target and / or of the propelled projectile(s) over time.

[0015] In some examples, the tracked target trajectory and / or the tracked propelled projectile trajectory may be extrapolated. Extrapolating may comprise estimating a direction and speed of movement of the target and / or of the propelled projectile and preferably further comprise estimating at least one of: an aerodynamic drag of the propelled projectile, a drop of the propelled projectile, and atmospheric conditions.

[0016] The extrapolation of the trajectory of the target may be based on the direction and speed of travel of the target at the first location in combination with a determined time interval. However, the extrapolated trajectory of travel may be determined in other ways. For example, a model of behaviour of the target may be used to estimate the expected direction of travel and expected speed of the target while the target moves to the location. Behavioural models may be based on knowledge of behaviour of the target and / or learned based on AI based models.

[0017] The extrapolated trajectory of the projectiles may be based on a ballistic model of the propelled projectile, where the ballistic model may include data related to the propelled projectile including parameters such as weight and drag, and environmental parameters related to atmospheric conditions that may comprise one or more of a humidity, an air pressure, and / or a wind. The Ballistic Model that may also include the projectile launching device and projectile statistics to provide a lead angle with aim correction which compensates drag, projectile drop and target motion to reliably hit the target.

[0018] Alternatively, the trajectory of the target and the projectiles may be determined by a tracking process using sensor data to track the location of the target and / or of the projectiles over time.

[0019] In some examples, the relative difference of the location of the target and the location of the propelled projectile is determined based on a comparison of the determined, in particular estimated, future locations of the target and of the propelled projectile.

[0020] The relative difference may be defined as the difference between the location of the projectile and the location of the target. This relative difference can be the result of a configuration error or configuration problem of the projectile launching device, and / or due to atmospheric conditions such as the presence of wind, and / or due to sudden movements of the target.

[0021] In some examples, the relative difference of the location of the target and the location of the propelled projectile is determined based on a determined, in particular estimated, future 2D location of the target and a determined, in particular estimated, future 2D location of the propelled projectile.

[0022] The error may be detected in a 2D space where one dimension may indicate the altitude of the target above or below the projectile launching device and the second dimension may indicate the location of the target left or right of the projectile launching device.

[0023] In some examples, updating the configuration of the projectile launching device may comprise determining a desired trajectory of the propelled projectile from the projectile launching device to a location vertically above the determined, in particular estimated, future location of the target and / or horizontally in front the determined, in particular estimated, future location of the target in a direction of movement of the target; and determining pan and tilt angles of the projectile launching device based on the determined trajectory.

[0024] In this way, the projectile launching device aims at shooting in front of the target, to account for the target motion, and above the target, to account for gravity. The respective desired projectile trajectory has its origin at this "in front and above" point and at further distance should intersect with the target.

[0025] Updating the configuration of the projectile launching device may include determining the tilt and pan angles to match the desired trajectory of the propelled projectile.

[0026] In some examples, determining the relative difference as one or more angles, preferably a vector of lateral and elevation angles, between the determined trajectory of the propelled projectile; determining a correction pan based on a horizontal component, preferably a lateral angle, of the determined relative difference; and determining a correction tilt as a vertical component, preferably an elevation angle, of the determined relative difference; wherein determining pan and tilt angles of the projectile launching device further based on the determined correction pan and correction tilt angles.

[0027] The determination of the relative difference of the projectile result in an angle in 2D or 3D and this angle may be transformed in a correction to be applied to the projectile launching device by projecting the 2D / 3D angle in the vertical and horizontal components to determine the correction tilt and pan angles.

[0028] In some examples, the propelled projectile is a tracing projectile; and the first data and / or second data comprises information about a trace of the propelled projectile.

[0029] Tracing projectiles, also referred to as tracer ammunition, leave a trace indicating their trajectory. The passive sensor may follow the trace to detect the location of the projectiles and where they are moving to.

[0030] If the passive sensor is a camera, the first data may comprise an image or a sequence of images indicating the location of the propelled projectile. The derived information may be an image indicating the visible trace of the propelled projectile.

[0031] In some examples, the first and / or second passive sensors comprise an electrooptical sensor; and the first and / or second data includes one or more images.

[0032] The passive sensor may be any passive sensor but preferably an electrooptical sensor and the data, including the first data, may include one or more images taken from the electrooptical sensor.

[0033] In some examples, determining the location of the target comprises determining a type of the target, in particular a physical size of the target; and calculating the desired trajectory and / or a distance between the passive sensor and the target based on the type, in particular the physical size, of the target. Calculating the desired trajectory and / or distance may further be based on the dimensions of the target in the image, and intrinsic and / or extrinsic parameters of the passive sensor.

[0034] The determination of the type of the target may also enable the determination of the of the physical dimensions of the target based on some list of the possible targets, where the list may be a database of targets, or the list may be implicit in a classification system that given the image of the target reports the target type.

[0035] The determination of the physical dimensions of the drone may enable the determination of the location of the drone in a 3D space.

[0036] It is preferred to determine a bounding box enclosing the target based on the first data. This allows determining the dimensions the target in the image. It is further preferred to determine locational information based on the dimensions the target in the image and the physical dimensions of the target. The locational information is preferably indicative of a distance between the passive sensor and the target.

[0037] Determining the first location preferably includes processing the first data by a single object tracking algorithm. The single object tracking algorithm may determine the bounding box.

[0038] In some examples, determining a location of the propelled projectile in the first data comprises detecting points in the first data with brightness values that exceed a predetermined threshold, and determining the location based on the detected points. The method preferably comprises: applying a threshold to the colours and brightness values of the one or more images of the first data; optionally applying an extreme darker colour or an extreme brighter colour to all areas of the image with colour and brightness values that are below the applied threshold; detecting the points in the image and determining the location of the propelled projectile based in the detected points.

[0039] Tracer ammunition may be detected either by a neural network detecting bright spots in an image or by preprocessing images and binary thresholding of colour values, i.e. set them to either 0 or 255 given a high value threshold (e.g. 200).

[0040] In some examples, the target may be an unmanned aerial vehicle, such as a drone.

[0041] The invention may relate to drones, but other targets may also be possible, such as stationary sensors or non-stationary manned or unmanned devices.

[0042] According to a second aspect of the present disclosure, there is provided a system comprising one or more processors and one or more storage devices, wherein the system is configured to perform the computer-implemented method of any preceding examples.

[0043] According to a third aspect of the present disclosure, there is provided a computer program product for loading into a memory of a computer, comprising instructions, that, when executed by a processor of the computer, cause the computer to execute a computer-implemented method of any of the preceding examples.Brief Description of the Drawings

[0044] The features, objects, and advantages of the present disclosure will become more apparent from the detailed description set forth below when taken in conjunction with the drawings in which like reference numerals refer to similar elements. Fig. 1 is a schematic drawing illustrating an exemplary weapon station; Fig. 2 is a schematic drawing illustrating the detection of a target in a first location and the prediction of a second location of the target; Fig. 3 is a schematic top view of an exemplary configuration of the projectile launching device; Fig. 4 is a schematic side view of the exemplary configuration of the projectile launching device; Fig. 5 is a schematic drawing illustrating the relative difference of the location of the target and the location of the propelled projectile; and Fig. 6 is a flow chart of an example of a method of determining a configuration of a projectile launching device. Detailed Description of Exemplary Embodiments

[0045] Fig. 1 schematically illustrates an exemplary weapon station 110.

[0046] The weapon station 110 may include at least one passive sensor 112, a computing device 114, and a projectile launching device 116. The passive sensor 112 may be communicatively coupled with the computing device 114 and in turn the computing device 114 may be communicatively coupled with the projectile launching device.

[0047] The passive sensor 112 may perform one or more observations of the environment within a range of view 130 that may depend on the sensor. Further, the passive sensor 112 may produce data codifying the observations performed and transmit the data to the computing device 114.

[0048] When an exemplary target 140 is present in said range of view 130, then passive sensor 112 may observe and detect target 140 and produce first data about the target 140. In particular, the first data may be indicative of the target 140.

[0049] Passive sensors, such as sensor 112, are sensors that may detect signals or energy emitted or reflected directly or indirectly by objects in the range of view of the sensor. Passive sensors differ from active sensors, such as radars that actively transmit energy to detect objects. Since passive sensors do not transmit any signals or any energy, but rather passively detect signals produced by other objects, enemy objects may not detect any signal revealing the existence of the passive sensor, thus passive sensors tend to be invisible to enemy objects.

[0050] Examples of passive sensors may include electro-optical sensors, such as a camera for visible or infrared light. Other examples of passive sensors may include inter alia microphones for noise sensing, thermal sensors, sensors detecting changes in the electric field, sensors detecting chemical compounds, or seismic sensors. An additional example of passive sensor1 10 may be a sensor network of passive sensors, where the data collected by the sensors may provide information about a range of view 130.

[0051] The data produced by the passive sensor 112 may depend on the type of sensor. In the specific case of electro-optical sensors, the first data produced may include one or more images. Passive sensor data, such as the first data, may also include meta-data about the data. Examples of meta-data may include extrinsic parameters such as temporal or location information indicating when and where the data has been collected. Other types of meta-data may include intrinsic parameters of the sensor. In the exemplary case of electro-optical sensors, intrinsic sensors parameters may include inter alia focal length, aperture, field-of-view, resolution.

[0052] The computing device 114 may be configured to receive data about target 140 from the passive sensor 112 and process the received data. The data transmission from the passive sensor 112 to the computing device 114 may be based on different protocols. In some cases, the passive sensor 112 may stream data to the computing device 114, enabling the passive sensor 112 to perform an observation, and immediately transmit the data related to the observation to the computing device; thus, tightly coupling data sensing and processing. However, the data transfer may also be based on other protocols that may enable data transfer in batches to be processed serially, or other transfer processes or policies may be utilized depending on the specific application requirements.

[0053] Upon receiving data from the passive sensor, the computing device 114 may process the data. Such processing may include determining whether the target 140 may pose a threat, estimating the location and movement of the target 140 and estimating how to configure the projectile launching device 116 to hit and disable the target 140.

[0054] The computing device 114 may include one or more physical and / or virtual computing platforms that may preferably be in the proximity of the passive sensor 112; but it may also be in a cloud geographically distant from the passive sensor 112. The computing device may also be a hybrid combination of local computing platforms, such as a computer positioned in the proximity of the passive sensor 112, and virtual computers distributed in geographically distinct clouds.

[0055] The computing device 114 may also include any type of physical computing platforms including single board computers, mobile devices, and / or tablets. The computing device may be a computing platform embedded in the passive sensor 112 or in the projectile launching device, or embedded in other components that may be included in the weapon station. The computing device 114 may also be embedded in one or more devices of the weapon station 110. For example, functionalities related to the sensor data processing may be embedded in the passive sensor 112, while the functionalities related to the configuration of the projectile launching device may be embedded in the projectile launching device itself.

[0056] The projectile launching device may include a launcher emitting, for example propelling, projectiles. More generally, a projectile launching device may be a weapon and the launcher may be the barrel of the weapon. Examples of projectile launching devices may include any device configured to launch visible, in particular traceable, ammunition, such as a machine gun, a cannon, or a grenade launcher for unpropelled grenades. Since the projectiles are propelled by the launcher in these cases, the disclosed projectile launching device may reduce the cost and complexity of the weapon station, and in particular the cost and complexity of the projectiles may be reduced because the projectiles may not require complex hardware or software to pursue their target as well as hardware and software to be self-propelled. The projectile launching device may also comprise a launcher for an unguided propelled projectile, such as a rocket-propelled grenade, or an unguided rocket.

[0057] The coupling between the passive sensor 112, the computing device 114, and the projectile launching device 116 may be based on any network configuration that may enable data transmission. Thus, the coupling may be based on wired or wireless networking; it may further be based any Local Area Network infrastructure, Wide Area Network infrastructure, or Satellite communication infrastructure.

[0058] The passive sensor 112, the computing device 114 and the projectile launching device 116 may be tightly connected and be partially or entirely embedded systems. Thus, for example, the passive sensor may be placed on the projectile launching device or embedded in the projectile launching device. Similarly, the computing device may be an embedded system. Thus, the coupling between the components of the weapon station 110 may be at least partially based on a network on chip communication system as well as any on-chip or peripheral communication infrastructure.

[0059] Fig. 2 illustrates the detection of target 140 in a first location and the prediction of a second location of the target 140. Fig. 2 analogously to Fig. 1 includes the weapon station 110 which in turn includes the passive sensor 112, the computing device 114 and the projectile launching device 116 as discussed above. The passive sensor 112 may detect the target 140 and may transmit first data about the target 140 to the computing device 114 that is coupled with the passive sensor 112.

[0060] The first data may be transmitted from the passive sensor 112 to the computing device 114 which may be included in or external to the passive sensor 112. At the computing device 114, the first data may be subject to a detection and / or tracking process, such as a single object tracking (SOT) process to track objects detected by the passive sensor 112, such as target 140. The tracking process may be performed by the passive sensor 112 or by the computing device 114 that may provide to the passive sensor 112 and / or a steering device of the passive sensor indications to track the target 140 and / or indications on how to modify the range of view of passive sensor 112 to track the target 140.

[0061] Upon receiving the first data from the passive sensor 112, the computing device 116 may attempt to recognize the target 140 and determine a type of target 140. This determination may be part of SOT, and it may be based on a pretrained AI recognition / classification model. Further, based on the recognition of the target 140 and of its type, the computing device 114 may determine whether the target 140 may poses a threat.

[0062] The determination of the type of the target 140 may also enable the determination of the properties of the target 140, such as its physical size, and other properties. This determination may be based on a list of known targets, such as a list of known drones and their properties. This list may be a lookup table or a database including information about drones, or the list may be implicit in the AI recognition / classification model.

[0063] The determination of the physical size of target 140 may enable the determination of the location 232 of the target 140 and the determination of the direction and velocity of movement of the target 140. The determination of the location and movement of the target 140 may be based on the determined physical size of target 140, the features of the target 140 in the data and on the properties of the passive sensor.

[0064] If for example, the passive sensor is an electrooptical sensor, preferably an infrared camera; the data includes one or more images. The determination of the type of the target 140 may be based on the application of image recognition, which may be based on a pre-trained AI recognition / classification model. The AI model may also provide information such as the physical size of target. The calculation of the size of target 140 in the image may be performed by computing the bounding box of the target in the image. The location of the target 140 may be estimated based on the extrinsic parameters of the electrooptical sensor such as location and orientation and intrinsic parameters of the electrooptical sensor such as focal length, the field of view, aperture, resolution.

[0065] The computing device 114 may determine that target 140 has been detected at location 232. Location 232 may be considered a first location of target 140. This location may correspond to the location of target 140 at a first instant, which may be the instant in which target 140 has been detected by the passive sensor. The computing device may also determine a second location 234, that may correspond to a location that the target 140 may occupy at a second instant, which may temporally follow the first instant, in other words the second instant is in the future with respect to the first instant.

[0066] The second location 234 of the target 140 may be determined based on the current location 232 of the target 140 and knowledge about the target 140 such as current velocity and direction of motion 242 of the target 140 and an expected motion of the target 140. In case the expected motion of the target 140 may be assumed to be constant in direction and velocity, thus the second location may be estimated based on the physical laws of motion. However, other estimation methods may be used such as method referring to behavioural models that may attempt to predict unexpected changes of direction and velocity of the target 140. The second location may also be extracted from a Kalman filter that may also be used to improve the reliability of the passive sensor data.

[0067] The estimate of the second location may also depend on a determination of the second instant that may specify when to aim at the target 140. The second instant may need to be sufficiently far in the future to take into account possible delays due to the reconfiguration of the projectile launching device, thus, enabling the projectile launching device to reconfigure and to aim to the target 140.

[0068] Upon determining the second location, the computing device may determine one or more configurations of the projectile launching device so that the projectile launching device may point to the target 140 and propel projectiles to collide with and disable the target 140.

[0069] Fig. 3 is a schematic top view of an exemplary configuration 310 of the projectile launching device 116, where the direction of view is indicated by coordinate system 312. Fig. 3 relates to the pointing of the launcher included in the projectile launching device 116 to the target 140 with the objective to hit target 140 and disable it.

[0070] Fig. 3 relates to the horizontal rotation of the launcher of the projectile launching device 116. In Fig. 3, line 311 may represent a first position of the launcher, while line 313 may represent a target position of the launcher. Angle 316 may be considered to be the pan angle of the launcher indicating the deviation between two positions of the launcher in a horizontal direction.

[0071] Fig. 4 is a schematic side view of the exemplary configuration 310 of the projectile launching device 116 that illustrates vertical rotation of the launcher of the projectile launching device 116. The direction of view is indicated by coordinate system 322. Line 321 may represent a possible first position of the launcher of projectile launching device 116. Furthermore, line 323 may represent the target position of the launcher of projectile launching device 116. Angle 326 may represent the tilt angle of the launcher of the projectile launching device 116, where the tilt angle may indicate the deviation between the first and the second position of the launcher of device 116 in a vertical direction.

[0072] The determination of the configuration of the projectile launching device 116 may include the determination of the pan and tilt angles that match the expected trajectory of a trajectory of the propelled projectiles from the projectile launching device towards one of the second locations where the target 140 is expected to be.

[0073] The determination of the trajectory of the projectile may be based on the second location 234 and on at least one of: an aerodynamic drag of the projectile, a drop of the projectile, and atmospheric conditions, where the atmospheric conditions may include one or more of a humidity, an air pressure, and / or a wind.

[0074] The determination of the trajectory of the projectiles may be based on a ballistic model of the projectiles that may leverage the trajectory of the target 140 and on additional projectile launching device and projectile statistics to provide pan and tilt angles with aim correction which compensates drag, projectile drop and target motion to reliably hit the target.

[0075] Configuring the projectile launching device may further include estimating an execution time. The execution time may be a function of the sum of: the time required to execute the rotation from the current position to the target position of the projectile launching device, an estimate of the lock time that is the time that the propelling mechanism of the projectile launching device requires to propel the projectile. The lock time may also be defined as the time required to propel the projectile, e.g., the time of rotation of a firing pin or a bolt of a gun, and the projectile's time of flight from the projectile launching device 116 to the second location 234 of the target 140.

[0076] Configuring the projectile launching device may include an abort condition in case the execution time may be shorter than the available time until the target 140 may be expected to be at the second position 234. The available time may be determined as the difference between the second instant and the first instant as described with reference to Fig. 2.

[0077] An estimate of the rotation time of the projectile launching device may be further decomposed in estimating a tilt rotation time that may be the time required to perform the determined tilt rotation; and the pan rotation time that may be the time required to perform a pan rotation. The total rotation time of the projectile launching device may depend on the process of rotation of the device. For example, if the device rotates in a first direction, which may be the horizontally, or pan direction, and then in a second direction, which may be a vertically, or tilt direction, then the total rotation time may be a function of the sum of the pan and tilt rotation times. If instead the device rotates in both directions concurrently, then the time of rotation may be a function of the maximum of the pan or tilt rotation times. Additionally, other rotation policies may be used that may lead to other rotation time estimation functions to be used.

[0078] Once completed, the configuration parameters may be transmitted to the projectile launching device 114 that could proceed to execute the received configuration and propel the projectiles towards the target 140.

[0079] The passive sensor 112 may be further configured to perform at least one second observation directed to target 140 and thereby generate second data. The second data may have a format similar to the first data. The computing device may then receive the second data from the passive sensor. Based on the second data, the computing device may determine a new location of the target 140 according to the second data and determine whether the second data is indicative of any damage to the target 140. Further, the second data may provide the basis for a decision as to whether to further damage the target 140 or whether the target 140 was already damaged or destroyed.

[0080] Fig. 5 is a schematic drawing illustrating the relative difference 580 of the location of the target 140 and a location of the propelled projectile 570. In Fig. 5, are illustrated the projectile launching device 116, a projectile 570 propelled by the projectile launching device 116 and an effective trajectory 560 of the projectile 570. Fig. 5 also illustrates the target 140 and a desired trajectory 550 of projectile 570. The desired trajectory 550 differs from the effective trajectory 560 of projectile 570. The relative difference 580 of the location of the target 140 and the propelled projectile 570 may be estimated as the distance between the location of the target 140 and the closer location of the projectile 570 to the target 140 while the projectile moves along the effective trajectory 560.

[0081] The relative difference 580 may be due to a systematic error that may depend on uncertainty in the atmospheric conditions, uncertainty related to the movements of the target 140 as well as uncertainty in the transformation from a configuration to the position of the projectile launching device 116. The uncertainty in the transformation from a configuration to the position of the projectile launching device 116 may for example be due to small mechanical errors of positioning of the launcher 313, 323 of the projectile launching device 116, and consequently in propelling the projectile away from the target 140.

[0082] Estimating the relative difference 580 may require detecting the effective trajectory 560 of the projectile 570, and then providing a measure of the distance between the effective trajectory 560 and the location of the target 140. A way for detecting the effective trajectory 560 of the projectile 560 may be to utilize a tracing projectile, in other word a projectile that may leave a trace indicating its position and its trajectory after leaving the projectile launching device 116. For example, a common type of tracing projectile may leave a visible trace. Following the visual trace may be possible to detect the successive locations of the projectile and where they are moving to.

[0083] The computing device 114 may also receive second data from the passive sensor 112. The second data may include information about the target and information about the trace produced by the tracking projectile 570. Said trace may provide an indication of the effective trajectory 560 followed by the projectile 570.

[0084] In some examples, the passive sensor 112 may be an electrooptical sensor, the second data from the passive sensor 112 may include an image or a sequence of images depicting both the target and at least some portions of the visible trace produced by the tracing projectile. The visible trace may then indicate a sequence of locations of the projectile 570.

[0085] The relative difference 580 between the location of the target 140 and the propelled projectile may be determined based on an estimate of the distance between target 140 and the visible trace indicating the estimated projectile trajectory 550 of the projectile 570. Since the projectile may be assumed to have been in any of the points indicated by the visible trace, the error 580 may be computed as the distance between the closest location of the projectile 580 to the target 140.

[0086] The relative difference 580 may be measured in terms of the number of degrees of the angle 540 between the effective trajectory 560 of the projectile 570 as indicated by the visible trace and the desired trajectory 550 to the target 140. The determined relative difference 580 may be converted into degrees of pan and tilt angle corrections on which corrections of the configuration of the projectile launching device 116 may be based. The conversion may be based on determining a correction pan as the horizontal component of the determined error; and determining a correction tilt as the vertical component of the determined error. The correction of the tilt and pan angles may be applied to successive configurations of the projectile launching device 116.

[0087] The computation of the relative difference 580 may be performed in 3D or in 2D. The 3D computation may be performed by estimating the distance between the projectile launching device 116 and the target140, and the direction of the target 140 in relation to the projectile launching device 116. However, the computation of the distance may add complexity and consequently time and / or inaccuracies to the computation of the configuration of the projectile launching device 114.

[0088] Alternatively, the computation of the relative difference 580 may be performed in 2D without any estimate of the distance from the projectile launching device 114 to the target 140. Computing the relative difference 580 in 2D may reduce the computation requirements. In addition, it may enhance accuracy with respect to estimating the projectile locations, in particular as computational errors when projecting the 2D locations to a 3D space are avoided. Hence, computing the relative difference 580 in 2D may provide a more effective strategy.

[0089] To further damage the target, the computer-implemented method may further include determining at least one third location based on the second location and / or the new location of the target. The third location may be the next location where to attempt to hit and damage the target. The third location may be further associated to a third instant, where the third instant temporally follows the second instant.

[0090] The third location may then be considered to be analogous to the second location in the sense that the computing device may project a trajectory of the propelled projectiles to the third location and specify a new configuration of the projectiles launching device to hit the target at the third location according to the methods disclosed in relation to the second location. The new configuration may take into account the relative difference 580 and the correction of the tilt and pan angles with the objective to reduce the relative difference 580 in the following propulsion of the projectile 570 and increase the likelihood of hitting the target.

[0091] The third location may implicitly trigger an iterative process in which the passive sensor detects the target, the computing device projects the location of the target in the future and determines a configuration of the projectile launching device to disable the detected in the third location and measures the relative difference 580 to improve future propulsion of the projectile. 570. Although as discussed above this disclosure applies to any passive sensor that may provide information about the target 240 and information about the effective trajectory of the projectile 260 In a preferred embodiment, the passive sensor comprises an electrooptical sensor, preferably the passive sensor may be an infrared camera; and the data points are images or temporal sequences of images.

[0092] The passive sensor may be any passive sensor but preferably it may be an electrooptical sensor and the data, including the first and second data, includes one or more images taken from the electrooptical sensor.

[0093] The use of electrooptical sensors enables the computing device to determine the position of the target given one or more images. Upon receiving the images from the electrooptical sensor the computing device 114 may determine a type of the target; and determine the physical dimensions of the target based on the type of the target. The determination of the type of the target may be based on a list of targets including information about targets, where the information may include inter alia the physical dimensions of the targets. The computing device 114 may then compare the dimensions of the target in the image with the retrieved physical dimensions of the target and derive the distance of the target from the passive sensor 112 based on the passive sensor 112 intrinsic and extrinsic parameters. It may further be preferred to determine a bounding box enclosing the target based on the first data. This allows determining the dimensions the target in the image.

[0094] The position of the target may also be determined by a computing process based on a single object tracking (SOP) process based in an SOP algorithm that upon receiving images from the passive sensor may derive the position of the target and predict the path of the target. The SOP process may also determine the bounding box. It is worth noting that although SOP algorithms are usually defined based on images received from electrooptical sensors, the SOP process may be based on data received from any type of passive sensor to the extent that a location of the target may be derived from the data provided by the passive sensor.

[0095] The determination of a location of the propelled projectile in the first data may include increasing the contrast between the colours in the images with the objective to highlight the trace of the projectile 570. This process may include the determination of a threshold (e.g. 200) to the colours and brightness values to the one or more images of provided by the image sensor, followed by the application of extreme dark colours or an extreme bright colours to all areas of the image with colours and brightness values that are below the applied threshold; and, conversely applying the opposite transformation to the areas of the image that are above the threshold. A neural network or image processing may then be used to determine the trace of the projectile 570. The method of any preceding claim, wherein the target is a drone.

[0096] Fig. 6 illustrates an example of a method 600 of determining a configuration of a projectile launching device. Method 600 may be executed by the computing device 114 of the weapon station.

[0097] In step 610, the computing device determines a location of a target 140. The determination may be based on information provided by the passive sensor 112.

[0098] In step 620, the computing device 114 determines a configuration of the projectile launching device 114 to propel a projectile to collide with the target 140. The determination of the configuration may be based on a determination of the location where to propel the projectile, and a determination of the position of the projectile launching device.

[0099] At step 630, the computing device may receive first data from a passive sensor. The first data may be indicative of the position of the propelled projectile 570

[0100] At step 640, the computing device determines a location of the propelled projectile based on the first data. The location may be determined by following the trace of the projectile.

[0101] At step 650, the computing device updates the configuration of the projectile launching device based on a determined relative difference of the location of the target and the location of the propelled projectile. The update of the configuration may be based on a correction of the pan and tilt angles of the projectile launching device 116.Reference signs

[0102] 110Weapon station 112Passive sensor 114Computing device 116Projectile launching device 130Range of view 140Target 232First Location 234Second location 242Direction of motion 310Configuration 311Lateral position at first position 312Coordinate system 313Lateral position at target position 316Pan angle 321Elevation at first position 322Coordinate system 323Elevation at target position 326Tilt angle 540Angle between the effective trajectory and the desired trajectory 550Desired trajectory 560Effective trajectory 570Projectile 580Relative difference 600Method 610-650Steps of method 600

Claims

1. A computer-implemented method for updating a configuration of a projectile launching device, the method comprising: determining a location of a target; determining a configuration of the projectile launching device to propel a projectile to collide with the target; receiving first data from a first passive sensor; determining a location of the propelled projectile based on the first data; and updating the configuration of the projectile launching device based on a determined relative difference of the location of the target and the location of the propelled projectile.

2. The method of claim 1, further comprising: determining the location of the target based on the first data and / or based on second data received from the first sensor and / or a second sensor.

3. The method of any preceding claim, wherein determining the location of the target and / or the propelled projectile further comprises estimating a trajectory and / or a future location of the target and / or the propelled projectile, in particular by tracking a target trajectory and / or a propelled projectile trajectory, more particularly by extrapolating the tracked target trajectory and / or the tracked propelled projectile trajectory.

4. The method of claim 3, wherein extrapolating the tracked target trajectory and / or the tracked propelled projectile trajectory comprises estimating a direction and speed of movement of the target and / or of the propelled projectile and, preferably, further comprises estimating at least one of: an aerodynamic drag of the propelled projectile, a drop of the propelled projectile, and atmospheric conditions.

5. The method of claim 3 or claim 4, wherein the relative difference of the location of the target and the location of the propelled projectile is determined based on a comparison of the determined, in particular estimated, future locations of the target and of the propelled projectile.

6. The method according to any preceding claim, wherein the relative difference of the location of the target and the location of the propelled projectile is determined based on a determined, in particular estimated, future 2D location of the target and a determined, in particular estimated, future 2D location of the propelled projectile.

7. The method of any of claims 3 to 6, wherein updating the configuration of the projectile-launching device comprises: determining a desired trajectory of the propelled projectile from the projectile launching device to a location vertically above the determined, in particular estimated, future location of the target and / or horizontally in front the determined, in particular estimated, future location of the target in a direction of movement of the target; and determining pan and tilt angles of the projectile launching device based on the determined desired trajectory of the propelled projectile.

8. The method of the preceding claim, further comprising: determining the relative difference as one or more angles, preferably a vector of lateral and elevation angles, between the determined trajectory of the propelled projectile and the desired trajectory of the propelled projectile; determining a correction pan based on a horizontal component, preferably a lateral angle, of the determined relative difference; and determining a correction tilt as the vertical component, preferably an elevation angle, of the determined relative difference; wherein determining pan and tilt angles of the projectile launching device are further based on the determined correction pan and correction tilt angles.

9. The method of any preceding claim wherein: the propelled projectile is a tracing projectile; and the first data and / or second data comprises information about a trace of the propelled projectile.

10. The method of any preceding claim, wherein: the first and / or second passive sensors comprise an electrooptical sensor; and the first data and / or second data includes one or more images.

11. The method of the preceding claim, wherein determining the position of the target comprises determining a type of the target, in particular a physical size of the target; and calculating the desired trajectory and / or a distance between the passive sensor and the target based on the type, in particular the physical size, of the target.

12. The method of any of claims 9-11, wherein determining a location of the propelled projectile based on the first data comprises: detecting points in the first data with brightness values that exceed a predetermined threshold, and determining the location based on the detected points, the method preferably comprising: applying a threshold to the colours and brightness values of the one or more images of the first data; optionally applying an extreme darker colour or an extreme brighter colour to all areas of the image with colour and brightness values that are below the applied threshold; detecting the points in the image; determining the location of the propelled projectile based in the detected points.

13. The method of any preceding claim, wherein the target is an unmanned aerial vehicle, such as a drone.

14. A system comprising one or more processors and one or more storage devices, wherein the system is configured to perform the computer-implemented method of any preceding claim.

15. A computer program product for loading into a memory of a computer, comprising instructions, that, when executed by a processor of the computer, cause the computer to execute a computer-implemented method of any of claims 1-13.

Images