Abstract: A remote weapon control device for controlling a weapon having a photographing device is provided. The remote weapon control device includes: a communication interface configured to receive an image captured by the photographing device; an object extractor configured to extract objects from the image; a target extractor configured to extract targets from the objects; a shooting order determinator configured to determine an order of the targets for shooting; and a control signal generator configured to generate a shooting control signal for controlling the weapon to shoot the targets in the determined order.

Abstract: A system including one or more processors and one or more non-transitory computer-readable media storing computing instructions configured to run on the one or more processors and perform: obtaining an image of an item; removing background pixels from the image by removing white pixels from the image up to a first threshold; determining an item outline of the item in the image, wherein the item outline comprises aliased pixels along a periphery of the item in the image; removing grey pixels from the item outline in the image up to a second threshold to create a first updated image; removing shadows from the first updated image to create a second updated image based on a saliency map and a third threshold for shadow-like grey pixels; mapping each pixel in the second updated image to a respective mapped color in a predetermined color palette; and determining one or more dominant colors of the respective mapped colors based on one or more highest respective percentages of the respective mapped colors.

Abstract: A system for radar interference mitigation, preferably including one or more transmitter arrays, receiver arrays, and/or signal processors, and optionally including one or more velocity sensing modules. A method for radar interference mitigation, preferably including transmitting a set of probe signals, receiving a set of reflected probe signals, and/or evaluating interference, and optionally including decoding the set of received probe signals and/or compensating for interference.

Abstract: While a radar waveform generator coupled to a phased antenna array is inactive, a beam steering command is provided to the phased antenna array to cause the phased antenna array be configured for a given transmit and receive direction. While the radar waveform generator is active, received radar results are assigned to the given transmit and receive direction. the providing of the command and the assigning are repeated for a plurality of additional transmit and receive directions corresponding to a desired scan area.

Abstract: A level measurement instrument comprises an analog circuit for transmitting a pulse signal at a target of interest and receiving reflected echoes of the pulse signal and developing an echo waveform representative of the reflected echoes. A programmed digital circuit is operatively coupled to the analog circuit and comprises a programmed controller and memory. The controller is operatively programmed to identify peaks in the echo waveform and store an active peak list in the memory from a current measurement scan and a buffer peak list from prior measurement scans. The controller is further programmed to match peaks in the active peak list to peaks in the buffer peak list, to select a target peak from the active peak list based on which of the matched peaks have moved, and determining material level responsive to the target peak.

Abstract: A method of targeting a missile. A plurality of images of a target, taken from a plurality of viewpoints, are received. Features in the images characteristic of the target are identified. Data representing the characteristic features are provided to the missile to enable the missile to identify, using the characteristic features, the target in images of the environment of the missile obtained from an imager included in the missile.

Abstract: The invention relates to a method for deflecting space debris comprising steps of: launching (E2) a thruster (2) by means of a sounding rocket (1) at a target altitude close to that of the one or more debris to be deflected. generating (E3) by the thruster a gas cloud (G) above the sounding rocket.

Abstract: Methods, systems and apparatuses for selecting parameters of a beam are disclosed. One method includes selecting, by a network controller of a wireless network, coarse beam parameters of each of a plurality of antenna arrays of a first node or a second node of the wireless network based on one or more static parameters of the first node and the second node, selecting, by at least one of the first node or the second node of the wireless network, fine beam parameters of each of the plurality of antenna arrays of the first node or the second node based on perturbations to dynamic parameters of at least one wireless link between the first node and the second node, and forming at least one beam by at least one of the first node or the second node using the coarse beam parameters and the fine beam parameters.

Abstract: A method for calibrating a three dimensional time-of-flight camera system mounted on a device, includes determining at a first instant a direction vector relating to an object; determining an expected direction vector and expected angle for the object to be measured at a second instant with reference to the device's assumed trajectory and optical axis of the camera; determining a current direction vector and current angle at the second instant; determining an error represented by a difference between the current direction vector and the expected direction vector; and using the error to correct the assumed direction of the main optical axis of the camera system such that said error is substantially eliminated.

Abstract: An information processing apparatus comprises: a registration unit adapted to register information required to determine at least one specific pattern in an image; an input unit adapted to input image data; a first generation unit adapted to extract a predetermined feature distribution from the input image data, and to generate a first feature distribution map indicating the feature distribution; a second generation unit adapted to generate a second feature distribution map by applying a conversion required to relax localities of the first feature distribution map to the first feature distribution map; and a determination unit adapted to determine, using sampling data on the second feature distribution map and the registered information, which of the specific patterns the image data matches.

Abstract: Systems and methods for improving vehicle survivability. In some embodiments, threat information relating to at least one potential threat against at least one vehicle during a mission may be accessed. The threat information may comprise threat location information indicative of at least one likely location for the at least one potential threat and at least one model associated with the at least one potential threat. Prior to commencing the mission, the threat information may be used to assign a numerical measure to each potential action of a plurality of potential actions for the at least one vehicle based at least in part on at least one measure of the at least one vehicle resulting from executing the potential action. The plurality of potential actions may be compared based at least in part on the respective numerical measures assigned to the plurality of potential actions.

Abstract: The present invention relates to a method of scheduling for multi-function radars. Specifically, the present invention relates to an efficient urgency-based scheduling method. The present invention provides a method of scheduling tasks in a radar apparatus including the steps of: receiving one or more tasks to schedule; calculating an urgency function for each said task; and storing the said tasks using said urgency function to order each said task relative to the other said tasks; wherein when a task is to be performed, the task having the highest value of urgency function is located.

Abstract: System and methods for managing targets of a vehicle is provided. In some aspects, a system may include a boundary check module configured to receive boundary information from a flight safety system. The boundary information comprises a selected termination boundary of a plurality of termination boundaries confining navigation of the vehicle. Each of the plurality of termination boundaries is associated with a target of a plurality of targets of the vehicle. The system may further include a target modification module configured to select the target associated with the selected termination boundary, and a target guidance module configured to provide the selected target to a guidance and control system of the vehicle.

Abstract: A missile includes a radar system that has a radome through which a main antenna sends and receives signals. The radome includes a radome body and a radome tip include different transmissive materials, with for example the radome body primarily made of a lossy optically nontransparent material, and the radome tip primarily made of a lossless (permittivity with low imaginary part) glass material that may also be optically transparent. A laser may be used in conjunction with the radome to send and receive encoded signals. The laser may be located behind (aft of) the main antenna, and one or more optical fibers may extend into and/or along the radome to guide laser signals to the radome tip. The laser may be used to emit encoded signals so as to allow multiple radar systems operating in the same area at the same time to discriminate between different targets.

Abstract: A ranging seeker apparatus includes an RF antenna and a bistatic ranging detector operatively connected with the RF antenna. The RF antenna and bistatic ranging detector are operative for detecting one or more guidance objects in a RF band and providing angle and range data to the missile. Also, a missile including a missile body, a missile propulsion system disposed in or on the missile body, and the ranging bistatic RF seeker disposed in or on the missile body.

Abstract: In certain aspects, this invention is a “control system” that detects and minimizes (or otherwise optimizes) an angle between vehicle centerline (or other reference axis) and vehicle velocity vector—as for JDAM penetration. Preferably detection is exclusively by optical flow (which herein encompasses sonic and other imaging), without data influence by navigation. In other aspects, the invention is a “guidance system”, with optical-flow subsystem to detect an angle between the vehicle velocity vector and line of sight to a destination—either a desired or an undesired destination. Here, vehicle trajectory is adjusted in response to detected angle, for optimum angle, e.g. to either home in on a desired destination or avoid an undesired destination (or rendezvous), and follow a path that's ideal for the particular mission—preferably by controlling an autopilot or applying information from navigation.

Abstract: A technique for suppressing backwaves employs a photonic approach. In one aspect, the technique includes an apparatus, including: a radiating element; and a microwave-photonic device for suppressing backwaves from the radiating element. In a second aspect, the technique includes a method for removing unwanted radiation from a radiating device, comprising: receiving unwanted radiation from the radiating device; communicating the received radiation to an electro-optically active material; communicating laser light to the electro-optically active material; communicating electromagnetic products of interactions between the radiation and the laser light to a photodiode; and communicating photodiode outputs to a termination.

Abstract: Disclosed are a method and system for improving real-time determination of flight parameters of an aircraft during flight. A selection module selects and delivers measured values of input parameters to an estimation unit, and the estimation unit uses the input parameters to estimate at least two selected flight parameters. The input parameters are received by the estimation unit on the basis of identified flight mechanics equations associated with the selected flight parameters. The estimation unit includes an extended Kalman filter, which is configured to receive the values of the input parameters and to output joint estimations of the selected flight parameters based on the flight mechanics equations, during the flight of the aircraft.

Abstract: A miniature lightweight high-maneuverability missile (10) has a missile body (12) with three sets of at least two aerodynamic control surfaces (14, 16, 18) for independent control of roll, pitch and yaw of the missile. Each set of control surfaces (14, 16, 18) is independently controlled by a corresponding actuator (20) deployed within the missile body (12). Other preferred features include selection of an elevation angle of incidence at a target, and switching between explosive and kinetic modes of operation.

Abstract: A method for determining a position of a device in a reference coordinate system. The method including: receiving, at the device, less than all of GPS signals necessary to determine the position of the device in the reference coordinate system; transmitting a signal from a? illuminating source defined in the reference coordinate system; receiving the signal at a cavity waveguide disposed on the device; and determining the position of the device in the reference coordinate system based on the GPS signals and the signal received in the cavity waveguide. The signal received in the cavity waveguide can also be used to confirm a position determined by the GPS signals.

Abstract: A system for engaging hostile air or space threats with a defensive missile, where the defensive missile comprises an antenna for receiving global positioning system (GPS) signals. A global positioning system receiver is coupled to said antenna, for receiving global positioning system signals directly from global positioning system satellites and global positioning system signals reflected from the threat. A processing arrangement processes the direct and reflected global positioning system signals for determining the position and velocity of the threat. Vectoring controls are coupled to the processing arrangement, and are responsive to the location of the threat for directing the defensive missile toward the threat. In a particular embodiment, the antenna of the defensive missile is directionally controllable, and the defensive missile includes an antenna direction controller responsive to the processor for directing at least a beam of the antenna toward the threat.

Abstract: A sensor system uses ground emitters to illuminate a projectile in flight with a polarized RF beam. By monitoring the polarization modulation of RF signals received from antenna elements mounted on the projectile, both angular orientation and angular rate signals can be derived and used in the inertial solution in place of the gyroscope. Depending on the spacing and positional accuracies of the RF ground emitters, position information of the projectile may also be derived, which eliminates the need for accelerometers. When RF signals of ground emitter/s are blocked from the guided projectile, the sensor deploys another plurality of RF antennas mounted on the projectile nose to determine position and velocity vectors and orientation of incoming targets.

Abstract: A method for onboard determination of a roll angle of a projectile. The method including: transmitting a polarized RF signal from a reference source, with a predetermined polarization plane; receiving the signal at a pair of polarized RF sensor cavities positioned symmetrical on the projectile with respect to a reference roll position on the projectile; measuring a difference between an output of the pair of polarized RF sensor cavities resulting from the received signal to determine zero output roll positions of the projectile; and comparing an output of the pair of polarized RF sensor cavities at each of the zero output positions to determine when the projectile is parallel to the predetermined polarization plane. The method can also include analyzing an output of at least one third sensor positioned on the projectile to determine whether the roll angle position of the projectile is up as compared to the horizon.

Abstract: Embodiments of a guidance section that compensates for boresight error (BSE) caused by effects of a composite radome. The guidance section includes a BSE compensation element to add high-pass filtered noise to compensated BSE data. The guidance section also includes and a Kalman filter to generate line-of-sight rate (LOSR) BSE noise from the compensated BSE data and the added high-pass filtered noise. In some embodiments, a method for generating a revised BSE correction matrix is provided. The revised BSE correction matrix may compensate for BSE caused by effects in the composite radome and may correct for relative target velocity error.

Abstract: A method for determining a target angle. Optical frequency or radio frequency energy is received through a pair of fixed, foreshortened, and opposing subwavelength apertures in a lensing system. A lens of the lensing system positions at least one of the pair of fixed, foreshortened, and opposing subwavelength apertures and includes a dielectric medium, and a substrate encased in the dielectric medium and defining at least one of the pair of fixed, foreshortened, and opposing subwavelength apertures. A target angle is determined from a steep change of amplitude versus angle presented by the pair of fixed, foreshortened, and opposing subwavelength aperture's beamwidth from the received optical frequency or radio frequency energy.

Abstract: A molded dichroic mirror and a seeker comprising a molded dichroic mirror are provided. The dichroic mirror may be molded from polysiloxane or lithia potash borosilicate and may be coated to reflect an infrared signal and configured to transmit a radio frequency signal between 33 GHz and 37 GHz.

Abstract: A vehicle including electro-optic (EO) imaging has a vehicle body having an outer surface including a front portion and a side portion, wherein the side portion includes a plurality of portholes. A propulsion source is within the vehicle body for moving the vehicle. A fixed EO imaging system having a field-of-regard (FOR) includes a plurality of fixed EO imaging sub-systems arrayed within the vehicle body. The fixed EO imaging sub-systems each have a different field-of-view (FOV) for providing a portion of the FOR and include a camera affixed within the vehicle body and an optical window secured to one of the portholes for transmitting electromagnetic radiation received from one of the portions of the FOR to the camera, wherein the cameras each generate image data representing one of the portions of the FOR therefrom. A processor is coupled to receive the image data from the plurality of fixed EO imaging sub-systems for combining the image data to provide composite image data spanning the FOR.

Abstract: A SAR image recorded by a reconnaissance system is transferred as a reference edge image together with the data of the trajectory as a reference. The signal of the infrared seeker head of the missile is converted into a virtual SAR edge image and compared to the SAR reference image to calculate the precise position of the missile.

Abstract: Method and control system for providing control commands for a vehicle steerable by an operating unit or for an image acquisition device of the vehicle by sequential display of acquired image data on an image display device of the operating unit connected to the vehicle via a data transfer connection. The method includes acquiring data of an image recorded by the image acquisition device, acquiring vehicle state data at a time the image was recorded, and compressing the image data. The method also includes transferring the compressed image data and the vehicle state data via the data transfer connection to the operating unit, decompressing the transferred image data to form a displayable image, and displaying the displayable image on the image display device.

Abstract: Embodiments of a guided munition are provided, as are embodiments of a method for equipping a guided munition with an interlocking dome cover. In one embodiment, the guided munition includes a munition body, a seeker dome coupled to the munition body, and an interlocking dome cover. The interlocking dome cover includes a plurality of detachable dome cover sections collectively enclosing the seeker dome and a dome cover deployment device coupled to the plurality of detachable dome cover sections. When actuated, the dome cover deployment device initiates separation of the plurality of detachable dome cover sections to expose the seeker dome.

Abstract: Guided airborne weapons fired in a salvo against multiple targets are deconflicted by performing a scene correlation of multiple cued targets to TLOs acquired by the seeker's imaging sensor to track a target package. If the weapon is provided with a multimode seeker, target cues for a common designated target and a common SAL code are provided to each weapon. Each weapon uses its SAL sensor to detect and process a SAL return to verify the common SAL code and augment their scene correlations by fixing the TLO track file of the common designated target to the cued track file associated with the designated target. At terminal, each weapon commits to a particular target by referencing its assigned target to the tracked target package. Correlation to multiple targets in the target package makes the acquisition and tracking process more robust and reduces targeting ambiguity. Furthermore, a single SAL designation can improve the tracking of all the weapons to their respective targets.

Abstract: Virtual Aperture Radar (VAR) imaging provides terminal phase radar imaging for an airborne weapon that can resolve multiple closely-spaced or highly correlated scatterers on a given target with a single pulse to provide an aimpoint update at a useful range to target without training data and without requiring a large aperture antenna. VAR imaging exploits the sparse, dominant-scatterer nature of man-made targets. The array manifold is constructed with a large number of basis functions that are parameterized by range or angle (or both) to target. The number of basis functions extends the capability to resolve scatterers beyond the Rayleigh resolution. However, this also makes the manifold underdetermined. A sparse reconstruction technique that places a sparsity constraint on the number of scatterers is used to solve the manifold to uniquely identify the ranges or angles to the scatterers on the target.

Abstract: In a CLOS missile guidance system, target and missile tracking data e.g. video image data are acquired on a UAV and transmitted to the missile where they are processed to provide guidance control data to the missile. Alternatively the video image data may be transmitted to a command station where the guidance control data is generated and transmitted to the missile, preferably via the UAV.

Abstract: A method including detecting a threat incoming to a vehicle, the vehicle having a plurality of countermeasures including a primary armament and an active protection system, communicating the detected threat to a controller, activating, with the controller, a first sensor in response to the detecting, the first sensor tracking the incoming threat and generating tracking data, routing, with the controller, the tracking data to a plurality of fire control processors, each of the plurality of fire control processors being associated with a respective one of the plurality of countermeasures, and the plurality of fire control processors simultaneously computing respective firing solutions using the tracking data, and determining, with the controller, a preferred countermeasure out of the plurality of countermeasures with which to counter the incoming threat.

Abstract: A method for determining a location of a flying target included identifying and measuring the target by at least two seeker systems disposed at a distance from one another. The position of the target relative to at least one of the two seeker systems is determined from measurement data derived therefrom. The position of the target is measured inconspicuously and without active radiation, in that the seeker systems are data-networked, passive target tracking systems for missiles, which autonomously track the target and align the missile with the target. The measurement data determined by the data-networked seeker systems are combined, and the location of the target is determined from the combined data.

Abstract: A missile radar system includes a tapered radome covering a front face of a main antenna. A calibration antenna is the combination of a metal tip and an attached one or more radiating or excitation elements (monopole) on the tip. A narrow end (wedge) of the radome may aid in directing planar calibration waves toward the main antenna. The metal tip has a curved inner surface that acts, with the attached radiating element(s), as an aperture antenna. Signals are emitted from the calibration antenna back toward the front face of the main antenna. The signals pass from the tip/reflector to the front face of the main antenna through a substantially-metal-free and substantially-dielectric-free volume defined by the inner surface of the radome. The radar system allows for calibration of the antenna prior to launch and/or during flight of the missile.

Abstract: A hostile missile is identified as being of a type which maneuvers aerodynamically within the atmosphere when it performs an exoatmospheric maneuver which significantly changes its specific energy. When the determination is made that the hostile missile is an atmospheric maneuvering missile, the hostile missile is engaged with an interceptor which is guided toward a predicted intercept point (PIP) assuming horizontal hostile missile flight at an altitude above a specified minimum altitude.

Abstract: In various aspects and embodiments, incident electromagnetic radiation is received through a subwavelength aperture in a lens, the subwavelength aperture being defined by a substrate encased in a dielectric medium.

Abstract: A number of apparatuses are provided, for sensing and/or emitting energy along one or more desired apparatus line of sights (LOS) with respect to the respective apparatus. In at least one embodiment, the apparatus includes an assembly that is rotatably mounted on a base with respect to a switching axis. The assembly has two or more sensing/emitting units, each having a respective sensing/emitting unit line of sight (ULOS). Each sensing/emitting unit has an operative state, wherein the respective unit ULOS is pointed along a LOS of the apparatus for sensing and/or emitting energy along the LOS, and a corresponding inoperative state, where the respective unit ULOS is pointed along a direction different from this LOS. A switching mechanism enables switching between the sensing/emitting units to selectively bring a desired sensing/emitting unit exclusively into its respective operative state while concurrently bringing a remainder of the sensing/emitting units each to a respective non-operative state.

Abstract: In order to target and intercept a desired object within a number of objects detected in an environment, detection data is received from two different sensors, where the detection data includes spatial coordinates. A set of four-point subsets (tetrahedra) are selected from each set of spatial coordinates. A number of correlation maps are determined between the first set of spatial coordinates and the second set of spatial coordinates based on the plurality of four-point subsets. The mean sphericity for each corresponding plurality of four-point subsets in the plurality of correlation maps is determined, and a threat object map based on the correlation map having the greatest mean sphericity is created. The desired object is targeted based on the correlation map.

Abstract: Virtual Aperture Radar (VAR) imaging provides terminal phase radar imaging for an airborne weapon that can resolve multiple closely-spaced or highly correlated scatterers on a given target with a single pulse to provide an aimpoint update at a useful range to target without training data and without requiring a large aperture antenna. VAR imaging exploits the sparse, dominant-scatterer nature of man-made targets. The array manifold is constructed with a large number of basis functions that are parameterized by range or angle (or both) to target. The number of basis functions extends the capability to resolve scatterers beyond the Rayleigh resolution. However, this also makes the manifold underdetermined. A sparse reconstruction technique that places a sparsity constraint on the number of scatterers is used to solve the manifold to uniquely identify the ranges or angles to the scatterers on the target.

Abstract: A method for commanding an attitude change of a boosting missile to tend to maintain good communication link quality includes the step of precalculating attenuation of a link between the boosting missile and a ground station in the presence and absence of multiple missile plumes. If the actual link attenuation is less than the precalculated attenuation in the absence of multiple missile plumes, no attitude change is commanded. If the actual link attenuation exceeds the precalculated value, the actual link attenuation is compared with the calculated attenuation in the presence of multiple missile plumes. If the calculated multiple plume RF attenuation is less than the actual link attenuation, the attenuation is deemed to be caused by some factor other than multiple plume attenuation, and produces a flag for commanding a change in attitude.

Abstract: A method for engaging a target missile includes sensing the position of the target and of an interceptor missile, and determining time-to-go to intercept and direction of thrust of the interceptor. A one-step intercept solution is determined based on position estimates of the target and the interceptor and is used to iteratively estimate at least two components of a three-dimensional unit thrust vector, and apply updated guidance commands to the interceptor. A system for thrust vector control of an interceptor against a target missile includes a processor for receiving sensed target signals, determining a one-step initial solution to produce time-to-go and current direction of thrust of the interceptor, iteratively estimating at least two components of a three-dimensional unit thrust vector, and producing a guidance vector for application to the interceptor.

Abstract: Methods, apparatus, and computer readable media for designing an effective and efficient directed energy weapon system. A method for designing a directed energy weapons system may include modeling an environment and postulating a directed energy weapons system deployment. The capability of the postulated directed energy weapon system deployment to defend a target aircraft against a missile threat within the environment may then be simulated. The postulated directed energy weapon system deployment may be iteratively improved based on simulation results.

Abstract: A missile includes a radar system that has a radome through which a main antenna sends and receives signals. The radome includes a radome body and a radome tip include different transmissive materials, with for example the radome body primarily made of a lossy optically nontransparent material, and the radome tip primarily made of a lossless (permittivity with low imaginary part) glass material that may also be optically transparent. A laser may be used in conjunction with the radome to send and receive encoded signals. The laser may be located behind (aft of) the main antenna, and one or more optical fibers may extend into and/or along the radome to guide laser signals to the radome tip. The laser may be used to emit encoded signals so as to allow multiple radar systems operating in the same area at the same time to discriminate between different targets.

Abstract: A missile radar system includes a tapered radome covering a front face of a main antenna. A calibration antenna is the combination of a metal tip and an attached one or more radiating or excitation elements (monopole) on the tip. A narrow end (wedge) of the radome may aid in directing planar calibration waves toward the main antenna. The metal tip has a curved inner surface that acts, with the attached radiating element(s), as an aperture antenna. Signals are emitted from the calibration antenna back toward the front face of the main antenna. The signals pass from the tip/reflector to the front face of the main antenna through a substantially-metal-free and substantially-dielectric-free volume defined by the inner surface of the radome. The radar system allows for calibration of the antenna prior to launch and/or during flight of the missile.

Abstract: A laser energy detector may include at least one photodetector device formed on a semiconductor substrate. The photodetector device may have an active area effective to detect laser energy at a laser wavelength. The active area of the laser energy detector may be substantially transparent for a first wavelength band within an infrared portion of the electromagnetic spectrum.

Abstract: The disclosed approach provides a low-cost approach by employing a single channel receiver for a direction-finding missile, rather than a conventional four-channel system. It employs interferometry techniques. The proposed approach leverages orthogonal waveforms and pseudorandom noise (PN) codes. This is a low-cost approach for a single channel direction finding system by leveraging orthogonal waveforms and interferometric techniques.

Abstract: A method for onboard determination of a roll angle of a projectile. The method including: transmitting a polarized RF signal from a reference source, with a predetermined polarization plane; receiving the signal at a pair of polarized RF sensor cavities positioned symmetrical on the projectile with respect to a reference roll position on the projectile; measuring a difference between an output of the pair of polarized RF sensor cavities resulting from the received signal to determine zero output roll positions of the projectile; and comparing an output of the pair of polarized RF sensor cavities at each of the zero output positions to determine when the projectile is parallel to the predetermined polarization plane. The method can also include analyzing an output of at least one third sensor positioned on the projectile to determine whether the roll angle position of the projectile is up as compared to the horizon.

Abstract: A method for onboard determination of a roll angle of a projectile.