Abstract: A foregrip for use with a firearm having a handguard mounting platform. The foregrip comprises a unitary body attachable to a handguard and configured with a front end, an intermediate section and a rear end. A front end designed to form a vertical engagement portion, an intermediate section designed to be partially curved engagement section and extending from the front end to the rear end, and a rear end designed to form a top portion and a lower portion. The top portion forming a first angled engagement portion, and the lower forming a second angled engagement portion. An attachment surface provides a method for mounting the foregrip onto a firearm handguard.

Abstract: A handguard comprising a plurality of layers of composite material. At least one of the layers is a ceramic matrix composite and at least one of the layers, and preferably the outer later, is a carbon fiber reinforced composite. In addition, the outermost layer is preferably a woven fabric carbon fiber reinforced composite. In one embodiment, one or more ceramic matrix composite layers is sandwiched between layers of carbon fiber reinforced composite. In another embodiment, an innermost layer is a ceramic matrix composite and the outermost layer is a carbon fiber reinforced composite.

Abstract: A portable gun carrying case with standard foam inserts that has legs hidden inside under the foam. After the gun/rifle is removed, the legs are pinned into place using the supplied pins. Once the legs are pinned into place the case/table is turned over onto the legs making it a table to be used for a shooting bench/table/rest.

Abstract: A sight includes an adjusting module, a collector ring, a first adjusting element, and an elastic element. The collector ring includes a connecting end connected to the adjusting module, a free end opposite to the connecting end, a periphery connecting the connecting end and the free end, and a notch formed on the periphery and connected to the free end. The first adjusting element includes a first end which abuts the periphery. The elastic element extends in a direction from the free end to the connecting end and abuts the periphery. The elastic element contacts the periphery in a position between the notch and the connecting end. The first end is configured to resist an elastic force exerted by the elastic element and move the collector ring.

Abstract: An optical positioning aiming system including an optical positioning subsystem (subsystem). The subsystem is configured to determine relative positions of a weapon and a head mounted display. The subsystem includes a processing unit, infrared (IR) emitters mounted to a weapon, IR emitters mounted to the head mounted display, IR cameras mounted to the weapon, and IR cameras mounted to the head mounted display. The IR cameras mounted to the weapon are configured to determine a relative position of the IR emitters mounted on the head mounted display and to communicate the relative position of the IR emitters mounted on the head mounted display to the processing unit. The IR cameras mounted to the head mounted display are configured to determine a relative position of the IR emitters mounted to the weapon and communicate the relative position of the IR emitters mounted to the weapon to the processing unit.

Abstract: This disclosure describes a compact and lightweight rifle scope display adapter configured to be affixed in front of the objective lens of a rifle scope. The display adapter includes a receptacle that enables the adapter to be electrically connected to a ballistic computer, rangefinder or other targeting mechanism. The display adapter is configured to receive aimpoint information and project illuminated symbology that is brought into focus by the rifle scope optics in such a way that the symbology appears to overlay an image of a scene on which the rifle scope is focused. The display adapter includes a casing that houses processing circuitry, a light emitting diode, polarizer, polarized beam splitter, liquid crystal on silicon imaging element and reflective element. The display adapter also includes a light bar, spherical mirror, quarter-wave plate and an additional polarized beam splitter contained within the light bar.

Abstract: A system for recording gun activity that includes: a mounting bracket; a camera, where camera is attached the mounting bracket and the mounting bracket enables attachment to a gun barrel; a camera lens directed inline with the gun barrel; a lighting mechanism within the camera directed in the line of sight of the camera lens; a microprocessor incorporated into the camera; a battery, where the battery supplies power to the camera; a memory chip, where the memory chip stores images captured by the camera; and a proximity sensor, where the proximity sensor activates the camera lens and lighting mechanism and places the camera in a record mode. The camera may further include a USB port for transmitting data to and from the camera. Preferably, the system also includes a holster, where the holster includes an external battery. The camera may further include charging strips where the charging strips connect to the external battery of the holster.

Abstract: A shock attenuation system configured to reduce shock experienced by an optical device coupled to a weapon includes an inner rail support configured to couple to the weapon and at least two outer rail supports substantially parallel to the inner rail support. The at least two outer rail supports are configured to couple to the optical device. The shock attenuation system also includes a first spring feature coupled to a first of the at least two outer rail supports and the inner rail support, and a second spring feature coupled to a second of the at least two outer rail supports and the inner rail support. The shock attenuation system further includes a viscoelastic material coupled to at least one of: the inner rail support, the first outer rail support, the second outer rail support, the first spring feature, or the second spring feature.

Abstract: A pressure impulse mitigating barrier comprising a cross-linked gel comprising water and gelatin which has been crosslinked using (I) a functional silane compound comprising an electrophilic group (which is not a silane) and a group of formula (A) where R is H, a C1-10 alkyl group, C6-10 aryl group, or C7-12 arylalkyl group; R? is C1-10 alkyl group or C6-10 aryl group, or C7-12 arylalkyl group; n is 0-2, with the proviso that at least one R is not H; said functional silane having an Mw of 800 g/mol or less; (II) a transition metal, lanthanide or Al compound; or (III) an enzyme such as transglutaminase.

Abstract: The invention relates to ballistic resistant article having a multilayered material sheet which includes a consolidated stack of unidirectional monolayers of drawn polymer, whereby the draw direction of two subsequent monolayers in the stack differs. At least one monolayer comprises a plurality of unidirectional tapes of the drawn polymer, aligned in the same direction, whereby adjacent tapes do not overlap. The invention also relates to a process for the preparation of the multilayered material sheet, and to a ballistic resistant article comprising the multilayered material sheet.

Abstract: A shield cover and a shield retaining such a cover with an electrical discharge system with an activated condition wherein electrical power is applied to an electrically conductive pathway, which can be formed from positive and negative electrical pathways running generally parallel, on the shield cover. The shield cover has a shield cover body for being applied to, retained by, and removed from the shield body. An electrical discharge system is formed by a source of electrical power, the electrically conductive pathway, and a switch or other actuator for activating the electrical discharge system to the activated condition. The shield cover body could be formed from a stretch fabric, and the electrically conductive pathway could be formed by conductive thread. Electrical insulation material can prevent arcing between the shield cover and the shield body. An arcing structure can automatically or selectively produce visible or audible electrical arcing.

Abstract: A network connection framework for connecting a dartboard to a portable device includes: a cloud server; a communication device communicating with the cloud server via a communication network; a dartboard including a dartboard unit, a sensing unit and a dartboard wireless communication unit which connects the dartboard to the cloud server via wireless signal, the dartboard wireless communication unit serves to receive and transmit the score signal to the could server; and a portable device with a portable device wireless communication device which connects the portable device to the cloud server via wireless signal. When the user registration information is inputted in the portable device, the score corresponding to the score signal will be displayed. Therefore, the dart game can be played by players in different venues, and consequently is not restricted by the number of the players and the size and location of the venue.

Abstract: Disclosed is a dart game apparatus providing a dart game match-up mode. The dart game apparatus may include: a control module providing a dart game match-up mode among a plurality of teams each constituted by one or more players; and a display module outputting a dart game image in the dart game match-up mode.

Abstract: A projectile includes a body preferably in the shape of a bullet and having a density less than the density of lead. The projectile further includes a stabilizer adhered to the body. The stabilizer is configured to engage rifling of a barrel of a firearm and impart rotation to the projectile as the projectile travels through the barrel. A preferred ammunition cartridge includes a primer, a propellant, and the aforesaid projectile, as well as a casing containing the primer, propellant and projectile, with the projectile projecting from the casing. Other projectiles in accordance with aspects and features of the invention further are disclosed.

Abstract: An improved bullet disclosed includes a blend radius disposed between a first tangent thereof intersecting a shank of the bullet and a second tangent thereof intersecting one of a cone ogive and a boattail ogive of the bullet. The bullet also includes at least one dimple formed into a base of the bullet adjacent the boattail ogive, a curved segment joining the dimpled base and the boattail cone and a truncated cone ogive with a meplat end and a shank end, the truncated cone ogive adapted to produce less drag and friction in air than a secant or a tangent ogive. The improved bullet extends an effective flight range and a Coanda effect there around reducing air turbulence and drag on the bullet in flight. A cartridge adapted to receive the improved bullet is necked down and shortened for a COAL (cartridge overall length) nominally the same as conventional cartridges.

Abstract: Improvements in a reusable polyurethane projectile are presented. The reusable polyurethane projectile performs like a bullet or projectile because the projectile is essentially the same size and shape of a bullet and can be fed through a normal bullet clip into the breach of a gun, fired and ejected. The reusable polyurethane projectile conforms to the rifling of the barrel of the firearm to spin the projectile and provide equivalent accuracy to a metallic bullet. Upon impact the projectile will flatten and then rebound to the original shape. Standard re-loading mechanisms can be used to install the projectile back into a prepared cartridge. The reusable projectile is fabricated from a casting process that increases the resistance of the polyurethane from melting when the hot gun gunpowder pushes the reusable projectile out of the barrel of the gun.

Abstract: A tape measure includes a spool, a housing defining an opening, where the spool is rotatably coupled to the housing, and a blade including a first end and a second end, where the first end is connected to the spool and the second end is movable through the opening between a retracted position and an extended position. The manually retractable tape measure further includes a cleaning assembly positioned within the housing adjacent the opening such that the cleaning assembly is in contact with the blade to push away debris from the blade as the blade moves between the retracted position and the extended position.

Abstract: A plate flatness measurement device, including a support frame including a center area, the center area including a through-hole in a center of the center area, and a peripheral area surrounding the center area, the peripheral area having a plate with protrusions on a bottom surface of the plate mounted to the peripheral area; and a sensor module in the support frame, the sensor module at least partially protruding above the support frame to contact the protrusions.

Abstract: A tilt angle adjuster includes a base plate attached to a Z slider; a hanging plate attached to a measuring device main body; a thin coupling plate supporting the hanging plate such that the hanging plate is suspended on a first surface side of the base plate; biasers biasing the hanging plate so as to impart a rotational force in a first direction to the hanging plate; and a micrometer head provided so as to push the hanging plate one of directly and indirectly toward a second direction opposite the direction of the rotational force imparted by the biasers.

Abstract: In some aspects, a wireless system is configured for estimating a thickness of a material layer on a surface of an aircraft. The wireless system includes a tag device located beneath a material layer. The tag device is capable of transmitting an electromagnetic signal in response to an electromagnetic signal. In some aspects, a transceiver device is configured to estimate the thickness of a material layer on a surface of an aircraft. The transceiver can be configured to communicate with a tag using electromagnetic signals. The transceiver can include one or more processors configured to measure signal strength and correlate the signal strength to the thickness of a material layer.

Abstract: A strain sensor and a method of manufacturing the same are provided. The strain sensor includes a substrate, a nanocomposite layer disposed on the substrate, and a protective layer disposed on the nanocomposite layer. The nanocomposite layer includes metallic nanowires, a first polymeric material, and a second polymeric material. The protective layer includes a third polymeric material. The metallic nanowires are randomly arranged in the nanocomposite layer.

Abstract: Printing apparatuses for detection of substrate alignment, methods for manufacture and use thereof, and substrates are disclosed. One printing apparatus may include a printing assembly having at least one conductive alignment sensor with a plurality of inductive coils configured to generate an electromagnetic field. The printing assembly may receive at least one substrate having at least one conductive portion and align the substrate such that the plurality of inductive coils and the conductive portion substantially overlap with each other to form an electromagnetic field having a direction from the at least one conductive alignment sensor to the at least one conductive portion. The direction of the electromagnetic field with respect to the conductive alignment sensor may form an angle. The conductive alignment sensor may be configured to detect a movement of the conductive portion when a change to the angle causes a current change through the plurality of inductive coils.

Abstract: Techniques for extracting phase data of off-axis interferogram images are disclosed. At least one sample-related interferogram image associated with a sample is spectrally decomposed to obtain a set of frequency components thereof, and a portion of the set of frequency components is used to generate at least one complex image having a reduced size being smaller in size than the sample-related interferogram image and being indicative of the phase data of the at least one sample-related interferogram image. The reduced size complex image is then used to generate a phase image of the least one sample-related interferogram image.

Abstract: Disclosed is a method for a phase-insensitive single-sampling point (SSP) data collection system. A rotated 90° infrared (IR) THz signal from a step-tunable IR laser is passed though the fast axis of a 90° polarizing rotator. The polarizing rotator and a second IR signal are coupled to free space through an electro-optic phase modulator (EO-PM), where the EO-PM only retards the phase of along the slow-axis. The polarization angle is rotated by 45° to form a beat frequency in each arm. The light is passed through a polarizer aligned with the slow axis of the PM fiber. Lastly, a resultant IR beat signal is fiber coupled back into the system and an erbium doped fiber amplifier (EDFA) in each arm amplifies the IR power prior to pump the THz emitter and detector.

Abstract: The invention relates to applications of optical interference. It is already known to reduce speckle contrast by introducing arbitrary phase shifts in the reference light beam. According to the invention, such phase shifts are not introduced arbitrarily, but systematically whereby the phase changes are synchronised with the acquisition time intervals in such a way that interference fringes can be washed out in selected regions of the beam diameter maintaining high contrast of interference fringes in the desired regions at the same time. This technique can be used for enhancing the lateral resolution in imaging techniques and the bandwidth in optical communications.

Abstract: The present invention relates to a laser sensor for self-mixing interferometry. The laser sensor comprises at least one semiconductor laser light source emitting laser radiation and at least one photodetector (6) monitoring the laser radiation of the laser light source. The laser light source is a VECSEL having a gain medium (3) arranged in a layer structure (15) on a front side of a first end mirror (4), said first end mirror (4) forming an external cavity with an external second end mirror (5). The proposed laser sensor provides an increased detection range and can be manufactured in a low-cost production process.

Abstract: A system that may include a movable support module for supporting an object and a controller, wherein the controller is configured to: receive an estimated location of a movable support module that supports an object and temperature information about an actual or estimated temperature of at least a portion of the object support module; and calculate movable support module location information, in response to (a) the estimated location of the movable support module, (b) the temperature information, and (c) a mapping between (i) values of the temperature information, (ii) estimated locations of the movable support module, and (iii) location errors of the movable support module

Abstract: A dimension detection device includes a first detection unit which is moved to a first predetermined position in a first direction, and configured to detect a current position of the first member, and when the current position of the first member is not a third predetermined position corresponding to the first predetermined position, send a first signal; a second detection unit which is moved to a second predetermined position in the first direction, and configured to detect a current position of the second member, and when the current position of the second member is not a fourth predetermined position corresponding to the second predetermined position, send a second signal; a movement unit which is configured to move the first detection unit and the second detection unit; and an alarm unit configured to send an alarm upon the receipt of the first signal and/or the second signal.

Abstract: Apparatus and method are described for monitoring of coatings deposited on glass articles during a continuous production process. Thus, coating quality is monitored without the need to interrupt the production process by removing an article to another site for analysis. The articles are illuminated and light reflected therefrom is analysed to provide an indication of layer thicknesses within the coating. Colour characteristics may also be reported.

Abstract: The determination of in-plane distortions of a substrate includes measuring one or more out-of-plane distortions of the substrate in an unchucked state, determining an effective film stress of a film on the substrate in the unchucked state based on the measured out-of-plane distortions of the substrate in the unchucked state, determining in-plane distortions of the substrate in a chucked state based on the effective film stress of the film on the substrate in the unchucked state and adjusting at least one of a process tool or an overlay tool based on at least one of the measured out-of-plane distortions or the determined in-plane distortions.

Abstract: An apparatus is described that includes a pixel array having time-of-flight pixels. The apparatus also includes clocking circuitry coupled to the time-of-flight pixels. The clocking circuitry comprises a multiplexer between a multi-phase clock generator and the pixel array to multiplex different phased clock signals to a same time-of-flight pixel. The apparatus also includes an image signal processor to perform distance calculations from streams of signals generated by the pixels at a first rate that is greater than a second rate at which any particular one of the pixels is able to generate signals sufficient to perform a single distance calculation.

Abstract: A method for determining a shape of a substantially cylindrical specular reflective surface includes the step of obtaining calibration data and the step of obtaining target data about a target structure. The method further includes the step of defining a target line from the target data, where the target line represents a feature of the target structure and the step of capturing a reflected image of the target structure in the specular reflective surface. The method further includes the step of obtaining reflected data from the reflected image and the step of defining a reflected line from the reflected data, where the reflected line represents a reflection of the feature of the target structure. The method also includes the step of determining a correspondence between the target line and the reflected line and using the correspondence and the calibration data to determine the shape of the specular reflective surface.

Abstract: A holding apparatus includes, a supporting member having positioning portions for positioning a pattern light generation unit, configured to support the pattern light generation unit, and a fixing member configured to be in contact with an outer circumference of the pattern light generation unit to hold the pattern light generation unit, the fixing member being fixed to the supporting member. The fixing member includes abutting portions configured to be in contact with parts of the outer circumference of the pattern light generation unit, and elastic members configured to press portions of the pattern light generation unit contacting the abutting portions onto the abutting portions.

Abstract: A device and method for estimating the elevation angle of one or more objects surrounding a user terminal include a convex image-reflecting surface, a transparent sighting surface disposed above the convex image-reflecting surface, and an elevation limit marking formed on or in the sighting surface. The elevation limit marking generates a reflected image in the convex image-reflecting surface that defines an elevation angle above a horizon of the earth that the one or more objects in a field of view of the convex image-reflecting surface must remain below so that the user terminal has an unobstructed view of the sky in all azimuthal directions.

Abstract: A system and a method for estimating the elevation angle of one or more objects surrounding a user terminal include a camera device for capturing an image of the sky and a display device for displaying the image of the sky captured by the camera device. One of the camera device and the display device generates an elevation limit marking in the image of the sky displayed by the display device. The elevation limit marking in the image of the sky defines an elevation angle above a horizon of the earth that all the one or more objects in a field of view of the camera device must remain below so that the user terminal has an unobstructed view of the sky in all azimuthal directions.

Abstract: A system for checking the axial position of a bearing (30) inside an hole (31) of an E-block (29), preferably during the assembly of an HSA, comprises a reference system (3) that locates the E-block, a coupling element (17) that comes into contact with the bearing, a floating element (8) that, being connected to the coupling element, assumes the attitude of the bearing, two or more detection devices, for example optoelectronic, that cooperate with the floating element and detect at the same time, at checking areas are spaced apart from each other, quantities indicative of the position and, in case, of the attitude of the bearing with respect to the E-block, and a processing unit (50) for receiving and processing the detected quantities.

Abstract: A metrology performance analysis system includes a metrology tool including one or more detectors and a controller communicatively coupled to the one or more detectors. The controller is configured to receive one or more metrology data sets associated with a metrology target from the metrology tool in which the one or more metrology data sets include one or more measured metrology metrics and the one or more measured metrology metrics indicate deviations from nominal values. The controller is further configured to determine relationships between the deviations from the nominal values and one or more selected semiconductor process variations, and determine one or more root causes of the deviations from the nominal values based on the relationships between values of the one or more metrology metrics and the one or more selected semiconductor process variations.

Abstract: A contact probe includes a stylus, a sensor, and two parallel substantially planar plates. The stylus has a contact. The sensor has a substantially planar shape and includes a fixed portion, at least three thin-walled portions each formed of a planar plate and having a strain sensor vapor-deposited thereon, and a movable portion to which the stylus is mounted and linked to the fixed portion via the thin-walled portions in at least three locations. The two parallel substantially planar plates are connected to the fixed portion on opposing sides and sandwich the movable portion so as to maintain a predetermined distance between the movable portion and the two parallel substantially planar plates and limit movement of the movable portion to a movable range. The sensor outputs a contact signal due to the strain sensors deforming in response to a measurement force from the stylus.

Abstract: A bale measuring method for a rectangular baler having a bale chamber in which bales are formed. The bale measuring method includes steps of measuring a movement of crop material downstream of the bale chamber as the crop material moves backward in the baler, using the measured movement of the crop material downstream of the bale chamber to calibrate a measurement and calculation tool for measuring a movement of crop material in the bale chamber and for calculating a length of a bale being formed in the bale chamber based on the measurement, and determining the length of the bale being formed in the bale chamber using the calibrated measurement and calculation tool as the bale moves backward in the baler.

Abstract: An orientation or position of a device may be determined through a determination of a slope of a path currently being traveled by a vehicle. The slope of the path may be determined from data indicating a movement of the vehicle provided by sensors of a data acquisition device coupled with the vehicle. A tilt value of the data acquisition device using the sensors of the data acquisition device may also be determined. A position of the data acquisition device may be established based on the slope of the path and the tilt value of the data acquisition device.

Abstract: The invention provides an automatic leveling device comprising; one tilt sensor provided on a leveling base plate, a leveling mechanism unit capable of tilting the leveling base plate in at least two directions and a control device for controlling the leveling mechanism unit and for tilting the leveling base plate in a condition as required, wherein the control device is configured so as to tilt the leveling base plate so that a change of the tilting of the leveling base plate follows a searching route as set in a process of a leveling from a condition where a tilt detecting signal from the tilt sensor is not obtained, carries out an auxiliary leveling to obtain signals from the tilt sensor in a process of changing the tilting, and carries out a main leveling by controlling the leveling mechanism unit based on the detection result from the tilt sensor in a case where a tilt detecting signal from the tilt sensor is obtained in a process of the auxiliary leveling.

Abstract: A laser device operating system includes a laser device generating a laser beam when receiving a remote control unit command signal. The remote control unit operates in a public or private mode. In public mode the remote control unit generates a command signal transmitted to the laser device. In private mode the remote control unit generates a unique identifier prepended to the command signal. The laser device operates in a laser device public or private mode. In public mode the laser device responds to the remote control unit command signal or the command signal if transmitted by a second remote control unit. In private mode the laser device operates only upon receipt of the command signal and unique identifier, preventing laser device operation by the second remote control unit if the second unit does not include the unique identifier with the command signal.

Abstract: A vibrator element includes a drive arm. The drive arm includes an upper surface, a lower surface, a groove opened to the upper surface, and a groove opened to the lower surface. The upper surface is disposed to be deviated by L1 on a +X axis side from the lower surface. The groove is disposed to be deviated by L2 on the +X axis side from the groove. L1 and L2 satisfy a relation of L2/L1>0.

Abstract: A MEMS type inertial sensor comprising a support structure having at least a first seismic body and a second seismic body connected thereto by resilient means in order to be movable in a suspension plane, transducers for maintaining the seismic bodies in vibration and for determining movements of the seismic bodies in the suspension plane, and a control unit connected to the transducers by electrical conductor means. The transducers comprise at least one electrode secured to the first seismic body and at least one electrode secured to the second seismic body, the two electrodes being arranged to enable relative movements of the seismic bodies relative to each other in the suspension plane to be measured directly.

Abstract: A vibration gyroscope circuitry (VCIRC) connectable to a vibrating MEMS gyroscope (VMEMS). The circuitry comprises drive circuitry (DRIVE) arranged to drive, when the circuitry is connected, the vibration MEMS gyroscope (VMEMS) and a measurement unit (DMU) which provides a drive measurement voltage signal (DMV) forming a measure of a displacement of a mass along a drive axis. A sense circuitry (SENSE) is arranged to process a sense measurement signal of the vibration MEMS gyroscope (VMEMS) forming a measure for a displacement of the mass along a sense axis. A digital sample clock generator (SCG) is arranged to generate a sample clock signal (SCLK) from an input signal (FDxy) derivable from a drive measurement voltage signal (DMV). The sample clock generator (SCG) comprises an oscillator (HFOSC) arranged to generate a master clock (MOSC), and a counter unit (OSCCNTR) arranged to count master clock periods during one period of the input signal.

Abstract: Various embodiments each include at least one of systems, methods, devices, and software for GNSS simultaneous localization and mapping (SLAM). The disclosed techniques demonstrate that simultaneous localization and mapping (SLAM) can be performed using only GNSS SNR and geo-location data, collectively termed GNSS data henceforth. A principled Bayesian approach for doing so is disclosed. A 3-D environment map is decomposed into a grid of binary-state cells (occupancy grid) and the receiver locations are approximated by sets of particles. Using a large number of sparsely sampled GNSS SNR measurements and receiver/satellite coordinates (all available from off-the-shelf GNSS receivers), likelihoods of blockage are associated with every receiver-to-satellite beam. Loopy Belief Propagation is used to estimate the probabilities of each cell being occupied or empty, along with the probability of the particles for each receiver location.

Abstract: An information processing device includes: a posture change determining unit that determines, based on an output value of an inertial sensor, whether a posture state of a moving object has changed; a reference orientation generating unit that, when it is determined that the posture state of the moving object has changed from a first posture state into a second posture state, generates a reference orientation corresponding to an orientation of the moving object at that time calculated from the output value of the inertial sensor; and an orientation error calculating unit that, when it is determined that the posture state of the moving object has changed from the second posture state into the first posture state, calculates an error of an orientation of the moving object according to the reference orientation, and an orientation at that time calculated from the output value of the inertial sensor.

Abstract: A user-heading determining system (10) for pedestrian use includes a multiple-axis accelerometer (110) having acceleration sensors; a device-heading sensor circuit (115) physically situated in a fixed relationship to the accelerometer (110); an electronic circuit (100) operable to generate signals representing components of acceleration sensed by the accelerometer (110) sensors, and to electronically process at least some part of the signals to produce an estimation of attitude of a user motion with respect to the accelerometer, and further to combine the attitude estimation (750, ?) with a device heading estimation (770, ?) responsive to the device-heading sensor circuit, to produce a user heading estimation (780); and an electronic display (190) responsive to the electronic circuit (100) to display information at least in part based on the user heading estimation. Other systems, circuits and processes are also disclosed.

Abstract: The invention relates to an alignment method based on a simplified mode allowing processing using an invariant Kalman filter, in which each speed involved in the navigation equations is expressed in a work reference frame (Rt) translated with respect to an inertial reference frame (Ri) and for which the origin moves along a reference inertial trajectory, the carrier of which is assumed to be close (geographic origin for alignment with the sun at known position, GPS trajectory for alignment in-motion, etc.). This simplified mode comprises the repetition of the following steps to estimate a mobile carrier state (P): propagation (PROP) determining an estimated current state from a preceding estimated state, inertial sensor measurements and theoretical information on the carrier trajectory (P) updating (MAJ) the estimated state using theoretical information on the carrier trajectory (P). The deterministic uncertainties of the sensors (bias/drift/scale factors, etc.

Abstract: A vertical-view camera (16) delivers an image signal (ScamV) of the ground overflown by the drone. Gyrometric sensors (102) measure the Euler angles (?, ?, ?) characterizing the attitude of the drone and delivering a gyrometric signal (Sgyro) representative of the instantaneous rotations. Rotation compensation means (136) receive the image signal and the gyrometric signal and deliver retimed image data, compensated for the rotations, then used to estimate the horizontal speeds of the drone. The camera and the inertial unit are piloted by a common clock (160), and it is provided a circuit (170) for determining the value of the phase-shift between the gyrometric signal and the image signal, and to apply this phase-shift value at the input of the rotation compensation means (136) to resynchronize the image signal onto the gyrometric signal before computation of the retimed image data.