Abstract: The various technologies presented herein relate to fabrication and operation of a heat exchanger that is configured to extract heat from an underlying substrate. Heat can be extracted by way of an air gap formed between an impeller and a baseplate. By utilizing a pump to create an initial air gap that is further maintained by rotation of the impeller relative to the baseplate, a spring can be utilized that can apply a force of greater magnitude to the impeller than is used in a conventional approach, thus enabling the weight of the impeller to be negligible with respect to a width of the air gap, thereby conferring the desirable feature of orientation independence with respect to gravity with no performance degradation.

Abstract: A heat exchanger with a multi-zone heat transfer surface is disclosed. The heat exchanger includes a fluid flow passage extending between and interconnecting a fluid inlet and a fluid outlet. A heat transfer surface is disposed within the fluid flow passage wherein the heat transfer surface includes at least one heat transfer-reducing zone disposed in thermal contact with a portion of at least one of the walls of the fluid flow passage and at least one heat transfer-augmenting zone disposed in thermal contact with a portion of the at least one of the walls of the fluid flow passage. The configuration of the heat transfer-augmenting zones with the heat-transfer-reducing zones is such that heat transfer across the surface of the heat exchanger in contact with the heat transfer-augmenting zones is increased relative to the heat transfer across the surface of the heat exchanger in contact with the heat transfer-reducing zones.

Abstract: The present invention relates to a strengthened radiator comprising a collector and a water tank, the water tank being provided with a wall (40) and a base (50), a plurality of plates (10) located inside the water tank, wherein each plate (10) comprises a plurality of extensions (20, 20?, 20?, 20??) having a predetermined format; the base (50) of the wall (40) of the water tank being provided with a plurality of slots (30) having a format corresponding to that of the plurality of extensions (20, 20?, 20?, 20??), wherein each extension of the plurality of extensions engages each slot of the corresponding plurality of slots.

Abstract: A brazed plate heat exchanger comprises a number of heat exchanger plates (100) provided with a pressed pattern comprising ridges (R) and grooves (G). The ridges and grooves of neighboring plates contact one another in order to keep the plates on a distance from one another under formation of interplate flow channels for media to exchange heat when the heat exchanger plates are placed in a stack to form the heat exchanger. Means (120a, 120b) are provided for allowing temperature measurement of a fluid present in a second flow channel counted from an end of the stack of heat exchanger plates (100).

Abstract: A heat exchange system having desired anti-scaling performance and an anti-scaling method thereof are disclosed. The heat exchange system at least comprises a load control unit, a temperature and pressure detection unit and an anti-scaling treatment unit. The heat exchange system conditions bonding ways of water quality in a HVAC chiller unit, an air compressor, a heat exchanger, a cooling unit, or a boiler under a variety of scaling conditions in both field operation and water quality, by integrating the interaction of those units together with the anti-scaling method for simulating water quality that has a water quality limit same as that in field operation. The heat exchange system further integrates with a testing of anti-scaling performance to make water quality no longer charged and lose the reaction power so as to prevent scaling formation, enhance the anti-scaling performance, and ensure operating efficiency and performance.

Abstract: A firearm has a lower receiver with a first channel formed in a first surface of the lower receiver, and an upper receiver attached to the lower receiver at a pivot point. A compressible material is disposed within the first channel between the upper receiver and lower receiver. The upper receiver compresses the compressible material when the upper receiver closes onto the lower receiver. A recess can be formed within the first channel and extends into the lower receiver deeper than the first channel. A second channel is formed in a second surface of the lower receiver. Alternatively, the lower receiver has a slot formed in a surface of the lower receiver, and the compressible material is disposed within the slot. The slot includes a bottom surface and vertical surface extending from the bottom surface to the surface of the lower receiver, and rounded ends.

Abstract: An M240 machine gun barrel assembly with a barrel with a muzzle end at the distal end of the barrel and a breach end at the proximal end of the barrel; a handle connector connecting the barrel to a handle assembly; and the handle assembly having a free end and a connected end, the connected end operably connected to the handle connector; the handle assembly operable between a first position with the free end of the handle assembly pointing proximally and a second position with the free end of the handle assembly pointing distally.

Abstract: Embodiments of adjustable gas block devices and methods of using the same are described. In one embodiment, an adjustable gas block device includes a gas block to communicate gas from a gas port in a barrel to a gas tube. The adjustable gas block may also include an orifice ring to select one of a plurality of preset gas flow settings for controlling the flow of gas between the barrel and the gas tube. Additionally, the adjustable gas block may include a spring ring to retain the orifice ring setting.

Abstract: A firearm has a barrel, a trigger, a bolt assembly and a magazine well with a longitudinal direction, in which a magazine is movably accommodated in the longitudinal direction. A manually actuable slide is movable substantially transversely to the longitudinal direction. The slide engages on a driver connected to the magazine and moves the driver with the magazine from a safety position into a feed position.

Abstract: The crossbow includes a frame, a first limb and a second limb connected to the frame, a first cam and a second cam mounted on opposite sides of an axis of arrow travel, a string connecting the first cam and the second cam, a first cable connecting the first cam and the first limb, and a second cable connecting the second cam and the second limb. The first cam and the second cam are mounted on a holder of the first cam and a holder of the second cam. The first cam is arranged entirely between the axis of arrow travel and a loose end of the first limb. The second cam is arranged entirely between the axis of arrow travel and a loose end of the second limb. The crossbow reduces overall dimensions of an arrow throwing device while maintaining arrow speed by changing a traditional position of cams.

Abstract: A ballistic adjusting structure of toy gun is capable of allowing a bullet to be in a hopping up status and includes: a base; an inner barrel; a robbing cylinder having a robbing part; an adjusting pipe having a free end and a pivotal end pivoted to the base and formed with a spiral guiding slot; an operation member having a driven part penetrated into the spiral guiding slot and a driving part operating the robbing cylinder. When the free end is driven by an external force to drive the pivotal end to be rotated, the driven part is guided by the spiral guiding slot to drive the driving part to be displaced, and the displacement of the driving part is able to operate on the robbing cylinder for altering a location where the robbing part is arranged in the inner barrel.

Abstract: The valve device includes a main member for installing on a toy gun and connecting to a high-pressure gas source. Inside the main member, there is a first chamber, a second chamber connected to the first chamber, and an inlet channel. A valve member is movably housed in the main member. The valve member includes a valve channel, a through hole, an inlet blocking element, and an outlet blocking element. The valve member selectively blocks the connection between the first chamber and the inlet channel. As such, the pressure difference between the second chamber and the high-pressure gas source drives the valve member to selectively block the inlet channel, without using a spring to control the valve member. The valve device therefore has enhanced operation life and reduced cost.

Abstract: An aiming device is provided including a body, an illumination device associated with the body and an optical element, where the illumination device is operable to selectively display a dot on the optical element being visible to a user. The optical element can include an upper edge and a lower edge, and the dot can display closer to the upper edge than to the lower edge, in some cases in the upper half or one third of the height of the optical element. The device can include a protective frame to which the optical element is joined, and the optical element upper edge can be unconcealed by any part of the protective frame above the upper edge, falling within an open top span of the frame. The optical element can be removable and replaceable relative to the protective frame, with a retainer plate temporarily securing the element to the frame.

Abstract: An adjustable laser sight is described to be utilized with a firearm and a select ammunition having a known trajectory. The sight has an outer housing and a movable laser diode. The sight also includes a vertical adjuster for varying the vertical angle of the diode. The vertical adjuster has a turret with a series of detent holes therein which mesh with a spring biased detent. The turret detent holes are unevenly spaced from each other, with the spacing increasing between each successive pair of turret detent holes. Each turret detent hole is associated with a progressively increasing incremental target distance mark on the turret. A first bushing is rotatably coupled to the turret and is rotatably coupled to a second bushing with camming members. The second bushing also has an internally threaded adjustment screw therein for even adjustment of the laser diode.

Abstract: A target marking system includes a light source emitting a thermal beam having a predetermined temporal modulation, and an optics assembly directing the thermal beam to impact a target, the target directing radiation to the optics assembly in response to the impact. A portion of the radiation having the predetermined temporal modulation. The target marking system further includes a detector configured to distinguish the portion of the radiation having the predetermined temporal modulation from a remainder of the radiation, the portion of the radiation passing to the director through the optics assembly. The system also includes a readout integrated circuit, the detector directing an input signal to the readout integrated circuit, and the readout integrated circuit producing a digitally enhanced output signal in response to receipt of the input signal.

Abstract: This invention discloses a riflescope wherein the point of aim is adjusted by attaching one or more corrector wedge prisms in front of the objective. Each wedge prism shifts the point of aim by a predetermined amount such as 5 cm at 100 m or 10 cm at 100 m, etc. A shooter can zero-in his rifle by first firing a set of test shots to determine how far off the bullets hit from the desired point of impact. He then selects one or more wedge prisms supplied with the riflescope and attaches them to its front side. The wedge prisms correct the riflescope's point of aim and bring it in alignment with the the rifle's point of impact. The riflescope introduced in this invention has no moving parts, no turrets and no off-axis optical components. There is no possibility of it's point of aim shifting due to rifle's recoil force or other vibrations. Additionally, the riflescope has a streamlined body which is aesthetically pleasing and also suitable for adding auxiliary sights such as a reflector sight.

Abstract: The invention relates to a protective clothing unit, in particular a protective clothing unit having fragment protection, preferably having a protective function against fragments created and/or released by detonation and/or explosion, comprising outerwear and/or underwear and possibly comprising separate head and/or face protection, neck protection, shoulder protection, arm protection, hand protection, trunk protection, torso protection, genital and/or anal protection, and/or leg protection, wherein the protective clothing unit has fragment protection elements, preferably textile fragment protection elements, which are specific and different from each other and which are associated with different body regions when worn and/or cover different body regions when worn, preferably having a protective function against fragments created and/or released by detonation and/or explosion.

Abstract: A system for protecting and alerting individuals in indoor environments of active shooter incidents includes a foldable shield wall, a bulletproof door panel, a foot bolt, an early warning blue light system (EWBLS), and at least one key fob. The foldable shield wall, the bulletproof door panel, and the foot bolt are mounted adjacent to each other. The foldable shield wall is mounted to a structural wall of a room, wherein the room is within a building, so that the foldable shield wall functions as a barrier between the victims and active shooter. The bulletproof door panel is mounted onto a main entry door of the room. The foot bolt is mounted onto the main entry door. Both the door panel and the foot bolt reinforce the existing entry door to withstand gunfire and force entry. The at least key fob is communicably coupled with the EWBLS.

Abstract: The invention provides a system and method for intercepting a target UAV by releasing a plurality of countermeasure (CM) objects in a projected path thereof to form a 3D countermeasure cloud. Pieces of flexible materials configured to become ensnared in the propellers of the target UAV or otherwise interfere with their ability to provide lift and thrust capabilities to the UAV. A UAV interception control system may track the target UAV and compute a location probability volume therefor using a modified Kalman filter to decide on a projected interception location and time.

Abstract: The invention relates to a stun gun with illumination and siren. The stun gun generates a high-voltage pulse instantaneously through the transformer, stuns the contacted creature into dazed or shock for self-defense. The function of existing stun gun is relatively single, and the structure is not compact enough, it is inconvenient for use. If integrating more function in the existing stun gun, the structure of the stun gun will be complicated and it will be even more inconvenient for use.

Abstract: A resettable target system is provided. The resettable target system includes a base member and a support framework attached to the base member. A faceplate is attached to the support framework and a shaft is supported by the support framework. A plurality of target plate assemblies is supported for rotation by the shaft. The plurality of target plate assemblies is rotatable between a first inclined orientation and a second resting orientation. A reset framework is supported for rotation by the shaft. The reset framework is configured to rotate the plurality of target plate assemblies from the second resting orientation to the first inclined orientation.

Abstract: A disc launching device includes a long handle and a disc holder at one end of the handle. The handle may include a grip end for holding the handle, an attachment end opposite the grip end, and a shaft extending from the grip end to the attachment end. The disc holder is attached to the attachment end of the handle. It includes a front rail for holding one side of a disc, a back rail for holding an opposite side of the disc, and at least one support member extending between the front rail and the back rail. The front rail and the back rail form an opening on one side of the disc holder, configured to allow the disc to launch out of the disc holder through the opening when sufficient forward momentum is applied to the disc holder via the handle.

Abstract: Assemblies and methods for the electrical grounding of an initiator for a vehicle device, e.g. an inflator. Initiator assemblies are provided for inflators in electrical charge transmitting connection via a connector assembly to an electric ground. Initiator assemblies include integrally molded initiator having a molded base forming a connector socket. The molded base includes a grounding clip recess feature. A metallic electrical grounding clip is housed in the grounding clip recess feature. The grounding clip includes a base portion and an extending portion. The extending portion includes a first end proximate and in contact with the base portion and a second end distal from the base portion and with second end in electrical transferring contact with the vehicle device.

Abstract: The present invention provides a subsonic ammunition cartridge including a polymeric casing body comprising a generally cylindrical hollow polymer body having a body base at a first end thereof and a mouth at a second end to define a propellant chamber; a propellant insert positioned in the propellant chamber to reduce the internal volume of the propellant chamber, wherein the propellant chamber has an internal volume that is at least 10% less than the open internal volume of a standard casing of equivalent caliber; and a primer insert positioned at the body base and in communication with the propellant chamber.

Abstract: The invention relates to a projectile (1), which has a projectile body (2) featuring a recess (5) for receiving an explosive, wherein the projectile body (2) has a rotation-symmetrical shell surface (7), at least in sections, which is surrounded, at least in sections, by several ring-shaped elements (8) provided with predetermined break points, wherein fragments (12) formed upon breakup of the elements (8) are predefined via the predetermined break points, said fragments (12) being connected to one another in a ring-shaped connecting portion (11) for forming the ring-shaped element (8), and the freely projecting ends (13) of the fragments (12) being at least partially arranged in a common orthogonal plane (13?) to a longitudinal axis (8?) of the ring-shaped element (8), wherein this orthogonal plane (13?) is arranged diverging from an orthogonal plane (11?) defined by the ring-shaped connecting portion (11), as well as to a corresponding ring-shaped element (8) for the projectile (1).

Abstract: A remote delivery device is disclosed which has a tubular body and a tubular tail piece. The tail piece is adapted to telescope part way into body and has a plurality of stop members provided at a desired axial position. The stop members are located at spaced-apart locations around an outer circumferential surface of the tail piece and extend radially outwardly beyond an inside diameter of the body so that a forward tail end of the tail piece can be inserted into the body only to the location of the said stop members at the desired axial position. The body is crimped onto said tail piece at the desired axial position with a rearmost edge of the body abutting the stop members.

Abstract: The present invention relates to the military field. It discloses a contact fuse for multi-purpose aircraft ammunition, characterised in that it comprises an electromechanical arming system that is easy to manufacture and does not contain any explosive material inside of same. In addition, said fuse is characterised in that it comprises an alert system that reveals a possibly unsafe condition on the ground and in that it is structurally straightforward to manufacture.

Abstract: A tool for identifying a correct belt for a system of pulleys from a plurality of prefabricated belts having different lengths is disclosed. The tool may include a belt track attached to a first end portion of a measurement belt. The measurement belt may be wrapped around the system of pulleys. An opposed second end portion of the measurement belt may be disposed adjacent to the belt track which may include a reference indicator. The reference indicator will be aligned to one of a plurality of measurement markings on the second end portion which indicates the correct belt to order from among the plurality of prefabricated belts.

Abstract: The detector for a surface measuring device includes: an arm including a contact at a tip end of the arm; a rotation shaft configured to rotatably support the arm; a transmission part having one end connected to the arm at a position on a side opposite to the contact with respect to the rotation shaft; an elastic part having one end connected to another end of the transmission part and configured to generate a measuring force to be applied to the contact; a position adjusting part connected to another end of the elastic part and configured to move a position of the another end of the elastic part in a moving direction; and a tilt adjusting part connected to the arm and including a contact part arranged at position where the contact part can be brought into contact with the transmission part.

Abstract: A tool for inspecting an annular section of an engine includes a first segment extending along a first lengthwise direction between a forward end and an aft end; and a second segment extending along a second lengthwise direction between a forward end and an aft end, the forward end of the first segment pivotably coupled to the aft end of the second segment and the first segment moveable relative to the second segment between a bent position and a coupled position, the first lengthwise direction defining a coupled angle with the second lengthwise direction when the first segment is in the coupled position relative to the second segment. The tool also includes an adjustment member operable with the first segment, the second segment, or both to adjust the coupled angle defined by the first lengthwise direction with the second lengthwise direction.

Abstract: The invention relates to a device and a method for tactile/optical measuring of geometric features and structures on a workpiece. In order to be able to precisely align the probe extension for performing precise measurements without problems, a probe is proposed comprising a probe extension (13) having a flexurally elastic design at least in segments and having a mounting segment for mounting in a receptacle (14) comprising a mounting segment (60) implemented as a rotational lock.

Abstract: Optical axes of lens units of measurement heads are adjusted so as to be parallel to each other. The lens unit includes a diffraction lens. When adjusting the optical axis, in a state where the measurement heads face each other with a reference member interposed therebetween, light having a plurality of wavelengths are emitted from the measurement heads to one surface and the other surface of the reference member, respectively. Intensities of primary light having one wavelength, which are reflected by one surface and the other surface of the reference member respectively, and incident on the measurement heads through each of a path of a multi-order light having other wavelengths are displayed on a main display unit as information indicating a degree of orthogonality of the optical axes of the measurement heads with respect to the one surface and the other surface of the reference member.

Abstract: Manufacturing of a shoe is enhanced by creating 3-D models of shoe parts. For example, a laser beam may be projected onto a shoe-part surface, such that a projected laser line appears on the shoe part. An image of the projected laser line may be analyzed to determine coordinate information, which may be converted into geometric coordinate values usable to create a 3-D model of the shoe part. Once a 3-D model is known and is converted to a coordinate system recognized by shoe-manufacturing tools, certain manufacturing steps may be automated.

Abstract: A three-dimensional measurement device includes: a projector that includes: a light source that emits predetermined light; and a reflective optical modulator that converts the predetermined light into a predetermined striped pattern, wherein the projector projects the predetermined striped pattern onto a measurement object at a predetermined number of frames per unit time; an imaging device that takes an image of the measurement object projected with the predetermined striped pattern; a processor that: controls the projector and the imaging device to sequentially project a plurality of different ones of the predetermined striped pattern and take images of the plurality of different ones of the predetermined striped pattern to obtain a plurality of image data having different light intensity distributions; and executes three-dimensional measurement of the measurement object based on the plurality of image data.

Abstract: A projection device can include: an illuminating unit for emitting light; and a projection unit having a mirror surface, the projection unit being designed to project the light emitted by the illuminating device by means of the mirror surface into an object space and to shape it into different spatially structured light patterns in the object space. The projection device is distinguished in that the mirror surface is deformable, at least in regions, and in that the projection unit, for forming the different spatially structured light patterns in the object space, has at least one actuator for deforming the mirror surface, at least in regions. The present subject matter furthermore relates to a projection method, to a device, and to a method for detecting a three-dimensional contour.

Abstract: Methods and systems for feed-forward of multi-layer and multi-process information using XPS and XRF technologies are disclosed. In an example, a method of thin film characterization includes measuring first XPS and XRF intensity signals for a sample having a first layer above a substrate. The first XPS and XRF intensity signals include information for the first layer and for the substrate. The method also involves determining a thickness of the first layer based on the first XPS and XRF intensity signals. The method also involves combining the information for the first layer and for the substrate to estimate an effective substrate. The method also involves measuring second XPS and XRF intensity signals for a sample having a second layer above the first layer above the substrate. The second XPS and XRF intensity signals include information for the second layer, for the first layer and for the substrate.

Abstract: A system and method for processing a flexible part comprising holding the flexible part securely in an unconstrained position using a holder; and controlling a positioner to process the flexible part based on a comparison of a shape and/or position of the flexible part in the unconstrained position with design specifications of the part not in the unconstrained position.

Abstract: Inertial measurement method and apparatus for a mobile entity perform a filtering process for an angular velocity signal, an alignment process where an approximate initial attitude angle is calculated from acceleration and angular velocity signals and then precisely adjusted, an angular velocity/acceleration bias calculation process where angular velocity bias is calculated by subtracting Earth's angular velocity from the angular velocity signal and an acceleration bias is calculated by subtracting gravitational acceleration from the acceleration signal, an attitude angle calculation process where an angular velocity is calculated by subtracting Earth's angular velocity and the angular velocity bias from the angular velocity signal, and an attitude angle is calculated by integrating the angular velocity, a location movement amount calculation process where acceleration is calculated by subtracting the gravitational acceleration and the acceleration bias from the acceleration signal, and calculate a location m

Abstract: A flexible display capable of improving an angle-measuring accuracy using different kinds of sensors and a method of measuring an angle thereof. The flexible display includes a first sensor unit disposed in a first region and including different kinds of sensors, a second sensor unit disposed in a second region adjacent to the first region and including different kinds of sensors, and an angle-measuring unit measuring a folding angle between the first region and the second region in response to sensing signals outputted from the first sensor unit and the second sensor unit.

Abstract: Determining when an estimated altitude of a mobile device can be used for calibration or location determination. Particular systems and methods determine an area in which the mobile device is expected to reside, determine an altitude value of each section of a plurality of sections in the area, determine if the altitude values meet a threshold condition, and determine that the estimated altitude of the mobile device can be used for determining the position of the mobile device or for calibrating a pressure sensor of the mobile device when the altitude values meet the threshold condition.

Abstract: A method and a device for determining and displaying a flyaway distance for a rotorcraft in the event of an engine of the rotorcraft failing, and while taking account of the height of waves being overflown by the rotorcraft. The method includes a first determination for determining a flyaway distance of the rotorcraft in the event of a failure of an engine and under current flying conditions, a second determination for determining a maximum altitude of the waves being overflown by the rotorcraft and displaying the flyaway distance and the maximum altitude on a display instrument of the rotorcraft indicating the relative height of the rotorcraft or else its altitude. A safety margin is preferably added to the maximum altitude of the waves, or else to the flyaway distance of the rotorcraft.

Abstract: A surveying instrument comprises a monopod installed at a reference point, a surveying instrument main body provided at the monopod and having an attitude detector, wherein the surveying instrument main body carries out an image pickup and a scanning of an object to be measured at a pre-movement and a post-movement respectively, obtains at least three cross points of a locus of a scan pattern of the pre-movement and the post-movement, and calculates three-dimensional coordinates of an installation point of the post-movement based on three-dimensional coordinates of the cross points measured from the reference point, a measurement result of the cross points measured from the installation point of the post-movement and a detection result of the attitude detector.

Abstract: A compass for attachment to a hat, particularly a brim of a hat. The compass includes a housing, an attachment-clip, at least one direction-sensor, a controller, a display-screen and a power-supply. In a preferred embodiment, the power-supply is a solar panel and a rechargeable battery. The compass is useful for attaching to the hat to allow hands-free use of the compass.

Abstract: A method of tuning a vibratory gyroscope, the gyroscope comprising: an axisymmetric disc resonator, a frame, the resonator fixed to the frame through at least three separate anchors, a plurality of electrodes, each electrode positioned on the frame or the resonator, wherein the plurality of electrodes comprises at least one drive electrode through which a drive signal is input to excite a first mode of vibration of the resonator, at least one first sense electrode configured to sense the first mode of vibration of the resonator, at least one second sense electrode configured to sense a second mode of vibration of the resonator, orthogonal to the first mode, and at least first and second tuning electrodes to which DC biasing voltages may be applied, the method comprising the steps of: a) applying an AC drive signal to the drive electrode, the drive signal comprising a plurality of frequencies; b) sensing the response of the resonator to the drive signal at the first and second sense electrodes; c) determining

Abstract: A signal processing apparatus according to an embodiment of the present technology includes an acceleration arithmetic unit. The acceleration arithmetic unit extracts, on a basis of a first detection signal and a second detection signal, the first detection signal including information related to an acceleration along at least a uniaxial direction and having an alternating-current waveform corresponding to the acceleration, the second detection signal including the information related to the acceleration and having an output waveform in which an alternating-current component corresponding to the acceleration is superimposed on a direct-current component, a dynamic acceleration component and a static acceleration component from the acceleration.

Abstract: Techniques are disclosed for systems and methods for video based sensor fusion with respect to mobile structures. A mobile structure may include at least one imaging module and multiple navigational sensors and/or receive navigational data from various sources. A navigational database may be generated that includes data from the imaging module, navigational sensors, and/or other sources. Aspects of the navigational database may then be used to generate an integrated model, forecast weather conditions, warn of dangers, identify hard to spot items, and generally aid in the navigation of the mobile structure.

Abstract: A system and method include generating environment data from skylight sensor data. The environment data includes a value of a geospatially dependent parameter associated with light received from a predetermined celestial light source. At least two of a compass direction of the predetermined celestial light source when the skylight sensor data was received, a time at which the skylight sensor data was received, or a geospatial coordinate at which the skylight sensor data was collected are received. At least one of the compass direction of the predetermined celestial light source when the skylight sensor data was received, the time at which the skylight sensor data was received, or the geospatial coordinate at which the skylight sensor data was collected is determined, at least in part, from the environment data.

Abstract: Systems, methods, and other techniques for providing dynamically responsive feedback to a transit user are disclosed. Location data regarding a plurality of locations of the transit user within a transit system may be detected by a tracking device. An intent to validate is received from the transit user. Based on the intent to validate, it is determined that a successful validation has occurred. Based on the location data, the plurality of locations are determined. Based on the plurality of locations, a location and a velocity of the transit user are determined. Instructions for a feedback signal are generated based on the location and the velocity. A feedback device positioned within the transit system is caused to output the feedback signal, indicating the successful validation.

Abstract: Methods, architectures, apparatuses, systems, devices, and computer program products directed to dead reckoning for pedestrian navigation (“pedestrian dead reckoning”) and robust heading estimation in pedestrian dead reckoning. Pursuant to the methodologies and technologies provided herein, a walking direction may be derived or otherwise determined using a robust heading estimation mechanism in connection with, for example, step detection and step length determination. The robust heading estimation mechanism may be based on device orientation (e.g., on changes in device orientation). The device orientation may be obtained based on (e.g., by way of) fusion of accelerometer and gyroscope measurements.

Abstract: A method, system and computer program product are disclosed for providing a measure of pedestrian congestion in a given area. In one embodiment, the method comprises collecting data from a pedestrian moving in the area, and using the data to determine one or more specified parameters representing a pattern of movement of the pedestrian in the area. These specified parameters are used to determine a sinuosity of pedestrian traffic in the given area. In one embodiment, the pattern of movement is a walking pattern of the pedestrian, and the data collected from the pedestrian identifies a multitude of positions of the pedestrian's feet. In an embodiment, the specified parameters include a lateral gap between the feet of the pedestrian, and a length of a stride of the pedestrian. A sequence of values may be collected for each of these parameters.