Abstract: A distributed navigation system includes navigation platforms, each having a universal navigation processor, relative navigation systems to provide source information to the navigation platforms, navigation filters provided on one or more of the universal navigation processors, and an anchor navigation node disposed on one or more of the navigation platforms to form one or more anchor navigation platforms. Each anchor navigation node includes an inertial navigation system, a clock, and absolute navigation systems, which are used, in combination with source information, to determine navigation information. The anchor navigation platforms provide the navigation information to other navigation platforms.

Abstract: A distributed navigation system includes navigation platforms, each having a universal navigation processor, relative navigation systems to provide source information to the navigation platforms, navigation filters provided on one or more of the universal navigation processors, and an anchor navigation node disposed on one or more of the navigation platforms to form one or more anchor navigation platforms. Each anchor navigation node includes an inertial navigation system, a clock, and absolute navigation systems, which are used, in combination with source information, to determine navigation information. The anchor navigation platforms provide the navigation information to other navigation platforms.

Abstract: An image-based navigation system is arranged to obtain a terrain image of a target terrain from one or more image sensors at a low altitude imaging location. The terrain image includes at least one celestial image feature and at least one terrain feature. Map database information stored in at least one hardware memory device is accessed and compared to the at least one celestial image feature and the at least one terrain feature in the terrain image to determine absolute location coordinates of the imaging location.

Abstract: A distributed navigation system architecture includes a plurality of navigation platforms, each having a universal navigation processor configured to communicate with other universal navigation processors, one or more relative navigation systems configured to provide source information to the navigation platforms, an anchor navigation node disposed on one or more of the plurality of navigation platforms in order to form one or more anchor navigation platforms, the anchor navigation node, including an inertial navigation system, a clock, and one or more absolute navigation systems, configured to determine navigation information based on the inertial navigation system, the clock, the one or more absolute navigation systems and optionally the source information, the one or more anchor navigation platforms providing the navigation information to the other navigation platforms, and a navigation processor system in communication with each of the universal navigation processors in order to provide operating informat

Abstract: Methods and apparatus automatically determine a location, such as of an aircraft or spacecraft, by matching images of terrain below the craft, as captured by a camera, radar, etc. in the craft, with known or predicted terrain landmark data stored in an electronic data store. A star tracker measures attitude of the camera. An additional navigation aiding sensor provides additional navigational data. Optionally, a rangefinder measures altitude of the camera above the terrain. A navigation filter uses the attitude, the additional navigational data, and optionally the altitude, to resolve attitude, and optionally altitude, ambiguities and thereby avoid location solution errors common in prior art terrain matching navigation systems.

Abstract: A digital camera optically couples a monocentric lens to image sensor arrays, without optical fibers, yet shields the image sensor arrays from stray light. In some digital cameras, baffles are disposed between an outer surface of a monocentric lens and each image sensor array to shield the image sensor arrays from stray light. In other such digital cameras, an opaque mask defines a set of apertures, one aperture per image sensor array, to limit the amount of stray light. Some digital cameras include both masks and baffles.

Abstract: An image-based navigation system is arranged to obtain a terrain image of a target terrain from one or more image sensors at a low altitude imaging location. The terrain image includes at least one celestial image feature and at least one terrain feature. Map database information stored in at least one hardware memory device is accessed and compared to the at least one celestial image feature and the at least one terrain feature in the terrain image to determine absolute location coordinates of the imaging location.

Abstract: A visual navigation system includes a compass configured to orient a user in a heading direction, an image sensor configured to capture a series of successive navigation images in the heading direction, one or more of the navigation images having at least two reference markers, data storage memory configured to store the series of successive navigation images, a navigation processor configured to identify at least one principal marker and at least one ancillary marker from the at least two reference markers, the principal marker positioned within a principal angle and the ancillary marker positioned within an ancillary angle, which is greater than the principal angle, and to determine heading direction information based on a position of the at least one principal marker and/or the at least one ancillary marker in the successive navigation images, and a user interface configured to provide the heading direction information to the user.

Abstract: Methods and apparatus automatically determine a location, such as of an aircraft or spacecraft, by matching images of terrain below the craft, as captured by a camera, radar, etc. in the craft, with known or predicted terrain landmark data stored in an electronic data store. A star tracker measures attitude of the camera. An additional navigation aiding sensor provides additional navigational data. Optionally, a rangefinder measures altitude of the camera above the terrain. A navigation filter uses the attitude, the additional navigational data, and optionally the altitude, to resolve attitude, and optionally altitude, ambiguities and thereby avoid location solution errors common in prior art terrain matching navigation systems.

Abstract: A distributed navigation system architecture includes a plurality of navigation platforms, each having a universal navigation processor configured to communicate with other universal navigation processors, one or more relative navigation systems configured to provide source information to the navigation platforms, an anchor navigation node disposed on one or more of the plurality of navigation platforms in order to form one or more anchor navigation platforms, the anchor navigation node, including an inertial navigation system, a clock, and one or more absolute navigation systems, configured to determine navigation information based on the inertial navigation system, the clock, the one or more absolute navigation systems and optionally the source information, the one or more anchor navigation platforms providing the navigation information to the other navigation platforms, and a navigation processor system in communication with each of the universal navigation processors in order to provide operating informat

Abstract: An image-based navigation system is arranged to obtain a terrain image of a target terrain from one or more image sensors at a low altitude imaging location. The terrain image includes at least one celestial image feature and at least one terrain feature. Map database information stored in at least one hardware memory device is accessed and compared to the at least one celestial image feature and the at least one terrain feature in the terrain image to determine absolute location coordinates of the imaging location.

Abstract: Methods and apparatus automatically determine a location, such as of an aircraft or spacecraft, by matching images of terrain below the craft, as captured by a camera, radar, etc. in the craft, with known or predicted terrain landmark data stored in an electronic data store. A star tracker measures attitude of the camera. Optionally, a rangefinder measures altitude of the camera above the terrain. A navigation filter uses the attitude, and optionally the altitude, to resolve attitude, and optionally altitude, ambiguities and thereby avoid location solution errors common in prior art terrain matching navigation systems.

Abstract: A visual navigation system includes a compass configured to orient a user in a heading direction, an image sensor configured to capture a series of successive navigation images in the heading direction, one or more of the navigation images having at least two reference markers, data storage memory configured to store the series of successive navigation images, a navigation processor configured to identify at least one principal marker and at least one ancillary marker from the at least two reference markers, the principal marker positioned within a principal angle and the ancillary marker positioned within an ancillary angle, which is greater than the principal angle, and to determine heading direction information based on a position of the at least one principal marker and/or the at least one ancillary marker in the successive navigation images, and a user interface configured to provide the heading direction information to the user.

Abstract: A star tracker determines a location or orientation of an object, such as a space vehicle, by observing unpolarized light from one or more stars or other relatively bright navigational marks, without imaging optics, pixelated imaging sensors or associated pixel readout electronics. An angle of incidence of the light is determined by comparing signals from two or more differently polarized optical sensors. The star tracker may be fabricated on a thin substrate. Some embodiments have vertical profiles of essentially just their optical sensors. Some embodiments include micro-baffles to limit field of view of the optical sensors.

Abstract: Methods and apparatus automatically determine a location, such as of an aircraft or spacecraft, by matching images of terrain below the craft, as captured by a camera, radar, etc. in the craft, with known or predicted terrain landmark data stored in an electronic data store. A star tracker measures attitude of the camera. Optionally, a rangefinder measures altitude of the camera above the terrain. A navigation filter uses the attitude, and optionally the altitude, to resolve attitude, and optionally altitude, ambiguities and thereby avoid location solution errors common in prior art terrain matching navigation systems.

Abstract: A chip scale star tracker that couples starlight into a lightguide such that the angle of incidence partially determines the mode of propagation of the starlight in the lightguide. A baffle system integrated with the lightguide prevents propagation of light incident from a predetermined range of angles.

Abstract: Methods and apparatus ascertain a geographic position based on topographic contours of ocean surfaces. Observed ocean topographic contours are matched to predicted ocean topography and/or ocean topographic information stored in a database. Such systems and methods do not necessarily require INS, GPS, RF beacons, optical beacons or celestial sightings. These systems and methods may be used as references to correct INS. These systems and methods may be used to ascertain a geographic location of an aircraft, spacecraft, watercraft, landcraft (vehicle), person or the like. Similarly, these systems and methods may be used as part of a guidance system for guiding a craft to a destination. These systems and methods may be used in tandem with, or as backups for, other types of navigation or guidance systems or as one input to a navigation filter.

Abstract: A digital camera optically couples a monocentric lens to image sensor arrays, without optical fibers, yet shields the image sensor arrays from stray light. In some digital cameras, baffles are disposed between an outer surface of a monocentric lens and each image sensor array to shield the image sensor arrays from stray light. In other such digital cameras, an opaque mask defines a set of apertures, one aperture per image sensor array, to limit the amount of stray light. Some digital cameras include both masks and baffles.

Abstract: A chip scale star tracker that couples starlight into a lightguide such that the angle of incidence partially determines the mode of propagation of the starlight in the lightguide. A baffle system integrated with the lightguide prevents propagation of light incident from a predetermined range of angles.

Abstract: A chip scale star tracker that captures plane-wave starlight propagating in free space with a wafer-thin angle-sensitive broadband filter-aperture, and directs the light into a waveguide structure for readout. Angular information about the star source is determined from characteristics of the starlight propagating in the waveguide. Certain examples include internal propagation-constant-based baffling to elimination stray light from extreme angles.