Patent classifications
G01C21/1654
In-flight azimuth determination
The presently disclosed subject matter includes a method and system directed for calculating azimuth of an airborne platform during flight based on IMU measurements, without using GNSS data, gyrocompassing or magnetometers operating on the ground for determining the azimuth.
AUGMENTATION OF GLOBAL NAVIGATION SATELLITE SYSTEM BASED DATA
A vehicle computing system validates location data received from a Global Navigation Satellite System receiver with other sensor data. In one embodiment, the system calculates velocities with the location data and the other sensor data. The system generates a probabilistic model for velocity with a velocity calculated with location data and variance associated with the location data. The system determines a confidence score by applying the probabilistic model to one or more of the velocities calculated with other sensor data. In another embodiment, the system implements a machine learning model that considers features extracted from the sensor data. The system generates a feature vector for the location data and determines a confidence score for the location data by applying the machine learning model to the feature vector. Based on the confidence score, the system can validate the location data. The validated location data is useful for navigation and map updates.
Position tracking inside metallic environments using magneto-electric quasistatic fields
Magneto-electric quasistatic (MEQS) field may be used to track positions of persons and/or objects inside metallic environments. A magneto-electric quasistatic field generator may generate a magneto-electric quasistatic field inside a metallic environment. A magneto-electric quasistatic field detector inside the metallic environment may detect the magneto-electric quasistatic field and generate output signals conveying characteristics of the magneto-electric quasistatic field. The relative position of the magneto-electric quasistatic field detector with respect to the magneto-electric quasistatic field generator may be determined based on the output signals. The position of the magneto-electric quasistatic field detector/generator and/or the position of a person/object carrying the magneto-electric quasistatic field detector/generator may be tracked using the relative position of the magneto-electric quasistatic field detector with respect to the magneto-electric quasistatic field generator.
Method and apparatus for reducing magnetic tracking error
A method and apparatus for reducing magnetic tracking error in the position and orientation determined in an electromagnetic tracking system is disclosed. In some embodiments, a corrected position and orientation is blended with an uncorrected position and orientation based upon the calculated probability of each. To determine a corrected position and orientation, data from an IMU in the receiver is used to obtain a constraint on the orientation. In other embodiments, the amount of detected error due to electromagnetic distortion is measured. Any error is first assumed to be from “floor distortion,” and a correction is applied. If the error is still deemed too great, a constraint is again obtained from IMU data. Using this constraint, another correction for the distortion is made. The solution from this correction may be blended with a standard solution and the solution from the floor distortion to arrive at a final solution.
Determining geographic location of a mobile device using sensor data
In certain embodiments, a mobile device includes a sensor, one or more processors, and a memory. The memory stores computer-executable instructions that, when executed by the one or more processors, cause the one or more processors to perform operations including determining a first geographic location based on wireless signals received as part of a wireless-based mobile device positioning system. The operations include accessing a geographic database that includes data representing a number of geographic locations and properties associated with the geographic locations, and a mapping between measureable values of a type and particular geographic locations. The operations include determining, using the geographic database, candidate geographic locations for adjusting the first geographic location. The operations include accessing a particular value of the type determined according to a measurement of the sensor and determining a second geographic location based on the candidate geographic locations and on the particular value and the mapping.
GEOGRAPHIC AUGMENTED REALITY DESIGN FOR LOW ACCURACY SCENARIOS
To present augmented reality features without localizing a user, a client device receives a request for presenting augmented reality features in a camera view of a computing device of the user. Prior to localizing the user, the client device obtains sensor data indicative of a pose of the user, and determines the pose of the user based on the sensor data with a confidence level that exceeds a confidence threshold which indicates a low accuracy state. Then the client device presents one or more augmented reality features in the camera view in accordance with the determined pose of the user while in the low accuracy state.
System and method for determining real-world geographic locations of multiple members
Methods and systems for determining real-world geographic locations of multiple interconnected members are provided herein. The method may include: determining distances between at least some members of a first subgroup of the multiple members; determining movement vectors of members of a second subgroup of the multiple members; determining real-world geographic locations of members of a third subgroup of the multiple members; and determining, based on the distances between the at least some members of the first subgroup, the movement vectors of the members of the second subgroup and the real-world geographic locations of the members of the third group, the real-world geographic locations of the multiple members.
ORIENTING A MOVING ELECTROMAGNETIC TRACKING REFERENCE FRAME VIA EXTERNAL LOCALIZING DATA ON AN ELECTROMAGNETIC SENSOR USING IMU DATA
A method and apparatus for determining pose of a transmitter, and by extension the pose of one or more receivers, in an electromagnetic tracking system when the transmitter is allowed to move freely in the physical environment. The method operates in a system that incorporates two separate tracking technologies and an Inertial Measurement Unit, one determining the pose of a device relative to a global reference frame and another determining the pose of the same device relative to a local reference frame, thereby avoiding the latency problem and resulting inaccuracy of pose determinations of known prior approaches.
Heading determination device and method, rendering device and method
A heading determination device comprises data input circuitry configured to obtain magnetic field sensor data sensed by a magnetic field sensor in sensor coordinates, position input circuitry configured to obtain a position estimate of the magnetic field sensor, and estimation circuitry configured to derive, from a magnetic map, a local azimuth distortion value in a reference coordinate system at the current position of the magnetic field sensor indicated by the obtained position estimate and to estimate the heading of the magnetic field sensor in the reference coordinate system based on the obtained magnetic field sensor data and the derived local azimuth distortion value.
Methods of attitude and misalignment estimation for constraint free portable navigation
The present disclosure relates to methods of enhancing a navigation solution about a device and a platform, wherein the mobility of the device may be constrained or unconstrained within the platform, and wherein the navigation solution is provided even in the absence of normal navigational information updates (such as, for example, GNSS). More specifically, the present method comprises utilizing measurements from sensors (e.g. accelerometers, gyroscopes, magnetometers etc.) within the device to calculate and resolve the attitude of the device and the platform, and the attitude misalignment between the device and the platform.