Abstract: Techniques are described herein for low-power pedestrian route reconstruction. A method can include accessing location data comprising a set of location points collected by a user device during a workout and defining an initial route. The method can further include accessing map data comprising a plurality of paths within a geographic region. The method can further include, for a plurality of location point pairs of the set of location points, determining a route segment between the pair of location points that follows a path segment of the plurality of paths. The method can further include combining route segments for each location point pair of the plurality of location point pairs to define a reconstructed route that begins with a first location route pair based on an initial location point and ends with a second location route pair based on a final location point.

Abstract: Techniques are described for improving driver efficiency. An example method can include a device accessing sparse location data indicative of one or more geographic locations along a route of the user device during a first time period. The route includes a starting location data point and an ending location data point. The device can access motion data collected by the sensors of the user device. The motion data can be collected by the sensors during the first time period. After a conclusion of the first time period, the device can generate, using the sparse location data and the motion data, a dense data set to reconstruct a route that includes the starting location data point and the ending location data point. The reconstructed route can include second dense location data and velocity data. The device can store the reconstructed route in a local memory of the user device.

Abstract: Described herein are techniques to enable a mobile device to perform multi-source estimation of an altitude for a location. A baseline altitude may be determined at ground level for a location and used to calibrate a barometric pressure sensor on the mobile device. The calibrated barometric pressure sensor can then estimate changes in altitude relative to ground level based on detected pressure differentials, allowing a relative altitude to ground to be determined. Baseline calibration for the barometric sensor calibration can be performed to determine an ambient ground-level barometric pressure.

Abstract: Described herein are techniques to enable a mobile device to perform multi-source estimation of an altitude for a location. A baseline altitude may be determined at ground level for a location and used to calibrate a barometric pressure sensor on the mobile device. The calibrated barometric pressure sensor can then estimate changes in altitude relative to ground level based on detected pressure differentials, allowing a relative altitude to ground to be determined. Baseline calibration for the barometric sensor calibration can be performed to determine an ambient ground-level barometric pressure.

Abstract: A device implementing a system for estimating device orientation includes at least one processor configured to obtain a first estimate for a heading of a device, the first estimate being based on output from a magnetometer of the device. The at least one processor is further configured to capture image data using an image sensor of the device, and determine at least one second estimate of the heading based on correlating the image data with mapping data. The at least one processor is further configured to determine a bias associated with output of the magnetometer based on the first estimate and the at least one second estimate, and adjusting output of the magnetometer based on the determined bias.

Abstract: Location mapping and navigation user interfaces may be generated and presented via mobile computing devices. A mobile device may detect its location and orientation using internal systems, and may capture image data using a device camera. The mobile device also may retrieve map information from a map server corresponding to the current location of the device. Using the image data captured at the device, the current location data, and the corresponding local map information, the mobile device may determine or update a current orientation reading for the device. Location errors and updated location data also may be determined for the device, and a map user interface may be generated and displayed on the mobile device using the updated device orientation and/or location data.

Abstract: In accordance with one or more implementations, a method includes receiving, with an electronic device, a first satellite signal and a second satellite signal and determining whether the first satellite signal is LOS. The determining is based on a signal strength of the first satellite signal. The method also includes determining whether the second satellite signal is non-LOS. The determining is based on a signal strength of the second satellite signal. The method further includes estimating a location of the electronic device based on the first satellite signal and the second satellite signal in response to determining that the first satellite signal is LOS and that the second satellite signal is non-LOS.

Abstract: A device implementing a system for estimating device position includes at least one processor configured to receive a first sensor measurement of a device at a first time, the first sensor measurement having a first variance in measurement error, and to receive a second sensor measurement of the device at a second time, the second sensor measurement having a second variance in measurement error. The at least one processor is further configured to determine a speed of the device based on at least one of the first or second sensor measurements, and adjust the second variance in measurement error based on the determined speed. The at least one processor is further configured to estimate a device position based at least in part on the first variance in measurement error and the adjusted second variance in measurement error.

Abstract: A device implementing a system for device orientation initialization includes at least one processor configured to determine that the device is within or coupled to a vehicle in motion. The at least one processor is configured to employ, in response to the determining, a first position estimation model to estimate a position of the device, and detect occurrence of a predefined condition with respect to employing the first position estimation model. The at least one processor is further configured to switch, in response to detecting occurrence of the predefined condition, from employing the first position estimation model to employing a second position estimation model to estimate the position of the device. The first and second position estimation model apply different respective error state metrics in estimating the position of the device.

Abstract: A device implementing a system for device orientation initialization includes at least one processor configured to determine that the device is within or coupled to a vehicle in motion. The at least one processor is configured to employ, in response to the determining, a first position estimation model to estimate a position of the device, and detect occurrence of a predefined condition with respect to employing the first position estimation model. The at least one processor is further configured to switch, in response to detecting occurrence of the predefined condition, from employing the first position estimation model to employing a second position estimation model to estimate the position of the device. The first and second position estimation model apply different respective error state metrics in estimating the position of the device.

Abstract: A device implementing a system for estimating device location includes at least one processor configured to receive a first estimated position of the device at a first time. The at least one processor is further configured to capture, using an image sensor of the device, images during a time period defined by the first time and a second time, and determine, based on the images, a second estimated position of the device, the second estimated position being relative to the first estimated position. The at least one processor is further configured to receive a third estimated position of the device at the second time, and estimate a location of the device based on the second estimated position and the third estimated position.

Abstract: A device implementing a system for estimating device position includes at least one processor configured to receive a first sensor measurement of a device at a first time, the first sensor measurement having a first variance in measurement error, and to receive a second sensor measurement of the device at a second time, the second sensor measurement having a second variance in measurement error. The at least one processor is further configured to determine a speed of the device based on at least one of the first or second sensor measurements, and adjust the second variance in measurement error based on the determined speed. The at least one processor is further configured to estimate a device position based at least in part on the first variance in measurement error and the adjusted second variance in measurement error.

Abstract: A device implementing a system for estimating device position includes at least one processor configured to receive a first sensor measurement of a device at a first time, the first sensor measurement having a first variance in measurement error, and to receive a second sensor measurement of the device at a second time, the second sensor measurement having a second variance in measurement error. The at least one processor is further configured to determine a speed of the device based on at least one of the first or second sensor measurements, and adjust the second variance in measurement error based on the determined speed. The at least one processor is further configured to estimate a device position based at least in part on the first variance in measurement error and the adjusted second variance in measurement error.

Abstract: Location mapping and navigation user interfaces may be generated and presented via mobile computing devices. A mobile device may detect its location and orientation using internal systems, and may capture image data using a device camera. The mobile device also may retrieve map information from a map server corresponding to the current location of the device. Using the image data captured at the device, the current location data, and the corresponding local map information, the mobile device may determine or update a current orientation reading for the device. Location errors and updated location data also may be determined for the device, and a map user interface may be generated and displayed on the mobile device using the updated device orientation and/or location data.

Abstract: A device implementing a system for estimating device location includes at least one processor configured to receive a first and second set of signals, each set corresponding to location data and being received based on a sampling interval. The at least one processor is configured to, for each sampling period defined by the sampling interval, obtain sensor data corresponding to device motion during the sampling period, determine an orientation of the device relative to that of the vehicle based on the sensor data, calculate a non-holonomic constraint based on the orientation of the device relative to that of the vehicle such that the non-holonomic constraint is iteratively updated, and estimate a device state based on the non-holonomic constraint.

Abstract: Location mapping and navigation user interfaces may be generated and presented via mobile computing devices. A mobile device may detect its location and orientation using internal systems, and may capture image data using a device camera. The mobile device also may retrieve map information from a map server corresponding to the current location of the device. Using the image data captured at the device, the current location data, and the corresponding local map information, the mobile device may determine or update a current orientation reading for the device. Location errors and updated location data also may be determined for the device, and a map user interface may be generated and displayed on the mobile device using the updated device orientation and/or location data.

Abstract: A device implementing a system for estimating device location includes at least one processor configured to receive a first estimated position of the device at a first time. The at least one processor is further configured to capture, using an image sensor of the device, images during a time period defined by the first time and a second time, and determine, based on the images, a second estimated position of the device, the second estimated position being relative to the first estimated position. The at least one processor is further configured to receive a third estimated position of the device at the second time, and estimate a location of the device based on the second estimated position and the third estimated position.

Abstract: A device implementing a system for estimating device location includes at least one processor configured to receive a first estimated position of the device at a first time. The at least one processor is further configured to capture, using an image sensor of the device, images during a time period defined by the first time and a second time, and determine, based on the images, a second estimated position of the device, the second estimated position being relative to the first estimated position. The at least one processor is further configured to receive a third estimated position of the device at the second time, and estimate a location of the device based on the second estimated position and the third estimated position.

Abstract: Described herein are techniques to enable a mobile device to perform multi-source estimation of an altitude for a location. A baseline altitude may be determined at ground level for a location and used to calibrate a barometric pressure sensor on the mobile device. The calibrated barometric pressure sensor can then estimate changes in altitude relative to ground level based on detected pressure differentials, allowing a relative altitude to ground to be determined. Baseline calibration for the barometric sensor calibration can be performed to determine an ambient ground-level barometric pressure.

Abstract: A device implementing a system for estimating device location includes at least one processor configured to estimate a first position of a device based on a first set of parameters, the first set of parameters derived from first sensor data obtained on the device, the first set of parameters corresponding to device motion. The at least one processor is configured to estimate a second position of a user of the device based on a second set of parameters, the second set of parameters derived from second sensor data obtained on the device, the second set of parameters corresponding to user motion. Estimating the first and second positions is constrained by a predefined relationship between the device motion and the user motion. The at least one processor is configured to provide at least one of the first position of the device or the second position of the user.