Abstract:
To make error correction in a position estimate of a vehicle, visual lane markings on the road can be matched with lane boundaries for the road within 3-D map data. Embodiments include obtaining a “stripe” indicative of an observed lane marking captured in a from a camera image, obtaining map data for the road on which the vehicle is located, determining the plane of the road from coordinates of lane boundaries within the map data, projecting the stripe onto the plane, and comparing the projected stripe with lane boundaries within the map data and associating the visual lane markings with the closest lane boundary. Differences between the projected stripe and the associated lane boundary can then be used for error correction in the position estimate of the vehicle.
Abstract:
Techniques provided herein are directed toward addressing these and other issues by providing robust means for initializing an accelerometer that can take place even while a vehicle is in motion. Specifically, linear acceleration and velocity data can be estimated from wheel speeds, and angular velocity can be estimated with a gyroscope. The vehicle's acceleration can then be computed from these estimates, and subtracted from a total acceleration measured by the accelerometer to determine gravitational acceleration, which can then be accounted for in subsequent measurements taken by the accelerometer. A vehicle velocity may also be determined based on the vehicle's estimated angular velocity and linear velocity. Embodiments may also employ techniques for translating measurements taken in one coordinate frame to another coordinate frame for estimate determination and/or outlier compensation.
Abstract:
Methods, apparatuses, and computer-readable media are described. In one example, a method of controlling a vehicle comprises: receiving, using one or more sensors, a first set of measurements of a set of physical attributes of the vehicle in a motion; determining, based on a motion data model that defines a set of relationships among the set of physical attributes of the vehicle in the motion and based on the first set of measurements, a set of expected measurements of the set of physical attributes; determining whether to use an entirety of the first set of measurements to control an operation of the vehicle based on comparing the first set of measurements and the set of expected measurements; and responsive to determining not to use the entirety of the first set of measurements, controlling the operation of the vehicle based on a second set of measurements.
Abstract:
A method for ranging includes randomly selecting a symbol in each of at least two successive sub-cycles of a ranging cycle, transmitting symbol IDs corresponding to the randomly selected symbols and a sequence ID, and transmitting a ranging signal with the sequence ID on each of the randomly selected symbols.
Abstract:
Determining a position of a device using a signal received from a reference emitter includes: receiving the signal; determining a state of a first filter, the state of the first filter including a first carrier phase ambiguity estimate that includes a floating value; determining a state of a second filter, the state of the second filter including a second carrier phase ambiguity estimate that includes a fixed value; determining whether the state of the second filter is consistent with one other filter state or measurement; maintaining the state of the second filter in response to the device determining that the state of the second filter is consistent with the other filter state; changing the state of the second filter to the state of the first filter in response to the device determining that the state of the second filter is not consistent with the other filter state.
Abstract:
A range between a first wireless device and a second wireless device is estimated using a first mechanism based on messages transmitted over a first communication channel. The first communication channel is associated with a first radio access technology capability of the wireless devices. One or more metrics indicative of an accuracy of the range estimates provided by the first mechanism are obtained. A second mechanism to estimate a range between the first wireless device and the second wireless device may be implemented in favor of the first mechanism when the metric fails to satisfy a criterion. The second mechanism is based on unicast messages transmitted over a second communication channel. The second communication channel is associated with a second radio access technology capability of the wireless devices and may be the same as, or different from, the first communication channel.
Abstract:
A method for aligning visual-inertial odometry (VIO) and satellite positioning system (SPS) reference frames includes obtaining a plurality of range-rate measurements of a mobile platform from an SPS. The range-rate measurements are with respect to a global reference frame of the SPS. The method also includes obtaining a plurality of VIO velocity measurements of the mobile platform from a VIO system. The VIO velocity measurements are with respect to a local reference frame of the VIO system. At least one orientation parameter is then determined to align the local reference frame with the global reference frame based on the range-rate measurements and the VIO velocity measurements.
Abstract:
A range between a first wireless device and a second wireless device is estimated using a first mechanism based on messages transmitted over a first communication channel. The first communication channel is associated with a first radio access technology capability of the wireless devices. One or more metrics indicative of an accuracy of the range estimates provided by the first mechanism are obtained. A second mechanism to estimate a range between the first wireless device and the second wireless device may be implemented in favor of the first mechanism when the metric fails to satisfy a criterion. The second mechanism is based on unicast messages transmitted over a second communication channel. The second communication channel is associated with a second radio access technology capability of the wireless devices and may be the same as, or different from, the first communication channel.
Abstract:
Disclosed are methods, devices, systems, apparatus, servers, computer-/processor-readable media, and other implementations, including a method of estimating a range between a first wireless device and a second wireless device that includes obtaining, at the first wireless device, first information related to a first broadcast message transmitted by the first wireless device, and obtaining, at the first wireless device, second information related to a second broadcast message transmitted by the second wireless device, with the second broadcast message including at least some of the first information. The method also includes determining the range between the first wireless device and the second wireless device based, at least in part, on the first information and the second information.