Abstract: A parasitically-coupled dual-band patch antenna is described. The antenna includes an inner conductor having one or more feed holes. The antenna also includes an outer conductor surrounding the inner conductor in a radial direction. The antenna further includes one or more feeds each having a vertical portion that passes through the feed holes and a horizontal portion that extends in an outward direction from the feed holes toward the outer conductor. The feeds are conductively connected to the outer conductor. The horizontal portion of each of the feeds is separated from and is conductively disconnected from a top surface of the inner conductor.

Abstract: A device for determining coordinates of a location can include two GNSS receiver antennas positioned in fixed relation to each other and separated by a short baseline. Signals received from the two receiver antennas can be processed to estimate a degree to a multipath effect may be impairing reliability of observables extracted from the received signals. Where both antennas observe signals at the same carrier frequency from the same satellite, each antenna can determine a carrier phase, and a single-difference carrier phase (SDCP) can be computed and used to estimate multipath effects. Where both antennas observe signals at two (or more) carrier frequencies from the same satellite, a “geometry-free” SDCP can be computed and used to estimate multipath effects. Observations of different satellites can be weighted based on the estimated multipath effects.

Abstract: Techniques for autonomous vehicle boundary intersection detection and avoidance are described. In an example, a geofence boundary is received at a display coupled to a control module of a vehicle. A 2D footprint is generated using a definition of the vehicle and an implement coupled to the vehicle. Using geographic coordinates for the vehicle, a current position and orientation for the footprint are determined. A 2D projection footprint is generated for the vehicle using the current position and orientation, a current steering state, and a direction of travel. A first distance from the current position and orientation at which the projection footprint intersects with the boundary is determined. Based on the first distance, the speed of the vehicle is maintained at or below a maximum speed.

Abstract: A data format embodied on a medium, wherein the data format defines an alignment for a linear construction infrastructure, wherein the data format comprises a series of points, each point defining a position on the alignment, wherein each point comprises: (i) a horizontal geographic coordinate of the point; (ii) a chainage number of the alignment at the point; and (iii) a horizontal direction of the alignment at the point.

Abstract: The present disclosure provides a surveying instrument. The surveying instrument comprises a center unit comprising an optical device and a front lens. The optical device is arranged to emit and/or receive light through the front lens along an optical axis (OA) of the center unit. The surveying instrument further comprises an alidade on which the center unit is rotatably arranged about a first axis (A1). The alidade comprises a tilt sensor arranged along a second axis (A2). The second axis is orthogonal to the first axis. The alidade further comprises an optical arrangement arranged to form an optical path from a first side of the alidade to an aperture arranged along the second axis at a second side of the alidade. The optical path bypasses the tilt sensor.

Abstract: Described herein are systems, methods, and other techniques for compensating for antenna phase center and SNR variation in dual- and multi-antenna GNSS receivers. Satellite signals are received at a GNSS receiver having a plurality of antennas including a first antenna and a second antenna. GNSS measurements are collected based on the received wireless signals using the first and second antennas. A horizontal orientation of the plurality of antennas with respect to a transmitting satellite is estimated. One or both of an antenna phase center correction and an SNR correction are obtained from one or more calibration tables based on the horizontal orientation. A geospatial position of the GNSS receiver is estimated using the GNSS measurements and one or both of the antenna phase center correction and the SNR correction.

Abstract: A target (100) for use in surveying applications is provided. The target comprises a plurality of light sources (106) arranged around a longitudinal axis (A) of a base element (108) of the target. The plurality of light sources is configured to emit light radially. The target further comprises a sensor unit (216) a control unit (214). The control unit is configured to obtain information regarding an orientation (?) of said target relative to a surveying instrument (120) aimed at the target, based on at least a measurement received from the sensor unit. The control unit is further configured to identify, based on the obtained information regarding the orientation of the target relative to the surveying instrument, a first subset (106c-106e) of the plurality of light sources arranged to emit light towards the surveying instrument, and a second subset (106a, 106b, 106f-106h) of the plurality of light sources arranged to emit light away from the surveying instrument.

Abstract: A method for aligning two surveying instruments in a common space in a process that uses an autocollimation of a collimated light beam transmitted by a first surveying instrument and reflected by a second surveying instrument. In the alignment process, the first surveying instrument may emit a collimated light beam towards the second the surveying instrument and receive a reflection of the collimated light beam from the second surveying instrument in an autocollimator. The reflection may be generated for example by a mirror at the second surveying instrument. When the light beam is reflected such that autocollimation of the collimated light beam is achieved at the first surveying instrument, the first and second surveying instruments are in a predetermined positional relation with respect to one another.

Abstract: A total station includes a telescope and a tracking system for aligning an axis of the total station with a target. The tracking system includes a first emitter that emits first light toward the target and a first sensor that receives the first light reflected off the target. The first emitter and first sensor are horizontally offset from a lens center of the telescope. The tracking system also includes a second emitter that emits second light toward the target and a second sensor that receives the second light reflected off the target. The second emitter and second sensor are vertically offset from a lens center of the telescope. Corrective rotations are computed based on the received first light and the received second light.

Abstract: Described herein are systems, methods, and other techniques for generating a ground coverage map that indicates portions of a site that have been modified by a vehicle operating within the site. First and second modifier data regarding an operation of a site modifier device of the vehicle at first and second times are captured using a site modifier sensor attached to the vehicle. First and second coverage regions are predicted based on the first and second modifier data, the first and second coverage regions corresponding to regions within the site that are modified by the site modifier device at the first and second times. First and second coverage images are computed based on the first and second coverage regions. The first and second coverage images are accumulated to generate the ground coverage map.

Abstract: A modeling system accesses a mesh model generated via a light detection and ranging (LiDAR) scan of an environment comprising a room, the mesh model including anchors corresponding to walls, a floor, and a ceiling of the room. The modeling system generates, based on the anchors in the mesh model, alternate walls for a modified mesh model, the alternate walls corresponding to mesh facets of the mesh model. The modeling system modifies a configuration of the mesh facets of the alternate walls to generate the modified mesh model. The modeling system renders a three-dimensional (3D) model of the environment from the modified mesh model.

Abstract: Described herein are systems, methods, and other techniques for performing conflation between target road polylines and source road polylines stored in GIS databases. A pairing of a target road polyline and a source road polyline is obtained. The target road polyline and the source road polyline each include a sequence of connected 2D or 3D vertices that form a continuous line. A similarity score is computed between the target road polyline and the source road polyline based on one or more similarity metrics. A conflation classification is assigned to the target road polyline, the source road polyline, or the pairing based on the similarity score. The conflation classification is one of a set of possible conflation classifications. A post-classification action is performed based on the conflation classification.

Abstract: A method for reducing the risk of jamming during determination of the polarity of navigation bits in a GNSS signal. More than a threshold number of 1s or 0s are considered to be jamming data, and are ignored in two areas. First, they are ignored in generating a lookup table when determining which bits are historically risky bits in navigation acquisition. Second, they are ignored during a current navigation acquisition, since such bits may be due to current jamming efforts.

Abstract: A surveying system comprises a base 3, a first alidade 7 mounted on the base and rotatable relative to the base about a first axis 9, a first optical instrument 17 mounted on the first alidade 7, wherein the first optical instrument is configured to emit a first beam 41 of measuring light, a second alidade 19 mounted on the base and rotatable relative to the base about a second axis 21, and a second optical instrument 25 mounted on the second alidade, wherein the second axis substantially coincides with the first axis. The first optical instrument includes a scanner 31, and the second optical instrument includes at least one camera 63.

Abstract: Measurement devices such as total stations or laser scanners equipped with camera sensors can capture an image of an environment. An image segmentation model can identify and segment environmental features in the image. The measurement device can display an overlay of the segmented features on top of the image. When a user selects a particular feature, the measurement device can perform point measurements such as scanning to measure a portion of the environment associated with the selected feature. Features in the environment not selected by the user may not be included in the point measurements.

Abstract: Techniques for capturing and displaying point clouds using an AR device are described. A GNSS point of the AR device is determined based on received satellite signals. A depth image is captured while the AR device is positioned at the GNSS point. The depth image is projected into 3D space to obtain a point cloud having a set of points. An accuracy of the GNSS point is determined. In response to determining that the accuracy of the GNSS point is below a threshold, the GNSS point is determined to be a low-accuracy GNSS point, points from the set of points that are outside of a zone surrounding a previously determined high-accuracy GNSS point are removed, and remaining points from the set of points that are inside the zone are displayed on a display of the AR device.

Abstract: Some embodiments pertain to generating, transmitting, and using ionospheric disturbance information applicable to at least a part of the Earth's surface. The ionospheric disturbance information is transmitted in the form of at least one message comprising reference point ionospheric disturbance levels, i.e. levels associated with a plurality of reference points on a reference ionospheric shell. On the receiver side, an estimator is operated, and, for each of at least one NSS signal observed by a NSS receiver, the reference point ionospheric disturbance levels are used to decide whether to adopt some ionospheric disturbance mitigation measures in the context of estimating parameters useful to determine a position. The ionospheric disturbance information may for example comprise ionospheric amplitude scintillation information, ionospheric phase scintillation information, and/or ionospheric gradient information. Systems, vehicles, and computer programs are also disclosed.

Abstract: A surveying prism can include a housing, optical features, and a bumper. The optical features can be located on a radial surface of the housing azimuthally offset from one another by equal arcs. The bumper can cover the optical features. The bumper can include flat edges and position indicators. The flat edges can correspond to the optical features. Each flat edge can have a different first center point of first center points that is approximately at the same azimuthal angle with respect to the surveying prism as a corresponding second center point of a corresponding optical feature of the optical features. The position indicators can correspond to the optical features, and each position indicator can be positioned at a central point of a different flat edge of the flat edges.

Abstract: A control device receives, from an engine load sensor device, a value of an engine load of an engine of an equipment operating in an operating environment. The control device compares the value of the engine load to a target engine load range defined by a minimum target engine load value and a maximum target engine load value. Responsive to determining that the value of the engine load is less than the minimum target engine load value, the control device lowers a cutting blade of the equipment to increase an engagement of the cutting blade with a surface or subsurface. Responsive to determining that the engine load is greater than the maximum target engine load value, the control device raises the cutting blade of the equipment to decrease the engagement of the cutting blade with the surface or subsurface.

Abstract: Techniques include establishing a first tunnel that transmits a first packet between a first backhaul node of a first local mesh network and a server. The techniques further include, responsive to the second backhaul node moving out of wireless communication range of the first local mesh network, establishing a second tunnel that transmits packets between the second backhaul node of a second local mesh network and the server. The techniques further include receiving the first packet from the first backhaul node in the first local mesh network transmitting the first packet to the second backhaul node.