摘要:
The invention relates to a surveying subsystem comprising a camera module and a control and evaluation unit, the surveying subsystem (1) being adapted to be used as part of a surveying system that is adapted to determine positions of a position measuring resource, particularly a GNSS-antenna (15) or a retro-reflector mounted - together with the surveying subsystem - on a surveying pole (10). The images taken by the camera - when moving along a path through a surrounding - are used within a SLAM process, so as to determine poses for the images and - using said pose information - so as to compute a point cloud comprising 3D-positions of points of the surrounding by forward intersection using the images. According to the invention, the control and evaluation unit has stored a program with program code for performing the steps of □ identifying objects of a pre-defined and/or user-defined kind in the images and □ modifying or deleting - in the computed point cloud - 3D-positions of points being connected to the identified objects. In Particular, the pre-defined kinds of objects may be a user (2) operating the surveying system (1), parts of the surveying system (1), human faces and/or vehicle license plates.
摘要:
A system for detecting localized ground position changes makes use of plurality of lighting units, each fixed to the ground. Each lighting unit comprises a positioning system and a transmitter for transmitting positioning information to a remote central processing unit. The positioning information from the plurality of fixed lighting units is processed to identify local ground position changes. The infrastructure of a networked lighting system in this way enables ground information to be determined, for example for detecting ground movement in response to natural events or man-made activities (such as tunneling, building, extraction of natural resources etc.).
摘要:
A method of determining location of a user device includes receiving global navigation satellite system (GNSS) fix data that represents GNSS calculated position of the user device. The method further includes receiving signal strength data associated with each satellite communicating with the user device, and receiving map information regarding environment surrounding the user device. The received GNSS fix data and signal strength data is provided to a non-linear filter, wherein the non-linear filter fuses the GNSS fix data and signal strength data to generate an updated position estimate of the user device. In addition, the non-linear filter utilizes probabilistic shadow matching estimates that represent a likelihood of received signal strength data as a function of hypothesized user device locations within the environment described by the received map information.
摘要:
There is provided a positioning system that comprises a GPS device including a GPS receiver arranged to receive GPS satellite signals from a plurality of GPS satellites and an attenuation device arranged to attenuate GPS satellite signals such that when a GPS satellite is located in a first portion of sky the GPS satellite signals received by the GPS receiver from said GPS satellite are attenuated. A storage is provided to store satellite location information for the plurality of GPS satellites over time at a location of the GPS receiver, and a controller is provided to determine location information of the GPS device based on received GPS information from the GPS device, wherein the received GPS information comprises information on signal strengths of the GPS satellite signals received by the GPS receiver. If a signal strength for a first GPS satellite is lower than a threshold signal strength at a point in time then the controller is arranged to determine that the first GPS satellite is in the first portion of the sky and determine angle information of the GPS device relative to earth's normal and/or orientation information of the GPS device in a horizontal plane using the stored satellite location information.
摘要:
Disclosed embodiments relate to a method for determining an estimate of a value relating to a parameter of a wireless receiver device, comprising: (1) obtaining first data relating to the wireless receiver device and/or the state of the positioning system; (2) establishing, based on the first data, a plurality of hypotheses regarding at least one device parameter value of the wireless receiver device; (3) obtaining second data descriptive of at least two EM signals actually received by the wireless receiver device from a set of at least two transmitters, respectively; (4) determining at least two levels of correspondence between I) at least two of the plurality of hypotheses and II) one or more signal parameter values relating to the at least two actually received EM signals, respectively; and (5) determining, based on the at least )two determined levels of correspondence, an estimate relating to a parameter of the wireless receiver device.
摘要:
Device (100) has: a low-speed interval extraction unit (120) for extracting, from GPS information, a low-speed interval extending from the location at a first time point at which the measured speed of a vehicle has fallen below a prescribed value, to the location at a second time point at which the speed has exceeded the prescribed value; a vehicle speed transition model generating unit (130) for generating a model having, as constraint condition, the length and the amount of time of the low-speed interval, for indicating temporal transition of the speed in such a way that the speed continuously increases to the second time point after having decreased from the first time point; and a stop determination unit (140) for determining that the vehicle has stopped within the low-speed interval, on the condition that an interval in which the speed is zero or less is present within the model.
摘要:
The invention relates to a method for determining position using GNSS (Global Navigation Satellite Systems) by means of an antenna assembly (6) having a number of antennae (1-5) and a received-signal evaluation assembly (20) arranged downstream of the antenna assembly and supplied with the antennae received signals (A1-A5), the evaluation assembly containing GNSS receivers (21-25) that are connected to the antennae (1-5) and have a downstream evaluation device (26). In order to develop a method of this type in such a way that a particularly high reliability in position determining is possible with relatively low expenditure, an antenna assembly (6) is used, in which the antennae (1-5) are oriented with different direction vectors, and in relation to each detectable satellite (31-33), respective antennae received signals (A1-A5) of all antennae (1-5) are detected with regard to their satellite-related signal-to-noise ratio, thus forming satellite-specific signal-to-noise ratio measured values. From the satellite-specific signal-to-noise ratio measured values, in relation to each satellite (e.g. 31), the satellite-specific signal-to-noise ratio measured values that are positively distinguished in their signal-to-noise ratio from other signal-to-noise ratio measured values relating to the same satellite (e.g. 31) are selected. A respective satellite-related main direction vector signal is formed from each of the direction vector signals of the antennae, the satellite-specific signal-to-noise ratio measured values of which are selected, and the satellite-related main direction vector signals are compared with the orientation vector signals characterising the position of the respective satellites in orbit; in the event of minor deviations a position indication (N) is given. The invention also relates to an assembly for determining position.
摘要:
The method is meant for the evaluating of the amount of micro and macro cracks in the pavement of a traffic lane, such as a road or street. The colder water beneath the pavement is under the load of heavy traffic pumped into the micro and macro cracks in the pavement and lowers the temperature of the pavement, so a large difference between the temperatures in different points on the pavement reveals a large amount of cracks. In the method, the examination span of the traffic lane is first selected. Thereafter the temperature T1 of the heavily loaded part of the pavement of the selected examination span and the temperature T2 of the lightly loaded part of the pavement of the same examination span are determined. A difference AT between the determined temperatures is calculated, which difference is compared to a reference value. If the difference is larger than the used reference value, the pavement lets through a significant amount of water. If the difference is smaller than the used reference value, the condition of the pavement is sufficiently good. The temperatures t r of the heavily loaded part of the pavement are measured at the wheel ruts and the temperatures t k of the lightly loaded part of the pavement are measured in the area outside the wheel ruts. The temperatures of the pavement are measured with an apparatus, which is placed in a vehicle travelling on the traffic lane. Alternatively the emissivity ε r of the heavily loaded part of the pavement and the emissivity ε k of the lightly loaded part of the pavement can be determined and the difference Δε can be compared to a reference value.