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12 results about "True north" patented technology

True north (also called geodetic north) is the direction along Earth's surface towards the geographic North Pole or True North Pole. Geodetic north differs from magnetic north (the direction a compass points toward the Magnetic North Pole), and from grid north (the direction northwards along the grid lines of a map projection). Geodetic true north also differs very slightly from astronomical true north (typically by a few arcseconds) because the local gravity may not point at the exact rotational axis of Earth.

Indoor northbound reference precision evaluation method, system, equipment and medium

The invention discloses an indoor northbound reference precision evaluation method, system and device and a medium, and relates to the field of azimuth calibration, and the method comprises the steps: employing a total station cross wire aiming method, and adjusting a total station of each observation station; on the basis of the adjusted total station, measuring an initial true north azimuth angle of the first total station and a first mean error of the initial true north azimuth angle by adopting a polar star arbitrary hour angle method; based on the first total station, determining each transmission angle of the indoor northbound reference and a second median error of the transmission angles, and measuring a plane distance between adjacent total stations; calculating meridian convergence angle correction of each observation station according to an indoor northbound reference transmission sequence; according to the initial true north azimuth angle, each transmission angle and the meridian convergence angle correction number, calculating an indoor north orientation reference; and evaluating the precision of the indoor north orientation reference according to the first middle error and the second middle error. According to the method and the device, the measurement precision of the indoor true north orientation reference is improved, and the reliability of a measurement result is enhanced.
Owner:自然资源部第一大地测量队(自然资源部精密工程测量院陕西省第一测绘工程院)

Methods, devices and electronic equipment for directional placement of corner reflectors

This invention relates to the fields of geodesy and radar engineering technology, and discloses a method, apparatus, and electronic equipment for the directional deployment of corner reflectors. The method includes: determining two measurement reference points in the proposed deployment area of ​​the corner reflector and obtaining the geodetic coordinates of the measurement reference points, and then calculating the reference azimuth angle of the baseline between the measurement reference points relative to true north; using the reference azimuth angle as a reference, marking two auxiliary points in the proposed deployment area of ​​the corner reflector and determining the local physical baseline; obtaining the design azimuth angle of the corner reflector and calculating the azimuth angle difference between the design azimuth angle and the reference azimuth angle; and using the local physical baseline as a reference, directionally deploying the corner reflector according to the azimuth angle difference. The method provided by this invention can still stably obtain an absolute physical reference pointing to true north even in extreme electromagnetic environments such as substations and building complexes, realizing high-precision deployment of corner reflectors in areas with strong interference.
Owner:SHENZHEN SCIENCE & TECHNOLOGY INSTITUTE OF URBAN SAFETY DEVELOPMENT +1

Directional laying method and device of corner reflector and electronic equipment

The invention relates to the technical field of geodetics and radar engineering, and discloses a directional laying method and device for a corner reflector and electronic equipment, and the method comprises the steps: determining two measurement reference points in a region where the corner reflector is to be laid, and obtaining the geodetic coordinates of the measurement reference points, resolving a reference azimuth angle of a reference line between the measurement reference points relative to the true north direction; taking the reference azimuth angle as a reference, marking two auxiliary points in a to-be-arranged area of the corner reflector, and determining a local entity reference line; obtaining a design azimuth angle of the corner reflector, and calculating an azimuth angle difference value between the design azimuth angle and the reference azimuth angle; according to the method provided by the invention, the absolute physical reference pointing to the true north can still be stably obtained in extreme electromagnetic environments such as a transformer substation and a building group, and high-precision layout of the corner reflector in a strong interference area is realized.
Owner:SHENZHEN SCIENCE & TECHNOLOGY INSTITUTE OF URBAN SAFETY DEVELOPMENT +1

Recording type MEMS (Micro Electro Mechanical System) gyro inclinometer

The invention relates to the field of inclinometer equipment, in particular to a recording type MEMS (Micro Electro Mechanical System) gyro inclinometer which comprises an MEMS gyro inclinometer body, when the MEMS gyro inclinometer body is electrified and initialized, different north-seeking modes are selected according to whether a north-seeking instruction is received or not, the MEMS gyro inclinometer body enters an inclinometer state, and a true north position is determined by resolving an earth rotation angular velocity component and original sensor output data; performing error compensation calculation on the original sensor output data according to a preset error compensation model, and outputting accurate sensor output data; in the working process, the motion state is judged according to the output data of the sensor, and the accurate output data of the sensor is continuously updated and corrected through an online automatic correction strategy; and the damping structure module is detachably connected with the MEMS gyro inclinometer body and is used for adapting to different underground tandem connection environments. The combined sensor is adopted, and the intelligent north-seeking algorithm and the error compensation model are combined, so that high-precision inclination measurement in a magnetic interference environment is realized, and the measurement precision and the environmental adaptability are improved.
Owner:NAV TECH CO LTD

Method for determining a calibrated true north azimuth, method for laser communication, laser alignment system

The present disclosure relates to a method for determining a calibrated true north azimuth, a method for laser communication, and a laser alignment system. The calibrated true north azimuth is used for an alignment unit of a laser communication terminal, the laser communication terminal comprising at least a local device and a target device, the method comprising: obtaining coordinate data of the local device and coordinate data of the target device, the coordinate data comprising: longitude, latitude, and altitude; determining a target azimuth and a target elevation of the local device based on the obtained coordinate data of the local device and the coordinate data of the target device; obtaining an alignment date of the local device, so as to determine a true north azimuth corresponding to the target azimuth and corrected by a magnetic declination from a world magnetic field model according to the coordinate data of the local device and the alignment date. The present disclosure can determine a calibrated true north azimuth and perform alignment, thereby improving the alignment accuracy between laser communication devices.
Owner:SHANGHAI QLOONG TECHNOLOGY CO LTD +2

An AR space true north calibration method, device, equipment and medium

This invention relates to an AR spatial true north calibration method, apparatus, device, and medium. The method includes the following steps: acquiring fixed positioning data using an RTK device during movement; selecting a first positioning point and a second positioning point based on the fixed positioning data, calculating the coordinate azimuth between the two positioning points using Gaussian forward and inverse calculations, and calculating the meridian convergence angle at the first positioning point; calculating the angle between the line connecting the first and second positioning points and the true north direction based on the coordinate azimuth and the meridian convergence angle, obtaining the geographic true north direction angle; continuously monitoring the data from the gyroscopes of the RTK device and the AR operating device, and dynamically adjusting the true north direction angle in AR space using a dual-loop control structure based on the geographic true north direction angle to ensure that the AR space is consistent with the real geographic direction. Compared with the prior art, this invention improves the AR spatial direction accuracy from ±5° to ±0.1°, reaching the surveying and mapping grade standard.
Owner:STATE GRID SHANGHAI MUNICIPAL ELECTRIC POWER CO

Mitigating systematic error in gyrocompassing

A MEMS gyrocompass and method are provided to mitigate systematic error in determination of a north angle. The MEMS gyrocompass includes one or more MEMS gyroscopes having a sense axis within a reference plane. Samples from an output of the MEMS gyroscope are obtained in at least two angles of rotation about an axis perpendicular to the reference plane. First fit coefficients are determined by fitting samples with first fitting functions determined as function of time. Second fit coefficients are determined by fitting components of earth rotation rate projected on the reference plane based on samples obtained by all the MEMS gyroscopes, which fitting is performed with a second fitting function determined as a function of rotation angle of the MEMS gyroscope with respect to a reference angle. The north angle is determined as an angle between the reference angle and true north based on the second fit coefficients.
Owner:MURATA MFG CO LTD

Low-orbit satellite vehicle-mounted tracking control method, device and system

PendingCN121050323AProgramme controlComputer controlSatellite trackingIn vehicle
The invention discloses a low-orbit satellite vehicle-mounted tracking control method, device and system. The low-orbit satellite vehicle-mounted tracking control method comprises the steps that the longitude and latitude and the altitude of a vehicle-mounted antenna, the forward included angle between the axial direction of a vehicle-mounted platform and the due north direction and the TLE orbit parameters of a target satellite are obtained; calculating coordinates of the vehicle-mounted platform in an earth coordinate system according to the latitude and longitude of the vehicle-mounted platform and the altitude; calculating the coordinates of the target satellite in an earth coordinate system based on the SGP4 / SDP4 model and the TLE orbit parameters of the target satellite; calculating the coordinate of the target satellite in the station center coordinate system according to the coordinate of the vehicle-mounted platform in the earth coordinate system and the coordinate of the target satellite in the earth coordinate system by taking the vehicle-mounted antenna as a coordinate origin; target satellite tracking control parameters are calculated according to the coordinates of the target satellite in the station center coordinate system; and sending the target satellite tracking control parameters to a vehicle-mounted antenna control unit. According to the invention, after the vehicle carrying platform reaches the target position, the azimuth pitch angle of the low-orbit satellite can be quickly tracked.
Owner:CHENGDU DINGCHENG TAIXIN TECH CO LTD

A method, system, computer device and medium for calibrating an electronic compass

The application discloses a kind of method, system, computer device and medium for calibrating electronic compass using two positioning receivers, and relates to the field of orientation and measurement, including two high-precision positioning equipment and electronic compass system;The longitude and latitude of each antenna is positioned using two high-precision receivers respectively, the angle of straight line formed by two antennas relative to the angle of true north is calculated, and then the direction of straight line formed by two antennas is aligned using electronic compass to obtain the angle of true north, the deviation angle of electronic compass and two antennas is obtained, and finally the deviation angle of electronic compass is corrected.Compared with calibrating electronic compass using true value point, using two high-precision receivers has the advantage of calibration not being limited by the location of true value point, and can be performed at any time in an open field, and the angle of true north of two antennas calculated by two high-precision receivers has high precision, and is suitable for electronic compass correction in true value point-free scenarios.
Owner:HUBEI JIUZHIYANG INFRARED SYST CO LTD

Method and system for measuring due north direction based on solar azimuth solution

PendingCN121953918AImprove reliabilityreduce investmentTheodolitesPrecision engineeringTotal station
The invention relates to the technical field of measurement engineering, and particularly provides a true north direction measurement method and system based on solar azimuth solution, the true north direction measurement method is suitable for a measurement system equipped with a total station and a data processing terminal, and the measurement system is used for true north direction measurement. Comprising the following steps: manually positioning a solar facula by adopting the total station, and after the positioning is completed, enabling a horizontal dial of the total station to be in an observation locking state; calculating a solar azimuth angle at an observation moment on the basis of a sun position algorithm at a data processing terminal, wherein the observation moment is the observation time recorded when the total station completes positioning; and after the horizontal dial reversely rotates the dial reading by the degree of the solar azimuth angle, determining that the pointing direction of the collimation axis of the total station is the true north reference. According to the method, high-precision measurement of the geographical due north direction is realized through solar azimuth calculation, and the precision requirement of precise engineering such as a concentrating solar photo-thermal project on due north reference is met.
Owner:SHAANXI BAOGUANG VACUUM ELECTRIC DEVICE +1

Recording MEMS gyro inclinometer

The present application relates to the field of inclinometer equipment, and specifically relates to a recording type MEMS gyro inclinometer, comprising: a MEMS gyro inclinometer body, when power is turned on and initialized, different north-seeking modes are selected according to whether a north-seeking instruction is received, and a surveying state is entered, the true north direction is determined by solving the earth rotation angular velocity component and the original sensor output data; the original sensor output data is calculated for error compensation according to a preset error compensation model, and accurate sensor output data is output; in the working process, the motion state is judged according to the sensor output data, and the accurate sensor output data is continuously updated and corrected through an online automatic correction strategy; a shock-absorbing structure module is detachably connected between the MEMS gyro inclinometer body, and is used for adapting to different downhole stringing environments. The present application uses a combined sensor, combines an intelligent north-seeking algorithm and an error compensation model, and realizes high-precision surveying in a magnetic interference environment, and improves the measurement precision and environmental adaptability.
Owner:NAV TECH CO LTD