CN113091709A - Novel GNSS receiver inclination measuring method - Google Patents
Novel GNSS receiver inclination measuring method Download PDFInfo
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- G01C9/00—Measuring inclination, e.g. by clinometers, by levels
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- G—PHYSICS
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- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
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- G01C21/165—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation combined with non-inertial navigation instruments
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Abstract
The invention provides a novel GNSS receiver inclination measuring method, which comprises the following steps: step (1): factory correction; step (2): time synchronization; and (3): initializing a state; and (4): GNSS/MEMS fusion resolving; and (5): tilt compensation; and (6): displaying the inclined state; and (7): and the inclination precision evaluation realizes the continuous and high-precision inclination measurement without correction so as to replace an inclination measurement method based on an electronic compass technology and a shaking technology, improve the working efficiency of the field measurement of the GNSS receiver and reduce the labor intensity of a measurer.
Description
Technical Field
The invention belongs to a scheme design and implementation method of a GNSS receiver high-precision inclination measurement system, and is suitable for the measurement fields of point measurement and lofting surveying and mapping, engineering measurement, monitoring and the like by utilizing a GNSS receiver and a centering rod.
Background
The GNSS receiver measures the coordinate position of the antenna phase center, and what is needed in practical application is the coordinate position of the corresponding point at the bottom end of the centering rod, the traditional operation mode needs to maintain the level bubble on the centering rod to be centered, the antenna phase center position is transmitted to the measuring point corresponding to the bottom end of the measuring rod, the operation efficiency is low, the labor intensity is high, the environments such as a corner and a slope do not have the objective condition that the level bubble is centered, the inclination measurement technology does not need to maintain the centering rod to be vertical, the GNSS receiver measurement technology is a change, the labor intensity can be reduced, and the operation efficiency is improved.
Firstly, decomposing a length vector of a centering rod which is unchanged under a carrier coordinate system to a navigation coordinate by determining a space vector conversion relation between the receiver carrier coordinate system (IMU coordinate system) and the navigation coordinate system (ECEF earth center earth fixed coordinate system and a local horizontal coordinate system), and directly performing centering rod length compensation on the position of an antenna phase center in the navigation system so as to realize measurement of a ground measuring point (figure 1); secondly, a multi-position measuring method based on the space intersection theory (figure 2);
the current scheme based on the first category is mainly an electronic compass tilt measurement method, which determines the space vector transformation relation between a receiver carrier coordinate system and a navigation coordinate system, the essence of the method is to determine attitude angles (pitch angle, roll angle and course angle) between a carrier system and a navigation system, coordinate conversion of tilt measurement does not relate to stretching, but only relates to rotation and translation, a tilt measurement scheme based on an electronic compass tracks the pitch angle and the roll angle of a GNSS receiver by using an accelerometer and a gyroscope, the gyroscope is an optional sensor, the output of the magnetometer is adjusted to the horizontal plane by using the pitch angle and the roll angle, therefore, magnetic heading is calculated, a heading angle is obtained through magnetic declination compensation, a direction cosine matrix is generated by using a pitch angle, a roll angle and the heading angle, coordinate conversion of space vectors is realized, the antenna phase center position is compensated to a ground measuring point, but the defects are more:
the absolute accuracy of the pitch angle and the roll angle depends on the performance of the accelerometer, the requirements on performance indexes of the accelerometer such as zero offset, zero offset stability and the like are high, strict calibration needs to be carried out regularly, and precise calibration equipment and a strict calibration environment are needed, which are not possessed by common customers;
because the accelerometer cannot distinguish the motion acceleration from the gravity acceleration, the electronic compass tilt measurement technology can only carry out tilt measurement under a quasi-static condition, and even if a gyroscope is added to increase the dynamics of angle tracking, real-time tilt measurement still cannot be realized due to the existence of IMU system errors and random errors;
the magnetometer needs to be corrected before being used every time, the correction effect directly influences the accuracy of course angle measurement, the magnetometer is easily influenced by the change of the internal and external electromagnetic environments of the receiver in the using process, and the change is difficult to monitor, so the reliability of the measured value of the magnetometer is poor;
because the inclination measuring scheme based on the electronic compass has the defects of incapability of ensuring absolute precision, tedious correction, poor reliability and the like, a measurer is unwilling to use and dare to use in practical application.
The method mainly comprises the steps of measuring a plurality of points in space by shaking a centering rod, calculating the position of a measuring point by taking the length of the centering rod as a constraint condition to perform space intersection, but is influenced by the geometrical structure of space point distribution, particularly the environments such as corner and the like, the distribution of the space points is limited, the geometrical structure is poor, so that the precision of the measuring point is unstable, the accuracy of a decimeter level can only be achieved, and the inclination measurement can be completed only by measuring a plurality of space points.
Disclosure of Invention
In order to solve the defects, the invention provides a novel GNSS receiver inclination measurement method, which realizes the continuous high-precision inclination measurement without correction, and is reliable, so as to replace the inclination measurement method based on the electronic compass technology and the shaking technology, improve the working efficiency of the GNSS receiver field measurement and reduce the labor intensity of a measurer.
The invention provides a novel GNSS receiver inclination measuring method, which comprises the following steps:
step (1): factory correction;
step (2): time synchronization;
and (3): initializing a state;
and (4): GNSS/MEMS fusion resolving;
and (5): tilt compensation;
and (6): displaying the inclined state;
and (7): and (5) evaluating the inclination precision.
The method described above, wherein the step (2) specifically includes: the time synchronization of GNSS data and IMU data is realized based on the PPS pulse signal of the GNSS receiver, so that the real-time performance and the dynamic performance of inclination measurement are ensured.
The method described above, wherein the step (3) specifically includes: and the initialization of the position, the speed and the attitude is completed by utilizing the position and the speed information of the GNSS, so that an initial state is provided for the GNSS/MEMS fusion solution.
The method described above, wherein the step (4) specifically includes: and (3) constructing a kinematic equation of a Kalman filter on the basis of an error equation arranged by an inertial machine, and taking the position and speed information of the GNSS as measurement input, thereby realizing the data fusion resolving and the real-time estimation of the position, the speed and the attitude of the GNSS/MENS.
The method described above, wherein the step (5) specifically includes: decomposing the constant centering rod vector under the carrier coordinate system to a navigation system on the basis of the three-dimensional attitude, and performing centering rod length compensation on the antenna phase center position under the navigation system so as to obtain the position of the measuring point under the navigation system.
The method described above, wherein the step (6) specifically includes: the calculation of the inclination angle and the inclination direction of the centering rod is realized on the basis of the three-dimensional attitude information, so that the description of the inclination state of the centering rod is facilitated; the step (7) specifically comprises: and deducing the standard deviation of the position of the compensation point according to the error propagation law by using the three-dimensional attitude standard deviation estimated by the GNSS/MEMS fusion algorithm, thereby realizing the precision evaluation of the tilt compensation.
The invention has the following beneficial effects: the method realizes the reliable continuous high-precision inclination measurement without correction so as to replace an inclination measurement method based on an electronic compass technology and a shaking technology, improve the working efficiency of the field measurement of the GNSS receiver and reduce the labor intensity of a measurer.
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The invention and its features, aspects and advantages will become more apparent from reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings. Like reference symbols in the various drawings indicate like elements. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
Fig. 1 and 2 are schematic diagrams of a conventional tilt measurement technique, respectively.
FIG. 3a is a schematic diagram of a GNSS/INS data fusion algorithm of the present invention; FIG. 3b is a schematic diagram of the system of the present invention.
Fig. 4a and 4b are schematic diagrams illustrating a synchronous calibration method for IMU system errors and installation errors.
FIG. 5 is a schematic diagram of the PPS time synchronization principle of the present invention.
FIG. 6 is a schematic diagram of the walking GNSS/INS fusion solution state initialization scheme of the present invention.
Detailed Description
In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention.
In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The following detailed description of the preferred embodiments of the invention, however, the invention is capable of other embodiments in addition to those detailed.
Referring to fig. 1 to 5, the novel GNSS receiver inclination measurement system provided by the present invention includes an Inertial Measurement Unit (IMU), a GNSS receiver, a CPU, a centering rod, wherein the inertial measurement unit includes a 3-axis accelerometer and a 3-axis gyroscope, and does not include a 3-axis magnetometer, thereby fundamentally avoiding the problem that the magnetometer needs to be corrected and is easily affected by electromagnetic environment changes, which is significantly different from the electronic compass inclination measurement scheme in that the inertial measurement unit is installed at the center position of the GNSS receiver for measuring the linear acceleration and the angular velocity of the receiver, and performs inertial mechanical arrangement and calculation by using the measured acceleration and angular velocity, and participates in constructing a motion model for GNSS/MEMS data fusion calculation;
the GNSS receiver is mainly used for measuring the position and the speed of the antenna phase center of the receiver and providing a PPS pulse synchronization signal, the position of the antenna phase center is a position reference of inclination measurement, the position and the speed of the antenna phase center are observation input of a GNSS/MEMS data fusion model, and the PPS pulse signal is a reference of time synchronization of GNSS data and IMU observation data;
the CPU is a data processing center and is responsible for the synchronization of GNSS data and IMU data, the operation of a GNSS/MEMS data fusion algorithm, the calculation of tilt compensation and the calculation of a compensation point precision evaluation index; the method fully exerts the high dynamic property and the high reliability of the inertial sensing based on the GNSS/MEMS data fusion algorithm, can give the result of the inclination measurement in real time, has the precision reaching centimeter level, and has obvious difference from the inclination measurement scheme of 'shaking one for shaking' in the aspects of use efficiency and precision;
the centering rod is the physical medium for the GNSS receiver and the measurement point location transfer.
The invention provides a novel GNSS receiver inclination measuring method, which comprises the following steps: step (1): and (5) factory calibration: the invention provides a factory calibration method for synchronously calibrating an IMU system error and an installation error, thereby avoiding the influence of systematic errors on the inclination measurement precision;
step (2): time synchronization: the method realizes the time synchronization of the GNSS data and the IMU data based on the PPS pulse signal of the GNSS receiver, thereby ensuring the real-time property and the dynamic property of the inclination measurement;
and (3): state initialization: the invention fully utilizes the position and speed information of the GNSS to complete the initialization of the position, the speed and the attitude, thereby providing an initial state for the GNSS/MEMS fusion calculation;
and (4): GNSS/MEMS fusion resolving: the kinematic equation of the Kalman filter is constructed on the basis of the error equation of the inertial mechanical arrangement, and the position and speed information of the GNSS is taken as measurement input, so that the data fusion calculation and the real-time estimation of the position, the speed and the attitude of the GNSS/MENS are realized;
and (5): and (3) tilt compensation: decomposing a constant centering rod vector under a carrier coordinate system to a navigation system on the basis of a three-dimensional attitude, and performing centering rod length compensation on the central position of an antenna phase under the navigation system so as to obtain the position of a measuring point under the navigation system;
and (6): and displaying the inclined state: the method and the device realize the calculation of the inclination angle and the inclination direction of the centering rod on the basis of the three-dimensional attitude information, thereby facilitating the description of the inclination state of the centering rod;
and (7): evaluation of the inclination accuracy: according to the method, the three-dimensional attitude standard deviation estimated by a GNSS/MEMS fusion algorithm is used, and the compensation point position standard deviation is deduced according to an error propagation law, so that the precision evaluation of the tilt compensation is realized.
(1) The invention implements a factory calibration link, compensates the system zero offset and the proportionality coefficient of the inertial sensor, and improves the precision of the observed value of the inertial sensor; the mounting error of the inertial sensor is calibrated, and the influence of the mounting error on the inclination measurement precision is avoided, because the three-dimensional posture of the receiver represents the conversion relation between the inertial sensor and a navigation coordinate system, if the inertial sensor is not parallel to the bottom surface of the GNSS receiver, the vector decomposition error of the centering rod can be caused, and finally the inclination compensation error can be caused;
(2) the invention adopts a GNSS/MEMS data synchronization technology based on PPS (pulse per second) pulse signals, the time service precision of the PPS pulse signals is nanosecond and is a main reference of a time synchronization scheme, because the GNSS receiver needs processing time from receiving satellite electromagnetic wave signals to outputting position and speed information, the processing time of the current mainstream GNSS receiver is 10-100ms, and the three-dimensional attitude information is resolved according to high-frequency inertial data above 100Hz, the attitude corresponding to the moment of outputting position information by the GNSS receiver is not the attitude corresponding to the moment of receiving the electromagnetic wave signals by the GNSS receiver, therefore, the invention utilizes the PPS pulse signals to stamp the inertial observation data by a time system which is the same as the GNSS position, thereby matching the attitude which is closest to the GNSS position, and ensuring the dynamic property and the real-time property of inclination measurement;
(3) the method fully utilizes the speed and position information of the GNSS to realize the state initialization of the GNSS/MEMS fusion calculation, only a surveyor needs to hold the GNSS receiver by hand to walk for about 10m, the initialization of the GNSS/MEMS fusion calculation state can be completed according to the speed and the position of the GNSS receiver, the key is the initialization of the three-dimensional attitude, and once the state initialization is completed, the fusion calculation process can be entered;
(4) the method adopts a GNSS/MEMS fusion algorithm to track and solve the three-dimensional attitude, integrates the calculation result and the GNSS solution result of the inertia mechanical arrangement through a Kalman filter, estimates the attitude error, the speed error and the position error of the mechanical arrangement and the residual zero offset error of an inertia sensor, and performs feedback correction, thereby realizing the high-frequency and high-precision dynamic tracking and solving of the three-dimensional attitude, and fundamentally avoiding the problems of correction of a magnetometer and poor reliability caused by electromagnetic environment interference because the magnetometer is not used; because the motion state is completely modeled, the tracking of the three-dimensional attitude cannot be influenced by the change of the motion state of the GNSS receiver, so the method can realize dynamic inclination measurement without being carried out under a quasi-static condition;
(5) the invention calculates the inclination direction and the inclination angle of the centering rod relative to the local horizontal coordinate system according to the three-dimensional attitude of the GNSS receiver so as to intuitively display the space positions of the GNSS receiver and the centering rod on the display;
(6) the method deduces the real-time standard deviation of the three-dimensional attitude according to the simplified error model arranged by the inertia machine, and then deduces the standard deviation of the tilt compensation point and the standard deviation of the tilt measurement angle according to the error propagation law, thereby visually displaying the precision level of the tilt measurement and improving the experience of users of the tilt measurement;
the following provides specific embodiments of the present invention
Referring to fig. 3b, the GNSS receiver 1 includes an antenna for receiving a satellite electromagnetic wave signal and a board card for performing GNSS navigation positioning calculation, and is configured to implement GNSS navigation positioning calculation and output GNSS original observation data, a PPS pulse signal, and antenna phase center speed and position information; the IMU inertia measurement module 2 is arranged at the center of the GNSS receiver and is used for measuring the linear velocity and the angular velocity of the IMU in three orthogonal directions so as to perform inertia mechanical arrangement and calculation; the CPU 3 mainly realizes the time synchronization of GNSS navigation positioning information and IMU inertial observation data, the IMU inertial mechanical arrangement and calculation, the GNSS/INS data fusion calculation and the operation of algorithms such as the inclination compensation of space vectors and the like; the physical medium is transmitted by the centering rod 4 and the space position between the GNSS antenna phase center position and the measuring point;
the GNSS/INS data fusion algorithm mainly comprises three parts: the GNSS/INS data time synchronization, the GNSS/INS data fusion calculation and the space compensation calculation exist in a logical sequence.
Referring to fig. 4a and 4b, the horizontal table is used for providing a reference horizontal plane, and can also be provided by using equipment such as a turntable or an index head, the interior of the regular hexahedron is hollow, the horizontal table is used for providing planes which are orthogonal to each other, and a vertical plane is formed by the horizontal plane, and can also be realized by using equipment such as a turntable or an index head.
Referring to fig. 5, a PPS pulse signal is a nanosecond pulse signal, which is a reference signal of the data synchronization scheme of the present invention, an output frequency of a GNSS navigation positioning result is 1Hz, 5Hz, or 10Hz, a GPS time system is used, a positioning result is a measurement result based on the whole second time of GPS time, and a PPS pulse is triggered based on the whole second time of the GPS time system, so that a PPS pulse triggering time strictly corresponds to a measurement time of a GNSS receiver on a time system, but since the GNSS receiver needs to analyze, resolve, and output observation data, a time at which the GNSS receiver outputs a navigation positioning result is not consistent with an actual measurement time, there is a delay, an update frequency of IMU observation data is in a kilohz level, real-time is high, and data fusion resolving needs to fuse the navigation positioning results that are consistent with space, so that time systems of the IMU and the GNSS need to be unified, the GNSS/INS time synchronization scheme provided by the invention takes PPS second pulse signals as synchronization reference, carries out time marking on high-frequency IMU observation data by a GPS time system in a real-time observation data time sequence, and synchronizes the observation data of the IMU to the GPS time system, thereby realizing time matching of inertial navigation positioning results and observation data with GNSS navigation positioning results and observation data.
The algorithm principle of the tilt measurement scheme in the present invention is briefly described as follows:
the first step is as follows: calibrating the whole GNSS receiver before leaving factory:
the calibration link and the algorithm resolving link relate to the definition of a coordinate system, mainly the definition of a carrier system and a navigation system, and are uniformly explained herein, the carrier system is an orthogonal rectangular coordinate system fixedly connected with an IMU module in a GNSS receiver, the IMU centroid is taken as an origin to describe the three-dimensional space definition of the IMU module, the carrier system can be divided into the definitions of upper right front, upper front left, upper front right, lower right and the like according to the direction of a coordinate axis, only right-hand rules are required to be met, the navigation system uses a space coordinate system for describing a navigation positioning result, and mainly comprises an ECEF ground center ground fixed coordinate system, a geographic system, an ENU/NED local horizontal coordinate system and the like, only the upper right front coordinate system and the ENU coordinate system are selected to describe the carrier system and the navigation system, so as to explain the method and the algorithm adopted by the invention, and other coordinate definitions do not influence the use of the method and the algorithm adopted by the invention.
According to the attached drawing 4a, the bottom surface of the GNSS receiver is fixedly connected with the bottom surface inside the hexahedron through a connecting piece, the hexahedron is placed on a horizontal table in sequence according to the direction of a coordinate system shown in the attached drawing 4b, static data are collected respectively, 6 groups of data are collected totally, the placing sequence can be not according to the sequence shown in the attached drawing 4b, only coordinate axis pointing correspondence is needed, the pointing direction of XYZ can be redefined, and only right-hand rule is needed to be met and the pointing direction correspondence of XYZ pointing backward can be redefined with the attached drawing 4 b. The method comprises the steps of establishing a least square model (formula 3) according to an IMU observation model shown in formula 1, and estimating an accelerometer zero offset, a gyroscope zero offset and an accelerometer proportionality coefficient of the IMU by taking theoretical output of the IMU on a horizontal plane as constraint, wherein an observation value of the accelerometer in a vertical upward direction is theoretically the magnitude of local gravity, an observation value of the accelerometer in a horizontal direction is theoretically 0, and the gyroscope is theoretically sensitive to the earth self-propagation angular velocity.
For the gyroscope, the calibration scheme adopted by the invention only calibrates the zero offset term of the gyroscope, and the calculation method is to respectively add the average values of the outputs corresponding to the XYZ axes in the 6 groups of sequences and then calculate the average, for example, formula 2 calculates the X-axis zero offset of the gyroscope, namely the zero offset compensation term bias of the gyroscope.
For the accelerometer, the zero offset term and the proportional coefficient term of the accelerometer are estimated by using the least square algorithm with the theoretical output of a horizontal plane as constraint, 3 zero offset coefficients and 9 proportional coefficients are required to be estimated according to an error model of the accelerometer in formula 1, and 12 variables are required.
Compensating the observation data of the static accelerometer corresponding to the position No. 1, No. 2 or No. 3 in the figure 4b according to the formula 1 by using the accelerometer zero offset and the proportionality coefficient calculated by the formula 3, and calculating the horizontal installation error according to the following formula by using the compensated data:
wherein accx, accy and accz are average values of triaxial outputs of the accelerometer after compensation,
the formula is an algorithm for defining and calculating horizontal installation errors pitch and roll according to the coordinate system selected by the formula, and the derivation of the horizontal installation errors is defined and calculated by other coordinate systemsThe process is similar.
The second step is that: GNSS/INS data synchronization:
as shown in fig. 5, after the IMU inertial sensor and the GNSS board card complete the startup initialization, the inertial measurement data of the IMU, the observation data of the GNSS receiver, and the PPS second pulse signal are accessed to the CPU processor, the CPU system time stamp is performed on the IMU observation value by the crystal oscillator of the CPU, when the PPS signal is triggered, the whole second part of the GPS system is assigned to the timestamp of the IMU observation value, and the decimal part of the IMU observation value timestamp is set to zero, when the PPS signal is not triggered, the crystal oscillator with the CPU maintains the accumulation and the whole second carry of the decimal part of the IMU observation value timestamp, and then the synchronized GNSS observation data and IMU observation data are transmitted to the GNSS/INS fusion calculation algorithm module.
The third step: initializing a navigation resolving state:
the invention relates to an inertial mechanical arrangement algorithm, belonging to dead reckoning algorithm, requiring initial values of position, speed and attitude of a carrier, the invention fully utilizes the speed and position information of GNSS to realize the initialization of the inertial mechanical arrangement, only a surveyor holds a GNSS receiver to walk for about 10m in a straight line, the walking speed is more than 1m/s, as shown in figure 6, the initialization of the position, speed and attitude of the inertial mechanical arrangement can be completed according to the position and speed information output by the GNSS receiver, because the GNSS observation data and the IMU observation data are synchronized in time, the initialization of the inertial mechanical arrangement through the GNSS observation data has no problem of inconsistent time and space;
the fourth step: GNSS/INS data fusion resolving:
after the initialization of the position, velocity and attitude is completed, dead reckoning can be performed at a frequency not higher than the sampling frequency of the inertial observation data of the IMU according to the differential equation (equations 4-1,2,3) of the inertial mechanical programming algorithm, and a state equation (equation 6) of the GNSS/INS data fusion solver kalman filter can be constructed according to the error equation (equations 5-1-9) of the differential equation of the inertial mechanical programming algorithm (since the carrier system and the navigation system are selected differently, equations 4,5,6 have differences caused by the transformation of the coordinate system, the en is used as the carrier system, the local horizontal coordinate system is used as the navigation system to give a specific equation, and the equations defined by other coordinate systems are similar), and the time update of the kalman filter is performed at a frequency not higher than the sampling frequency of the inertial observation data of the IMU (equations 7-1,2), once the CPU receives the GNSS navigation positioning result corresponding to the observation time, and performing measurement updating of the Kalman filter (formulas 7-3,4 and 5), feeding back and correcting the state error estimated by the measurement updating to the position, speed and attitude calculated by the inertial mechanical arrangement, outputting the corrected position, speed and attitude as the result of GSNN/INS fusion calculation, and completing one-time GNSS/INS data fusion calculation, wherein the GNSS/INS data fusion algorithm circularly executes the processes to realize the dynamic high-precision tracking of the three-dimensional attitude, speed and position.
wherein ,
representing the rotation of the navigation system relative to the inertial system, it comprises two parts: rotation of the navigation system due to rotation of the earth, and movement of the system near the surface of the earth due to bending of the surface of the earth, i.e.
wherein
ωieL and h are the geographic latitude and altitude, respectively, for the earth rotation angular rate.
wherein 
For the specific force measured by the accelerometer,
for coriolis accelerations caused by carrier motion and earth rotation,
for centripetal acceleration to the ground, g, caused by movement of the carriernIn order to be the acceleration of the gravity,
collectively referred to as detrimental acceleration.
wherein
RMh＝RM+h，RNh＝RN+h
The right side of the equations 5-1 through 5-9 constitutes the state space X in equation 6kAnd the zero offset error terms of the IMU accelerometer and gyroscope are extended, the left side of the equations 5-1 to 5-9 form the state transition matrix phi in equation 6k/k-1And extending the state transfer term of zero offset error, W, of IMU accelerometers and gyroscopesK-1For state-transfer noise, set according to nominal accuracy and empirical values of the inertial sensor, ZkIn order to observe the quantity, the invention adopts the difference value of the GNSS speed and position and the position and speed of inertial dead reckoning as the observed quantity HkFor the measurement matrix, v is set according to the transformation relation between the observed quantity and the state spacekFor measuring the noise, the positioning and speed-fixing accuracy of the GNSS is set.
State one-step prediction
State one-step prediction mean square error
Filter gain
State estimation
State estimation mean square error
Pk＝(I-KkHk)Pk/k-1 (7-5)
The fifth step: and (3) inclination measurement:
the projection of the distance L from the bottom of the centering rod to the phase center of the antenna under the carrier coordinate system ENU is a constant three-dimensional space vector leverb＝[0 0 -L]The three-dimensional attitude output by the GNSS/INS data fusion algorithm describes the rotation relationship between a carrier system b (ENU) and a navigation system n (a local horizontal coordinate system), and a direction cosine matrix can be constructed according to the three-dimensional attitude
Projecting the three-dimensional space vector under the carrier system to the three-dimensional space vector under the navigation coordinate system
Thereby leading the antenna phase center position R under the navigation coordinate systemantennaConverting the position R of the measuring point at the bottom of the centering rod in a navigation coordinate systemmeasurementAnd realizing inclination measurement.
And a sixth step: evaluation index of inclination measurement precision:
the three-dimensional attitude calculation error in a short time can be evaluated by simplifying the inertia mechanical layout error equation (formula 9) and approximating the equation on the basis of formulas 5-1 to 5-9, the standard deviation of the three-dimensional attitude is calculated, and the standard deviation of the inclination measurement point position and the standard deviation of the inclination angle are calculated by formula 8 and formula 10 on the basis of the three-dimensional attitude standard deviation according to the error propagation law.
wherein φE,φN,φUIs the attitude standard deviation phi of three axial directions of the ENUE,φN,φUIs the initial standard deviation of attitude, εE,εN,εUFor zero bias of the ENU tri-axial gyroscope,
is zero offset of ENU triaxial accelerometer, R is earth radius, delta vE0,δvN0Is the standard deviation of the velocities in the E and N directions, tLL is the geographical latitude, and t is the inertial dead reckoning time.
The seventh step: description of the spatial state of the centering rod:
deducing the inclination angle and the inclination direction of the centering rod in a navigation coordinate system according to the three-dimensional posture so as to conveniently describe the inclination state of the centering rod at a display end, and setting a direction cosine matrix from a carrier system b to a navigation system n
The inclination direction angle dir and the inclination angle tilt of the centering rod can be calculated by the following formulas:
(1) the invention implements a factory calibration link, compensates the system zero offset and the proportionality coefficient of the inertial sensor, and improves the precision of the observed value of the inertial sensor; the mounting error of the inertial sensor is calibrated, and the influence of the mounting error on the inclination measurement precision is avoided, because the three-dimensional posture of the receiver represents the conversion relation between the inertial sensor and a navigation coordinate system, if the inertial sensor is not parallel to the bottom surface of the GNSS receiver, the vector decomposition error of the centering rod can be caused, and finally the inclination compensation error can be caused;
(2) the invention adopts a GNSS/MEMS data synchronization technology based on PPS (pulse per second) pulse signals, the time service precision of the PPS pulse signals is nanosecond and is a main reference of a time synchronization scheme, because the GNSS receiver needs processing time from receiving satellite electromagnetic wave signals to outputting position and speed information, the processing time of the current mainstream GNSS receiver is 10-100ms, and the three-dimensional attitude information is resolved according to high-frequency inertial data above 100Hz, the attitude corresponding to the moment of outputting position information by the GNSS receiver is not the attitude corresponding to the moment of receiving the electromagnetic wave signals by the GNSS receiver, therefore, the invention utilizes the PPS pulse signals to stamp the inertial observation data by a time system which is the same as the GNSS position, thereby matching the attitude which is closest to the GNSS position, and ensuring the dynamic property and the real-time property of inclination measurement;
(3) the method fully utilizes the speed and position information of the GNSS to realize the state initialization of the GNSS/MEMS fusion calculation, only a surveyor needs to hold the GNSS receiver by hand to walk for about 10m, the initialization of the GNSS/MEMS fusion calculation state can be completed according to the speed and the position of the GNSS receiver, the key is the initialization of the three-dimensional attitude, and once the state initialization is completed, the fusion calculation process can be entered;
(4) the method adopts a GNSS/MEMS fusion algorithm to track and solve the three-dimensional attitude, integrates the calculation result and the GNSS solution result of the inertia mechanical arrangement through a Kalman filter, estimates the attitude error, the speed error and the position error of the mechanical arrangement and the residual zero offset error of an inertia sensor, and performs feedback correction, thereby realizing the high-frequency and high-precision dynamic tracking and solving of the three-dimensional attitude, and fundamentally avoiding the problems of correction of a magnetometer and poor reliability caused by electromagnetic environment interference because the magnetometer is not used; because the motion state is completely modeled, the tracking of the three-dimensional attitude cannot be influenced by the change of the motion state of the GNSS receiver, so the method can realize dynamic inclination measurement without being carried out under a quasi-static condition;
(5) the invention calculates the inclination direction and the inclination angle of the centering rod relative to the local horizontal coordinate system according to the three-dimensional attitude of the GNSS receiver so as to intuitively display the space positions of the GNSS receiver and the centering rod on the display;
(6) the method deduces the real-time standard deviation of the three-dimensional attitude according to the simplified error model arranged by the inertia machine, and then deduces the standard deviation of the tilt compensation point and the standard deviation of the tilt measurement angle according to the error propagation law, thereby intuitively displaying the precision level of the tilt measurement and improving the experience of users of the tilt measurement.
The above description is of the preferred embodiment of the invention. It is to be understood that the invention is not limited to the particular embodiments described above, in that devices and structures not described in detail are understood to be implemented in a manner common in the art; those skilled in the art can make many possible variations and modifications to the disclosed embodiments, or modify equivalent embodiments to equivalent variations, without departing from the spirit of the invention, using the methods and techniques disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are still within the scope of the protection of the technical solution of the present invention, unless the contents of the technical solution of the present invention are departed.
Claims (6)
1. A novel GNSS receiver inclination measuring method is characterized by comprising the following steps:
step (1): factory correction;
step (2): time synchronization;
and (3): initializing a state;
and (4): GNSS/MEMS fusion resolving;
and (5): tilt compensation;
and (6): displaying the inclined state;
and (7): and (5) evaluating the inclination precision.
2. The novel GNSS receiver inclination measurement method of claim 1, wherein the step (2) specifically includes: the time synchronization of GNSS data and IMU data is realized based on the PPS pulse signal of the GNSS receiver, so that the real-time performance and the dynamic performance of inclination measurement are ensured.
3. The novel GNSS receiver inclination measurement method of claim 1, wherein the step (3) specifically includes: and the initialization of the position, the speed and the attitude is completed by utilizing the position and the speed information of the GNSS, so that an initial state is provided for the GNSS/MEMS fusion solution.
4. The novel GNSS receiver inclination measurement method of claim 1, wherein the step (4) specifically includes: and (3) constructing a kinematic equation of a Kalman filter on the basis of an error equation arranged by an inertial machine, and taking the position and speed information of the GNSS as measurement input, thereby realizing the data fusion resolving and the real-time estimation of the position, the speed and the attitude of the GNSS/MENS.
5. The novel GNSS receiver inclination measurement method of claim 1, wherein the step (5) specifically includes: decomposing the constant centering rod vector under the carrier coordinate system to a navigation system on the basis of the three-dimensional attitude, and performing centering rod length compensation on the antenna phase center position under the navigation system so as to obtain the position of the measuring point under the navigation system.
6. The novel GNSS receiver inclination measurement method of claim 1, wherein the step (6) specifically includes: the calculation of the inclination angle and the inclination direction of the centering rod is realized on the basis of the three-dimensional attitude information, so that the description of the inclination state of the centering rod is facilitated; the step (7) specifically comprises: and deducing the standard deviation of the position of the compensation point according to the error propagation law by using the three-dimensional attitude standard deviation estimated by the GNSS/MEMS fusion algorithm, thereby realizing the precision evaluation of the tilt compensation.
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| EP3891523A1 (en) * | 2018-12-03 | 2021-10-13 | Lac Camera Systems OY | Self-positioning method, self-positioning system and tracking beacon unit |
| CN109814133A (en) * | 2019-03-07 | 2019-05-28 | 上海华测导航技术股份有限公司 | GNSS receiver inclinometric system, method, apparatus and storage medium |
| CN110017849B (en) * | 2019-04-18 | 2020-12-22 | 菲曼(北京)科技有限公司 | Inclination measurement method of surveying and mapping all-in-one machine based on GNSS receiver and IMU sensor |
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| CN112729280B (en) * | 2020-12-10 | 2022-09-13 | 山东省科学院海洋仪器仪表研究所 | Polyhedral array structure-based micro-inertia attitude measurement device and method |
| CN112965091B (en) * | 2021-02-02 | 2022-07-12 | 山东理工大学 | Agricultural robot positioning method and system |
| CN114167493B (en) * | 2021-11-23 | 2023-08-04 | 武汉大学 | Seismic rotation measurement system and method of GNSS double-antenna auxiliary gyroscope |
| CN114264302B (en) * | 2021-12-14 | 2024-01-30 | 新纳传感***有限公司 | Inclination measuring device and method for initializing inertial navigation system thereof |
| CN115468485B (en) * | 2022-11-15 | 2023-03-10 | 国仪量子(合肥)技术有限公司 | Method for calculating tool face angle and storage medium |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20120086598A1 (en) * | 2010-10-08 | 2012-04-12 | Canadian Space Agency | Apparatus and methods for driftless attitude determination and reliable localization of vehicles |
| CN103926608A (en) * | 2014-04-18 | 2014-07-16 | 广州南方卫星导航仪器有限公司 | Incline compensation method of GNSS measuring device |
| CN104501775A (en) * | 2014-12-10 | 2015-04-08 | 深圳市华颖泰科电子技术有限公司 | Surveying and mapping integrated machine and declivity surveying method thereof |
| CN104635247A (en) * | 2015-03-03 | 2015-05-20 | 上海华测导航技术股份有限公司 | GNSS (global navigation satellite system) automatic measuring system and GNSS automatic measuring method based on acceleration sensor |
| CN104776835A (en) * | 2015-03-20 | 2015-07-15 | 深圳市华颖泰科电子技术有限公司 | Surveying and mapping all-in-one (AIO) machine compensation device, compensation system, and compensation method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2722647A1 (en) * | 2012-10-18 | 2014-04-23 | Leica Geosystems AG | Surveying System and Method |
| CN105190238B (en) * | 2013-01-23 | 2019-01-08 | 可信定位股份有限公司 | Method and apparatus for improving navigation of riding |
| US9441974B2 (en) * | 2013-03-15 | 2016-09-13 | Novatel Inc. | System and method for calculating lever arm values photogrammetrically |
-
2018
- 2018-11-09 CN CN202110426468.7A patent/CN113091709B/en active Active
- 2018-11-09 CN CN201811333054.4A patent/CN109269471B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20120086598A1 (en) * | 2010-10-08 | 2012-04-12 | Canadian Space Agency | Apparatus and methods for driftless attitude determination and reliable localization of vehicles |
| CN103926608A (en) * | 2014-04-18 | 2014-07-16 | 广州南方卫星导航仪器有限公司 | Incline compensation method of GNSS measuring device |
| CN104501775A (en) * | 2014-12-10 | 2015-04-08 | 深圳市华颖泰科电子技术有限公司 | Surveying and mapping integrated machine and declivity surveying method thereof |
| CN104635247A (en) * | 2015-03-03 | 2015-05-20 | 上海华测导航技术股份有限公司 | GNSS (global navigation satellite system) automatic measuring system and GNSS automatic measuring method based on acceleration sensor |
| CN104776835A (en) * | 2015-03-20 | 2015-07-15 | 深圳市华颖泰科电子技术有限公司 | Surveying and mapping all-in-one (AIO) machine compensation device, compensation system, and compensation method |
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