Position calculation method and position calculation system

Abstract

To provide a position calculation method and a position calculation system, which easily calculate a measurement position with high accuracy of a millimeter level.SOLUTION: A position calculation method according to the present disclosure, calculates position information for measurement stations G1, G2, G3, ..., GN on the basis of signals from a plurality of satellites 5a, and calculates position information for points S1, S2, S3, ..., SL on the basis of signals relating to remote sensing, and corrects the position information for at least one measurement point on the basis of a base line constructed by connecting between the different two measurement points of the two or more measurement points composed of the measurement stations G1, G2, G3, ..., GN and the points S1, S2, S3, ..., SL. The base line includes line segments constructed by connecting between the measurement stations G1, G2, G3, ..., GN and the points S1, S2, S3, ..., SL.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a position calculation method and a position calculation system. [Background technology]

[0002] Conventionally, a position calculation method is described in Patent Document 1. This position calculation method is a method for measuring position information of measurement points using a Global Positioning System (GPS), in which at least three measurement points and aerial measurement points are set above the measurement points, and position information of the measurement points and aerial measurement points is calculated using signals from multiple GPS satellites.

[0003] Then, based on the calculated position information, a three-dimensional triangular network is constructed with the measurement points and aerial measurement points as vertices, and the position information of the measurement points and aerial measurement points is adjusted by network averaging calculation. This calculation method performs network averaging calculation using the position information of aerial measurement points above the measurement points, so vertical displacements such as ground displacement can be calculated with high accuracy. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2002-250624 A Summary of the Invention [Problem to be solved by the invention]

[0005] In position calculation methods using GNSS (Global Navigation Satellite System) such as GPS, it is important to remove noise contained in the radio waves from positioning satellites. Possible noise sources include atmospheric effects, clock errors, and the surrounding environment. By using PPP (Precise Point Positioning) and RTK (Real-Time Kinematic) technology that uses carrier phase, atmospheric and clock errors can be effectively removed, allowing for highly accurate position measurement.

[0006] However, even the most accurate RTK technology has a positioning accuracy of a few centimeters in real time, making it difficult to calculate the measured position with high accuracy when it comes to monitoring buildings and infrastructure, which requires millimeter-level accuracy.

[0007] Therefore, an object of the present disclosure is to provide a position measuring device and a position measuring system that can easily calculate a measurement position with high accuracy on the millimeter level. [Means for solving the problem]

[0008] The position calculation method disclosed herein calculates position information of a measurement station based on signals from multiple satellites, and calculates position information of a point based on signals related to remote sensing, and corrects the position information of at least one of the measurement points based on a baseline constructed by connecting two different measurement points among two or more measurement points consisting of the measurement station and the point, and the baseline includes a line segment constructed by connecting the measurement station and the point.

[0009] According to the present disclosure, in addition to the calculated positions of the measurement stations calculated based on signals from multiple satellites, the calculated positions of the points calculated based on signals related to remote sensing are also used to perform baseline analysis. Therefore, since the number of measurement points can be increased without placing new measurement stations, the position of at least one measurement point can be calculated with high accuracy compared to a case where the position of at least one measurement point is precisely determined using only the calculated positions of the measurement stations. Therefore, the measurement position of at least one measurement point can be calculated with high accuracy at the millimeter level.

[0010] In addition, position information of the multiple measurement stations may be calculated using signals from the multiple satellites, and position information of the multiple points may be calculated using a remote sensing technique, multiple baselines may be constructed by connecting two different measurement points among the multiple measurement points consisting of the multiple measurement stations and the multiple points, multiple different ring closures may be constructed using the multiple baselines, and the position of at least one measurement point may be corrected based on the ring closure difference among the multiple ring closures.

[0011] According to this configuration, the loop closure is constructed using the calculated positions of multiple measurement stations calculated based on signals from multiple satellites and the calculated positions of multiple points calculated based on signals related to remote sensing, so it is easy to increase the number of loop closures, and therefore it is easy to calculate the measurement position of at least one measurement point with millimeter-level high accuracy.

[0012] In addition, the position of the measurement point may be represented by a four-dimensional coordinate position consisting of a one-dimensional position based on the time when the measurement of the measurement point was performed and a three-dimensional spatial position measured with respect to the measurement point, and the baseline may be a line segment connecting two points in the four-dimensional coordinate system.

[0013] In a method of performing network averaging based on location information at a single time for each of multiple points, even if the most accurate RTK technology is used, it is not easy to calculate the measurement position with high accuracy if the measurement position changes suddenly in a short period of time due to crustal movement, etc.

[0014] In contrast, according to the present configuration, since each baseline includes information on the measurement time of the measurement point, it is easy to correct the change in the measurement position of the measurement point over time. And, for example, even if the measurement position changes suddenly in a short period of time due to crustal movement, the measurement error can be reduced, and as a result, the measurement position of the measurement point can be calculated with high accuracy.

[0015] In addition, the position calculation system of the present disclosure includes a first calculation unit that calculates position information of a measurement station based on signals from multiple satellites, a second calculation unit that calculates position information of a point based on a signal related to remote sensing, and a correction unit that corrects the position information of at least one of the measurement points based on a baseline constructed by connecting two different measurement points among two or more measurement points consisting of the measurement station and the point, and the baseline includes a line segment constructed by connecting the measurement station and the point.

[0016] According to the present disclosure, in addition to the calculated position of the measurement station calculated by the first calculation unit based on signals from multiple satellites, the calculated position of the point calculated by the second calculation unit based on signals related to remote sensing is also used to perform baseline analysis. Therefore, it is possible to increase the number of measurement points without placing new measurement stations. Therefore, it is easy for the correction unit to correct the position of at least one measurement point with high accuracy and to calculate the measurement position of at least one measurement point with high accuracy at the millimeter level.

[0017] In addition, the first calculation unit may calculate position information of the multiple measurement stations using signals from the multiple satellites, and the second calculation unit may calculate position information of the multiple points using the remote sensing technique, and the correction unit may construct multiple baselines by connecting two different measurement points among the multiple measurement points consisting of the multiple measurement stations and the multiple points, and then construct multiple ring closures that are different from each other using the multiple baselines, and the correction unit may correct the position of at least one measurement point based on the ring closure difference among the multiple ring closures.

[0018] According to this configuration, since the loop closure is constructed using the calculated positions of the multiple measurement stations calculated by the first calculation unit based on signals from multiple satellites and the calculated positions of the multiple points calculated by the second calculation unit based on signals related to remote sensing, it is easy to increase the number of loop closures. Therefore, it is easy for the correction unit to correct the measurement position of at least one measurement point with high accuracy at the millimeter level. Effect of the Invention

[0019] According to the position calculation method and position calculation system disclosed herein, it is easy to calculate a measurement position with high accuracy on the millimeter level. [Brief description of the drawings]

[0020] [Figure 1] 1 is a schematic configuration diagram of a positioning satellite system that performs position calculation according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a block diagram showing a main configuration of a position calculation device. [Diagram 3] FIG. 11 is a diagram showing a procedure in which the position calculation device displays and outputs the three-dimensional coordinates of one measurement point. [Figure 4] FIG. 13 is a schematic configuration diagram of a modified positioning satellite system. [Diagram 5] FIG. 13 is a block diagram showing a main configuration of a position calculation device according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, when multiple embodiments or modified examples are included below, it is assumed from the beginning that new embodiments will be constructed by appropriately combining the characteristic parts of them. In addition, in the following examples, the same components are given the same symbols in the drawings, and duplicated explanations are omitted. In addition, among the components described below, components that are not described in the independent claims showing the highest concept are optional components and are not essential components.

[0022] 1 is a schematic diagram of a positioning satellite system 1 that performs position calculation according to an embodiment of the present disclosure. The positioning satellite system 1 includes a fixed station K that receives GNSS signals from four or more first satellites 5a used in GNSS, such as GPS (Global Positioning System), QZSS (Quasi-Zenith Satellite System), GLONASS (Global Navigation Satellite System), Galileo, etc., a measurement station G that receives GNSS signals from the four or more first satellites 5a, and a measurement station H that receives GNSS signals from the four or more first satellites 5a. 1 ,G 2 ,G 3 G N (N is any natural number), a second satellite 5b equipped with a synthetic aperture radar (SAR) sensor (hereinafter, simply referred to as a SAR sensor), and a position calculation device I. The position calculation device I is, for example, configured with a server located on a cloud of a network. 1 ,G 2 ,G 3 G N , the SAR sensor, and the position calculation device I constitute a position calculation system 50.

[0023] The positioning satellite system 1 includes four or more first satellites 5a, a fixed station K, and a measurement station G 1 ,G 2 ,G 3 G N , and position calculation device I, RTK (Real Time Kinematic) technology is used to calculate G 1 ,G 2 ,G 3 G N By using RTK, the location of the measurement station G can be determined for each measurement. 1 ,G 2 ,G 3 G N The location of the object can be pinpointed with high accuracy, within an error range of a few centimeters.

[0024] The fixed station K is installed on the ground. The fixed station K receives four or more GNSS signals from four or more first satellites 5a and transmits the four or more GNSS signals to the position calculation device I. In addition, each measurement station G 1 ,G 2 ,G 3 G N The position calculation device I receives GNSS signals from four or more first satellites 5a and transmits the received four or more GNSS signals to the position calculation device I. 1 ,G 2 ,G 3 G N The location of the satellite is calculated based on four or more GNSS signals received from fixed station K and each measurement station G. 1 ,G 2 ,G 3 G N The position calculation device I calculates the position based on the RTK technology using four or more GNSS signals received from each measurement station G. 1 ,G 2 ,G 3 G N Its location is calculated based on eight or more GNSS signals.

[0025] Furthermore, the position calculation device I performs interferometric SAR analysis based on the signal from the SAR sensor of the second satellite 5b to determine the position S 1 ,S 2 ,S 3 ···S L (L is a natural number) to determine the location of the object. More specifically, the SAE sensor receives radio waves (microwaves) that are emitted from the SAE sensor and reflected off the Earth's surface. Interferometric SAR is a technology that uses the "phase" of radio waves to obtain images, and the phase of the reflected radio waves (hereafter referred to as the reflected waves) contains information about the distance from the antenna to the Earth's surface.

[0026] With interferometric SAR technology, two SAR observations are performed on the same location on the earth's surface to prepare two "phase images," which are then interfered with to obtain the difference (interferometric analysis), making it possible to obtain information on slight distance differences and capture changes in the ground. Whereas distance measurements using conventional radar technology alone have an accuracy of only a few meters, interferometric SAR makes it possible to measure at the centimeter level.

[0027] SAR can visualize the strength of the waves reflected from the Earth's surface, that is, the "intensity" of the reflected waves, in black and white. Areas with lower intensity appear blacker, while areas with higher intensity appear whiter. For example, large concrete buildings reflect radio waves well toward the satellite, so they appear whitish, while the ocean reflects almost no radio waves toward the satellite, so they appear black. In this way, the strength of the reflected waves changes depending on the topography and the condition of the Earth's surface.

[0028] In the image, there are points called PS (Persistent Scatterer) points where the reflected radio waves are stable and appear white over time, and where the observation error is small (such as artificial structures). 1 ,S 2 ,S 3 ···S L is such a PS point. By using the PS points as measurement points for measuring the position with the interferometric SAR technique, the measurement error in the interferometric SAR technique can be further reduced.

[0029] 1, N=3 and L=7 (the number of measurement stations is 3 and the number of points (PS points) is 7), and the number of points (PS points) is greater than the number of measurement stations. However, the number of measurement stations may be the same as the number of points (PS points), or may be greater than the number of points (PS points).

[0030] Fig. 2 is a block diagram showing the main configuration of the position calculation device I. As shown in Fig. 2, the position calculation device I includes a receiving unit 6, a display unit 7, an output unit 8, an input unit 9, and a control device 10. The receiving unit 6 may be configured as a known wireless receiving device, and in the case where the position calculation device I receives a signal via a network, the receiving unit 6 is configured as an interface for receiving data from an external device via the network.

[0031] The display unit 7 is composed of a liquid crystal panel, an organic EL panel, or the like, and displays, for example, the position of the calculated measurement point on three-dimensional spatial coordinates (hereinafter simply referred to as three-dimensional coordinates) described below. The output unit 8 is composed of a printer, and prints out information on the calculated three-dimensional coordinate position of the measurement point. The position calculation device I does not necessarily have to have the display unit 7 or the output unit 8.

[0032] The control device 10 is preferably configured by a computer, for example, a microcomputer, and includes a control unit 11 and a storage unit 12. The control unit 11, i.e., a processor, includes, for example, a CPU (Central Processing Unit). The storage unit 12 includes an HDD (Hard Disk Drive), an SSD (Solid State Drive), an eMMC (embedded Multi Media Card), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The CPU reads out and executes programs and the like previously stored in the storage unit 12. A non-volatile memory such as a ROM (Read Only Memory) previously stores a control program, a predetermined threshold value, and the like. A volatile memory such as a RAM (Random Access Memory) temporarily stores the read program and processing data.

[0033] The control unit 11 includes a first calculation unit 11a, a second calculation unit 11b, a loop closure construction unit 11c, and a net average calculation unit 11d. The operations of the first calculation unit 11a, the second calculation unit 11b, the loop closure construction unit 11c, and the net average calculation unit 11d will be described in detail below with reference to Fig. 3. Fig. 3 is a diagram showing a procedure in which the position calculation device I displays and outputs precise three-dimensional coordinates of one measurement point (position-specific point).

[0034] 3, first, in step S1, the first calculation unit 11a calculates the number of measurement stations G 1 ,G 2 ,G 3 G N The tentative location of is determined by four GNSS signals from fixed station K and each measurement station G. 1 ,G 2 ,G 3 G N The first calculation unit 11a calculates the distance between the measurement point G 1 ,G 2 ,G 3 G N The three-dimensional coordinate values ​​are temporarily stored in the storage unit 12.

[0035] Next, in step S2, the second calculation unit 11b calculates the points S 1 ,S 2 ,S 3 ···S L The second calculation unit 11b calculates the tentative location of each point S based on signals based on two SAR observations in the interferometric SAR technique. 1 ,S 2 ,S 3 ···S L The three-dimensional coordinate values ​​are temporarily stored in the storage unit 12. Note that there may be a period during which steps S1 and S2 are performed simultaneously, or step S2 may be performed before step S1.

[0036] Next, in the next calculation, a triangular mesh is selectively constructed. First, in step S3, the loop closure construction unit 11c identifies the three-dimensional coordinate in one measurement (hereinafter referred to as a position-specific point) for which precise three-dimensional coordinates are to be calculated from the values ​​of multiple three-dimensional coordinates in each measurement of each measurement point based on information from the input unit 9. Next, in step S4, the loop closure construction unit 11c selectively constructs multiple three-dimensional triangular meshes that can precisely determine the three-dimensional coordinate position of the position-specific point.

[0037] A triangulation network is a set of triangles in four-dimensional coordinates that are constructed by connecting the measurement points with each other by straight lines. Each triangulation network is also composed of three baselines, and each baseline is connected to multiple measurement points G. 1 ,G 2 ,G 3 G N ,S 1 ,S 2 ,S 3 ···S L It is a line segment formed by connecting two different measurement points.

[0038] Here, the multiple baselines that make up the triangular network are 1 ,G 2 ,G 3 G N and point S consisting of points PS 1 ,S 2 ,S 3 ···S L The triangulation network includes one or more baselines connecting the measurement stations G and G. 1 ,G 2 ,G 3 G N and measurement station G 1 ,G 2 ,G 3 G N may include one or more baselines connecting points S 1 ,S 2 ,S 3 ···S L and point S 1 ,S 2 ,S 3 ···S LIt may include one or more baselines connecting the

[0039] Next, in step S5, the net average calculation unit 11d performs net average calculation based on the multiple three-dimensional triangular nets constructed by the loop closure construction unit 11c. The net average calculation is a calculation method for determining position data by performing the least squares method on the positions of the vertices of a triangle under constraint conditions such as corner conditions and side conditions. A detailed description of the three-dimensional net average calculation is omitted since it is publicly known and is described in detail in, for example, "Theory of Least Squares Method and Its Applications" (written by Tajima Minoru et al., Toyo Shoten). The provisional three-dimensional coordinate position of the position-specified point is corrected by the net average calculation of the net average calculation unit 11d. This makes it possible to calculate the three-dimensional coordinate position of the position-specified point with high accuracy. The loop closure construction unit 11c and the net average calculation unit 11d constitute a correction unit 15.

[0040] Finally, in step S6, the precise three-dimensional coordinate position of the calculated position identification point is displayed on the display unit 7 and output by the output unit 8. Although the case where the ring closure construction unit 11c constructs a triangular network has been described, the ring closure construction unit 11c may construct a polygon having four or more sides.

[0041] As described above, the position calculation method according to the present disclosure calculates a position based on one or more measurement stations G based on signals from a plurality of first satellites 5a of the global positioning satellite system. 1 ,G 2 ,G 3 G N and detects one or more points S based on a signal from a second satellite 5b, which is an example of a signal related to remote sensing. 1 ,S 2 ,S 3 ···S L The position information of at least one measurement point (position-specific point) is calculated based on one or more baselines constructed by connecting two different measurement points among a plurality of measurement points consisting of one or more measurement stations and one or more locations, and the one or more baselines are corrected based on the position information of at least one measurement point (position-specific point). 1 ,G 2 ,G 3 G N and point S1 ,S 2 ,S 3 ···S L Includes line segments constructed by connecting the

[0042] According to the present disclosure, the measurement station G calculated based on signals from a plurality of first satellites 5a of the global positioning satellite system 1 1 ,G 2 ,G 3 G N In addition to the calculated position of the point S, which is calculated based on the remote sensing signal 1 ,S 2 ,S 3 ···S L The calculated position of is also used to perform baseline analysis. Therefore, it is possible to increase the number of measurement points without placing a measurement station, so the measurement station G 1 ,G 2 ,G 3 G N In comparison with a case where the position of at least one measurement point is precisely calculated using only the calculated position, the position of the at least one measurement point can be calculated with high accuracy. Therefore, the measurement position of the at least one measurement point can be calculated with high accuracy on the order of millimeters.

[0043] In addition, the global positioning satellite system 1 includes a plurality of measurement stations G using signals from the first satellites 5a. 1 ,G 2 ,G 3 G N Calculate the location information of multiple points S using remote sensing techniques. 1 ,S 2 ,S 3 ···S L The position information of the measurement station G may be calculated. 1 ,G 2 ,G 3 G N and multiple points S 1 ,S 2 ,S 3 ···S L Two different measurement points G among multiple measurement points consisting of 1 ,G 2 ,G 3G N ,S 1 ,S 2 ,S 3 ···S L A plurality of different loop closures may be constructed using the plurality of baselines, and the position of at least one measurement point may be corrected based on the loop closure difference in the plurality of loop closures.

[0044] According to this configuration, the measurement station G calculated based on signals from a plurality of first satellites 5a of the global positioning satellite system 1 ,G 2 ,G 3 G N In addition to the calculated position of the point S, which is calculated based on the remote sensing signal 1 ,S 2 ,S 3 ···S L The number of loop closures can be increased because the calculated position of is also used to perform baseline analysis. Therefore, it is easy to calculate the measurement position of at least one measurement point with millimeter-level high accuracy.

[0045] In addition, the position calculation system 50 according to the present disclosure calculates the position of one or more measurement stations G based on signals from a plurality of first satellites 5a of the global positioning satellite system. 1 ,G 2 ,G 3 G N a first calculation unit 11a for calculating position information of one or more points S based on a signal related to remote sensing; 1 ,S 2 ,S 3 ···S L and a second calculation unit 11b for calculating the position information of two different measurement points G among a plurality of measurement points constituted by one or more measurement stations and one or more points. 1 ,G 2 ,G 3 G N ,S 1 ,S 2 ,S 3 ···S Land a correction unit 15 that corrects position information of at least one measurement point based on one or more baselines constructed by connecting the measurement stations G 1 ,G 2 ,G 3 G N and point S 1 ,S 2 ,S 3 ···S L Includes line segments constructed by connecting the

[0046] According to the present disclosure, the measurement station G calculated by the first calculation unit 11a based on signals from a plurality of first satellites 5a of the global positioning satellite system 1 ,G 2 ,G 3 G N In addition to the calculated position of the point S, the second calculation unit 11b calculates the point S based on the signal related to remote sensing. 1 ,S 2 ,S 3 ···S L The calculated position of is also used to perform baseline analysis. Therefore, it is possible to increase the number of measurement points without placing a measurement station. 1 ,G 2 ,G 3 G N In comparison with the case where the position of at least one measurement point is precisely determined using only the calculated position, it is easier for the correction unit 15 to correct the position of at least one measurement point with high precision, and to calculate the measurement position of at least one measurement point with high precision at the millimeter level.

[0047] In addition, the first calculation unit 11a calculates the position of the measurement station G by using signals from a plurality of first satellites 5a of the global positioning satellite system. 1 ,G 2 ,G 3 G N The second calculation unit 11b calculates the position information of the plurality of points S by using a remote sensing technique. 1 ,S 2 ,S 3 ···S L The correction unit 15 calculates the position information of the measurement stations G 1 ,G2 ,G 3 G N and multiple points S 1 ,S 2 ,S 3 ···S L Two different measurement points G among multiple measurement points consisting of 1 ,G 2 ,G 3 G N ,S 1 ,S 2 ,S 3 ···S L A plurality of baselines are constructed by connecting the above-mentioned points, and then a plurality of different loop closures are constructed using the plurality of baselines. The correction unit 15 calculates at least one measurement point G based on the loop closure difference in the plurality of loop closures. 1 ,G 2 ,G 3 G N ,S 1 ,S 2 ,S 3 ···S L The position of may be corrected.

[0048] According to this configuration, the measurement station G calculated by the first calculation unit 11a based on signals from a plurality of first satellites 5a of the global positioning satellite system 1 ,G 2 ,G 3 G N In addition to the calculated position of the point S, the second calculation unit 11b calculates the point S based on the signal related to remote sensing. 1 ,S 2 ,S 3 ···S L Since the baseline analysis is performed using the calculated position of the measurement point, the number of loop closures can be increased. Therefore, the correction unit 15 can easily correct the measurement position of at least one measurement point with high accuracy of millimeter level.

[0049] The present disclosure is not limited to the above-described embodiment and its modified examples, and various improvements and modifications are possible within the scope of the claims of the present application and their equivalents.

[0050] For example, in the above embodiment, first, the measurement station G is detected based on the RTK technology. 1 ,G 2 ,G 3 G N However, instead of RTK technology, PPP (Precise Point Positioning) technology was used to calculate the location of measurement station G based on the carrier phase without using fixed station K. 1 ,G 2 ,G 3 G N The position of may be calculated.

[0051] In the above embodiment, at least one measurement point G 1 ,G 2 ,G 3 G N ,S 1 ,S 2 ,S 3 ···S L However, the position of the measurement point G was corrected using RTK or PPP technology. 1 ,G 2 ,G 3 G N ,S 1 ,S 2 ,S 3 ···S L After determining the three-dimensional coordinate position of each measurement point with high accuracy, at least one measurement point G is calculated based on the baseline distance, which is the distance between two measurement points, using the least squares method, Kalman filter, factor graph optimization, etc. 1 ,G 2 ,G 3 G N ,S 1 ,S 2 ,S 3 ···S L The three-dimensional coordinates of the object may be calculated with high accuracy.

[0052] Furthermore, when performing remote sensing, the location of the PS point was calculated using the second satellite 5b equipped with a SAR sensor, but when performing remote sensing, the location of the PS point may be calculated by performing interferometric SAR analysis using an aircraft equipped with a SAR sensor instead of the second satellite 5b.

[0053] In addition, in the above embodiment, the position of the measurement point is expressed in three-dimensional coordinates, but the position of the measurement point may also be expressed in four-dimensional coordinates consisting of a one-dimensional position based on the time when the measurement of the measurement point was performed and a three-dimensional spatial position measured for that measurement point, and the baseline may be a line segment connecting two measurement points in the four-dimensional coordinates.

[0054] Fig. 4 is a schematic diagram of a positioning satellite system 101 according to a modified example, and Fig. 5 is a block diagram showing the main configuration of a position calculation device I' according to a modified example. Note that Fig. 4 shows only one measurement station and one point (PS point).

[0055] As shown in FIG. 5, the control unit 111 of the control device 110 in the position calculation device I′ of the position calculation system 150 includes a four-dimensional position calculation unit 111a, a loop closure construction unit 111b, and a mesh average calculation unit 111c. The four-dimensional position calculation unit 111a calculates the position of each measurement station G based on the RTK technology. 1 ,G 2 ,G 3 G N The location of the four-dimensional coordinates of the point (PS point) S is calculated based on the interferometric SAR technology. 1 ,S 2 ,S 3 ···S L Calculate the 4-dimensional coordinate location of.

[0056] The four-dimensional position calculation unit 111a calculates the measurement point G 1 ,G 2 ,G 3 G N ,S 1 ,S 2 ,S 3 ···S L The average measurement position in the three-dimensional space is calculated. 1 ,G 2 ,G 3 G N ,S 1 ,S 2 ,S 3 ···S LThe time period may vary, for example, be set to several minutes, several hours, or several days.

[0057] The four-dimensional position calculation unit 111a identifies the time when each measurement was performed. The time when each measurement was performed may be any time within the above-mentioned predetermined time. For example, the four-dimensional position calculation unit 111a identifies the time when each measurement was performed as the center time of the predetermined time when each measurement was performed. This identifies the location in the four-dimensional space-time coordinate for each measurement. In FIG. 4, the subscripts in G, S, K, and I' indicate the time when the measurement was performed.

[0058] In order to match the dimension of a one-dimensional coordinate related to time in a four-dimensional space-time coordinate system with the dimension of a three-dimensional coordinate related to space, for example, the elapsed time T (seconds) from the reference time in each measurement is multiplied by 1 (meters / second) to convert it into the dimension of distance (meters). Furthermore, the distance thus obtained is multiplied by a constant C. The constant can be calculated, for example, as follows.

[0059] First, the reference time when the earliest measurement was taken is set to 0, and for each measurement, the elapsed time (seconds) from that reference time is set to the measurement time. Next, the average of the distances between all two points at multiple measurement points is calculated. This calculation can be performed as follows. First, when measurements are taken at different times at each point, the average location in 3D space coordinates at all times is found. This is performed for each measurement point. When a measurement is taken at only time 1 at a certain measurement point, the location in 3D space coordinates at that measurement is set to the location in 3D space coordinates of that measurement point.

[0060] Next, the average of the distances between all two of the multiple measurement points is calculated. This calculation is performed by finding the average of the distances between two of all different measurement points based on the average location of each measurement point in the three-dimensional space calculated as described above. When there are M measurement points, M This means finding the average L (meters) of C2=M·(M-1) / (2×1) different distances.

[0061] Finally, the maximum time in the measurements, that is, the elapsed time Tmax×1 (meters) from the reference time in the most recent measurement is identified, and a dimensionless constant C is determined so that Tmax×C=L. This constant C is multiplied by the one-dimensional value related to the time in all measurements. Note that the value of the elapsed time Tmax (seconds) is multiplied by 1 based on the method for determining units described above, so that it has the dimension of distance (meters).

[0062] In this way, the one-dimensional value related to time in the four-dimensional coordinate system (which has the dimension of meters) can be adjusted to be approximately the same as the three-dimensional value related to space (meters), preventing the one-dimensional value related to time in the four-dimensional coordinate system from becoming a value that is far removed from the three-dimensional value related to space.

[0063] This calculation allows the four-dimensional coordinate position of each measurement point for each measurement to be calculated. This calculation is performed by the four-dimensional position calculation unit 111a. The method of calculating the one-dimensional value related to time in the four-dimensional coordinate is not limited to the method described above. For example, in the above method, the average of the distances between two points of all different measurement points is used, but instead of the average, the maximum distance among the distances between two points of a plurality of measurement points may be used. The one-dimensional value related to time in the four-dimensional coordinate may be converted to distance (meters) using any conversion method.

[0064] The four-dimensional coordinate values ​​of each measurement point calculated by the four-dimensional position calculation unit 111a are temporarily stored in the storage unit 12. The closed loop construction unit 111b selectively constructs a triangular mesh. First, the closed loop construction unit 111b determines the four-dimensional coordinate of one measurement for which it is desired to precisely calculate the four-dimensional coordinate as the position measurement point among the multiple four-dimensional coordinate values ​​of each measurement of each measurement point (measurements at different times are different measurement points even for the same measurement location).

[0065] The loop closure construction unit 111b selectively constructs a plurality of four-dimensional triangular networks that can precisely determine the four-dimensional coordinate positions of the position-specific points. A triangular network is a collection of a plurality of triangles in four-dimensional coordinates that are constructed by connecting the measurement points as vertices of the triangles with straight lines. At least one vertex of the triangle included in the triangular network is composed of the position-specific point. However, the plurality of measurement points and the position measurement points include two or more points that are measured at different times.

[0066] The mesh average calculation unit 111c performs a four-dimensional mesh average calculation based on the multiple four-dimensional triangular meshes constructed by the loop closure construction unit 111b. The four-dimensional mesh average calculation can be performed in exactly the same way as the three-dimensional mesh average calculation, simply by expanding three dimensions to four dimensions.

[0067] In detail, the expansion from 3 dimensions to 4 dimensions is as follows: When the coordinates of point A are (a1, a2, a3) and the coordinates of point B are (b1, b2, b3) in the 3-dimensional calculation, ((a1-b1) 2 +(a2-b2) 2 +(a3-b3) 2 ) 1 / 2 The formula for calculating the distance between points A and B is as follows: In 4 dimensions, the coordinates of point A are (a0, a1, a2, a3) and the coordinates of point B are (b0, b1, b2, b3). Then, ((a0-b0) 2 +(a1-b1) 2 +(a2-b2) 2 +(a3-b3) 2 ) 1 / 2 This can be done simply by changing

[0068] In addition, in the case of 4D, as in the case of 3D, the 4D position of at least one measurement point can be calculated with high accuracy by the least squares method, Kalman filter, factor graph optimization, etc. instead of loop closure. Also, in 4D, PPP technology can be used instead of RTK technology as in the case of 3D.

[0069] In a method of performing network averaging based on position information at a single time for each of multiple points, even if the most accurate RTK (Real-Time Kinematic) technology is used, if the measurement position changes suddenly in a short period of time due to crustal movement, etc., it is not easy to calculate the measurement position with high accuracy.

[0070] In contrast, according to the present configuration, since each baseline includes time information, it is easy to correct the change in the measurement position of the measurement point over time. Therefore, even if the measurement position changes suddenly in a short period of time due to crustal movement, for example, the measurement error can be reduced, and as a result, the measurement position of the measurement point can be easily calculated with high accuracy.

[0071] The technology disclosed herein significantly improves the accuracy of movement analysis, making it possible to grasp the position of objects and the movement status of stationary objects with millimeter accuracy in real time. Furthermore, by using this technology, it is possible to extremely accurately correct the positions of images, maps, topography, building information, etc. from smartphones and satellites. [Explanation of symbols]

[0072] 1,101 Positioning satellite system, 5a First satellite, 5b Second satellite, 6 Receiving unit, 7 Display unit, 8 Output unit, 10 Control device, 11 Control unit, 11a First calculation unit, 11b Second calculation unit, 11c, 111b Loop closure construction unit, 11d, 111c Net average calculation unit, 12 Memory unit, 15 Correction unit, 50, 150 Position calculation system, 111 Control unit, 111a Four-dimensional position calculation unit, 150 Position calculation system, G 1 ,G 2 ,G 3 G N Measuring station I,I′ Position calculation device, K Fixed station, S 1 ,S 2 ,S 3 ···S L Point (PS point)

Claims

1. Calculating position information of a measuring station based on signals from a plurality of satellites and calculating position information of a point based on signals related to remote sensing; correcting the position information of at least one of the measurement points based on a baseline constructed by connecting two different measurement points among the two or more measurement points constituted by the measurement station and the location; A position calculation method, wherein the baseline includes a line segment constructed by connecting the measurement station and the point.

2. Calculating position information of the plurality of measurement stations using signals from the plurality of satellites, and calculating position information of the plurality of points using a remote sensing technique; Constructing a plurality of baselines by connecting two different measurement points among the plurality of measurement points constituted by the plurality of measurement stations and the plurality of locations; Constructing a plurality of different circular closures using a plurality of said baselines; The position calculation method according to claim 1 , further comprising the step of correcting the position of the at least one measurement point based on a loop closure difference among a plurality of the loop closures.

3. The position of the measurement point is represented by a four-dimensional coordinate position composed of a one-dimensional position based on the time when the measurement of the measurement point was performed and a three-dimensional spatial position measured with respect to the measurement point, The position calculation method according to claim 1 , wherein the base line is a line segment connecting two points in the four-dimensional coordinate system.

4. a first calculation unit that calculates position information of a measurement station based on signals from a plurality of satellites; A second calculation unit that calculates position information of a point based on a signal related to remote sensing; and a correction unit that corrects the position information of at least one of the measurement points based on a baseline constructed by connecting two different measurement points among the two or more measurement points constituted by the measurement station and the location, A position calculation system, wherein the baseline includes a line segment constructed by connecting the measurement station and the point.

5. The first calculation unit calculates position information of the plurality of measurement stations using signals from the plurality of satellites, and the second calculation unit calculates position information of the plurality of points using the remote sensing technique, The correction unit constructs a plurality of baselines by connecting two different measurement points among the plurality of measurement points constituted by the plurality of measurement stations and the plurality of locations, and then constructs a plurality of different loop closures using the plurality of baselines; The position calculation system according to claim 4 , wherein the correction unit corrects the position of the at least one measurement point based on a loop closure difference among the plurality of loop closures.

Images