Positioning accuracy output system and server device thereof

Abstract

To present to contractors a state of positioning accuracy of a construction machine that uses a satellite positioning system in an easily understandable manner and assist in systematic and efficient construction work.SOLUTION: A positioning accuracy output system 1 comprises: a construction machine 10 that performs positioning on the basis of radio waves from a positioning satellite 20; and a server device 30 for outputting a state of positioning accuracy of the construction machine 10. The construction machine 10 includes a GNSS receiver 11 for performing positioning on the basis of the satellite information of the positioning satellite 20 and acquiring the position information of the construction machine 10. The construction machine 10 further includes a controller 12 for calculating positioning accuracy on the basis of the satellite information and acquiring positioning accuracy information. The server device 30 assesses the state of positioning accuracy at the position of the construction machine 10 on the basis of the position information, positioning accuracy information and satellite information transmitted from the construction machine 10 and outputs a symbol 415 that corresponds to the result of assessment.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a positioning accuracy output system and a server device thereof. [Background technology]

[0002] Information-based construction, which applies information and communication technology to construction using hydraulic excavators and other construction machinery, is being promoted. In information-based construction, machine control (3D-MC) or machine guidance (MG) of construction machinery is performed so that construction is carried out according to 3D design data while 3D surveying of the construction target is performed, and construction progress and construction accuracy are managed using position information of the construction machinery and the construction target (for example, Patent Document 1).

[0003] Patent document 1 describes a work machine having a calculation unit that calculates the position coordinates of the vehicle body and the longitudinal direction of the work machine from the measurement results of a position measuring device and an orientation measuring device, an information generating unit that sets another design surface adjacent to a first target surface among multiple design surfaces that make up the 3D design data as a second target surface and generates first operation support information including the amount of rotation of the upper rotating body to make the longitudinal direction of the work machine when viewed from above the vehicle body parallel to the boundary line between the first target surface and the second target surface, and an information output unit that outputs the first operation support information generated by the information generating unit to a display device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-157600 A Summary of the Invention [Problem to be solved by the invention]

[0005] In information-based construction, a satellite positioning system is used to position and survey the construction machine and the construction target. In the satellite positioning system, the positioning accuracy may be reduced due to the influence of the position of the positioning satellite and multipath, such that highly accurate position information cannot be calculated or the position information jumps up discontinuously. If the positioning accuracy is reduced, the construction accuracy may be reduced or machine control may be impossible, so that the construction company at the construction site may stop the construction work using the satellite positioning system. It is important to let the construction company understand the state of the positioning accuracy, but the construction machine of Patent Document 1 does not take this into consideration at all, and depending on the state of the positioning accuracy, there is a possibility that the construction work cannot be carried out as planned.

[0006] In consideration of the above circumstances, the present invention aims to provide a positioning accuracy output system and its server device that can easily present the positioning accuracy status of construction machinery that uses a satellite positioning system to construction workers, thereby supporting planned and efficient construction work. [Means for solving the problem]

[0007] In order to solve the above problems, the positioning accuracy output system of the present invention is a positioning accuracy output system having a construction machine that performs positioning based on radio waves from a positioning satellite, and a server device that is communicatively connected to the construction machine and outputs the status of the positioning accuracy of the construction machine, wherein the construction machine is equipped with a GNSS receiver that acquires satellite information including information regarding the position and orbit of the positioning satellite from the radio waves, performs positioning based on the satellite information, and acquires position information of the construction machine, and a controller that calculates the positioning accuracy based on the satellite information and acquires positioning accuracy information, and the server device judges the status of the positioning accuracy at the position of the construction machine based on the position information, the positioning accuracy information, and the satellite information transmitted from the construction machine, and outputs a symbol according to the judgment result. Effect of the Invention

[0008] According to the present invention, the state of positioning accuracy of construction machinery that utilizes a satellite positioning system can be presented to construction workers in an easily understandable manner, thereby supporting planned and efficient construction work. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing the configuration of a positioning accuracy output system according to an embodiment of the present invention. [Diagram 2] A diagram explaining the RTK-GPS positioning method. [Diagram 3] FIG. 2 is a diagram showing a functional configuration of the positioning accuracy output system shown in FIG. [Figure 4] 10 is a flowchart showing the flow of a process for determining the state of positioning accuracy. [Diagram 5] 5 is a flowchart showing the flow of processing relating to prediction of multipaths shown in FIG. 4; [Figure 6] FIG. 4 is a diagram showing a first example of a screen displayed on a display unit of the terminal device. [Figure 7] FIG. 11 is a diagram showing a second example of a screen displayed on the display unit of the terminal device. [Figure 8] FIG. 13 is a diagram showing a third example of a screen displayed on the display unit of the terminal device. [Figure 9] FIG. 13 is a diagram showing a fourth example of a screen displayed on the display unit of the terminal device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Components with the same reference numerals in each embodiment have the same functions in each embodiment unless otherwise specified, and the description thereof will be omitted.

[0011] FIG. 1 is a diagram showing a configuration of a positioning accuracy output system 1 of the present embodiment.

[0012] The positioning accuracy output system 1 is a system that outputs the state of the positioning accuracy of a construction machine 10 that uses a satellite positioning system to perform positioning. The positioning accuracy output system 1 has a construction machine 10, a positioning satellite 20, a server device 30, and a terminal device 40.

[0013] The construction machine 10 is a construction machine such as a hydraulic excavator or a dump truck that can measure its own position based on radio waves from a positioning satellite 20. In Fig. 1, the construction machine 10 is shown as an example of a hydraulic excavator equipped with a lower traveling body 10a, an upper rotating body 10b, and a front working machine 10c.

[0014] The construction machine 10 is equipped with a GNSS (Global Navigation Satellite System) receiver 11 that receives radio waves from positioning satellites 20, a controller 12 that performs various processes according to various programs and performs overall control of each component of the construction machine 10, and a communication device 13 that communicates with a server device 30. Furthermore, the construction machine 10 is equipped with a monitor 14 that displays the processing results of the controller 12 and the operating status of the construction machine 10, and a camera 15 equipped with a wide-angle lens, such as a hemispherical or spherical camera, that captures images of the surroundings of the construction machine 10 and the sky above.

[0015] The positioning satellite 20 is an artificial satellite constituting a satellite positioning system such as Japan's Quasi-Zenith Satellite System (QZSS), the United States' GPS, the European Union's Galileo, China's BeiDou, or Russia's GLONASS. The server device 30 is a device such as a cloud server that is communicatively connected to the construction machine 10, manages the construction machine 10, and outputs information indicating the state of the positioning accuracy of the construction machine 10. The terminal device 40 is a device such as a tablet or PC that is communicatively connected to the server device 30 and presents information indicating the state of the positioning accuracy transmitted from the server device 30 to a construction company or the like. The terminal device 40 includes a display unit 41 such as a touch panel display, and displays information indicating the state of the positioning accuracy transmitted from the server device 30 on the display unit 41.

[0016] FIG. 2 is a diagram for explaining the RTK-GPS positioning method.

[0017] There are two types of positioning methods using satellite positioning systems: the independent positioning method used for car and ship navigation, and the relative positioning method. The relative positioning method improves accuracy by correcting errors through relative positioning with a reference point. In the independent positioning method, the distance between the satellite and the GNSS receiver is calculated from the time when the four positioning satellites orbiting about 20,000 km above the ground send out radio waves and the time when the GNSS receiver on the ground receives the radio waves, and the position of the GNSS reception is calculated from the relative positions of the positioning satellites and the distance from the satellites. Here, four positioning satellites are required to determine a three-dimensional position because time is one variable. In the independent positioning method, radio wave delays are a factor in errors.

[0018] On the other hand, in the relative positioning method, four or more positioning satellites are captured simultaneously by two or more GNSS receivers. In this case, the time difference when the radio waves from the positioning satellites reach each GNSS receiver is calculated based on the position of the positioning satellite, and the relative positional relationship between the two or more GNSS receivers is calculated. Since each GNSS receiver receives radio waves from the same positioning satellite, the weather conditions until the radio waves from the positioning satellites reach the ground are the same, and the position error of the positioning satellite and the delay of the radio waves due to the troposphere or ionosphere are eliminated. In addition, in the relative positioning method, the difference in the time it takes for the radio waves from the positioning satellites to reach each GNSS receiver is calculated by the difference in the phase of the radio waves. In this case, the phase (distance from the satellite) contains uncertainty (integer value bias) of the number of waves (an integer part of 2π), so a complex calculation is required to remove this.

[0019] Relative positioning methods include D-GPS (Differential GPS), which uses multiple GNSS receivers to perform stand-alone positioning and determine the relative position from their respective position information, and RTK-GPS (Real-Time Kinematic GPS; interferometric positioning method), which determines the relative positions between multiple GNSS receivers from the distances between each GNSS receiver and a positioning satellite. D-GPS performs positioning using code information contained in radio waves. RTK-GPS performs positioning using phase data of radio waves. D-GPS and RTK-GPS simultaneously receive radio waves from positioning satellites at a reference station whose position is known and at a measurement point whose position is to be determined, and transmit the phase data measured at the reference station to the measurement point in real time by wireless or other means, thereby determining the position of the measurement point with high accuracy.

[0020] Specifically, D-GPS calculates the difference between the reference position at the reference station and the measured coordinate value, and transmits it to the measurement point as correction information, whereas RTK-GPS calculates the phase data of the radio waves received at the reference station (base) and measurement point (rover), and transmits the phase data calculated at the reference station to the measurement point.

[0021] FIG. 2 is an explanatory diagram of RTK-GPS, showing an example in which four positioning satellites 20a to 20d fly above a construction machine 10, which is a measurement point, and a reference station 25 is installed around the construction machine 10. The GNSS receiver 11 of the construction machine 10 is also called a mobile station. The GNSS receiver 11 of the construction machine 10 and the GNSS receiver of the reference station 25 simultaneously receive radio waves from the positioning satellites 20a to 20d. The reference station 25 transmits measured phase data to the GNSS receiver 11 of the construction machine 10. The GNSS receiver 11 analyzes the phase data of the received radio waves and the phase data transmitted from the reference station 25 in real time to determine the relative positional relationship from the reference station 25, and can determine the position of the measurement point with high accuracy.

[0022] The phase data of the radio wave is expressed as in equation (1).

number

[0023] In equation (1), Φ iA is the carrier phase data from the positioning satellite i measured by the GNSS receiver A. f is the carrier frequency. c is the speed of light. r iA is the true distance between GNSS receiver A and positioning satellite i. d i is the error in the carrier phase data due to the clock error of the positioning satellite i. δ A is the error in the carrier phase data due to the internal clock error of GNSS receiver A. N iA is an ambiguity (integer value). From equation (1), the true distance r between GNSS receiver A and positioning satellite i is iA As a result, for example, a distance R1 from the positioning satellite 20a to the GNSS receiver 11 and a distance R2 from the positioning satellite 20a to the reference station 25 are determined. Then, the distance L (baseline length) between the construction machine 10, which is the measurement point, and the reference station 25 is determined from the difference between the distances R1 and R2. This makes it possible to determine the position of the construction machine 10, which is the measurement point, with high accuracy.

[0024] In addition, RTK-GPS generally uses radio waves from six or more positioning satellites to determine the distance to the positioning satellite. Furthermore, there is a method of RTK-GPS called network-type RTK-GPS. In network-type RTK-GPS, errors contained in the measurement points are corrected using real-time survey data from electronic reference points. In D-GPS and RTK-GPS, various error factors are eliminated, so the position accuracy of D-GPS is about a few meters, and that of RTK-GPS is about a few centimeters.

[0025] Error factors in RTK-GPS include errors due to the position of the positioning satellite. The positioning error of the measurement point varies depending on the position of the positioning satellite. Ideally, the positions of the positioning satellites are distributed relatively at high and low altitudes. Radio waves from low-altitude positioning satellites are a cause of error because the distance the radio waves pass through the atmosphere is long. Positioning satellites lower than the horizon are unable to be captured when the satellite moves, which causes errors. In addition, clock errors and GNSS receiver noise are also causes of errors. In addition, the relative positioning method, unlike the point-based positioning method, aims to improve the positioning accuracy of the baseline length by receiving radio waves at multiple measurement points and offsetting the effects of error factors common to each measurement point.

[0026] Another error factor in RTK-GPS is the orbit of the positioning satellite. The position of the positioning satellite is determined using orbit information contained in the radio waves from the positioning satellite. This orbit information is monitored and corrected by a ground monitoring station, but before it is corrected, it drifts due to disturbances such as the gravitational forces of the sun and moon, and the radiation pressure of sunlight, causing errors.

[0027] Another error factor in RTK-GPS is the influence of obstacles such as buildings. Radio waves from positioning satellites are extremely weak and have properties similar to light, so they may be reflected by obstacles before reaching the GNSS receiver (multipath). This can reduce the positioning accuracy of the GNSS receiver. In particular, radio waves from low-altitude positioning satellites close to the horizon propagate long distances through the Earth's atmosphere, and so the propagation error is often large.

[0028] FIG. 3 is a diagram showing a functional configuration of the positioning accuracy output system 1 shown in FIG.

[0029] The GNSS receiver 11 of the construction machine 10 includes a satellite information acquisition unit 111 and a position information acquisition unit 112. The satellite information acquisition unit 111 acquires satellite information from radio waves from the positioning satellite 20. The satellite information includes information on the identification number, position, orbit, and radio wave transmission time of the positioning satellite 20. The satellite information may be acquired in accordance with the NMEA format. The NMEA format is a specification for marine electronic devices such as sonars, anemometers (wind vane and anemometers), and is defined by the Marine Electronics Association. The satellite information acquisition unit 111 outputs the acquired satellite information to the position information acquisition unit 112 and the controller 12. The position information acquisition unit 112 performs positioning based on the satellite information and acquires position information of the construction machine 10. The position information acquisition unit 112 may perform positioning by, for example, the above-mentioned RTK-GPS positioning method. The position information acquisition unit 112 outputs the acquired position information to the controller 12.

[0030] The controller 12 of the construction machine 10 acquires the position information (three-dimensional coordinates) of the undercarriage 10a, the upper revolving body 10b, or the front work implement 10c of the construction machine 10 from the position information from the GNSS receiver 11, and compares it with the three-dimensional design data stored in advance or the three-dimensional construction data generated from the three-dimensional design data. Then, the controller 12 automatically controls the operation of the undercarriage 10a, the upper revolving body 10b, or the front work implement 10c of the construction machine 10 (3D-MC) so that construction is performed according to the three-dimensional design data or the three-dimensional construction data, or displays guidance on the monitor 14 (MG). The three-dimensional design data and the three-dimensional construction data may be data transmitted in advance from the server device 30 that manages the construction machine 10.

[0031] In addition, the controller 12 calculates the positioning accuracy of the construction machine 10 (GNSS receiver 11) based on the satellite information of the positioning satellites 20 output from the GNSS receiver 11, and acquires positioning accuracy information. Specifically, the controller 12 includes a calculation condition setting unit 121, a positioning accuracy calculation unit 122, and a transmission processing unit 123.

[0032] The calculation condition setting unit 121 sets the calculation conditions of the positioning accuracy in the positioning accuracy calculation unit 122. The calculation condition setting unit 121 specifies the position information of the construction machine 10 to be calculated and the satellite information of the positioning satellite 20, as well as information and calculation conditions of the positioning accuracy previously calculated, and sets them in the positioning accuracy calculation unit 122 as the calculation conditions of the positioning accuracy.

[0033] The positioning accuracy calculation unit 122 calculates the positioning accuracy of the construction machine 10 based on the above calculation conditions including the satellite information, and acquires the positioning accuracy information. The positioning accuracy calculation unit 122 outputs the acquired positioning accuracy information to the transmission processing unit 123.

[0034] In this embodiment, the positioning accuracy calculation unit 122 calculates the Position Dilution of Precision (hereinafter also referred to as "PDOP") as the positioning accuracy, and sets the calculated PDOP value as the positioning accuracy information.

[0035] The PDOP is calculated using the Horizontal Dilution of Precision (HDOP) and the Vertical Dilution of Precision (VDOP) as shown in Equation (2).

number

[0036] HDOP and VDOP are respectively indexes of the horizontal and vertical components of PDOP, are calculated by a method used in existing satellite positioning systems, and are included in the satellite information output from the GNSS receiver 11. The larger the PDOP value, the lower the positioning accuracy, and the smaller the PDOP value, the higher the positioning accuracy. A PDOP value of 1 indicates the highest positioning accuracy. Similarly, for HDOP and VDOP, the larger the respective values, the lower the positioning accuracy, and the smaller the respective values, the higher the positioning accuracy.

[0037] In this way, the positioning accuracy output system 1 calculates the position accuracy degradation rate used in an existing satellite positioning system as the positioning accuracy, and the value of the position accuracy degradation rate is used as the positioning accuracy information, so that the positioning accuracy can be easily calculated and output without using complicated means. This makes it possible for the positioning accuracy output system 1 to be easily introduced into an existing system including a construction machine 10 that uses a satellite positioning system. Therefore, the positioning accuracy output system 1 can easily present the state of the positioning accuracy to a construction company in an easy-to-understand manner, and can easily support planned and efficient construction work.

[0038] The transmission processing unit 123 transmits the position information of the construction machine 10 and the satellite information of the positioning satellite 20 output from the GNSS receiver 11, the positioning accuracy information acquired by the positioning accuracy calculation unit 122, and the image captured by the camera 15 to the server device 30 via the communication device 13.

[0039] The server device 30 is communicably connected to the construction machine 10, which includes the GNSS receiver 11 that performs positioning based on radio waves from the positioning satellites 20 and the controller 12 that calculates the positioning accuracy of the GNSS receiver 11, and outputs the state of the positioning accuracy. The server device 30 judges the state of the positioning accuracy at the position of the construction machine 10 based on the position information of the construction machine 10 transmitted from the construction machine 10, the satellite information of the positioning satellites 20, and the positioning accuracy information, and outputs a symbol according to the judgment result. Specifically, the server device 30 includes a storage unit 31, an arrival prediction unit 32, a multipath prediction unit 33, a positioning accuracy prediction calculation unit 34, a positioning accuracy prediction judgment unit 35, and an output processing unit 36.

[0040] The memory unit 31 is a storage device that stores information transmitted from the construction machine 10 and various information for managing the construction machine 10. The memory unit 31 stores the position information of the construction machine 10, satellite information of the positioning satellites 20, positioning accuracy information (PDOP value), and images captured by the camera 15, all of which are transmitted from the construction machine 10. The memory unit 31 not only stores currently transmitted information as the information transmitted from the construction machine 10, but also stores information transmitted in the past, and accumulates this information.

[0041] The storage unit 31 also stores construction information indicating the construction content of the construction machine 10, and surrounding environment information indicating the position and shape of the surrounding environment of the construction machine 10. The construction information of the construction machine 10 includes information on the construction target such as the above-mentioned three-dimensional design data or three-dimensional construction data, as well as information on the construction plan of the construction machine 10, the progress of construction, and construction accuracy. The surrounding environment information of the construction machine 10 is information on the topography around the construction machine 10, including the construction site of the construction machine 10, and the positions and shapes of ground objects such as buildings and forests. Of the surrounding environment information, the positions and shapes of the topography around the construction machine 10, including the construction site of the construction machine 10, can be obtained from three-dimensional map data. Of the surrounding environment information, the positions and shapes of ground objects such as buildings and forests can be obtained from three-dimensional construction data that may be included in the construction information.

[0042] The arrival prediction unit 32 predicts the arrival of the positioning satellite 20 at the position of the construction machine 10 based on the position information of the construction machine 10 transmitted from the construction machine 10 and the satellite information of the positioning satellite 20. Specifically, the arrival prediction unit 32 acquires information on the current, past, and future positions of the positioning satellite 20 that will arrive at the position of the construction machine 10 from information on the position and orbit of the positioning satellite 20 included in the satellite information of the positioning satellite 20 stored in the memory unit 31. For example, the arrival prediction unit 32 may identify the current and past positions of the positioning satellite 20 that will arrive around or above the construction machine 10 at the position of the construction machine 10. Then, the arrival prediction unit 32 may predict the future position of the arriving positioning satellite 20 from the identified current and past positions of the positioning satellite 20. The arrival prediction unit 32 outputs information about the current, past, and future positions of the positioning satellites 20 that will arrive at the position of the construction machine 10 to the multipath prediction unit 33 and the positioning accuracy prediction calculation unit 34.

[0043] The multipath prediction unit 33 predicts whether or not multipath occurs in radio waves from the positioning satellite 20 based on the arrival information of the positioning satellite 20 output from the arrival prediction unit 32, the surrounding environment information of the construction machine 10 stored in the memory unit 31, and the captured image of the camera 15. When predicting that multipath occurs in radio waves from the positioning satellite 20, the multipath prediction unit 33 identifies the positioning satellite 20 that is the source of the radio waves generating multipath, and sets the positioning accuracy prediction calculation unit 34 so that the satellite information of the identified positioning satellite 20 is excluded from the calculation of the positioning accuracy. The multipath prediction unit 33 outputs the prediction result of the multipath and the arrival information of the positioning satellite 20 to the positioning accuracy prediction calculation unit 34. Details of the process related to the prediction of the multipath will be described later with reference to FIG. 5.

[0044] The positioning accuracy prediction calculation unit 34 performs prediction calculation of the positioning accuracy (PDOP) at the position of the construction machine 10 based on the information on the positions of the positioning satellites 20, the satellite information, and the prediction result of the multipath. Specifically, the positioning accuracy prediction calculation unit 34 may perform prediction calculation of the positioning accuracy by the following method.

[0045] When calculating the positioning accuracy at the current position of the positioning satellite 20, if it is predicted that no multipath will occur in the radio waves from the positioning satellite 20, the positioning accuracy prediction calculation unit 34 may use the positioning accuracy information transmitted from the construction machine 10 and stored in the memory unit 31 as is.

[0046] When calculating the positioning accuracy at the current position of the positioning satellite 20, if it is predicted that multipath will occur in the radio waves from the positioning satellite 20, the positioning accuracy prediction calculation unit 34 may exclude the positioning satellite 20 that is the source of the radio waves generating multipath, and calculate the positioning accuracy from the satellite information of the positioning satellite 20 that remains after the exclusion.

[0047] When calculating the positioning accuracy at the future position of the positioning satellite 20, if it is predicted that no multipath will occur in the radio waves from the positioning satellite 20, the positioning accuracy prediction calculation unit 34 may identify positioning accuracy information at each of the current and past positions of the positioning satellite 20. The positioning accuracy prediction calculation unit 34 may calculate the positioning accuracy at the future position of the positioning satellite 20 from the identified positioning accuracy information at each of the current and past positions of the positioning satellite 20 and the future position of the positioning satellite 20.

[0048] When calculating the positioning accuracy at the future position of the positioning satellite 20, if it is predicted that multipath occurs in the radio waves from the positioning satellite 20, the positioning accuracy prediction calculation unit 34 may exclude the positioning satellite 20 that is the source of the radio waves generating multipath. Positioning accuracy information at each of the current and past positions of the positioning satellite 20 remaining after the exclusion may be specified. The positioning accuracy prediction calculation unit 34 may calculate the positioning accuracy at the future position of the positioning satellite 20 from the positioning accuracy information at each of the current and past positions of the specified positioning satellite 20 and the future position of the positioning satellite 20 remaining after the exclusion.

[0049] The positioning accuracy prediction calculation unit 34 outputs to the positioning accuracy prediction determination unit 35 the positioning accuracy information (PDOP value) at the current or future position of the positioning satellite 20 orbiting at the position of the construction machine 10.

[0050] The positioning accuracy prediction determination unit 35 determines the state of the positioning accuracy at the position of the construction machine 10 based on the positioning accuracy information output from the positioning accuracy prediction calculation unit 34. Specifically, the positioning accuracy prediction determination unit 35 determines the current or future state of the positioning accuracy at the position of the construction machine 10 from the positioning accuracy information at the current or future position of the positioning satellite 20. The state of the positioning accuracy is determined by comparing the value of PDOP indicated by the positioning accuracy information output from the positioning accuracy prediction calculation unit 34 with a threshold range of PDOP set in advance for each state of positioning accuracy. The threshold range of PDOP is set in advance, for example, as follows. That is, the threshold range indicating a state of high positioning accuracy is set in advance to a range in which the PDOP value is smaller than 2. The threshold range indicating a state of medium positioning accuracy is set in advance to a range in which the PDOP value is 2 or more and smaller than 4. The threshold range indicating a state of low positioning accuracy is set in advance to a range in which the PDOP value is 4 or more.

[0051] The positioning accuracy prediction determination unit 35 outputs to the output processing unit 36 ​​the determination result of the state of positioning accuracy at the current or future position of the positioning satellite 20 orbiting the position of the construction machine 10 .

[0052] The output processing unit 36 ​​selects a symbol according to the determination result of the state of the positioning accuracy output from the positioning accuracy prediction determination unit 35. This symbol is information indicating the state of the positioning accuracy, and may be represented by a figure, an icon, or the like. This symbol is stored in advance in association with the state of the positioning accuracy and the threshold range of the PDOP. Details of the process related to the selection of the symbol will be described later with reference to FIG. 4. The output processing unit 36 ​​outputs the selected symbol to the communication device of the server device 30. The communication device of the server device 30 transmits the symbol output from the output processing unit 36 ​​to the terminal device 40. The terminal device 40 displays the symbol transmitted from the server device 30 on the display unit 41.

[0053] Thus, the positioning accuracy output system 1 of this embodiment includes a construction machine 10 that performs positioning based on radio waves from a positioning satellite 20, and a server device 30 that is communicatively connected to the construction machine 10 and outputs the state of the positioning accuracy of the construction machine 10. The construction machine 10 is equipped with a GNSS receiver 11 that acquires satellite information including information on the position and orbit of the positioning satellite 20 from radio waves, performs positioning based on the satellite information, and acquires the position information of the construction machine 10. Furthermore, the construction machine 10 is equipped with a controller 12 that calculates the positioning accuracy based on the satellite information and acquires the positioning accuracy information. The server device 30 judges the state of the positioning accuracy at the position of the construction machine 10 based on the position information, positioning accuracy information, and satellite information transmitted from the construction machine 10, and outputs a symbol 415 according to the judgment result.

[0054] As a result, the positioning accuracy output system 1 can present the state of the positioning accuracy of the construction machine 10 that uses the satellite positioning system to the construction company in an easy-to-understand manner. This makes it easier for the construction company to formulate a plan that allows the construction work to be carried out efficiently. Therefore, the positioning accuracy output system 1 can support planned and efficient construction work.

[0055] Furthermore, the positioning accuracy output system 1 determines the state of positioning accuracy based on the predicted arrival of the positioning satellite 20 and outputs a symbol according to the determination result, so that it can predict the future state of the positioning accuracy and output a symbol according to the predicted result. This allows the positioning accuracy output system 1 to present the future transition of the state of the positioning accuracy to the construction company in an easy-to-understand manner. This makes it easier for the construction company to formulate a plan that allows the construction work to be performed more efficiently. Therefore, the positioning accuracy output system 1 can further support planned and efficient construction work.

[0056] FIG. 4 is a flowchart showing the flow of a process for determining the state of positioning accuracy.

[0057] In step S401, the server device 30 acquires the position information of the construction machine 10 and the satellite information of the positioning satellite 20 transmitted from the construction machine 10 and stored in the memory unit 31.

[0058] In step S402 , the server device 30 predicts the future position of the positioning satellite 20 that will orbit the position of the construction machine 10 based on the position information of the construction machine 10 and the satellite information of the positioning satellite 20 .

[0059] In step S403 , the server device 30 acquires the surrounding environment information stored in the storage unit 31 and the captured image by the camera 15 .

[0060] In step S404, the server device 30 performs a process related to multipath prediction, which will be described later with reference to FIG.

[0061] In step S405, the server device 30 performs a prediction calculation of the positioning precision (PDOP) at the position of the construction machine 10 based on the information on the positions of the positioning satellites 20, the satellite information, and the predicted results of multipath. When it is predicted that multipath occurs in the radio waves from the positioning satellites 20 as described above, the server device 30 excludes the positioning satellites 20 that are the transmission sources of the radio waves generating multipath, and performs a prediction calculation of the positioning precision from the satellite information of the positioning satellites 20 that remain after the exclusion.

[0062] In step S406, the server device 30 compares the PDOP value acquired in step S405 with the above-mentioned PDOP threshold range to determine the state of the positioning precision (PDOP) at the position of the construction machine 10. If the PDOP value acquired in step S405 is smaller than 2, the server device 30 proceeds to step S407. If the PDOP value acquired in step S405 is equal to or greater than 2 and smaller than 4, the server device 30 proceeds to step S409. If the PDOP value acquired in step S405 is equal to or greater than 4, the server device 30 proceeds to step S411.

[0063] In step S407, the server device 30 determines that the positioning accuracy is high, and proceeds to step S408.

[0064] In step S408, the server device 30 selects a symbol corresponding to the determination result that the positioning accuracy is high, for example, a symbol for sunny weather, and proceeds to step S413.

[0065] In step S409, the server device 30 determines that the positioning accuracy is medium, and proceeds to step S410.

[0066] In step S410, the server device 30 selects a symbol corresponding to the determination result that the positioning accuracy is in a medium state, for example, a cloudy symbol, and proceeds to step S413.

[0067] In step S411, the server device 30 determines that the positioning accuracy is low, and proceeds to step S412.

[0068] In step S412, the server device 30 selects a symbol corresponding to the determination result that the positioning accuracy is low, for example, a symbol of rain, and proceeds to step S413.

[0069] In step S413, the server device 30 outputs the selected symbol and transmits it to the terminal device 40. The terminal device 40 displays the symbol transmitted from the server device 30 on the display unit 41. The server device 30 can output various information related to the positioning accuracy and the construction site together with the symbol according to the determination result of the state of the positioning accuracy, and display it on the display unit 41 of the terminal device 40. Details of the information displayed on the terminal device 40 will be described later with reference to Figs. 6 to 9.

[0070] FIG. 5 is a flowchart showing the process flow relating to the multipath prediction (step S404) shown in FIG.

[0071] In step S501, the server device 30 checks the surrounding environment information and the captured image of the camera 15 acquired in step S403, and checks the position of the positioning satellite 20 predicted in step S402. Then, based on the surrounding environment information and the captured image, the server device 30 checks the positions and shapes of terrain such as slopes and ground objects such as buildings that appear in the captured image. Furthermore, based on the position of the positioning satellite 20 and the captured image, the server device 30 checks the position of the positioning satellite 20 in the captured image.

[0072] In step S502, the server device 30 judges whether or not an obstacle that blocks radio waves from the positioning satellite 20 exists in the captured image of the camera 15. Specifically, the server device 30 judges whether or not the position of the positioning satellite 20 in the captured image overlaps with a terrain such as a slope or a ground object such as a building that appears in the captured image. If the position of the positioning satellite 20 in the captured image overlaps with a terrain such as a slope or a ground object such as a building that appears in the captured image, the server device 30 judges the overlapping terrain or ground object as an obstacle that blocks radio waves from the positioning satellite 20. In this case, the server device 30 judges that an obstacle exists in the captured image of the camera 15, and proceeds to step S504. On the other hand, if the position of the positioning satellite 20 in the captured image does not overlap with a terrain such as a slope or a ground object such as a building that appears in the captured image, the server device 30 judges that an obstacle does not exist in the captured image of the camera 15, and proceeds to step S503.

[0073] In step S503, the server device 30 predicts that no multipath occurs in the radio waves from the positioning satellite 20. After that, the server device 30 ends the process shown in Fig. 5, and proceeds to step S405 in Fig. 4.

[0074] In step S504, the server device 30 predicts that multipath will occur in the radio waves from the positioning satellites 20.

[0075] In step S505, the server device 30 masks the portion determined to be an obstacle blocking the radio waves from the positioning satellite 20 in step S502.

[0076] In step S506, the server device 30 identifies the positioning satellites 20 included in the masked portion as the positioning satellites 20 that are the transmission sources of the radio waves that generate multipath. The server device 30 sets the satellite information of the identified positioning satellites 20 so as to be excluded from the predicted calculation of the positioning accuracy. After that, the server device 30 ends the process shown in FIG. 5 and proceeds to step S405 in FIG. 4.

[0077] In this way, the positioning accuracy output system 1 predicts whether or not multipath will occur, judges the state of positioning accuracy based on the predicted result of multipath, and outputs a symbol according to the judgment result, so that the state of positioning accuracy can be judged more accurately and a symbol according to the judgment result can be output. As a result, the positioning accuracy output system 1 can present the accurate state of positioning accuracy to the construction company in an easy-to-understand manner. The construction company can accurately formulate a plan that allows the construction work to be performed efficiently. Therefore, the positioning accuracy output system 1 can properly support planned and efficient construction work.

[0078] FIG. 6 is a diagram showing a first example of a screen 411 displayed on the display unit 41 of the terminal device 40. As shown in FIG.

[0079] The server device 30 can output various information related to the positioning accuracy and the construction site together with a symbol corresponding to the determination result of the state of the positioning accuracy, and display the information on the display unit 41 of the terminal device 40. For example, a screen 411 as shown in Fig. 6 is displayed on the display unit 41 of the terminal device 40. The screen 411 shown in Fig. 6 includes a setting item 412 for setting the display contents of the screen 411, and a display image 413 for displaying information related to the positioning accuracy and the construction site. The display image 413 displays a graph 414 showing the trends of the values ​​of VDOP, HDOP, and PDOP, a symbol 415 corresponding to the determination result of the state of the positioning accuracy, a work section 416 in the construction site where the construction machine 10 is located, and a work process 417 of the construction machine 10.

[0080] The graph 414 is a graph in which the vertical axis 414a indicates the values ​​of VDOP, HDOP, and PDOP, and the horizontal axis 414b indicates time. The larger the VDOP, HDOP, and PDOP values ​​are, the lower the positioning accuracy is, and the smaller the values ​​are, the higher the positioning accuracy is. For a construction worker who is unfamiliar with values ​​such as PDOP, there is a possibility that the larger the value of PDOP, etc. is, the higher the positioning accuracy is. Therefore, the server device 30 creates the graph 414 by inverting the positive and negative directions of the vertical axis 414a, which is one of the axes, and outputs the created graph 414 to display it on the display unit 41 of the terminal device 40.

[0081] As a result, the positioning accuracy output system 1 can output the transition of the positioning accuracy in a format that is intuitively easy to understand even for a construction worker who is unfamiliar with positioning accuracy. Therefore, the positioning accuracy output system 1 can present the state of the positioning accuracy to the construction worker in an even easier-to-understand manner, and can further support planned and efficient construction work.

[0082] 6, a graph 414 showing hourly changes in PDOP, etc., for a specific work section 416 in the construction site on a specific work day, hourly symbols 415, and work processes 417 performed on the specific work day are displayed in association with each other. This one hour is a predetermined time set in advance within the construction period of the construction machine 10, and is a cycle for determining the state of positioning accuracy and outputting the symbol 415. That is, the server device 30 determines the state of positioning accuracy every predetermined time during the construction period of the construction machine 10, outputs the symbol 415 every predetermined time, and displays it on the display unit 41 of the terminal device 40. The server device 30 then outputs the work process 417 of the construction machine 10 in association with the symbol 415, and displays it on the display unit 41 of the terminal device 40.

[0083] This allows the positioning accuracy output system 1 to output the relationship between the flow of the work process 417 of the construction machine 10 and the state of the positioning accuracy in a format that is intuitively easy for the contractor to understand. Therefore, the positioning accuracy output system 1 can present the state of the positioning accuracy when each work process 417 is performed in an easy-to-understand manner to the contractor, further supporting planned and efficient construction work.

[0084] FIG. 7 is a diagram showing a second example of the screen 411 displayed on the display unit 41 of the terminal device 40. As shown in FIG.

[0085] 7 displays the transition of the symbol 415 at each predetermined time in each of a plurality of work sections 416 in the construction site. That is, the server device 30 determines the state of the positioning accuracy in each of the plurality of work sections 416 in the construction site of the construction machine 10, outputs the symbol 415 for each work section 416, and displays it on the display unit 41 of the terminal device 40.

[0086] This allows the positioning accuracy output system 1 to output the difference in the positioning accuracy state for each work section 416 in a format that is intuitively easy for the construction worker to understand. Therefore, the positioning accuracy output system 1 can present the difference in the positioning accuracy state for each work section 416 to the construction worker in an easy-to-understand manner, and can further support planned and efficient construction work.

[0087] FIG. 8 is a diagram showing a third example of the screen 411 displayed on the display unit 41 of the terminal device 40. As shown in FIG.

[0088] The display image 413 shown in Fig. 8 displays a map image 418 of the construction site, and also displays work sections 416 in the construction site and symbols 415 for each work section 416 superimposed on the map image 418. The map image 418 is not limited to a still image, and may be a moving image. The display image 413 shown in Fig. 8 displays a time setting toolbar 419 for displaying the map image 418 and symbols 415 at any time during the construction period. That is, the server device 30 outputs the symbols 415 for each work section 416 superimposed on the map image 418 of the construction site of the construction machine 10, and displays them on the display unit 41 of the terminal device 40.

[0089] This allows the positioning accuracy output system 1 to output the relationship between the environment and work conditions at the construction site and the state of positioning accuracy in a format that is intuitively easy for the construction company to understand. Therefore, the positioning accuracy output system 1 can present the state of positioning accuracy in an easy-to-understand manner to the construction company while comparing it with the environment and work conditions at the construction site, and can further support planned and efficient construction work.

[0090] FIG. 9 is a diagram showing a fourth example of the screen 411 displayed on the display unit 41 of the terminal device 40. As shown in FIG.

[0091] A screen 411 shown in FIG. 9 may display a display image 420 displaying the arrival status of the positioning satellite 20 instead of a display image 413 displaying information about the positioning accuracy and the construction site by operating a setting item 412 for setting the display contents of the screen 411. The display image 420 shown in FIG. 9 is provided with a celestial image 422 on which a position 421 of the positioning satellite 20 at a certain place and at a certain time is plotted, and a time setting toolbar 423 for displaying the celestial image 422 at an arbitrary time. The display image 420 may display the type, position, and orbit of the positioning satellite 20 at an arbitrary place and at an arbitrary time designated by the construction company. That is, the server device 30 can output the type, position, and orbit of the positioning satellite 20 at an arbitrary place and at an arbitrary time designated by the construction company by operating the terminal device 40, and display them on the display unit 41 of the terminal device 40.

[0092] As a result, the positioning accuracy output system 1 can output the positions and number of positioning satellites 20 captured when positioning the construction machine 10 in a format that is intuitively easy for the construction worker to understand. Therefore, the positioning accuracy output system 1 can present to the construction worker in an easy-to-understand manner which positioning satellite 20 has acquired the position information of the construction machine 10 and ensures the positioning accuracy, thereby further supporting planned and efficient construction work.

[0093] In the above embodiment, the server device 30 outputs various information regarding the positioning accuracy, such as symbol 415, and displays it on the display unit 41 of the terminal device 40, but this is not limited to this and the information may also be displayed on the monitor 14 of the construction machine 10.

[0094] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-mentioned embodiments, and various design modifications can be made without departing from the spirit of the present invention described in the claims. In the present invention, the configuration of one embodiment can be added to the configuration of another embodiment, the configuration of one embodiment can be replaced with the configuration of another embodiment, or part of the configuration of one embodiment can be deleted. [Explanation of symbols]

[0095] 1...positioning accuracy output system, 10...construction machine, 11...GNSS receiver, 12...controller, 15...camera, 20, 20a to 20d...positioning satellites, 30...server device, 414...graph, 415...symbol, 416...work area, 417...work process, 418...map image

Claims

1. A positioning accuracy output system having a construction machine that performs positioning based on radio waves from a positioning satellite, and a server device that is communicatively connected to the construction machine and outputs a state of the positioning accuracy of the construction machine, The construction machine includes: a GNSS receiver that acquires satellite information including information regarding the position and orbit of the positioning satellite from the radio waves, performs positioning based on the satellite information, and acquires position information of the construction machine; a controller for calculating the positioning accuracy based on the satellite information and acquiring positioning accuracy information; The controller calculates a position accuracy degradation rate as the positioning accuracy, and sets the value of the position accuracy degradation rate as the positioning accuracy information. The server device includes: predicting the arrival of the positioning satellite at the position of the construction machine based on the satellite information and the position information transmitted from the construction machine, determining the state of the positioning accuracy at the position of the construction machine based on the positioning accuracy information and the arrival prediction, and outputting a symbol according to the determination result; A graph is created in which one axis indicates the value of the position accuracy degradation rate and the other axis indicates time by inverting the positive and negative directions of the one axis, and outputting the created graph. A positioning accuracy output system comprising:

2. The construction machine is equipped with a camera that captures images of the surroundings and the sky above the construction machine, The server device predicts whether or not multipath will occur in the radio waves based on the surrounding environment information of the construction machine, the camera image transmitted from the construction machine, and the arrival prediction, determines the state of the positioning accuracy based on the multipath prediction result, and outputs the symbol according to the determination result.

2. The positioning accuracy output system according to claim 1,

3. A positioning accuracy output system having a construction machine that performs positioning based on radio waves from a positioning satellite, and a server device that is communicatively connected to the construction machine and outputs a state of the positioning accuracy of the construction machine, The construction machine includes: a GNSS receiver that acquires satellite information including information regarding the position and orbit of the positioning satellite from the radio waves, performs positioning based on the satellite information, and acquires position information of the construction machine; a controller for calculating the positioning accuracy based on the satellite information and acquiring positioning accuracy information; The server device includes: predicting the arrival of the positioning satellite at the position of the construction machine based on the satellite information and the position information transmitted from the construction machine, determining the state of the positioning accuracy at the position of the construction machine based on the positioning accuracy information and the arrival prediction, and outputting a symbol according to the determination result; The state of the positioning accuracy is judged at each predetermined time during a construction period of the construction machine, the symbol is output at each predetermined time, and a work process of the construction machine is output in association with the symbol. A positioning accuracy output system comprising:

4. A positioning accuracy output system having a construction machine that performs positioning based on radio waves from a positioning satellite, and a server device that is communicatively connected to the construction machine and outputs a state of the positioning accuracy of the construction machine, The construction machine includes: a GNSS receiver that acquires satellite information including information regarding the position and orbit of the positioning satellite from the radio waves, performs positioning based on the satellite information, and acquires position information of the construction machine; a controller for calculating the positioning accuracy based on the satellite information and acquiring positioning accuracy information; The server device includes: predicting the arrival of the positioning satellite at the position of the construction machine based on the satellite information and the position information transmitted from the construction machine, determining the state of the positioning accuracy at the position of the construction machine based on the positioning accuracy information and the arrival prediction, and outputting a symbol according to the determination result; The state of the positioning accuracy is determined for each of a plurality of work sections in the construction site of the construction machine, and the symbol is superimposed for each work section on a map image of the construction site of the construction machine and output. A positioning accuracy output system comprising:

Images