Positioning device and positioning method

Abstract

This positioning device (1) comprises: an antenna (11) that receives radio waves from a satellite and is mounted on a moving object (3); a positioning unit (12) that calculates a positioning result and positioning accuracy on the basis of the radio waves received by the antenna (11); an antenna position changing unit (13) that changes the position of the antenna (11); an antenna position detection unit (14) that detects the relative position of the antenna (11) with respect to the moving object (3) after the position of the antenna (11) is changed; and a control unit (15) that controls the position of the antenna (11), and determines the position of the moving object (3) on the basis of the positioning result and the relative position when the positioning accuracy is a threshold value or higher.

Description

[Technical field]

[0001] The present disclosure relates to a positioning device and a positioning method for performing satellite positioning. [Background technology]

[0002] Conventionally, the Global Navigation Satellite System (GNSS), which uses radio waves from satellites, has been widely used as a means for detecting (i.e., positioning) the position information of automobiles, robots, etc. For example, Patent Document 1 describes a navigation satellite system receiver that can achieve highly accurate time synchronization and positioning even in an environment where the reception state of navigation satellite signals is poor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-201282 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, when trying to realize satellite positioning using GNSS, radio waves (direct waves) from the satellites may not be received because they are blocked by obstacles such as buildings. In addition, multipath, in which the direct waves are reflected or diffracted by obstacles such as buildings and are received as reflected waves or diffracted waves, causes delays in the arrival time of the radio waves, which can cause errors in the positioning results.

[0005] In consideration of the above circumstances, an object of the present disclosure is to provide a positioning device and a positioning method that realizes stable positioning by changing the position of the antenna when performing satellite positioning, thereby reducing the effects of radio wave blocking and multipath. [Means for solving the problem]

[0006] In order to solve the above problems, the positioning device of the first embodiment is a positioning device that detects the position of a moving body, and includes an antenna mounted on the moving body that receives radio waves from a satellite, a positioning unit that calculates a positioning result (meaning position information of the moving body) and positioning accuracy (meaning a range within which the error in the position information of the moving body is contained (e.g., an error of 5 m)) based on the radio waves received by the antenna, an antenna position changing unit that changes the position of the antenna, an antenna position detection unit that detects the relative position of the antenna with respect to the moving body after the position of the antenna has been changed, and a control unit that controls the position of the antenna, and determines the position of the moving body based on the positioning result and the relative position when the positioning accuracy is equal to or greater than a threshold.

[0007] In order to solve the above problems, the positioning method of the first embodiment is a positioning method in a positioning device that detects the position of a moving body, and includes the steps of receiving radio waves from a satellite by the positioning device, calculating a positioning result and positioning accuracy based on the received radio waves, changing the position of an antenna, detecting the relative position of the antenna with respect to the moving body after changing the position of the antenna, and controlling the position of the antenna, and determining the position of the moving body based on the positioning result and the relative position when the positioning accuracy is equal to or greater than a threshold value. Effect of the Invention

[0008] According to the present disclosure, by changing the position of the antenna when performing satellite positioning, it is possible to reduce the effects of radio wave blocking and multipath and achieve stable positioning. [Brief description of the drawings]

[0009] [Figure 1] 1 is a block diagram showing an example of the configuration of a positioning device according to a first embodiment. [Diagram 2] 1 is a schematic diagram of a positioning device according to a first embodiment. [Diagram 3] 1A to 1C are schematic diagrams illustrating a mechanism for changing the position of an antenna in three dimensions. [Figure 4] FIG. 13 is a schematic diagram illustrating the change in antenna position to reduce the effect of radio wave shielding. [Diagram 5] 4 is a flowchart showing an example of a positioning method executed by the positioning device according to the first embodiment. [Figure 6] FIG. 11 is a block diagram showing an example of the configuration of a positioning device according to a second embodiment. [Figure 7] 10 is a flowchart showing an example of a positioning method executed by a positioning device according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following embodiments, and can be modified in various ways within the scope of the present invention.

[0011] (First embodiment) Fig. 1 is a block diagram showing an example of the configuration of a positioning device 1 according to the first embodiment. As shown in Fig. 1, the positioning device 1 according to the first embodiment includes an antenna 11, a positioning unit 12, an antenna position changing unit 13, an antenna position detection unit 14, and a control unit 15. The positioning device 1 is mounted on a moving object and detects the position of the moving object.

[0012] Fig. 2 is a schematic diagram of the positioning device 1 mounted on a moving object. As shown in Fig. 2, the moving object 3 internally includes a positioning unit 12, an antenna position detection unit 14, and a control unit 15. The antenna position detection unit 14 is mounted at the center of the moving object 3, and a motor 22 is joined to the upper part of the antenna position detection unit 14, and one end of an arm 21 is joined to the motor 22. The antenna position change unit 13 is composed of the arm 21 and the motor 22, and changes the position of the antenna 11 mounted on one end of the arm 21 in response to the rotation of the motor 22.

[0013] The moving body 3 is a vehicle, a robot, or the like that is realized using known technology.

[0014] The antenna 11 is an antenna mounted on the mobile object 3, which receives radio waves from a satellite for satellite positioning. The antenna 11 transmits the radio waves received from the satellite to the positioning unit 12.

[0015] The positioning unit 12 calculates the positioning result and the positioning accuracy based on the radio waves received by the antenna 11. The positioning unit 12 is a general positioning device, and may be any device capable of performing positioning using the radio waves received by the antenna 11 and acquiring the position information (positioning result) of the moving object 3 and the accuracy of the position information (positioning accuracy). The positioning unit 12 realizes positioning using a known technology, and examples of the positioning method include, but are not limited to, single positioning, DGPS (Differential Global Positioning System), RTK-GPS (Real-Time Kinematic Global Positioning System), etc. Furthermore, when DGPS, RTKGPS, etc. are used, the positioning unit 12 is provided with a receiving device for receiving correction information required for these positioning methods. Furthermore, examples of the accuracy of the position information include, for example, the number of visible satellites, HDOP (Horizontal Dilution of Precision), VDOP (Vertical Dilution of Precision), etc., but it may be any device having a function for determining the goodness of the conditions when receiving radio waves from satellites without relying on these indices. Here, the quality of the reception state may be displayed by a character string such as "This radio wave is / is not due to multipath", "Good accuracy is / is not obtained", etc. The positioning unit 12 may have a multipath detection function. The positioning unit 12 transmits the calculated positioning accuracy and the positioning result to the control unit 15.

[0016] Antenna position change unit 13 changes the position of antenna 11 based on an instruction transmitted from control unit 15. As shown in Fig. 2, antenna position change unit 13 has an arm 21 having antenna 11 mounted at one end and the other end joined to a motor 22, and motor 22 mounted at the center of moving body 3, and changes the position of antenna 11 in the horizontal direction according to the rotation of motor 22.

[0017] 3, antenna position change unit 13 may have a mechanism that has a plurality of arms 21a, 21b, 21c and a plurality of motors 22a, 22b, 22c and changes the position of antenna 11 in three-dimensional directions in response to the rotation of motor 22. By being provided with this mechanism, antenna position change unit 13 can change the antenna height to a position that blocks radio waves or reduces the effects of multipath.

[0018] The antenna position detection unit 14 detects the relative position of the antenna 11 with respect to the moving object 3 after the antenna position change unit 13 changes the position of the antenna 11. As shown in FIG. 2, the antenna position detection unit is disposed below the motor 22 and is joined to the motor 22. The antenna position detection unit 14 is a rotary encoder, and detects the angle of the motor 22 and detects a relative change in the position of the antenna 11 based on the length of the arm 21 that is stored in advance. In other words, if the length of the arm 21 is r, the relative position (X, Y) of the antenna 11 with respect to the center position of the moving object 3 is obtained by the following equations (1) and (2). The antenna position detection unit 14 transmits the relative position to the control unit 15.

number

[0019] The control unit 15 controls the position of the antenna 11, and determines the position of the moving object 3 based on the positioning result and the relative position when the positioning accuracy is equal to or higher than the threshold. The control unit 15 determines the position of the moving object 3 by subtracting the relative position detected by the antenna position detection unit 14 from the positioning result calculated by the positioning unit 12. The threshold is a reference value for determining a position where the positioning accuracy is good.

[0020] For example, when the control unit 15 causes the antenna position change unit 13 to change the motor 22 from 0° to 360° by 1° at intervals of 0.1 seconds, 360 positioning results and relative positions corresponding to the change by 1° are acquired. The positioning accuracy calculated based on the 360 ​​positioning results and relative positions is compared to determine the position where the positioning accuracy is equal to or higher than a predetermined threshold. The position where the positioning accuracy is equal to or higher than a predetermined threshold may be the position where the positioning accuracy is the highest. However, the time interval or angle width of the change is not limited to this. That is, the control unit 15 determines the position where the positioning accuracy is the highest, and then moves the antenna 11 to that position using the antenna position change unit 13. In this way, the control unit 15 may change the motor from 0° to 360° by a predetermined angle, and determine the position of the moving body based on the positioning result and relative position when the positioning accuracy is the highest.

[0021] According to the present disclosure, when the moving body 3 is stationary, it is possible to realize good positioning by changing the position of the antenna 11 so that the radio wave reception state of the antenna 11 becomes good. For example, assume that good positioning is realized when the number of visible satellites (referring to the number of satellites that can receive radio waves as direct waves) is 30. As shown in FIG. 4, when the antenna 11 is in the position shown by the solid line, the radio waves from the satellite 4 are blocked by an obstacle 5 such as a building, and the antenna 11 cannot receive the direct wave 6 from the satellite 4, resulting in a decrease in the number of visible satellites by one. However, when the position of the antenna 11 is changed by 180° to the position shown by the dashed line, the antenna 11 can receive the direct wave 6 from the satellite 4, and the positioning unit 12 can maintain good positioning without reducing the number of visible satellites.

[0022] 4, when antenna 11 is in the position shown by the solid line, it may receive reflected waves 7 (multipath), and when antenna 11 is in the position shown by the dashed line, it may receive direct waves 6. In such a situation, if positioning unit 12 has a multipath detection function, it will determine by the detection function that "the radio waves are reflected waves 7" when antenna 11 is in the position shown by the solid line, and that "the radio waves are direct waves 6" when antenna 11 is in the position shown by the dashed line, and by moving antenna 11 to the position shown by the dashed line, good positioning can be achieved.

[0023] In this way, the positioning device 1 changes the position of the antenna 11 using the antenna position changing unit 13, determines the position of the antenna 11 to be changed based on the positioning accuracy calculated by the positioning unit 12, and determines the position of the moving body 3 based on the positioning result calculated by the positioning unit 12 and the position of the antenna 11 detected by the antenna position detection unit 14.

[0024] FIG. 5 is a flowchart showing an example of a positioning method executed by the positioning device 1.

[0025] In step S101, the antenna 11 receives radio waves from the satellite 4.

[0026] In step S102, the positioning unit 12 calculates the positioning result and the positioning accuracy.

[0027] In step S103, the control unit 15 determines the position of the antenna 11 to be changed.

[0028] In step S104, the antenna position changing unit 13 changes the position of the antenna 11.

[0029] In step S105, the antenna position detection unit 14 detects the relative position of the antenna 11 with respect to the moving object 3 after the position of the antenna 11 has been changed.

[0030] In step S106, the control unit 15 determines whether the positioning accuracy at the changed position of the antenna 11 is equal to or greater than a threshold value.

[0031] In step S107, the antenna position change unit 13 moves the antenna 11 to a position where the positioning accuracy becomes equal to or greater than a threshold value.

[0032] By performing such processing, the positioning device 1 according to the present disclosure receives radio waves while reducing the effects of radio wave blocking and multipath, thereby achieving good positioning.

[0033] Second embodiment Next, an example of determining the position of an antenna while a moving object is moving will be described as a second embodiment. FIG. 6 is a block diagram showing an example of the configuration of a positioning device 2 according to the second embodiment. The positioning device 2 shown in FIG. 6 includes an antenna 11, a positioning unit 12, an antenna position changing unit 13, an antenna position detection unit 14, a control unit 15, and a speedometer unit 16. The positioning device 2 differs from the positioning device 1 according to the first embodiment in that it further includes the speedometer unit 16. The same configurations as those in the first embodiment are given the same reference numbers as those in the first embodiment, and descriptions thereof will be omitted as appropriate.

[0034] The speed measurement unit 16 is provided inside the moving body 3 and measures the speed at which the moving body 3 moves. The speed measurement unit 16 transmits the measured moving speed of the moving body 3 to the control unit 15. The control unit 15 determines the speed at which the antenna position change unit 13 changes the position of the antenna 11 based on the moving speed, and instructs the antenna position change unit 13 to change the position of the antenna 11. For example, when the moving body 3 moves in a certain direction at a speed of 1 m / sec, the antenna position change unit 13 rotates the motor 22 (i.e., the antenna 11) at a speed faster than the moving speed of the moving body 3, such as 5 rotations / sec, thereby making it possible to sufficiently search for an antenna position at which the positioning accuracy is improved.

[0035] FIG. 7 is a flowchart showing an example of a positioning method executed by the positioning device 2.

[0036] In step S201, the antenna 11 receives radio waves from the satellite 4.

[0037] In step S202, the speedometer unit 16 measures the moving speed of the moving object 3.

[0038] In step S203, the positioning unit 12 calculates the positioning result and the positioning accuracy.

[0039] In step S204, the control unit 15 determines the position of the antenna 11 to be changed and the speed at which the position of the antenna 11 is changed.

[0040] In step S205, the antenna position changing unit 13 changes the position of the antenna 11.

[0041] In step S206, the antenna position detection unit 14 detects the relative position of the antenna 11 with respect to the moving object 3 after the position of the antenna 11 has been changed.

[0042] In step S207, the control unit 15 determines whether the positioning accuracy at the changed position of the antenna 11 is equal to or greater than a threshold value.

[0043] In step S208, the antenna position change unit 13 moves the antenna 11 to a position where the positioning accuracy becomes equal to or greater than a threshold value.

[0044] By performing such processing, the positioning device 2 according to the present disclosure can receive radio waves while reducing the effects of radio wave blocking and multipath, even when the mobile object 3 is moving, thereby achieving good positioning.

[0045] The following supplementary notes are further disclosed regarding the above embodiment.

[0046] (Additional note 1) A positioning device for detecting a position of a moving object, a control unit that receives radio waves from a satellite, calculates a positioning result and a positioning accuracy based on the received radio waves, changes a position of an antenna, detects a relative position of the antenna with respect to the moving body after the position of the antenna is changed, controls a position of the antenna, and determines a position of the moving body based on the positioning result and the relative position when the positioning accuracy is equal to or greater than a threshold value. A positioning device comprising: (Additional note 2) The control unit is 2. The positioning device according to claim 1, further comprising a motor, and the position of the antenna is changed in the horizontal direction in response to rotation of the motor. (Additional note 3) The control unit is 3. The positioning device according to claim 2, wherein the motor is changed by a predetermined angle from 0° to 360° and the position of the moving body is determined based on the positioning result and the relative position when the positioning accuracy is highest. (Additional note 4) The control unit is 2. The positioning device according to claim 1, further comprising a plurality of motors, and changing a position of the antenna in three dimensions in response to rotation of the motors. (Additional note 5) The control unit is 5. The positioning device according to claim 1, further comprising: a measuring unit configured to measure a speed at which the moving object moves; and a speed at which the position of the antenna is changed based on the measuring speed. (Additional note 6) A method for detecting a position of a moving object, comprising: By the positioning device, A positioning method comprising the steps of: receiving radio waves from a satellite; calculating a positioning result and positioning accuracy based on the received radio waves; changing an antenna position; detecting a relative position of the antenna with respect to the moving body after changing the antenna position; and controlling the position of the antenna, and determining the position of the moving body based on the positioning result and the relative position when the positioning accuracy is equal to or greater than a threshold value.

[0047] Although the above-mentioned embodiment has been described as a representative example, it is obvious to those skilled in the art that many modifications and substitutions can be made within the spirit and scope of the present disclosure. Therefore, the present invention should not be interpreted as being limited by the above-mentioned embodiment, and various modifications or changes can be made without departing from the scope of the claims. For example, it is possible to combine multiple building blocks shown in the configuration diagram of the embodiment into one, or to divide one building block. [Explanation of symbols]

[0048] 1, 2 Positioning device 3. Mobile 4 satellites 5. Obstacles such as buildings 11 Antenna 12 Positioning unit 13 Antenna position change section 14 Antenna position detector 15 Control section 16 Speed ​​measurement section 21, 21a, 21b, 21c Arms 22, 22a, 22b, 22c Motor

Claims

1. A positioning device for detecting a position of a moving object, An antenna mounted on a moving object for receiving radio waves from a satellite; A speed measurement unit that measures a moving speed of the moving object; a positioning unit that calculates a positioning result and a positioning accuracy based on the radio waves received by the antenna; an antenna position change unit that changes the position of the antenna; an antenna position detection unit that detects a relative position of the antenna with respect to the moving object after the position of the antenna is changed; a control unit that determines a speed at which the antenna position changing unit changes the position of the antenna based on the moving speed, and determines a position of the moving object based on the positioning result and the relative position when the positioning accuracy is equal to or greater than a threshold; A positioning device comprising:

2. The positioning device according to claim 1 , wherein the antenna position changer has a motor and changes the position of the antenna in the horizontal direction in response to rotation of the motor.

3. 3. The positioning device according to claim 2, wherein the control unit changes the motor by a predetermined angle from 0° to 360° and determines the position of the moving body based on the positioning result and the relative position when the positioning accuracy is highest.

4. The positioning device according to claim 1 , wherein the antenna position changer has a plurality of motors and changes the position of the antenna in three dimensional directions in response to rotation of the motors.

5. A positioning method for a positioning device that detects the position of a moving object, comprising: By the positioning device, receiving radio waves from a satellite; Measuring a speed at which the moving object moves; calculating a positioning result and a positioning accuracy based on the received radio waves; determining a speed at which to change the position of the antenna based on the speed of movement; Varying the position of the antenna; detecting a relative position of the antenna with respect to the moving object after changing the position of the antenna; determining a position of the moving object based on the positioning result and the relative position when the positioning accuracy is equal to or greater than a threshold; A positioning method including:

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