Apparatus and method for positioning train

Abstract

The train positioning device of the present invention comprises: a tag that performs UWB communication with an anchor installed on the ground and mounted on the train; and a control unit that calculates the distance between the anchor and the tag using information received through the tag, calculates the distance on the track from the last balise the train passed by by applying the distance between the anchor and the tag to a distance conversion function for the anchor, and estimates the position on the track of the train through calculations based on the distance between the anchor and the tag and the distance on the track, wherein the anchor is positioned to be adjacent to the railway track within a predetermined distance for each section of the railway track, the distance conversion function is set for each anchor, and calculates the distance on the track according to the distance between the anchor and the tag for the track positioned within the communication range of the anchor.

Description

Technology Field

[0001] The present invention relates to a train positioning device and method for estimating the position of a train on a track. Background Technology

[0002] Measuring the precise location of a train in subways or tunnels where GPS (Global Positioning System) information is unavailable is a very challenging task. Since Ultra-Wide Band (UWB) has a wide bandwidth that enables precise distance measurement, applying it to train positioning can replace positioning systems such as GPS. A UWB communication device consists of ground anchors and onboard tags, and the distance to each anchor is calculated through the tags. Referring to Fig. 1, position estimation using UWB generally estimates the three-dimensional position by using three or more anchors and estimating the distance between each tag and anchor through triangulation.

[0003] There are two major problems with this method.

[0004] First, installation and maintenance costs increase because a large number of anchors are required. As the name suggests, the triangulation method requires at least three anchors for positioning, so it requires higher installation and maintenance costs compared to other sensors. Considering the maximum measurement distance of 150m for recent UWB anchors, at least nine anchors must be installed along a 1km line as shown in Figure 2, which leads to increased installation and maintenance costs.

[0005] Second, the installation conditions are complex due to the narrow positioning area. Since the positioning area of ​​the triangulation method is formed by the intersection of the maximum distance measurement areas of three anchors, the selection of anchor locations is important to ensure positioning in the desired track area, but problems arise where selecting anchor locations becomes very difficult due to existing structures.

[0006] Therefore, technology is required to overcome these problems. The problem to be solved

[0007] The present invention has the technical objective of providing a train positioning device and method that estimate the position of a train on a track through a distance conversion function that calculates the distance on the track based on the distance between an anchor and a tag, in order to solve the aforementioned problems.

[0008] However, the technical problems that this embodiment aims to solve are not limited to the technical problems described above, and other technical problems may exist. means of solving the problem

[0009] As a technical means for solving the aforementioned technical problem, a UWB (Ultra-Wide Band) based train positioning device according to one embodiment of the present invention comprises: a tag that performs UWB communication with an anchor installed on the ground and mounted on a train; and a control unit that calculates the distance between the anchor and the tag using information received through the tag, calculates the distance on the track from the balise that the train last passed by applying the distance between the anchor and the tag to a distance conversion function for the anchor, and estimates the position on the track of the train through calculations based on the distance between the anchor and the tag and the distance on the track, wherein the anchor is positioned to be adjacent to the railway track within a predetermined distance for each section of the railway track, the distance conversion function is set for each anchor, and calculates the distance on the track according to the distance between the anchor and the tag for the track positioned within the communication range of the anchor.

[0010] Additionally, a UWB (Ultra-Wide Band) based train positioning method according to another embodiment of the present invention comprises: a step of calculating the distance between an anchor installed on the ground and a tag using information received through a tag that is mounted on the train and performs UWB communication; a step of calculating the distance on the track from the last balise the train passed by by applying the distance between the anchor and the tag to a distance conversion function for the anchor; and a step of estimating the position on the track of the train through calculations based on the distance between the anchor and the tag and the distance on the track, wherein the anchor is positioned to be adjacent to the railway track within a predetermined distance for each section of the railway track, the distance conversion function is set for each anchor, and for the track positioned within the communication range of the anchor, the distance on the track is calculated according to the distance between the anchor and the tag. Effects of the invention

[0011] According to the means for solving the problem of the present invention described above, the position of a train can be estimated using a single anchor through a distance conversion function set at each anchor, thereby reducing the number of anchors installed compared to existing train positioning methods.

[0012] In addition, high accuracy can be achieved at a low cost by utilizing UWB communication technology. Brief explanation of the drawing

[0013] Figures 1 and 2 are exemplary diagrams illustrating a conventional method for estimating the position of a train. FIG. 3 is a conceptual diagram schematically illustrating a train positioning device according to one embodiment of the present invention. FIG. 4 is an illustrative diagram for explaining the operation of a train positioning device according to an embodiment of the present invention. Figure 5 is an example graph showing the distance transformation function. Figures 6 to 8 are example diagrams for explaining the process of generating a distance transformation function. FIG. 9 is a flowchart illustrating a train positioning method according to an embodiment of the present invention. Specific details for implementing the invention

[0014] The present invention will be described in detail below with reference to the attached drawings. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein. Furthermore, the attached drawings are intended only to facilitate understanding of the embodiments disclosed in this specification, and the technical concept disclosed in this specification is not limited by the attached drawings. In order to clearly explain the present invention in the drawings, parts unrelated to the explanation have been omitted, and the size, form, and shape of each component shown in the drawings may be varied in various ways. Identical or similar parts throughout the specification are denoted by identical or similar reference numerals.

[0015] Suffixes such as "module" and "part" for components used in the following description are assigned or used interchangeably solely for the sake of ease of drafting the specification, and do not inherently possess distinct meanings or roles. Furthermore, in describing the embodiments disclosed in this specification, detailed descriptions of related prior art have been omitted where it is determined that such detailed descriptions could obscure the essence of the embodiments disclosed in this specification.

[0016] Throughout the specification, when it is stated that a part is "connected (connected, contacted, or coupled)" to another part, this includes not only cases where they are "directly connected (connected, contacted, or coupled)," but also cases where they are "indirectly connected (connected, contacted, or coupled)" with other members interposed therebetween. Furthermore, when it is stated that a part "includes (provides, or provides)" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but rather allows for additional "included (provided, or provided)" of other components.

[0017] Terms indicating ordinal numbers, such as first, second, etc., used in this specification are used solely for the purpose of distinguishing one component from another and do not limit the order or relationship of the components. For example, the first component of the present invention may be named the second component, and similarly, the second component may be named the first component.

[0018] FIG. 3 is a conceptual diagram schematically showing a train positioning device according to one embodiment of the present invention, and FIG. 4 is an illustrative diagram for explaining the operation of a train positioning device according to one embodiment of the present invention.

[0019] A train positioning device (100) according to an embodiment of the present invention will be described with reference to FIGS. 3 and 4. The train positioning device (100) includes a tag (110) and a control unit (120).

[0020] The tag (110) is mounted on the train (10) and performs Ultra-Wide Band (UWB) communication with an anchor (200) installed on the ground. Here, the anchor (200) is positioned so as to be adjacent to the railway track (20) within a predetermined distance, with one anchor (200) for each section of the railway track (20).

[0021] The control unit (120) calculates the distance R between the anchor (200) and the tag (110) using information received through the tag (110), calculates the distance on the track from the last balise (30) that the train (10) passed through by applying the distance between the anchor (200) and the tag (110) to a distance conversion function for the anchor (200), and estimates the position on the track of the train (10) through calculations based on the distance between the anchor (200) and the tag (110) and the distance on the track.

[0022] Here, the tag (110) can receive identification information of the anchor (200) from the anchor (200). A distance conversion function is set for each anchor (200) and calculates a line distance S for the distance between the anchor (200) and the tag (110) for a line (20) placed within the communication range (210) of the anchor (200). The line distance is based on the balise (30), and the line distance S at the balise (30) is 0.

[0023] Specifically, the distance conversion function is the distance R to the nearest point (21) of the track (20) that is closest to the distance between the anchor (200) and the track (20). c and the track length S to the nearest point (21). c Based on this, the change in the track distance S is shown according to the distance R between the anchor (200) and the tag (110), and when the distance R between the anchor (200) and the tag (110) is input, the corresponding track distance S is calculated.

[0024] FIG. 5 is an example graph showing a distance conversion function, with the distance R at the closest point (21) c and the track length S to the nearest point (21). c It represents a symmetrical structure based on the nearest point (21). This is because there are two points where the distance R between the anchor (200) and the tag (110) is the same based on the nearest point (21).

[0025] To explain the process of generating such a distance conversion function, the distance conversion function can be generated by using curvature data of the track (20) or by generating it through actual measurement.

[0026] First, the method of generating using curvature data consists of the following steps: calculating coordinate and direction information on a predetermined point on the track (20) using the curvature data of the track (20) and information regarding the nearest point (21); calculating the distance between the tag (110) and the anchor (200) using the coordinate and direction information on the track; and matching the calculated distance between the tag (110) and the anchor (200) with the distance on the track. Here, the information regarding the nearest point is the distance R from the anchor (200) to the nearest point (21). c The track distance S from the ballast (30) to the nearest point (21). c It may include.

[0027] Figure 6 is an example diagram illustrating a method for generating a distance transformation function using curvature data. A method for generating a distance transformation function using curvature data is explained with reference to Figure 6.

[0028] In the process of calculating coordinate and direction information on the track, the coordinate and direction information on the track is, , , It is calculated through Mathematical Formula 1, which has the variable set as the initial condition. Here, is the direction of travel of the train at the nearest point on the track where the distance between the anchor and the tag is minimum, and and is the x and y coordinate values ​​at the nearest point.

[0029] [Mathematical Formula 1]

[0030]

[0031]

[0032]

[0033] In mathematical formula 1 is the angle with respect to the direction of travel of the train at a point on the track at a distance s, and and is the x and y coordinate values ​​of a specified point, and is the curvature value for a given point. The calculated coordinate and direction information is the train's direction of travel, x coordinate, and y coordinate matched to a point at a distance of S on the track.

[0034] The process of calculating the distance between the tag (110) and the anchor (200) using the calculated coordinate and direction information on the track is as follows: S = S c , It is calculated through Mathematical Equation 2, which has variables set to = 0, x = 0, and y = 0 as initial conditions. Here, S is the distance along the track, and S c is the distance on the track from the nearest point, and x and y are the coordinate values ​​at the nearest point.

[0035] [Mathematical Formula 2]

[0036]

[0037] Referring to Fig. 7, in Equation 2, R is the distance between the anchor and the tag, and D t is the distance between the center of the track and the tag, and D c is the distance between the center of the track and the anchor, and H t is the installation height of the tag from the ground, and H a is the installation height of the anchor from the ground.

[0038] In mathematical equation 2, S, The operation is repeated while increasing x and y, and a distance conversion function is generated by matching the distance R between the anchor and the tag calculated for each iteration with the track distance S.

[0039] Next, with reference to FIG. 8, a method of generating through actual measurement is described. The method of generating through actual measurement generates a distance conversion function using data obtained by measuring the distance on the track and the distance between the tag and the anchor using actual measurement equipment (300) which includes a tag (310) that performs UWB communication, an odometer (320) that measures the distance according to movement, and a balise detector (330).

[0040] The control unit (120) estimates the current position of the train using the distance conversion function generated in this way. The control unit (120) estimates the current position of the train using the anchor (200) information received by the tag (110) and the distance conversion function corresponding to the identification number of the anchor (200).

[0041] Referring to FIG. 4, the operation of estimating the current position of the train is described in detail as follows: the control unit (120) calculates the distance between the tag (110) and the anchor (200) at the current time, and calculates the distance on the track of the train (10) at the current time by applying the distance between the tag (110) and the anchor (200) at the current time to the distance conversion function set on the anchor (200) currently communicating.

[0042] Afterwards, the train's current position is estimated by calculating the train's track travel distance through calculations using the distance between the tag (110) and the anchor (200) at the current time point, the distance between the tag (110) and the anchor (200) at the previous time point, the train's track distance at the current time point, and the track distance from the anchor (200) to the nearest point (21).

[0043] The control unit (120) calculates the train's travel distance on the track using mathematical formula 3.

[0044] [Mathematical Formula 3]

[0045]

[0046] is the train's current distance traveled on the track, and is the track distance from the nearest point, and is the distance between the tag and the anchor at the current point in time, and is the anchor's distance transformation function, and is the anchor's identification number.

[0047] Here, the control unit (120) is the distance between the tag (110) and the anchor (200) at the current time. and the distance between the tag (110) and the anchor (200) at the previous point in time Depending on the sign of the difference value The position of the train (10) can be estimated by specifying the distance S of the train on the track at the current time, which is the value.

[0048] As previously explained, the distance conversion function is formed in a symmetrical shape with respect to the nearest point (21), depending on the distance R between the anchor (200) and the tag (110). Two values ​​can be calculated. Referring to FIG. 4, when the train (10) is traveling at a first position (22) and the distance between the anchor (200) and the tag (110) is R, applying R to the distance conversion function can calculate two track distances S for the first point (22) and the second point (23). Referring to FIG. 5, it can be confirmed that the first point (22) and the second point (23) correspond when the distance between the anchor (200) and the tag (110) is R.

[0049] Therefore, the distance between the tag (110) and the anchor (200) at the current point in time and the distance between the tag (110) and the anchor (200) at the previous point in time By calculating the difference, a point can be identified based on the sign of the difference value. Referring to FIG. 5, at the first point (22), the sign of the difference value for the distance between the previous point and the current point is negative, and at the second point (23), the sign of the distance difference value is positive. Accordingly, if the sign of the distance difference value between the current point and the previous point is negative, it can be identified as the first point (22), and if the sign of the distance difference value is positive, it can be identified as the second point (23).

[0050] When the current location of such a train (10) is determined, according to the sign of the difference in distance between the current time point and the previous time point in mathematical formula 3 Since the sign of the value is determined, the distance on the track at the nearest point at The current travel distance of the train (10) can be calculated by the difference in value.

[0051] In this embodiment, the control unit (120) may be implemented in the form of a microprocessor, a central processing unit (CPU), a processor core, a multiprocessor, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), etc., but the scope of the present invention is not limited thereto.

[0052] The train interval estimation device (100) may further include a database (130). The database (130) may store data required to perform an operation to estimate the position of the train, such as a distance conversion function set at each anchor.

[0053] FIG. 9 is a flowchart illustrating a train positioning method according to an embodiment of the present invention.

[0054] Referring to FIGS. 3, 4, and 9, a method for estimating train spacing (S100) according to an embodiment of the present invention is described as follows: the train positioning method (S100) calculates the distance between an anchor (200) installed on the ground and a tag (110) using information received through a tag (110) that is mounted on the train and performs UWB communication (step S110), calculates the distance on the track from the last ballast (30) that the train (10) passed through by applying the distance between the anchor (200) and the tag (110) to a distance conversion function set on the anchor (200) (step S120), and then estimates the position on the track of the train (step S130) through calculations using the calculated distance between the anchor (200) and the tag (110) and the distance on the track. Here, the anchor (200) is positioned so as to be adjacent to the railway track within a predetermined distance for each section of the railway track, and the distance conversion function is set for each anchor (200), and for the track (20) positioned within the communication range of the anchor (200), the distance on the track between the anchor (200) and the tag (110) is calculated.

[0055] The distance conversion function can be generated by using the curvature data of the track (20) and by using actual measurements.

[0056] First, the method of generating using curvature data is composed of the following steps: calculating coordinate and direction information on a predetermined point on a track (20) using the curvature data of the track (20) and the distance S on the track; calculating the distance between a tag (110) and an anchor (200) using the coordinate and direction information on the track; and matching the calculated distance between the tag (110) and the anchor (200) with the distance on the track.

[0057] And, the method of generating through actual measurement generates a distance conversion function using data obtained by actually measuring the distance between the tag and the anchor and the distance on the track using actual measurement equipment (300) including a tag (310) that performs UWB communication as in FIG. 8, an odometer (320) that measures the distance according to movement, and a balise detector (330).

[0058] Next, the process of estimating the position of the train on the track (step S130) is explained in detail.

[0059] The control unit (120) estimates the current position of the train by calculating the train's track travel distance through calculations using the distance between the tag and the anchor at the current time point, the distance between the tag and the anchor at the previous time point, the track distance at the current time point, and the track distance to the nearest point on the track where the distance between the anchor and the tag is minimum.

[0060] Specifically, the control unit (120) calculates the train's travel distance on the track using mathematical formula 3.

[0061] [Mathematical Formula 3]

[0062]

[0063] is the train's current distance traveled on the track, and is the track distance from the nearest point, and is the distance between the tag and the anchor at the current point in time, and is the anchor's distance transformation function, and is the anchor's identification number.

[0064] Here, the control unit (120) is the distance between the tag (110) and the anchor (200) at the current time. and the distance between the tag (110) and the anchor (200) at the previous point in time Depending on the sign of the difference value The position of the train (10) can be estimated by specifying the distance S of the train on the track at the current time, which is the value.

[0065] The present invention may also be embodied in the form of a recording medium comprising computer-executable instructions, such as program modules executed by a computer. A computer-readable medium may be any available medium accessible by a computer and includes both volatile and non-volatile media, and both removable and non-removable media. Additionally, a computer-readable medium may include a computer storage medium. A computer storage medium includes both volatile and non-volatile, removable and non-removable media, implemented by any method or technique for storing information such as computer-readable instructions, data structures, program modules, or other data.

[0066] Additionally, although the method and system of the present invention have been described in relation to specific embodiments, some or all of their components or operations may be implemented using a computer system having a general-purpose hardware architecture.

[0067] A person skilled in the art to which the present invention pertains will understand that, based on the foregoing description, modifications can be easily made to other specific forms without altering the technical spirit or essential features of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims set forth below, and all modifications or variations derived from the meaning and scope of the claims and equivalent concepts should be interpreted as being included within the scope of the present invention.

[0068] The scope of the present invention is defined by the claims set forth below rather than by the detailed description above, and all modifications or variations derived from the meaning and scope of the claims and the concept of equivalents thereof should be interpreted as being included within the scope of the present invention. Explanation of the symbols

[0069] 100: Train positioning device 110: Tag 120: Control unit

Claims

Claim 1 In a UWB (Ultra-Wide Band) based train positioning device, a tag mounted on a train and performing UWB communication with an anchor installed on the ground; The system includes a control unit that calculates the distance between the anchor and the tag using information received through the tag, calculates the track distance from the balise the train last passed by by applying the distance between the anchor and the tag to a distance conversion function for the anchor, and estimates the track position of the train through calculations based on the distance between the anchor and the tag and the track distance, wherein the anchor is positioned to be adjacent to the railway track within a predetermined distance for each section of the railway track, the distance conversion function is set for each anchor and calculates the track distance according to the distance between the anchor and the tag for the track positioned within the communication range of the anchor, and the control unit estimates the current position of the train by calculating the train's track travel distance through calculations using the distance between the tag and the anchor at the current time point, the distance between the tag and the anchor at the previous time point, the track distance of the train at the current time point, and the track distance to the nearest point on the track, wherein the nearest point is a point on the track where the distance between the anchor and the track is minimum, the train Positioning device. Claim 2 A train positioning device according to claim 1, wherein the distance transformation function is generated based on the steps of: calculating coordinate and direction information on a predetermined point on a track using track curvature data and information on the nearest point on a track; calculating the distance between a tag and an anchor using the coordinate and direction information on the track; and matching the calculated distance between the tag and the anchor with the distance on the track, wherein the nearest point is a point on the track where the distance between the anchor and the track is minimum, and the nearest point information includes the distance from the anchor to the nearest point and the distance on the track from the balise to the nearest point. Claim 3 In paragraph 2, the coordinate and direction information on the track is, as an initial condition , , It is calculated through the established mathematical formula 1, [Mathematical Formula 1] The above is the direction of travel of the train at the closest point mentioned above, and the and above is the x and y coordinate values ​​at the closest point mentioned above, and the is an angle with respect to the direction of travel of the train at a predetermined point on the above track, and the above and above is the x-coordinate value and y-coordinate value of the above-mentioned predetermined point, and the above A train positioning device, which is a curvature value for the above-mentioned predetermined point. Claim 4 In paragraph 3, the distance between the tag and the anchor is S = S as an initial condition. c , It is calculated through Mathematical Formula 2 with = 0, x = 0, y = 0 set, [Mathical Formula 2] The above S is the distance on the above track, and the above S c is the distance on the track at the closest point, the x and y are coordinate values ​​at the closest point, the R is the distance between the anchor and the tag, and the D t is the distance between the center of the above track and the above tag, and the above D c is the distance between the center of the above track and the above anchor, and the H t is the installation height of the above tag from the ground, and the above H a A train positioning device, which is the installation height of the anchor above from the ground. Claim 5 A train positioning device according to claim 4, wherein the distance conversion function is generated by repeating the mathematical formula 2 while increasing S, x, and y, and matching the distance between the anchor and the tag calculated for each iteration with the track distance. Claim 6 A train positioning device according to claim 1, wherein the distance conversion function is generated using data obtained by measuring the distance on the track and the distance between the tag and the anchor using actual measurement equipment including a tag performing UWB communication, an odometer measuring the distance according to the movement of the train, and a balise detector. Claim 7 delete Claim 8 In paragraph 1, the control unit calculates the track travel distance of the train using Equation 3, [Equation 3] The above is the current travel distance of the above train on the track, and the above is the track distance at the closest point mentioned above, and the above is the distance between the tag and the anchor at the current point in time, and the above is the distance transformation function of the above anchor, and is a train positioning device, which is the identification number of the above anchor. Claim 9 A train positioning device according to claim 1, wherein the anchor is disposed one by one at every predetermined section along the entire track. Claim 10 In a UWB (Ultra-Wide Band) based train positioning method, the method comprises the steps of: calculating the distance between an anchor installed on the ground and a tag using information received through a tag mounted on the train and performing UWB communication; and calculating the track distance from the balise that the train last passed by by applying the distance between the anchor and the tag to a distance conversion function for the anchor. A train positioning method comprising the step of estimating the position on the track of the train through calculations based on the distance between the anchor and the tag and the distance on the track, wherein the anchor is positioned so as to be adjacent to the railway track within a predetermined distance for each section of the railway track, the distance conversion function is set for each anchor and calculates the distance on the track according to the distance between the anchor and the tag for the track positioned within the communication range of the anchor, and the step of estimating the position on the track of the train estimates the current position of the train by calculating the travel distance on the track of the train through calculations using the distance between the tag and the anchor at the current time point, the distance between the tag and the anchor at the previous time point, the distance on the track of the train at the current time point, and the distance on the track to the nearest point, and wherein the nearest point is a point on the track where the distance between the anchor and the track is minimum. Claim 11 A train positioning method according to claim 10, wherein the distance conversion function is generated based on the step of calculating coordinate and direction information on a predetermined point on a track using track curvature data and a distance on the track; the step of calculating the distance between a tag and an anchor using the coordinate and direction information on the track; and the step of matching the calculated distance between a tag and an anchor with the distance on the track. Claim 12 A train positioning method according to claim 10, wherein the distance conversion function is generated using data obtained by measuring the distance on the track and the distance between the tag and the anchor using actual measurement equipment including a tag performing UWB communication, an odometer measuring the distance according to the movement of the train, and a balise detector. Claim 13 delete Claim 14 A non-transient computer-readable recording medium having a computer program recorded thereon for performing a train positioning method according to any one of paragraphs 10 through 12.

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