Method for positioning vehicle in tunnel

Abstract

The invention provides a method for positioning a vehicle in a tunnel, and the method comprises the steps: installing a speed sensor and a wireless card reader on a vehicle, and installing a passive tag on one side wall of the tunnel; the wireless card reader reads the serial number of the passive tag, the speed sensor calculates the real-time vehicle speed, and positioning calculation is carried out according to the received serial number of the passive tag and the real-time vehicle speed. Wherein the label travel s1 is calibrated through the label number b and the label travel proportionality coefficient lambda, the stage travel s2 is calculated through the vehicle speed v and the stage formation time t, and the travel s of the vehicle in the tunnel can be obtained through s1 + s2, namely the final required result. According to the method, the specific length of the vehicle in the tunnel can be calculated according to the serial number, read by the wireless card reader, of the passive tag and the real-time vehicle speed calculated by the speed sensor, and therefore positioning of the vehicle in the tunnel is achieved.

Description

Technical Field

[0001] The invention relates to a positioning method, in particular to a vehicle positioning method in a tunnel. Background Art

[0002] During tunnel construction, because the tunnel is too narrow and long, safety is particularly important when vehicles move inside. Knowing the exact position of the vehicle in the tunnel in real time is the first step in overall monitoring of the vehicle.

[0003] The Chinese patent document with the publication number CN117308934A discloses a technology named "a method, device, equipment and storage medium for lane-level positioning in a tunnel". The method in the technology includes: obtaining at least one of GNSS positioning information, INS positioning information, V2X air interface positioning information and roadside positioning information of a roadside sensing device; determining the vehicle position information according to at least one of GNSS positioning information, INS positioning information, first fusion positioning information of roadside positioning information and V2X air interface positioning information and second fusion positioning information of roadside positioning information and INS positioning information, and performing lane matching in combination with map information to obtain lane-level positioning information. By combining the positioning information of multiple existing positioning systems to perform positioning preferentially, especially by multiplexing the fusion positioning of V2X and INS with roadside sensing devices, the problem that vehicles cannot perform high-precision lane-level positioning in medium and long tunnels is solved, and the high cost of high-precision equipment is avoided.

[0004] However, satellite positioning technology cannot be used alone due to the characteristics of tunnels. Conventional UWB, Bluetooth positioning and other methods are not suitable for use in tunnel construction due to factors such as construction costs and difficult configuration.

[0005] Therefore, it is urgent to find a tunnel positioning method that is both accurate and easy to install. Summary of the invention

[0006] The purpose of the present invention is to provide a method for positioning a vehicle in a tunnel in view of the deficiencies in the prior art.

[0007] A first aspect of the present invention provides a method for positioning a vehicle in a tunnel, comprising: A speed sensor and a wireless card reader are installed on the vehicle, and a passive tag is installed on one side wall of the tunnel; the wireless card reader reads the number of the passive tag; the speed sensor calculates the real-time vehicle speed; when numbering the passive tags, they are numbered in the order of 1, 2, 3, 4...n, and the number of passive tags meets the following conditions: The positioning method is: (1) Calculate the temporary value b of the current passive tag number; Assume that the number value a of the passive tag read by the wireless card reader at any time is assigned to the temporary stored number value b of the passive tag. At this moment, the vehicle starts to move. After that, the temporary stored number value b of the passive tag is calculated as follows: ① If the number value of the passive tag continuously read by the wireless card reader is a, the value of b remains unchanged; ② If the wireless card reader cannot detect the passive tag and has no output, the number value of the passive tag is empty, the value of a is assigned to 0, and the value of b remains unchanged; ③ When the wireless card reader detects the passive tag again, the number value of the passive tag is assigned to a, and the value of a is assigned to b. At the same time, the stage travel time t is updated to 0, and the timing of time t begins; (2) Calculate the value of i in the vehicle's current direction of travel; according to the order in which the passive tags are installed, the direction in which the vehicle moves in the direction where the passive tag number increases is defined as the positive direction, and the value of i is equal to 1; conversely, when the vehicle moves in the direction in which the passive tag number decreases, it is defined as the reverse direction, and the value of i is equal to -1; (3) Calculate the passive tag travel s1 = b*λ; λ is the proportional coefficient between the installation spacing of adjacent numbered passive tags and the number difference; the passive tag travel s1 value remains unchanged when the a value does not jump positively, and is only calculated when the a value jumps positively; (4) Calculate the stage travel s2; When the value of a jumps positively, t starts timing from 0, and the calculation formula of the stage travel s2 is as follows: Where, v is the real-time vehicle speed; (5) Calculate vehicle travel s: The calculated vehicle travel distance s is the specific length of the vehicle in the tunnel.

[0008] Based on the above, the vehicle's traveling direction i value is obtained by: Obtain the current vehicle control direction parameter through the vehicle's electronic control system parameters and assign it to i; or, The direction of the vehicle's travel i value is determined based on the direction of the passive tag number change: when the vehicle moves, when the number value a of the passive tag read by the wireless card reader jumps from 0 to the positive direction, the i value is obtained by comparing the a value with the b value: .

[0009] Based on the above, the direction of change of the passive tag number is used as the basis for determining the vehicle's direction i value, which is only calculated once when the a value jumps positively from 0. No calculation is performed at other times, and the previous i value is used.

[0010] Based on the above, the passive tags are installed at equal intervals on the side walls of the tunnel.

[0011] Based on the above, the speed sensor is installed on the wheel, the wireless card reader is installed on the side of the vehicle, and the installation height of the passive tag is at the same level as the wireless card reader.

[0012] A second aspect of the present invention provides a vehicle positioning system in a tunnel, characterized by comprising: Passive tags are installed on one side of the tunnel and are numbered in the order of 1, 2, 3, 4, ... n. The number of passive tags must meet the following conditions: Wireless card reader, installed on the vehicle, used to read the number of the passive tag and transmit it to the HMI or PLC; Speed ​​sensor, installed on the vehicle, used to calculate the real-time vehicle speed and transmit it to the HMI or PLC; HMI or PLC, installed on the vehicle, performs positioning calculations based on the received passive tag number and real-time vehicle speed: (1) Calculate the temporary value b of the current passive tag number; Assume that the number value a of the passive tag read by the wireless card reader at any time is assigned to the temporary stored number value b of the passive tag. At this moment, the vehicle starts to move. After that, the temporary stored number value b of the passive tag is calculated as follows: ① If the number value of the passive tag continuously read by the wireless card reader is a, the value of b remains unchanged; ② If the wireless card reader cannot detect the passive tag and has no output, the number value of the passive tag is empty, the value of a is assigned to 0, and the value of b remains unchanged; ③ When the wireless card reader detects the passive tag again, the number value of the passive tag is assigned to a, and the value of a is assigned to b. At the same time, the stage travel time t is updated to 0, and the timing of time t begins; (2) Calculate the value of i in the vehicle's current direction of travel; according to the order in which the passive tags are installed, the direction in which the vehicle moves in the direction where the passive tag number increases is defined as the positive direction, and the value of i is equal to 1; conversely, when the vehicle moves in the direction in which the passive tag number decreases, it is defined as the reverse direction, and the value of i is equal to -1; (3) Calculate the passive tag travel s1 = b*λ; λ is the proportional coefficient between the installation spacing of adjacent numbered passive tags and the number difference; the passive tag travel s1 value remains unchanged when the a value does not jump positively, and is only calculated when the a value jumps positively; (4) Calculate the stage travel s2; When the value of a jumps positively, t starts timing from 0, and the calculation formula of the stage travel s2 is as follows: Where, v is the real-time vehicle speed; (5) Calculate vehicle travel s: The calculated vehicle travel distance s is the specific travel distance of the current vehicle, and the specific travel distance of the current vehicle is the specific length of the vehicle in the tunnel.

[0013] The present invention has the following beneficial effects and advantages: (1) The method of the present invention can calculate the specific length of the vehicle in the tunnel according to the serial number of the passive tag read by the wireless card reader and the real-time vehicle speed calculated by the speed sensor, thereby realizing the positioning of the vehicle in the tunnel.

[0014] (2) The system of the present invention only needs to be equipped with a wireless card reader, a passive tag, a speed sensor and an HMI or PLC to realize the positioning of the vehicle in the tunnel. It has a simple structure, is easy to implement and maintain, and solves various problems of traditional tunnel positioning. In addition, the cost of passive tags is extremely low. If damaged, only the passive tag with the same number needs to be replaced at the same location. Therefore, the cost is much lower than UWB and Bluetooth positioning.

[0015] (3) The positioning accuracy of the present invention depends on the HMI or PLC (HMI) calculation cycle, speed sensor accuracy, passive tag installation accuracy and distance. The hardware selection can be carried out according to the specific usage scenario. According to the accuracy of conventional hardware, the positioning accuracy can be controlled within ±5cm.

[0016] (4) For abnormal situations such as sudden change in vehicle speed, system power failure and restart, and local passive tag damage, the present invention will only cause temporary and local positioning loss. After the wireless card reader rescans the passive tag, it will recalibrate the position. Therefore, the present invention has excellent robustness and wide adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a system block diagram of the present invention.

[0018] Figure 2 It is a schematic diagram of the hardware installation position of the system of the present invention.

[0019] Figure 3 It is a schematic diagram of passive tag installation and scanning in the present invention. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0021] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may include steps or units that are not listed.

[0022] To facilitate understanding of the technical solutions provided by the present application, the technical terms involved in the embodiments of the present application are explained below.

[0023] This application has the following parameters (parameter units are in brackets): Tag number value a: The tag number read by the card reader. The string type number needs to be converted into a numeric type through HMI or PLC (HMI) for easy calculation. When the card reader signal does not cover the passive tag, the value a is set to 0. Label travel ratio coefficient λ: the ratio between the installation spacing (m) of labels with adjacent numbers and the number difference; Temporary storage value b of tag number: When the vehicle moves in the tunnel, the card reader and the passive tag signal coverage range need to meet certain requirements. The card reader reads the tag number intermittently, so it is necessary to temporarily store the card number and record it as temporary storage value b; when the card reader can read the tag, the value is the same as a. When the card reader cannot read the tag value, the tag value remains unchanged at a, in preparation for the subsequent travel calculation; Current vehicle speed v (m / s): The current speed of the vehicle. Its value is the actual vehicle speed after being calibrated by the speed sensor. This application can directly obtain accurate vehicle speed information by default, ignoring the calibration process; Vehicle moving direction i: the direction along which the label number increases is 1, and the direction along which the label number decreases is -1; Stage travel time t (s): When the tag number read from the card reader changes, the timing starts and this time is calculated as the integral time of the stage travel; Tag travel s1 (m): The travel calibrated by the tag number b and the tag travel ratio coefficient λ can be used for rough positioning; Stage travel s2 (m): The travel calculated by vehicle speed v and stage formation time t can be used for accurate stage positioning; Vehicle travel s (m): the distance traveled by the vehicle in the tunnel, which is the final desired result; The present application is described in detail below through some embodiments and their application scenarios in conjunction with the accompanying drawings.

[0024] The present embodiment provides a vehicle positioning system in a tunnel, including a speed sensor installed on the vehicle, an HMI or PLC, a wireless card reader hardware, and a passive tag installed on the side wall of the tunnel. The wireless card reader reads the number of the passive tag and transmits it to the HMI or PLC. The speed sensor calculates the real-time vehicle speed and transmits it to the HMI or PLC. The HMI or PLC performs positioning calculations based on the received passive tag number and the real-time vehicle speed: the tag travel s1 is calibrated by the tag number b and the tag travel proportional coefficient λ, and the stage travel s2 is calculated by the vehicle speed v and the stage formation time t, and s1+s2 can obtain the vehicle's travel s in the tunnel.

[0025] like Figure 1-Figure 3 As shown, the speed sensor 1 is installed on the wheel, the wireless card reader 2 is installed on the side of the vehicle, the HMI or PLC 3 is installed at a suitable position of the vehicle 4, and the passive tag 5 is installed on the side wall of the tunnel 6.

[0026] The following requirements are imposed on the installation of passive tags: Ⅰ. When installing passive tags, install them at equal distances on one side of the tunnel according to the numbers; Ⅱ. When numbering passive tags, they are numbered in the order of 1, 2, 3, 4...n. The number of passive tags must meet the following conditions: Ⅲ. When installing passive tags, the installation height should be at the same level as the wireless card reader as much as possible to ensure that the wireless card reader can read the tag value smoothly when it is close to the passive tag. According to its corresponding characteristics and signal sensing range, the passive tag needs to meet the requirement that the wireless card reader can sense at most one passive tag signal at any time.

[0027] The specific positioning method of the present invention is: (1) Calculate the temporary value b of the current passive tag number; Assume that the number value a of the passive tag read by the wireless card reader at any time is assigned to the temporary stored number value b of the passive tag. At this moment, the vehicle starts to move. After that, the temporary stored number value b of the passive tag is calculated as follows: ① If the number value of the passive tag continuously read by the wireless card reader is a, the value of b remains unchanged; ② If the wireless card reader cannot detect the passive tag and has no output, the number value of the passive tag is empty, the value of a is assigned to 0, and the value of b remains unchanged; ③ When the wireless card reader detects the passive tag again, the number value of the passive tag is assigned to a, and the value of a is assigned to b. At the same time, the stage travel time t is updated to 0, and the timing of time t begins.

[0028] (2) Calculate the value of i in the vehicle's current direction of travel; according to the order in which the passive tags are installed, the direction in which the vehicle moves in the direction where the passive tag number increases is defined as the positive direction, and the value of i is equal to 1; conversely, when the vehicle moves in the direction in which the passive tag number decreases, it is defined as the reverse direction, and the value of i is equal to -1; The vehicle's traveling direction i value can be obtained in the following two ways: Ⅰ. In the vehicle's electronic control system, the HMI or PLC will have the current vehicle control direction parameters (driver's cab control rights, etc.), so the vehicle's direction i value can be directly obtained and assigned through the electrical system parameters; Ⅱ. Determine the vehicle's direction of travel based on the direction of the passive tag number change: When the vehicle moves, when the number value a of the passive tag read by the wireless card reader jumps from 0 to the positive direction, compare the a value and the b value to get the i value: The direction of change of the passive tag number is used as the basis for determining the vehicle's direction i value. It is calculated only once when the a value jumps positively from 0. No calculation is performed at other times, and the previous i value is used.

[0029] (3) Calculate the passive tag travel s1; When the vehicle is moving, the b value will change synchronously with the movement of the vehicle. Therefore, the passive tag travel s1 is calculated as follows: s1=b*λ; wherein, the passive tag travel s1 value remains unchanged when the a value does not jump positively, and is only calculated when the a value jumps positively.

[0030] (4) Calculate the stage travel s2; When the value of a jumps positively, t starts timing from 0, and the calculation formula of the stage travel s2 is as follows: Where v is the real-time vehicle speed.

[0031] (5) Calculate vehicle travel s: The calculated vehicle travel distance s is the specific travel distance of the current vehicle, that is, the specific length positioning of the vehicle in the tunnel.

[0032] In some other exemplary embodiments, a visual positioning display may be performed in an HMI or a PLC based on the calculated vehicle tunnel travel s.

[0033] Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A method for positioning a vehicle in a tunnel, characterized in that: include: Install speed sensors and wireless card readers on vehicles and passive tags on one side of the tunnel wall; The wireless card reader reads the number of the passive tag; the speed sensor calculates the real-time vehicle speed; when the passive tags are numbered, they are numbered in the order of 1, 2, 3, 4...n, and the number of passive tags meets the following conditions: ， The positioning method is: (1) Calculate the temporary value b of the current passive tag number; Assume that the number value a of the passive tag read by the wireless card reader at any time is assigned to the temporary stored number value b of the passive tag. At this moment, the vehicle starts to move. After that, the temporary stored number value b of the passive tag is calculated as follows: ① If the number value of the passive tag continuously read by the wireless card reader is a, the value of b remains unchanged; ② If the wireless card reader cannot detect the passive tag and has no output, the number value of the passive tag is empty, the value of a is assigned to 0, and the value of b remains unchanged; ③ When the wireless card reader detects the passive tag again, the number value of the passive tag is assigned to a, and the value of a is assigned to b. At the same time, the stage travel time t is updated to 0, and the timing of time t begins; (2) Calculate the value of i in the vehicle's current direction of travel; according to the order in which the passive tags are installed, the direction in which the vehicle moves in the direction where the passive tag number increases is defined as the positive direction, and the value of i is equal to 1; conversely, when the vehicle moves in the direction in which the passive tag number decreases, it is defined as the reverse direction, and the value of i is equal to -1; (3) Calculate the passive tag travel s1 = b*λ; λ is the proportional coefficient between the installation spacing of adjacent numbered passive tags and the number difference; the passive tag travel s1 value remains unchanged when the a value does not jump positively, and is only calculated when the a value jumps positively; (4) Calculate the stage travel s2; When the value of a jumps positively, t starts timing from 0, and the calculation formula of the stage travel s2 is as follows: ， Where, v is the real-time vehicle speed; (5) Calculate vehicle travel s: ， The calculated vehicle travel distance s is the specific travel distance of the current vehicle, and the specific travel distance of the current vehicle is the specific length of the vehicle in the tunnel.

2. The method for positioning a vehicle in a tunnel according to claim 1, characterized in that: The vehicle's traveling direction i value is obtained by: Obtain the current vehicle control direction parameter through the vehicle's electronic control system parameters and assign it to i; or, The direction of the vehicle's travel i value is determined based on the direction of the passive tag number change: when the vehicle moves, when the number value a of the passive tag read by the wireless card reader jumps from 0 to the positive direction, the i value is obtained by comparing the a value with the b value: 。 3. The method for positioning a vehicle in a tunnel according to claim 2, characterized in that: The direction of change of the passive tag number is used as the basis for determining the vehicle's direction i value. It is calculated only once when the a value jumps positively from 0. No calculation is performed at other times, and the previous i value is used.

4. The method for positioning a vehicle in a tunnel according to any one of claims 1 to 3, characterized in that: The passive tags are installed at equal intervals on the side walls of the tunnel.

5. The method for positioning a vehicle in a tunnel according to any one of claims 1 to 3, characterized in that: The speed sensor is installed on the wheel, the wireless card reader is installed on the side of the vehicle, and the installation height of the passive tag is at the same level as the wireless card reader.

6. A vehicle positioning system in a tunnel, characterized in that: include: Passive tags are installed on one side of the tunnel and are numbered in the order of 1, 2, 3, 4, ... n. The number of passive tags must meet the following conditions: ， Wireless card reader, installed on the vehicle, used to read the number of the passive tag and transmit it to the HMI or PLC; Speed ​​sensor, installed on the vehicle, used to calculate the real-time vehicle speed and transmit it to the HMI or PLC; HMI or PLC, installed on the vehicle, performs positioning calculations based on the received passive tag number and real-time vehicle speed: (1) Calculate the temporary value b of the current passive tag number; Assume that the number value a of the passive tag read by the wireless card reader at any time is assigned to the temporary stored number value b of the passive tag. At this moment, the vehicle starts to move. After that, the temporary stored number value b of the passive tag is calculated as follows: ① If the number value of the passive tag continuously read by the wireless card reader is a, the value of b remains unchanged; ② If the wireless card reader cannot detect the passive tag and has no output, the number value of the passive tag is empty, the value of a is assigned to 0, and the value of b remains unchanged; ③ When the wireless card reader detects the passive tag again, the number value of the passive tag is assigned to a, and the value of a is assigned to b. At the same time, the stage travel time t is updated to 0, and the timing of time t begins; (2) Calculate the value of i in the vehicle's current direction of travel; according to the order in which the passive tags are installed, the direction in which the vehicle moves in the direction where the passive tag number increases is defined as the positive direction, and the value of i is equal to 1; conversely, when the vehicle moves in the direction in which the passive tag number decreases, it is defined as the reverse direction, and the value of i is equal to -1; (3) Calculate the passive tag travel s1 = b*λ; λ is the proportional coefficient between the installation spacing of adjacent numbered passive tags and the number difference; the passive tag travel s1 value remains unchanged when the a value does not jump positively, and is only calculated when the a value jumps positively; (4) Calculate the stage travel s2; When the value of a jumps positively, t starts timing from 0, and the calculation formula of the stage travel s2 is as follows: ， Where, v is the real-time vehicle speed; (5) Calculate vehicle travel s: ， The calculated vehicle travel distance s is the specific length of the vehicle in the tunnel.

7. The vehicle positioning system in a tunnel according to claim 6, characterized in that: The vehicle's traveling direction i value is obtained by: Obtain the current vehicle control direction parameter through the vehicle's electronic control system parameters and assign it to i; or, The direction of the vehicle's travel i value is determined based on the direction of the passive tag number change: when the vehicle moves, when the number value a of the passive tag read by the wireless card reader jumps from 0 to the positive direction, the i value is obtained by comparing the a value with the b value: 。 8. The vehicle positioning system in a tunnel according to claim 7, characterized in that: The direction of change of the passive tag number is used as the basis for determining the vehicle's direction i value. It is calculated only once when the a value jumps positively from 0. No calculation is performed at other times, and the previous i value is used.

9. The vehicle positioning system in a tunnel according to claims 6-8, characterized in that: The passive tags are installed at equal intervals on the side walls of the tunnel.

10. The vehicle positioning system in a tunnel according to claims 6-8, characterized in that: The speed sensor is installed on the wheel, the wireless card reader is installed on the side of the vehicle, and the installation height of the passive tag is at the same level as the wireless card reader.

Images