CN108229628A - Train positioning identification method based on three-dimensional magnetic code - Google Patents

Abstract

The invention discloses a three-dimensional magnetic code-based train positioning identification method. This method uses permanent magnet magnetic 'N' poles, 'S' poles and '0' vacancies to represent the values 2, 1 and 0 respectively, which are combined to form a three-dimensional magnetic code for train positioning information, and then the three-dimensional magnetic code is divided into certain intervals according to the accuracy requirements It is pasted along the track, and the information is read and decoded by the electromagnetic induction reading device installed on the train, so as to obtain the coordinate positioning, as well as the speed and acceleration of the train. In this method, the preset position of the train is coded and combined by three code elements in a matrix sequence, and different code element preset sequences represent different position information. The method involves coding principles, inductive recognition, and rapid decoding and recognition technologies. The most notable feature of this patent is its strong environmental adaptability and good reliability, and it can be used normally in various harsh environments such as dust, poor light, low temperature, rain and snow.

Description

A method for train positioning and identification based on three-dimensional magnetic code

technical field

The present invention relates to technologies such as electromagnetic induction and combined coding, and more specifically relates to a three-dimensional magnetic coding method and its application in the fields of train positioning marks and speed measurement.

Background technique

At present, the maglev train is a new type of transportation developed by the country following the high-speed rail. It has many advantages such as low energy consumption, high speed, strong climbing ability, safety, intelligence, and comfortable ride. development trend. Therefore, as the first choice for the development of a new generation of ground transportation in the future, maglev trains have great strategic significance for social livelihood, economic development, and urban layout.

There are many methods of speed measurement and positioning technology for maglev trains at home and abroad, such as: cross-loop speed measurement and positioning, Doppler radar speed measurement and positioning, microwave speed measurement and positioning, speed measurement and positioning based on inter-track cables, "set distance detection + beacon" speed measurement and positioning, etc. In China, medium and low-speed maglev trains mostly use the cross-loop speed measurement and positioning method. However, the magnetic levitation train is equipped with strong magnetic field subsystems such as suspension system, guidance system and propulsion system, and there is a certain degree of electromagnetic interference among them. The cross-loop speed measurement and positioning method is based on the train position identification of the magnetic field generated by the loop. The electromagnetic fields of the suspension system, guidance system, and propulsion system, as well as installation errors, train running vibration and other factors will affect the accuracy of the cross-induction loop speed measurement and positioning system. positioning accuracy.

With the country's steady advancement of rail transit technology innovation and the industrialization of key technology and equipment, the development goals of green, safe and intelligent railway equipment have become increasingly clear. Vigorously developing maglev train-related technologies will be one of the important development directions in the future. The National Key Research and Development Program Advanced Rail Transit Project has successively funded medium and high-speed maglev train projects with a speed of 200 km/h and 400 km/h, and a new generation of high-speed maglev train projects with a speed of 600 km/h has also been launched. These have higher precision and intelligent control requirements for the existing train suspension, propulsion, guidance and other systems, which are both a severe challenge and a rare development opportunity for related technologies in this field. At the same time, the structure of the maglev train is complicated, the control is difficult, the degree of intelligence is high, and the amount of data is large. The existing train positioning and speed measurement technology is not competent for the high-speed maglev train.

Train positioning and speed measurement technology are also important foundations for the realization of maglev train operation control and traffic scheduling. Especially for maglev trains driven by long-stator synchronous linear motors, the excitation control of the armature winding is closely related to the positioning of the train. Without accurate positioning technology, there will be no reliable long-stator synchronous linear motor control.

On the other hand, the current energy-saving train operation and intelligent control technology requires well-functioning train overspeed protection (ATP), automatic train driving (ATO) and automatic train monitoring (ATS) systems. These systems all need accurate, efficient and reliable train positioning and speed measurement technology as the basis. Without accurate train positioning and speed measurement technology, no matter how advanced the optimization algorithm is, it will not be able to achieve the expected results.

To sum up, to give full play to the advantages of maglev technology, improve the competitiveness of maglev trains, and to further realize energy-saving operation and intelligent control of trains, accurate, efficient and reliable train positioning and speed measurement technologies are of great significance.

Contents of the invention

The technical problem to be solved by the present invention is to use the trackside beacon positioning method to locate and measure the speed of the maglev train, improve the accuracy of the train positioning and speed measurement, and realize the effective monitoring of the train running status.

In order to achieve the above technical goals, the present invention adopts the way of trackside beacon positioning, and provides a three-dimensional magnetic coded train positioning marking method with small size, high reliability and simple coding. The probe performs corresponding scanning, decoding, and monitoring, which is simpler in structure, lower in cost, high in precision, and easy to install and maintain than the existing train positioning method.

In order to achieve the above-mentioned technical goals, the present invention specifically adopts the following technical solutions:

The three-dimensional magnetic code adopts a three-layer structure: including a base, an information coding layer and a protective layer; the upper part of the information coding layer includes a position detection area and an information identification area, and the position detection area is used for the calibration of the position of the magnetic code area, and the information The identification area is used to store information, and the lower part of the information coding layer adopts an n×j matrix sequence; the method includes the following steps:

(1) Data analysis: determine the type of encoded characters and the specifications of the three-dimensional magnetic code, and convert them into data characters according to the character set;

(2) Data encoding: convert the data characters into a bit stream, directly convert the decimal landmark data into a ternary data sequence, form a data codeword sequence for matrix encoding, and then the decoder recognizes and reads the three-dimensional magnetic code data codeword Sequentially acquire the data content of the three-dimensional magnetic code;

(3) Error correction coding: the data codeword sequence is partitioned and arranged, and the error correction codeword is added to the data codeword sequence to form a new sequence information, and additional sequence information is added at the end of the new sequence information;

(4) Construction matrix: put detection information, positioning information, additional information and code word module in the matrix sequence in the sequence that step (3) produces;

(5) Format and version information: put the format and version information in the sequence generated by step (3) into the information identification area to generate the final three-dimensional magnetic code;

(6) When the train passes the three-dimensional magnetic code, it reads the magnetic pole information of the three-dimensional magnetic code, and sends the read information to the on-board control unit, which decodes the information to obtain the real-time status information of the train.

Preferably, the three-dimensional magnetic code magnetic pole information reading method in step (6) is: when the train passes the three-dimensional magnetic code, the matrix sequence of the three-dimensional magnetic code is scanned by the on-board induction coil, and the on-board sensor detects the induction generated by the induction coil during the scanning process. Electromagnetic wave pulses, and transmit the detection information to the on-board control unit; the on-board control unit judges the polarity of the magnetic pole according to the direction of the pulse wave, performs a decoding operation, converts the decoded sequence into a binary computer language, and then calls the corresponding road sign from the established information database Finally, the train displacement is obtained through adjacent monitoring points, the train displacement is derived to obtain the running speed, and the running speed is derived to obtain the train acceleration.

Preferably, according to the matrix sequence, the landmark information is matrix-combined encoded by three symbols of permanent magnetic pole 'N', 'S' and non-magnetic '0' vacancy.

Preferably, the protective layer is made of non-magnetic material covering the surface of the information encoding layer.

Preferably, the position detection area is formed by nesting a larger square magnetic pole ring and a square magnet.

Preferably, the adhesive surface of the base is frosted.

Preferably, the base and the information coding layer are fixed by rivets or grooves, and the edges of the magnetic code are rounded.

Preferably, the protective layer is provided with an information marking place, which can identify the serial number and installation position information.

The present invention has following beneficial effects:

The invention realizes the precise positioning of the maglev train based on the trackside beacon mode, realizes the storage of the track position information through the different arrangements of the three code elements, and has the advantages of simple coding, fast reading, strong adaptability and the like. The train running speed can be obtained by deriving the displacement, and the train acceleration can be obtained by deriving the running speed. The precise monitoring of train position, speed and acceleration provides a basis for energy-saving operation and intelligent control of trains.

Description of drawings

Fig. 1 is a top view of the structure of the three-dimensional magnetic code maglev train positioning mark of the present invention.

Fig. 2 is a cross-sectional view of the encoding layer of the three-dimensional magnetic code maglev train positioning mark of the present invention.

Fig. 3 is a left view of the structure of the three-dimensional magnetic code maglev train positioning mark of the present invention.

In the figure: (1) the edge of the magnetic code, (2) and (9) indicate the magnetic code protection layer, (3) indicate the magnetic code information marking area, (4) indicate the information marking place, (5) indicate the base, (6) and (10) represent the position detection area, (7) the information identification area, (8) the information coding area (11) represent the permanent magnet symbol.

Detailed ways

The three-dimensional magnetic encoding method and its application technology in the field of positioning and speed measurement of maglev trains are a key technology related to the excitation of stator windings, traction force matching, and energy-saving operation of maglev trains. With the rapid development of the rail transit system in the direction of green, safe and intelligent, higher requirements are put forward for the train positioning technology, such as information collection speed and information accuracy. The present invention monitors state information such as the position, speed, and acceleration of the maglev train by adopting a three-dimensional magnetic encoding marking method based on the information calibration method, and provides basic basis for precise control of the maglev train.

The three-dimensional magnetic code marking method of the present invention adopts the 'N', 'S' polarity of the permanent magnet and the non-magnetic '0' vacancy in the information coding area to form the basic code element, and performs information coding and storage according to the preset matrix coding method.

The core part of the three-dimensional magnetic code lies in the information encoding method of its coding layer and the reading strategy of the three-dimensional magnetic code.

Three-dimensional magnetic code magnetic pole encoding process:

(1) Data analysis: Determine the type of encoded characters and the specifications of the three-dimensional magnetic code, and convert them into symbol characters according to the corresponding character set; under certain conditions of specifications, the higher the error correction level, the smaller the real data capacity.

(2) Data encoding: convert the data characters into a bit stream, directly convert the decimal landmark data into a ternary data sequence, and form a data codeword sequence for matrix encoding for efficient decoding, and then the decoder recognizes and reads The data content of the two-dimensional code can be obtained by the code word sequence of the three-dimensional magnetic code data.

(3) Error correction coding: Arrange the above code word sequence partitions according to the needs. In order to achieve a higher error tolerance rate of the magnetic code, an error correction code word needs to be added in the coding area, and the error correction code word is added to the data code word sequence Inside, it becomes a new sequence information, and additional suffix sequence information is added at the end of the sequence.

(4) Construct the final data information: under the condition that the specifications are determined, put the sequences generated above into the blocks in order.

(5) Constructing the matrix: put the detection information, positioning information, additional information and codeword modules into the corresponding matrix.

(6) Format and version information: Generate format and version information and put them into the corresponding information identification area to generate the final three-dimensional magnetic pole three-dimensional magnetic code.

The modern train itself has a full line condition information database, including the slope of the road section, the curve and the speed limit, etc. The function of the present invention is to provide the train with an accurate position (relative to the starting point) of the train operation, and the train control system can obtain the train operation information. The relevant information provides the basic technology for realizing the intelligent driving of future trains.

In order to illustrate the present invention more clearly, the following is based on the total length of the track route from Beijing South Railway Station to Shanghai Hongqiao Station about 1320 kilometers, and an information database with a decimal value range of [0-1320000] is established. The present invention adopts the magnetic pole 'S' , 'N' and '0' respectively represent the value '2', '1' and '0' are coded in ternary value

The encoding mode of the present invention can also adopt encoding modes such as letters, characters, Chinese characters, etc., and the basic method is consistent with the digital mode, so it will not be described too much here.

The indicator is set as: 0001 by means of digital encoding, and the data 1234 567 is encoded in the [0-1320000] information database as an example.

1. Data analysis: The Beijing-Shanghai rail transit line is usually 1320 kilometers long, and the train positioning and detection points are set according to the distance of one meter. A total of 1,320,001 identification information sequences are required for the entire line, and the ternary values are in the coding area size 15×10 matrix. It can meet the requirements. In addition, the three-dimensional magnetic code repeated sorting method is used to achieve a higher level of error correction to ensure the accuracy of the three-dimensional magnetic code.

2. Numerical conversion ternary: 1234 567 → 2022 2011 1120 1

Adding a 4-bit mode indicator (0001) before the above-mentioned real numerical sequence is convenient for storing the encoding mode and additional information, etc., and adding eight characters at the end of the numerical sequence to set it as a suffix information sequence (0000 0001).

3. Add symbol sequence: 0001 2022 2011 1120 1000 0000 1

In order to improve the error tolerance rate of the three-dimensional magnetic code and avoid decoding errors, an error correction sequence is added to the coding sequence, and the three-dimensional magnetic code elements are repeatedly arranged here to form a new sequence.

Error correction processing: form a set of 5×10 ternary sequences according to the above, and then perform error correction processing, that is, repeatedly encode 5×10 ternary sequences, add them to the coding sequence, and combine them into a final 15×10 coding sequence. Among them, a set of ternary sequences is represented as:

0000 0011 2200 2222 2200 1111 1111 2200 1100 0000 0000 0000 11

Supplement additional information bit: add information identification module and magnetic code position detection module to obtain it, as shown in figure (1).

Three-dimensional magnetic code magnetic pole information reading process:

Information sequence acquisition: The train code reader reads the three-dimensional magnetic code data code word sequence to obtain the road sign information sequence.

Adopt vertical (vertical ground) induction coils with a one-to-one correspondence relationship with the three-dimensional magnetic code magnetic code. When the train passes the three-dimensional magnetic code, the vertical induction coils are scanned sequentially in a single row of matrix columns. During the scanning process, the induction coils generate induction electromagnetic waveforms. The sensor detects the electromagnetic pulse of the induction coil and transmits it to the control system to read and store the information sequence of the magnetic code (the electromagnetic wave generated by the magnetic pole 'S' can be set as a forward pulse, and the electromagnetic pulse generated by the magnetic pole 'N' is a reverse pulse, and there is no electromagnetic wave In addition, the position detection area uses a nested rectangular ring to generate a pulse signal that is obviously different from the code area, which is convenient for the decoder to identify the three-dimensional magnetic code and avoid interference and misreading by external magnetic objects Because the area of the information identification area is small, the size of the magnetic code is relatively small, so that the storage capacity of the encoding method and format information of the encoding area is satisfied.

Three-dimensional magnetic code reading: the control system restores the three-dimensional magnetic code matrix sequence to the information sequence.

The above-mentioned strategy control system judges the magnetic pole polarity record according to the direction of the pulse wave and completes the control sequence set by the system in turn, performs the decoding operation according to the decoding method set by the system, and then converts it into binary computer language, and the system directly reads from the established information database It is enough to call the corresponding road condition information, and then provide accurate position information for the train control system. In addition, the train running displacement can be obtained through adjacent monitoring points, and then the running speed can be obtained by deriving the train displacement, and the running speed can be derived. Get the train acceleration. Then achieve the goal of accurate monitoring of train position, speed and acceleration, and provide a technical basis for train energy-saving operation and intelligent control.

Note: The specific reading method listed here is just a more specific and detailed description of the present invention, and does not have a specific reading method.

According to the drawings, the present invention includes three parts: a base, an information coding layer 8, and a magnetic code protection layer 2/9. Among them, the magnetic code protection layer 2/9 directly covers the information coding layer 8 to form a whole, and the magnetic code of the information coding layer 8 is protected to prevent it from falling off, being damaged or demagnetized; at the information coding layer 8, the road sign information is passed through the permanent magnet The magnetic poles 'N', 'S' and the non-magnetic '0' vacancy are encoded and stored in a preset magnetic code sequence composed of magnetic codes. The position detection area 6/9 is used to calibrate the position of the magnetic code area, which is convenient for decoding the scanning information of the vehicle probe and ensures accurate reading. The information identification area 7 is used to store information such as the format, version, and zero point of the three-dimensional magnetic code.

The three-dimensional magnetic code sets the position detection area 6/10 and the information identification area 7 in the information coding area, which are formed by nesting square magnetic pole rings and square magnets respectively, and the magnetic pieces different from the code element size of the coding area follow a preset specific matrix sequence arranged in format. The position detection area 6/10 is used to identify and read the magnetic code area, determine the scanning position of the decoder, improve the anti-interference ability, and ensure the accurate reading of the decoder; the information identification area 7 is used to store the format, version, and zero position of the three-dimensional magnetic code Click and wait for information.

The above-mentioned appearance selection base 5 and the information coding layer 8 are fixed by rivets or grooves, and the edge 1 of the magnetic code can be rounded.

The magnetic code protection layer 2/9 of the patent is provided with an information marking place 4, which can identify information such as serial numbers and installation positions, and is convenient for engineering installation and maintenance.

The three-dimensional magnetic encoding contains the encoding information and fault-tolerant information of the location. This position is an absolute position, no mutual influence, no cumulative error.

The code element of the magnetic code layer includes three kinds of magnetic pole 'N', magnetic pole 'S' and non-magnetic vacancy. The magnetic poles are realized by axially magnetized circular magnetic sheets (the circular magnetic sheets can be made of cylindrical magnet slices, and the thickness and excitation can be adjusted according to actual requirements).

The magnetic code element using rare earth permanent magnet materials has the advantages of strong magnetism, high positioning accuracy, high readability, and is not easy to demagnetize, and the size of the three-dimensional magnetic code is small.

The surface of the three-dimensional magnetic code is covered with non-magnetic material to prevent the magnetic code from falling off and being damaged, and it can prevent the magnetic properties of the magnetic code from deteriorating due to oxidation, corrosion, impact, etc., and improve the service life.

The three-dimensional magnetic code can be used normally in various harsh environments such as dusty, poor light, low temperature, rain and snow, and has a certain protective function.

The base design of the logo is frosted to ensure that the three-dimensional magnetic code is firmly pasted and improves reliability.

The three-dimensional magnetic code is provided with an information mark on the surface of the protective layer, which can mark the serial number, installation position and other information, which is convenient for engineering installation and maintenance.

As mentioned above, the present invention adopts the trackside beacon positioning method to locate and measure the speed of the maglev train, and sticks and pastes it in an orderly manner along the track of the maglev train according to the preset detection positions according to the set distance (the specific distance is determined according to the actual situation). fixed.

According to the above description, install the on-board probe at the corresponding position of the maglev train for corresponding scanning, decoding and monitoring. Every time the train scans a three-dimensional magnetic code, it can read the pre-stored information, and then obtain the train running position information. The train running speed is obtained by deriving the displacement, and the train acceleration is obtained by deriving the running speed. Accurate monitoring of train position, speed, and acceleration provides a basis for energy-saving operation and intelligent control of trains.

Claims (8)

1. A train location identification method based on a three-dimensional magnetic code, said three-dimensional magnetic code adopts a three-layer structure: comprising a base, an information coding layer and a protective layer; it is characterized in that, The upper part of the information encoding layer includes a position detection area and an information identification area, the position detection area is used for calibration of the position of the magnetic code area, the information identification area is used for storing information, and the lower part of the information encoding layer adopts an n×j matrix sequence; The method comprises the steps of: (1) Data analysis: determine the type of encoded characters and the specifications of the three-dimensional magnetic code, and convert them into data characters according to the character set; (2) Data encoding: convert the data characters into a bit stream, directly convert the decimal landmark data into a ternary data sequence, form a data codeword sequence for matrix encoding, and then the decoder recognizes and reads the three-dimensional magnetic code data codeword Sequentially acquire the data content of the three-dimensional magnetic code; (3) Error correction coding: the data codeword sequence is partitioned and arranged, and the error correction codeword is added to the data codeword sequence to form a new sequence information, and additional sequence information is added at the end of the new sequence information; (4) Construction matrix: put detection information, positioning information, additional information and code word module in the matrix sequence in the sequence that step (3) produces; (5) Format and version information: put the format and version information in the sequence generated by step (3) into the information identification area to generate the final three-dimensional magnetic code; (6) When the train passes the three-dimensional magnetic code, it reads the magnetic pole information of the three-dimensional magnetic code, and sends the read information to the on-board control unit, which decodes the information to obtain the real-time status information of the train. 2. A kind of train location marking method based on three-dimensional magnetic code as claimed in claim 1, is characterized in that, in the step (6), the three-dimensional magnetic code magnetic pole information reading method is: When the train passes the three-dimensional magnetic code, the matrix sequence of the three-dimensional magnetic code is scanned by the on-board induction coil, and the on-board sensor detects the induced electromagnetic wave pulse generated by the induction coil during the scanning process, and transmits the detection information to the on-board control unit; The on-board control unit judges the polarity of the magnetic pole according to the direction of the pulse wave, performs a decoding operation, converts the decoded sequence into a binary computer language, then calls the corresponding road sign information from the established information database, and finally obtains the train displacement through the adjacent monitoring point. The running speed is obtained by deriving the train displacement, and the train acceleration is obtained by deriving the running speed. 3. A kind of train location mark method based on three-dimensional magnetic code as claimed in claim 3, it is characterized in that, according to said matrix sequence, road sign information is passed through permanent magnet magnetic pole 'N', 'S' and non-magnetic '0' The three kinds of code elements of the empty positions are combined in matrix and encoded. 4. A method for identifying train location based on a three-dimensional magnetic code as claimed in claim 1, wherein the protective layer is made of a non-magnetic material covering the surface of the information coding layer. 5 . A method for identifying a train location based on a three-dimensional magnetic code as claimed in claim 1 , wherein the position detection area is formed by nesting a larger square magnetic pole ring and a square magnet. 6 . 6. A method for locating and marking a train based on a three-dimensional magnetic code as claimed in claim 1, wherein the adhesive surface of the base is frosted. 7. A method for locating a train based on a three-dimensional magnetic code as claimed in claim 1, wherein the base and the information coding layer are fixed by rivets or grooves, and the edges of the magnetic code are rounded. 8. A method for locating and marking a train based on a three-dimensional magnetic code as claimed in claim 1, wherein the protective layer is provided with an information marking place, which can identify the serial number and installation position information.