KR20170077615A - Speed measuring apparatus and speed measuring method for magnetci levitation train - Google Patents

Speed measuring apparatus and speed measuring method for magnetci levitation train Download PDF

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Publication number
KR20170077615A
KR20170077615A KR1020150187681A KR20150187681A KR20170077615A KR 20170077615 A KR20170077615 A KR 20170077615A KR 1020150187681 A KR1020150187681 A KR 1020150187681A KR 20150187681 A KR20150187681 A KR 20150187681A KR 20170077615 A KR20170077615 A KR 20170077615A
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South Korea
Prior art keywords
speed
laser
magnetic levitation
levitation train
laser beam
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KR1020150187681A
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Korean (ko)
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KR101779983B1 (en
Inventor
임재원
하창완
김창현
이종민
한형석
김봉섭
김동성
박도영
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한국기계연구원
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
    • G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
    • G01S17/50—Systems of measurement based on relative movement of target
    • G01S17/58—Velocity or trajectory determination systems; Sense-of-movement determination systems
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L13/00—Electric propulsion for monorail vehicles, suspension vehicles or rack railways; Magnetic suspension or levitation for vehicles
    • B60L13/04—Magnetic suspension or levitation for vehicles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L13/00—Electric propulsion for monorail vehicles, suspension vehicles or rack railways; Magnetic suspension or levitation for vehicles
    • B60L13/04—Magnetic suspension or levitation for vehicles
    • B60L13/06—Means to sense or control vehicle position or attitude with respect to railway
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
    • G01S7/4804—Auxiliary means for detecting or identifying lidar signals or the like, e.g. laser illuminators
    • G01S7/4806—Road traffic laser detectors
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
    • G01S7/481—Constructional features, e.g. arrangements of optical elements

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Remote Sensing (AREA)
  • General Physics & Mathematics (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Optics & Photonics (AREA)
  • Power Engineering (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Control Of Vehicles With Linear Motors And Vehicles That Are Magnetically Levitated (AREA)
  • Train Traffic Observation, Control, And Security (AREA)

Abstract

The present invention provides a speed measuring apparatus and a speed measuring method of a magnetic levitation train capable of precisely measuring the speed of a magnetic levitation train without providing a pattern on the ground.
An apparatus for measuring the speed of a magnetic levitation train according to an embodiment of the present invention includes a laser sensor for irradiating a laser toward the ground, A feature point extracting unit for extracting feature points formed according to the ground structure by analyzing the received signals, a feature point comparing unit for comparing positions of feature points formed by the same structure in signals received at different time zones, And a speed calculating section for calculating the speed of the magnetic levitation train according to the position of the minutiae point.

Description

[0001] SPEED MEASURING APPARATUS AND SPEED MEASURING METHOD FOR MAGNETIC LEVITATION TRAIN [0002]

The present invention relates to a speed measuring device and a speed measuring method, and more particularly, to a speed measuring device and a speed measuring method of a magnetic levitation train.

Generally, to measure the speed of a train, use an encoder connected to the wheels of a train or a speed meter with a Doppler sensor. However, the Doppler sensor has a problem that it is difficult to accurately measure the velocity in the rain, and the encoder has a problem that it is difficult to apply to a maglev train having no wheels.

On the other hand, conventionally, in order to measure the speed of the magnetic levitation train, a method of installing a reflection pattern on the ground and recognizing the velocity by attaching a sensor recognizing the reflection pattern to the vehicle has been utilized. However, this method has a problem in that it is difficult to measure the accurate pattern when the pattern is hidden due to the snow or foreign matter because the cost is increased because the pattern is installed on the ground.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetic levitation train velocity measuring device and a velocity measuring method capable of precisely measuring the velocity of a magnetic levitation train without providing a pattern on the ground, Method.

An apparatus for measuring the speed of a magnetic levitation train according to an embodiment of the present invention includes a laser sensor for irradiating a laser toward the ground, A feature point extracting unit for extracting feature points formed according to the ground structure by analyzing the received signals, a feature point comparing unit for comparing positions of feature points formed by the same structure in signals received at different time zones, And a speed calculating section for calculating the speed of the magnetic levitation train according to the position of the minutiae point.

Here, the laser sensor irradiates a laser beam of a line shape having a length, and the length may be 20 cm to 150 cm.

In addition, the laser sensor irradiates a laser beam toward a sleeper installed on a track, and the minutiae point extractor can extract minutiae formed by the sleeper.

Further, the laser sensor may irradiate a laser beam at a predetermined cycle.

The speed calculator may calculate the speed of the magnetic levitation train by dividing the interval between the minutiae points by the period of the measured signal.

According to another aspect of the present invention, there is provided a method for measuring the velocity of a magnetic levitation train, the method comprising: a laser irradiation step of irradiating a laser beam toward the ground; A laser receiving step of receiving a laser beam, a feature point extracting step of extracting feature points formed according to a ground structure by analyzing a received signal, a feature point comparing positions of feature points formed by the same structure in signals measured at different time points A comparing step, and a speed calculating step of calculating the speed of the magnetic levitation train according to the position of the minutiae point.

Here, the laser irradiation step irradiates a line-shaped laser having a length, and the length may be 30 cm to 150 cm.

In addition, in the laser irradiation step, the laser is irradiated toward the sleepers installed in the trajectory, and the minutiae formed by the sleepers in the minutiae extraction step can be extracted.

In the velocity calculating step, the velocity of the magnetic levitation train may be calculated by dividing the distance between the minutiae points by the time difference of the measured signal.

According to the embodiment of the present invention, the feature points are extracted using the laser sensor, and the speeds are calculated by comparing the positions of the feature points formed by the same structure. Therefore, even if the reflection pattern is not provided on the track, Can be measured.

FIG. 1 is a block diagram illustrating an apparatus for measuring the velocity of a magnetic levitation train according to an embodiment of the present invention.
FIG. 2 is a graph illustrating signals measured by a velocity measuring apparatus of a magnetic levitation train according to an embodiment of the present invention.
3 is a flowchart illustrating a method of measuring the velocity of a magnetic levitation train according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

FIG. 1 is a block diagram illustrating an apparatus for measuring the velocity of a magnetic levitation train according to an embodiment of the present invention.

1, the speed measuring apparatus 30 according to the present embodiment includes a laser sensor 31, a receiving unit 32, a feature point extracting unit 33, a feature point comparing unit 34, and a speed calculating unit 35). The magnetic levitation train 10 is caused to float on the orbit 20 provided with the sleepers 21 by magnetic force.

The length of the laser beam 36 irradiated by the laser sensor 31 may be 20 cm to 150 cm. The laser sensor 31 is a sensor for irradiating a laser beam in the form of a line having a length. The laser sensor 31 can irradiate the laser beam 36 such that the length of the laser beam 36 is long in the longitudinal direction of the orbit 20. [ The laser sensor 31 is installed to face the trajectory 20 at the lower surface of the maglev train 10 and can irradiate the laser beam 36 toward the sleepers 21 provided on the trajectory 20. [ Also, the laser sensor 31 may irradiate the laser beam 36 at a predetermined cycle, wherein the period may be 0.005 second to 0.2 second, and may be 0.01 second.

The receiving unit 32 may be configured to receive the laser beam reflected from the ground, and to receive the entire length of the reflected laser beam. The receiving section 32 can receive the periodically irradiated laser beam. In addition, the laser sensor 31 continuously irradiates the laser beam, and the receiver 32 can receive and store the reflected signal at a predetermined period.

FIG. 2 is a graph illustrating signals measured by a velocity measuring apparatus of a magnetic levitation train according to an embodiment of the present invention.

1 and 2, the minutiae point extractor 33 extracts the minutiae SP from the received signal, and the minutiae point refers to a portion reflected by the structure protruding from the orbit. As shown in FIG. 2, when the laser beam is reflected by the sleeper 21 mounted on the track 20, the characteristic point SP appears in the signal reflected according to the shape of the sleeper 21, And extracts a characteristic point SP represented by the sleeper 21 from the received signal. The present invention is not limited to this, and the characteristic point SP may be formed by another track structure other than the sleepers 21 have.

The feature point comparator 34 compares the feature points SP formed by the same structure in the received signals with a time difference to extract the interval between the signals. When the laser beam is irradiated at the first time T1 and the laser beam is irradiated at the second time T2 at 0.01 second intervals, the interval SD of the characteristic points SP is increased by 0.01 second as the magnetic levitation train 10 moves. Lt; / RTI > The feature point comparing unit 34 compares the feature points SP and measures the interval SD according to the position of the feature point SP.

The speed calculating section 35 calculates the speed of the magnetic levitation train 10 according to the position of the minutiae SP. The speed of the magnetic levitation train 10 can be calculated by dividing the interval SD between the feature points SP by the period of the received signal. For example, if the interval SD between the feature points SP is 120 cm and the period of the received signal is 0.01 second, the velocity of the maglev train 10 can be measured at 432 Km / h.

As described above, according to the present embodiment, the velocity of the maglev train 10 can be accurately measured by measuring the velocity of the maglev train 10 using the line-shaped laser sensor 31, The speed of the magnetic levitation train 10 can be measured in a non-contact manner without providing a reflection pattern on the magnetic levitation train 10.

Hereinafter, a method of measuring the velocity of a magnetic levitation train according to an embodiment of the present invention will be described. 3 is a flowchart illustrating a method of measuring the velocity of a magnetic levitation train according to an embodiment of the present invention.

1 to 3, the method for measuring the velocity of a magnetic levitation train according to the present embodiment includes laser irradiation step S101, laser reception step S102, feature point extraction step S103, feature point comparison step S104 And a speed calculating step S105.

In the laser irradiation step (S101), the laser beam (36) is irradiated toward the ground by the laser sensor (31), and the laser beam (36) in the form of a line having a length is irradiated. The length of the laser beam 36 irradiated by the laser sensor 31 may be 20 cm to 150 cm. The length of the laser beam 36 can be irradiated so as to be long in the longitudinal direction of the orbit 20. [ The laser sensor 31 is installed to face the trajectory 20 at the lower surface of the maglev train 10 and can irradiate the laser beam 36 toward the sleepers 21 provided on the trajectory 20. [ Also, the laser beam 36 may be irradiated at a predetermined cycle, wherein the period may be 0.005 second to 0.2 second, and may be 0.01 second.

In the laser receiving step (S102), the laser beam reflected on the ground is received, and the entire length of the reflected laser beam can be received. In the laser receiving step (S102), the periodically irradiated laser beam can be received, and the continuously irradiated laser beam can be received and stored at a predetermined period.

In the feature point extraction step (S103), the received signal is analyzed to extract feature points formed according to the ground structure. Here, the feature point SP means a portion reflected by the structure protruding from the trajectory 20. When the laser beam is reflected by the sleepers 21 mounted on the track 20, the characteristic points SP appear in the signal reflected according to the shape of the sleepers 21. In the characteristic point extraction step S103, ) Are extracted from the feature points SP.

In the feature point comparison step S104, the feature points SP formed by the same structure are compared with each other in the signals received with a time difference to extract the interval between the signals. When the laser beam is irradiated at the first time T1 and the laser beam is irradiated at the second time T2 at 0.01 second intervals, the interval SD of the characteristic points SP is increased by 0.01 second as the magnetic levitation train 10 moves. Lt; / RTI > The feature point comparing unit 34 compares the feature points SP and measures the interval SD according to the position of the feature point SP.

The speed calculating step S105 calculates the speed of the magnetic levitation train 10 according to the position of the minutiae SP. The speed of the magnetic levitation train 10 can be calculated by dividing the interval SD between the feature points SP by the period of the received signal. For example, if the interval SD between the feature points SP is 120 cm and the period of the received signal is 0.01 second, the velocity of the maglev train 10 can be measured at 432 Km / h.

As described above, according to the present embodiment, the laser beam is irradiated in a line shape and the signals reflected by the sleepers are analyzed to extract the characteristic points, thereby measuring the velocity of the magnetic levitation train 10, The speed of the magnetic levitation train 10 can be measured in a non-contact manner without providing a reflection pattern on the magnetic levitation train 10.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but many variations and modifications may be made without departing from the spirit and scope of the invention. And it goes without saying that they belong to the scope of the present invention.

10: Maglev train 20: Orbit
21: sleepers 30: speed measuring device
31: laser sensor 32:
33: feature point extracting unit 35: speed calculating unit
36: laser beam

Claims (9)

An apparatus for measuring the speed of a magnetic levitation train that measures the velocity of a magnetic levitation train,
A laser sensor for irradiating the laser toward the ground;
A receiver for receiving the reflected laser beam from the ground;
A feature point extracting unit for analyzing a received signal and extracting feature points formed according to a ground structure;
A feature point comparing unit for comparing positions of feature points formed by the same structure in signals received at different time zones; And
And a speed calculating section for calculating the speed of the magnetic levitation train according to the position of the minutiae point. The method according to claim 1,
Wherein the laser sensor irradiates a laser beam in the form of a line having a length and the length is 20 cm to 150 cm. The method according to claim 1,
Wherein the laser sensor irradiates a laser beam toward a sleeper installed on a track, and the minutiae point extractor extracts minutiae formed by the sleeper. The method according to claim 1,
Wherein the laser sensor irradiates the laser beam at a predetermined cycle. 5. The method of claim 4,
Wherein the speed calculating unit calculates the speed of the magnetic levitation train by dividing the interval between the characteristic points by the cycle of the measured signal. A method for measuring the speed of a magnetic levitation train that measures the velocity of a magnetic levitation train,
A laser irradiation step of irradiating a laser beam toward the ground;
A laser receiving step of receiving the laser beam reflected on the ground;
A feature point extracting step of extracting feature points formed according to a ground structure by analyzing a received signal;
A feature point comparing step of comparing positions of feature points formed by the same structure in signals measured at different time zones; And
And a speed calculating step of calculating a speed of the magnetic levitation train according to the position of the minutiae point. The method according to claim 6,
Wherein the laser irradiating step irradiates a line-shaped laser having a length, and the length is from 30 cm to 150 cm. 8. The method of claim 7,
Wherein the laser is irradiated to the sleeper installed in the trajectory in the laser irradiation step and the characteristic points formed by the sleeper are extracted in the characteristic point extraction step. 8. The method of claim 7,
Wherein the velocity of the magnetic levitation train in the velocity calculating step is calculated by dividing the distance between the feature points by the time difference of the measured signal.
KR1020150187681A 2015-12-28 2015-12-28 Speed measuring apparatus and speed measuring method for magnetci levitation train KR101779983B1 (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
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CN108045263A (en) * 2017-12-08 2018-05-18 江西理工大学 Magnetic suspension train is accurately positioned and velocity-measuring system and method
CN111717668A (en) * 2020-05-28 2020-09-29 湖南凌翔磁浮科技有限责任公司 Position detection system and method and magnetic suspension conveying device
KR20210071315A (en) * 2019-12-06 2021-06-16 한국철도기술연구원 High-Speed Relative Position Measurement Method Using Multiple Light Source Scanning and Detecting Capable, of Transmitting Specific Position Mark
CN113428189A (en) * 2021-07-14 2021-09-24 中北大学 Magnetic suspension train speed measurement positioning method based on induced voltage phase reversal
CN115266160A (en) * 2022-08-18 2022-11-01 中国人民解放军国防科技大学 Performance detection method and device for induction loop positioning and speed measuring system

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JP4329240B2 (en) * 2000-07-24 2009-09-09 三菱電機株式会社 Vehicle position detection device and vehicle speed detection device
JP2015165754A (en) * 2014-03-03 2015-09-17 株式会社京三製作所 Train speed detecting device, and train speed detecting method
JP6145417B2 (en) * 2014-03-03 2017-06-14 株式会社京三製作所 Train position detection apparatus and train position detection method

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108045263A (en) * 2017-12-08 2018-05-18 江西理工大学 Magnetic suspension train is accurately positioned and velocity-measuring system and method
CN108045263B (en) * 2017-12-08 2020-09-01 江西理工大学 Precise positioning and speed measuring system and method for magnetic suspension train
KR20210071315A (en) * 2019-12-06 2021-06-16 한국철도기술연구원 High-Speed Relative Position Measurement Method Using Multiple Light Source Scanning and Detecting Capable, of Transmitting Specific Position Mark
CN111717668A (en) * 2020-05-28 2020-09-29 湖南凌翔磁浮科技有限责任公司 Position detection system and method and magnetic suspension conveying device
CN113428189A (en) * 2021-07-14 2021-09-24 中北大学 Magnetic suspension train speed measurement positioning method based on induced voltage phase reversal
CN113428189B (en) * 2021-07-14 2022-09-06 中北大学 Magnetic suspension train speed measurement positioning method based on induced voltage phase reversal
CN115266160A (en) * 2022-08-18 2022-11-01 中国人民解放军国防科技大学 Performance detection method and device for induction loop positioning and speed measuring system

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