JP2000142406A - Ground element detecting device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect only a ground element for measurement from various installations provided to a railway line. SOLUTION: This ground element detecting device includes a ground element 11 provided on the ground and reflecting a light beam 1a from a projector 1, a photodetector 6 provided at a bottom of a rolling stock traveling on a railway line and receiving reflected light from the ground element 11, and a judging circuit detecting the ground element 11 from an output of the photodetector 6. In such a case, high reflection parts 11a, 11b, 11c having high reflectivity of the light beam 1a and a low reflection part 11d having a low reflectivity of the light beam 1a are alternately provided side by side on the ground element 11 along a traveling direction of the rolling stock.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the measurement of the position of a ground carrier for railway maintenance.

[0002]

2. Description of the Related Art Conventionally, for the purpose of maintenance of a railway, grounding elements for measurement have been provided at various points on a railway line, and the positions of the grounding elements have been measured. In the position measurement of the ground child, a person moves while walking between the ground children using a dedicated measurement gauge, and is manually measured one by one. But,
In the measurement by walking, much time is required for movement, and the amount of work is limited. Therefore, in order to automate this measurement, it is conceivable to run a maintenance vehicle on the track and automatically measure the position of the ground child from the maintenance vehicle.

[0003]

However, as viewed from the maintenance vehicle, at the position where the ground child is located, there may also be installed objects other than the ground child, such as level crossings and turnouts. Only ground children needed to be detected.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to provide a ground child detecting apparatus and method capable of detecting only ground children from various installations.

[0005]

According to a first aspect of the present invention, there is provided a ground member provided on the ground for reflecting a light beam from a floodlight, and a ground member provided at a lower portion of a vehicle running on a railroad track. A receiver for receiving the reflected light of, and a ground detector that has a determination circuit for detecting the ground from the output of the light receiver, on the ground, along the traveling direction of the vehicle, A high-reflection part with high light reflectance,
A ground detector according to the present invention, wherein low-reflecting portions having low reflectance are provided alternately.

[0006] According to a second aspect of the present invention, the light emitting device includes:
A light beam provided in the lower part of the vehicle and narrowed down in a spot shape emits light intermittently according to pulse output means for outputting a pulse of a predetermined frequency, and the determination circuit calculates a logical product of the pulse and the output of the light receiver. The ground child detecting device according to claim 1, wherein the ground child is detected from the result.

According to a third aspect of the present invention, the irradiation area of the light beam emitted from the light projector is smaller than the high reflection portion and the low reflection portion provided on the ground element. It is a ground detector.

According to a fourth aspect of the present invention, a light beam from the projector is reflected by a ground member provided on the ground, and the reflected light reflected by the ground member is received by a lower portion of a vehicle running on a railroad track, In the ground detection method of detecting the ground child from the received reflected light, a high reflection part having a high reflectance of the light beam is provided on the ground child along a traveling direction of the vehicle; A ground element detection method, wherein reflection units are provided alternately.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the configuration of a ground detector according to a first embodiment of the present invention. The light emitter 1 and the light receiver 2 are fixed to a lower part of a maintenance vehicle running on rails. The light projector 1 emits a light emitting laser 1a. The light emitting laser 1a is reflected by a ground element 11 fixed on the ground and received by a light receiver 6. The light projector 1 is mounted on the front side of the light receiver 6 in the traveling direction of the vehicle.

The ground rail 11 is provided between the right rail 12a and the left rail 12b on the ground. In addition, the ground member 11 has an upper surface 11a of the ground member 11 lower than the rail surface 12 which is the upper surface of the rail and higher than the paving stone surface 13 which is the upper surface of the paving stone laid under the rail. Installed in

The front end 11e and the rear end 11f of the ground child 11
Have step surfaces 11b and 1 lower than upper surface 11a.
1c is provided. Upper surface 11a and step surface 11
b and 11c are painted white. Furthermore, the upper surface 1
At the center of 1a, a black cross line 11d is drawn.
The vertical line of the crosshair 11d is drawn parallel to the traveling direction of the vehicle, and the horizontal line is drawn at right angles to the traveling direction. The thickness of the crosshair 11d is about 5 mm.

The light emitting laser 1a emitted from the light emitting device 1 is narrowed down in a spot shape, and its irradiation area is rectangular. The irradiation area of the light emitting laser 1a on the upper surface 11a of the ground element 11 is about 2 mm in the traveling direction of the vehicle and about 10 mm in the direction perpendicular to the traveling direction. The length of the irradiation area in the traveling direction of the vehicle is smaller than the thickness of the crosshair 11d. The irradiation area is horizontally long because the shape of the light emitting portion of the semiconductor laser incorporated in the projector 1 is horizontally long.

Since the light emitter 1 and the light receiver 6 are fixed to the lower part of the running vehicle, the irradiation area of the light emitting laser 1a emitted from the light emitter 1 moves as the vehicle travels. The light projector 1 and the light receiver 6 are fixed at positions where the trajectory of the irradiation area on the ground element 11 intersects the horizontal line of the crosshair 11d. The length of the trajectory from which the irradiation area moves from the front end 11e of the ground member 11 to the horizontal line of the crosshair 11d is 360 mm. Further, the optical axes of the light emitter 1 and the light receiver 6 are adjusted so that the light emitting laser 1a from the light emitter 1 and the light receiving field of the light receiver 6 intersect at the upper surface 11a of the ground element 11.

The light receiving field of the light receiver 6 has a divergent angle as shown in FIG. The condition that the spread angle of the light-receiving field should be satisfied is that the step surfaces 11b and 11c, which are the lowest positions of the ground element 11,
When the reflected light of the light emitting laser 1a at the upper surface 11a, which is the highest position, can be received and the ground element 11 is not in the light receiving field, the paving stone surface 13 reflects the light emitting laser 1a. Is not to receive the reflected light from the

The height at which the ground wire 11 is installed is such that the upper surface 11a of the ground wire 11 is 20 mm ± 3 mm from the rail surface 12.
It is a lowered position. Also, the step surface 11 of the ground child 11
The difference in height between b, 11c and the upper surface 11a is 22 mm. The pavement surface 13 has irregularities, but is 120 under the rail surface 12.
mm.

In addition to the above installation situation, taking into account the fact that the light emitter 1 and the light receiver 6 move up and down due to vibration while the vehicle is moving, and the case where the ground element 11 is tilted back and forth, left and right, The divergence angle has some allowance.

FIG. 3 is a block diagram showing the configuration of the electric circuit of the first embodiment. The light projector 1 includes a semiconductor laser that emits the light emitting laser 1a and an optical system that narrows the light emitting laser 1a into a spot. By using a semiconductor laser as the light source of the projector 1, the laser driving circuit can be simplified and the size of the optical system can be reduced.

Light emitting laser 1a emitted from light emitting device 1
Is reflected by the ground element 11 and reflected and scattered light 1b
Is received by the light receiver 6. The light receiver 6 incorporates a silicon-PIN photodiode as a light-receiving element, and the reflected and scattered light 1b received by the silicon-PIN photodiode is photoelectrically converted into an electric light-receiving pulse 6a to the amplifier circuit 7. Is output. Silicon-
A reverse bias voltage is applied to the PIN photodiode from the analog circuit power supply 10 to increase the response speed.

A logic circuit power supply 5 supplies power to the oscillation clock generation circuit 4 and the judgment circuit 9. The oscillation clock generation circuit 4 outputs the oscillation clock 4a to the laser oscillation circuit 2 and outputs the timing gate signal 4b to the determination circuit 9. The oscillation clock 4a and the timing gate signal 4b are synchronized pulse trains, and both have a frequency of 5 kHz. The laser high-voltage power supply 3 supplies a drive voltage for oscillation to the laser oscillation circuit 2. The laser oscillation circuit 2 oscillates a semiconductor laser incorporated in the projector 1 to emit light. The semiconductor laser emits light intermittently according to the oscillation clock 4a. That is, the frequency of light emission is 5 kHz.

The frequency at which the semiconductor laser emits light intermittently is 5
The reason why the frequency is set to kHz is that while the maintenance vehicle is being moved, the semiconductor laser of the projector 1 fixed to the lower part of the maintenance vehicle is intermittently lit, and the projection laser 1a is moved without any gaps.
This is for irradiating the light beam on the upper side of the light emitting element 1. Since the irradiation area of the light emitting laser 1a has a length of 2 mm in the traveling direction of the vehicle on the ground element 11, if the time interval of the irradiation is the same as the time the vehicle moves by 2 mm, the light emitting laser 1a can be placed on the ground without gaps. The child 11 can be irradiated. The maximum speed of the maintenance vehicle of this embodiment is 35 k / h
m (9.7 m / sec), the frequency was set to 5 kHz in order to set the irradiation interval to 2 mm at this maximum speed. By irradiating the ground beam 11 with the laser beam without any gap, the cross-beam 11d can be reliably irradiated with the projection laser 1a regardless of the timing at which the cross-hair 11d appears. Can be caught.

The light receiving pulse 6a output from the light receiver 6 is
The signal is amplified by the amplifier circuit 7 and input to the comparator 8. The analog circuit power supply 10 supplies power to the light receiver 6, the amplifier circuit 7, and the comparator 8. The comparator 8 receives the output of the amplifier circuit 7 and the reference voltage 9a output by the determination circuit 9.
Is also entered. The comparator 8 compares these inputs and outputs “1” when the output of the amplifier circuit 7 is higher than the reference voltage 9a, and outputs “0” when the output of the amplifier circuit 7 is lower than the reference voltage 9a. That is, the comparator 8 converts the output of the amplifier circuit 7 which is an analog signal into a comparator output 8a which is a digital signal. In the following description, the peak voltage of the output pulse of the amplifier circuit 7 is referred to as a light receiving voltage.

The reference voltage 9a is set so as to satisfy the following conditions. First, the reference voltage 9a is set higher than the noise voltage included in the output of the amplifier circuit 7.
This is to prevent the comparator output 8a from being erroneously output due to the noise voltage. Second, the reference voltage 9a is set to be higher than the light receiving voltage caused by the projection laser 1a irradiating the black cross line 11d on the upper surface 11a of the ground element 11 with the reflected scattered light 1b. Third, the white portion of the ground child 11, that is, the upper surface 1
1a, a portion other than the crosshair 11d, and a step surface 11b,
11c is set lower than the received light voltage. The second and third conditions are conditions for distinguishing the black cross line 11d of the ground child 11 from other white portions.

The output 8a of the comparator 8 is input to the judgment circuit 9. The judgment circuit 9 determines that the comparator output 8a is
It is determined whether or not the reflection is caused by the light from the ground beam 11.
When the irradiation area of “a” approaches the crosshair 11 d of the ground stylus 11, the start signal 9 b is output.

The determining circuit 9 is a logical product circuit for calculating the logical product of the timing gate signal 4b input to the determining circuit and the comparator output 8a, a counter for counting the pulses output by the logical product circuit, A timer that measures a period during which the AND circuit does not output a pulse.

FIG. 4 shows how the reflected light incident on the light receiver 6 changes when the maintenance vehicle passes over the ground element 11. The state A in the figure is a state before the light emitting laser 1a reaches the front end 11e of the ground element 11, and the light emitting laser 1a is applied to the cobblestone surface 13. At this time, the reflected scattered light 1b is reflected by the paving stone surface 13, but this reflected light is out of the light receiving field of the light receiver 6, so that it does not enter the light receiver 6. Therefore, in this state, the light receiving pulse 6a is not output from the light receiving device 6, and the output of the comparator 8 is fixed at "0".

When the maintenance vehicle moves in the traveling direction,
In the state B in which the projection laser 1a is irradiated between the front end 11e and the cross line 11d, the irradiation area on the step surface 11b or the upper surface 11a enters the light receiving field of the light receiver 6. In this state, the reflected light from the white part of the ground element 11 enters the light receiving field of view.
Output pulse exceeds the reference voltage 9a, and the comparator 8 outputs a "1" level pulse.

In the state C where the vehicle is further moved and the irradiation area of the light emitting laser 1a is located on the crosshair 11d of the ground member 11, the reflection level is reduced. Is below the reference voltage 9a. Therefore, at this position, the output of the comparator 8 is "0".

Further, when the vehicle moves a little, and the irradiation area reaches the range from immediately after the crosshair 11d to the rear end 11f, that is, the state D, the light receiving level becomes the same as the state B again, and the comparator 8 sets the "1" level. Output pulse. In the state E after the irradiation area has passed the rear end 11f of the ground element 11, similarly to the state A, the output of the light receiving pulse 6a from the light receiver 6 is lost, and the output of the comparator 8 becomes "0".

The change in the above state is shown in the timing chart of FIG. In synchronization with the oscillation clock 4a output from the oscillation clock generation circuit 4, the light projector 1
To emit light. The timing gate signal 4b output from the oscillation clock generation circuit 4 is also synchronized with these signals. The frequencies of the oscillation clock 4a, the projection laser 1a, and the timing gate signal 4b are all 5 kHz.

State A to state E in FIG. 5 correspond to state A to state E in FIG. In the state A, since the reflected scattered light 1b does not enter the light receiver 6, the light receiver 6 does not output the light receiving pulse 6a.

In the state B, the reflected light 1
When b is incident, the light receiver 6 generates a light receiving pulse 6a. The light receiving pulse 6 a is amplified by the amplifier circuit 7, converted into a digital pulse (comparator output 8 a) by the comparator 8, and input to the determination circuit 9. An AND circuit built in the decision circuit 9 receives the comparator output 8a and the timing gate signal 4b generated by the oscillation clock generation circuit 4, and calculates the logical product of these inputs. This is to confirm that the comparator output 8a has been input to the determination circuit 9 within a prescribed allowable time after the emission of the light emitting laser 1a. That is, the generated comparator output 8a is
Is confirmed by the reflected light of the projection laser 1a. At this time, if the comparator output 8a is due to extraneous light, the result of the AND operation with the timing gate signal 4b is "0". Will be eliminated within. The counter included in the determination circuit 9 counts the number N1 of pulses that pass through the AND circuit similarly included in the determination circuit 9.

In the state C, the irradiation area of the projection laser 1a approaches the crosshair 11d of the ground beam 11, so that the intensity of the reflected scattered light 1b decreases, and the output of the amplifier circuit 7 becomes higher than the reference voltage 9a. And the comparator output 8a disappears. A timer incorporated in the determination circuit 9 measures a period during which this pulse is not output, and converts this time into a pulse number N2.

The determination circuit 9 compares the above N1 and N2 with predetermined determination conditions, and if the conditions are satisfied, determines that the ground child 11 has been detected, and outputs a starting signal 9b. N
The determination conditions of 1, N2 are determined as follows. Since the length of the step surface 11b and the upper surface 11a of the ground member 11 in the vehicle traveling direction is constant, N1 is defined by the upper limit and the lower limit of the moving speed of the vehicle. In the present embodiment, the length in the traveling direction from the front end 11e of the ground member 11 to the crosshair 11d is 360 mm, the upper limit of the moving speed is 35 km / h, and the lower limit is 5 km / h. Accordingly, the range of N1 is 185 or more and 1188 or less, but the upper and lower limits have some margin, and the lower limit is 150 pulses and the upper limit is 1500 pulses. In addition, the number N2 of intermittent pulses due to the crosshair 11d is set to 3 or more and 18 or less because the width of the crosshair 11d in the traveling direction is 5 mm.

That is, when N1 is 150 or more and 1500 or less and N2 is 3 or more and 18 or less and the pulse of the comparator output 8a is input to the determination circuit 9 again, the determination circuit 9 An origin signal 9b is output. In the counting of N1, reflection may be hindered by the attachment of dust or the like on the ground element 11, so that one pulse is allowed to be skipped, the pulse is regarded as a continuous pulse, and the counting is continued.

At the position of the ground child 11 on the track, a railroad crossing and a turnout are installed in addition to the ground child 11. In the case of a railroad crossing, the number of continuous pulses corresponding to N1 exceeds 1500 pulses, because the length of the vehicle is longer in the traveling direction than the ground rail 11 and the speed of the vehicle is reduced when the vehicle passes through the railroad crossing. In the case of the branching device, since there is no portion corresponding to the crosshair 11d, the pulse in the comparator output 8a is not interrupted. Therefore, erroneous determination due to reflection from these installed objects can be eliminated under the above N1 and N2 conditions.

Next, a second embodiment of the present invention is shown in FIG. In the second embodiment, the positions of the light emitter 1 and the light receiver 6 are set to the first position.
This is the opposite of the embodiment. That is, the light receiver 6 is provided in front of the vehicle, and the light projector 1 is provided behind. In the present embodiment, the irradiation area of the light emitting laser 1a becomes a blind spot from the light receiver 6 due to the step between the step surface 11b and the upper surface 11a, and the pulse output is temporarily interrupted. The criterion of N1 is reduced by the amount.

[0037]

According to the present invention, while a maintenance vehicle is running on a railway track, only the grounding element for measurement can be detected from various installations installed between the left and right rails on the railway track. There is no possibility of measuring objects other than the child. Further, since the position of the crosshair, which is the center position of the ground child, can be detected, accurate measurement is possible. Further, if the light emitter is intermittently emitted and reflected light is taken in at a timing synchronized with this emission, malfunction due to extraneous light can be prevented. Further, if the irradiation area of the light beam emitted from the projector is made smaller than the high reflection portion and the low reflection portion provided on the ground child, malfunctions due to vibration of the maintenance vehicle, inclination of the ground child, and the like can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram of a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a positional relationship of an optical system according to the first embodiment.

FIG. 3 is a diagram illustrating a light receiving range of a light receiver according to the first embodiment.

FIG. 4 is a diagram for explaining the operation of the first embodiment.

FIG. 5 is a timing chart of the first embodiment.

FIG. 6 is a diagram showing a positional relationship of an optical system according to a second embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Floodlight 1a Floodlight laser (light beam) 1b Reflected scattered light (reflected light) 2 Laser oscillation circuit 3 High voltage power supply for laser 4 Oscillation clock generation circuit 4a Oscillation clock 5 Logic circuit power supply 6 Light receiver 6a Light reception pulse 7 Amplifier circuit 8 Comparator 8a Comparator output 9 Judgment circuit 9a Reference voltage 9b Origin signal 10 Analog circuit power supply 11 Ground element 11a Top surface (high reflection part) 11b, 11c Step surface (high reflection part) 11d Cross line (low reflection part) 11e Front end 11f Rear end 12 Rail surface 12a Right rail 12b Left rail 13 Paving stone surface

 ──────────────────────────────────────────────────続 き Continuing on the front page F term (reference) 2F065 AA01 AA19 BB28 CC40 DD00 DD12 DD14 FF31 FF44 GG06 GG08 GG12 HH04 HH12 JJ01 JJ09 JJ18 NN02 PP01 QQ00 QQ04 QQ25 QQ51 5H161 AA01 BB20 CC02 ADB0304 DA01 EA04

Claims (4)

[Claims] 1. A ground member provided on the ground for reflecting light rays from a projector, a light receiver provided at a lower portion of a vehicle running on a railway line and receiving light reflected from the ground member, And a determination circuit for detecting the ground child from the output of the ground child detecting device, a high reflection part having a high reflectance of the light beam on the ground child along a traveling direction of the vehicle; A low-reflection section having a low surface area is provided alternately. 2. The projector according to claim 1, wherein the light emitter is provided below the vehicle, and emits a light beam narrowed down in a spot shape intermittently in accordance with a pulse output unit that outputs a pulse having a predetermined frequency. 2. The ground detector according to claim 1, wherein a logical AND with an output of the light receiver is obtained, and the ground detector is detected from the result. 3. An irradiation area of a light beam emitted from the light projector,
The ground detecting element according to claim 2, wherein the ground detecting element is smaller than the high-reflecting portion and the low-reflecting portion provided on the grounding element. 4. A light beam from a projector is reflected by a ground member provided on the ground, and the reflected light reflected by the ground member is received by a lower part of a vehicle running on a railway line, and the ground light is received from the received reflected light. In the ground child detecting method of detecting a child, on the ground child, along the traveling direction of the vehicle, a high-reflection portion having a high reflectance of the light beam and a low-reflection portion having a low reflectance are alternately arranged. A method for detecting a ground child, wherein the method is provided.