JPS62159009A - Direction measuring instrument for moving body - Google Patents

Abstract

PURPOSE:To certainly measure the proceeding direction of a moving body without being interrupted by other moving bodies even in case a travel course of the moving body has plural lanes by providing plural light reflection means at a high position to look down upon the moving body. CONSTITUTION:The light reflection means 5-7 are provided on an orthogonally crossed line to the direction X in parallel to a road 1, for instance, via a pole 2 and a beam 4 above the road 1 having the plural lanes. On the other hand, a light emitting means 9 incorporating a photodetector therein is provided on the upper part of the moving body 8 traveling on the road 1 and the means 9 emits surface-shaped beams 10 to cross orthogonally to the proceeding direction Y of the moving body 8. When the beams 10 strike upon one of the means 5-7, the light reflection means reflects the light in the same direction as the incident direction of the light. Accordingly, the reflected light again returns to the means 9 and is made incident on the incorporated photodetector and converted into an electrical signal. In this way, an angle theta of deviation of the proceeding direction of the moving body with respect to the reference direction X can be operated based on the distance traveled by the moving body 8 while the photodetector detects the reflected light of the next reflected means after detecting the reflected light of one of the means 5-7 and the distance between the means 5 and 7.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an azimuth measuring device for a moving object, and in particular to a device for measuring the heading of a moving object with respect to a reference azimuth using reflection of light. Regarding equipment.

[Prior Art] For example, when guiding an aircraft from the runway to the taxiway at an airport, or when driving a car, an unmanned mobile guided vehicle in a factory, a golf cart, etc. on a predetermined course, it is necessary to If the direction of travel could be measured, it would be possible to automatically guide the vehicle based on it, which would be very convenient.

Therefore, the applicant of the present application has developed the Vitra, which measures the traveling direction of a moving object as described above, with special features 1 [? It was proposed in No. 6O-972L. The invention disclosed in this application will be briefly explained below. In the present invention, the first light reflecting means and the second light reflecting means are provided on the right side and the left side of the path along which the moving body should travel, respectively.

These first and second light reflecting means have an optical property of reflecting incident light in the same direction, and for example, a corner cube or the like is used. On the other hand, the movable body is provided with a light projecting means for projecting light in left and right directions in the traveling direction of the movable body, and first and second photodetectors in association with the light projecting means.

The first photodetector is for receiving light projected from the light projecting means and reflected by the first light reflecting means. The second photodetector is for receiving the light projected from the light projecting means and reflected by the second light reflecting means. Then, the distance traveled by the moving object between when one of the first and second photodetectors detects the reflected light and when the other detects the reflected light is measured, and this measurement result is combined with the first and second photodetectors. Distance between the second light reflecting means (this distance is known in advance)
Based on this, the deviation angle of the moving direction of the moving object with respect to a predetermined reference direction is calculated.

According to the above invention, since the traveling direction of a moving body is measured using the reflection of light, the structure is much smaller than, for example, the conventional method of measuring the traveling direction using radio waves.
! It is simple and the device is inexpensive, and it also complies with the Radio Law.
III and is not affected by radio noise. Furthermore, even if the road surface of the route on which the moving object is to travel is in poor condition, the light reflecting means can be easily installed, and the detection sensitivity of reflected light will not be reduced. Furthermore, there is little need for maintenance and inspection of the light reflecting means (time and expense can be significantly reduced).

[Problems to be Solved by the Invention] As described above, the invention proposed by the present applicant achieves various effects, but on the other hand, it also includes problems to be solved. That is, in the above invention, the number of roads on which the moving object is traveling is one
In the case of a lane, it is possible to accurately measure the traveling direction without any problems, but if the road has multiple lanes, the light beam emitted from the moving object is blocked by other moving objects running on the median line, and the light reflecting means In such cases, it is impossible to measure the heading.

This invention was made to solve the above-mentioned problems, and even if the course the moving object is traveling on has multiple lanes, the moving object can be reliably moved without being obstructed by other moving objects. It is an object of the present invention to provide a direction measuring device for a moving body that can measure the direction of movement.

[Means for Solving the Problems] A direction measuring device for a moving object according to the present invention provides at least a first 2 light reflecting means are provided. These first and second light reflecting means are
It has the optical property of reflecting incident light in the same direction.

On the other hand, the moving body includes a surface light beam emitting means for emitting a planar light beam perpendicular to the direction of movement of the moving body upward, and a surface light beam emitting means for emitting a planar light beam perpendicular to the direction of movement of the moving body, and a light beam emitted from the surface light beam emitting means and reflected by the light reflecting means. A photodetector for detecting the distance traveled by the moving body between when the photodetector detects the reflected light from the first light reflecting means and when the photodetector detects the reflected light from the second light reflecting means. A travel distance measuring means for measuring, a setting means for presetting and storing the distance between the first and second light reflecting means, and a calculation means for calculating a deviation angle of the moving direction of the moving body with respect to a reference direction. and is provided.

[Function] In the present invention, the calculation means calculates the deviation of the moving direction of the moving object from the reference direction based on the distance measured by the distance measuring means and the distance information set and stored in the setting means. By calculating the angle, the moving direction of the moving body can be determined. Furthermore, since the light reflecting means is provided above the moving object, even if there is another moving object running alongside, the light beam is not blocked by the other moving object, making it possible to measure the traveling direction.

[Example] FIG. 1 is an external perspective view showing an embodiment of the present invention.

In the figure, balls 2 and 3 are erected at predetermined positions on the left and right sides of a road 1 having multiple lanes. A beam 4 is stepped between the balls 2 and 3. This beam 4
includes a first light reflecting means 5, a second light reflecting means 7,
A third light reflecting means 6 is provided. These light reflecting means have an optical property of reflecting the incident light in the same direction as the incident direction, and for example, a corner cube or the like is used. Here, the height of the beam 4 is selected to be sufficiently higher than the height of the moving body 8 passing under it. Further, the light reflecting means 5 to 7 are arranged on a line perpendicular to the reference direction X shown in FIG. Note that this reference direction X may be selected, for example, parallel to the road 1, or may be selected, for example, north, south, east, west, etc., regardless of the direction in which the road extends. Further, the third light reflecting means 6 is provided between the first light reflecting means 5 and the second light reflecting means 7, but its arrangement position is between the first light reflecting means 5 and the second light reflecting means 7. It is selected so that it is shifted in either the left or right direction from the center position with respect to the means 7 (near the center line of the road 1 in FIG. 2).

On the other hand, a light emitting means 9 is provided on the upper part of the moving body 8 traveling on the road 1. This light emitting means 9 emits a planar light beam (hereinafter referred to as a planar beam) 10 orthogonal to the traveling direction Y of the moving body 8 . The spread angle of this plane beam 10 is selected such that when the moving body 8 passes under the beam 4, a part of the plane beam always hits the first to third light reflecting means 5 to 7.

In the above configuration, this embodiment measures the deviation angle θ (see FIG. 2) of the moving direction Y of the moving object 9 with respect to the reference direction X.

FIG. 3 is a sectional view showing details of the light emitting means 9 shown in FIG. 1. In the figure, eleven cylinders 92 are housed inside a housing 91. Inside this lens barrel 92, a semiconductor laser 9 is provided.
3, a beam splitter 94, and a lens 95 are housed. Also, a quarter wavelength plate 96 is provided at the light exit of the lens barrel 92.
is provided.

Furthermore, a light receiver 97 is attached to a portion of the inner side surface of the housing 91 that faces the beam splitter 94 .

In the above-described configuration, the straight light emitted from the semiconductor laser 93 passes through the beam splitter 94 and passes through the light lens 9.
5. This lens 95 spreads the linear light and converts it into a plane beam 10. This plane beam 10 is a quarter-wave plate 9
6 and then emitted to the outside. By the way, when the plane beam 10 hits any of the light reflecting means 5 to 7, the light reflecting means reflects the light in the same direction as the direction of incidence of the light.

Therefore, the reflected light returns to the light emitting means 9 again.

Therefore, this reflected light is returned to straight light by the simulated lens 95 that passes through the quarter-wave plate 96, and enters the beam splitter 94. At this point, the light incident on the beam splitter 94 passes through the quarter-wave plate 96 twice, so its wavelength is shifted by a half wavelength with respect to the light emitted from the semiconductor laser 93.

Therefore, the beam splitter 94
Reflects the reflected light from the object without transmitting it. The reflected light from the beam splitter 94 passes through a hole provided on the side of the lens barrel 92 and enters the light receiver 97 . The light receiver 97 converts the incident light into an electrical signal.

FIG. 4 is a schematic block diagram showing one embodiment of the present invention. In the figure, the output of the light receiver 97 is the pulse selection circuit 1
1 to flip-flop 12. Among the three light reception pulses obtained from the light receiver 97, the pulse selection circuit 11 selects a light reception pulse based on the light reflected from the first light reflection means 5 and a light reception pulse based on the reflection light from the second light reflection means 7. The pulse is selectively passed. The set output (Q) of flip-flop 12 is AND gate 1
3 is applied to one input of AND gate 14, and its polarity is inverted and applied to one input of AND gate 14. The output of the pulse generator 15 is applied to the other input of the AND gate 13. This pulse generator 15 generates pulses corresponding to the traveling distance of the moving body 8. The output of AND gate 13 is given to counter 16. The count value of this counter 16 is given to the other input of the AND gate 14. In addition, the reset output of the flip-flop 12 (
Φ) is given to the timer 18. The output of this timer 18 is given to the counter 16 as a reset output. The output j of the AND gate 14 is applied to one input of the division circuit 17. The output of the interval setting section 19 is applied to the other input of the division circuit 17. The number of pulses corresponding to the distance between the first light reflecting means 5 and the second light reflecting means 7 is set in advance in the interval setting section 19. Division circuit 17
The output of is given to the polarity addition circuit 21 via the conversion circuit 20. On the other hand, the output of the light receiver 97 is given to the positive/negative discrimination circuit 22. This positive/negative determining circuit 22 is for determining whether the deviation angle θ obtained by the conversion circuit 20 is positive or negative. The output of the positive/negative discrimination circuit 22 is sent to the polarity addition circuit 21
given to. The polarity adding circuit 21 adds positive or negative polarity to the output of the converting circuit 20 in response to the output of the positive/negative determining circuit 22 . The output of the polarity adding circuit 21 is given to various utilization circuits (not shown) as azimuth information of the moving body 8.

FIG. 5 is a block diagram showing details of the pulse selection circuit 11 shown in FIG. 4. In the figure, the pulse selection circuit 11 is composed of a ring counter 23 and an OR gate 24. The output of the light receiver 97 is given to the ring counter 23 . When the first light reception pulse is applied to this ring counter 23, only the first bit becomes logic "1".
When the second light reception pulse is given, only the second bit becomes logic "1", and when the third light reception pulse is given, only the third bit becomes logic "1". The logic outputs of the first bit and the third bit are applied to flip-flop 12 via OR gate 24, respectively. Further, the logic output of the third bit is given to the ring counter 23 as a reset signal. In such a configuration, the pulse selection circuit 11 cancels the second light reception pulse and passes the first light reception pulse and the third light reception pulse. Furthermore, when the third light reception pulse is output, the ring counter 23 is reset (all O's).

FIG. 6 shows details of the positive/negative discrimination circuit 22 shown in FIG. 4.
099 diagram. In the figure, this positive/negative discrimination circuit 22 includes a ring counter 25 and a first and second timer circuit 2.
6 and 27, and a comparison circuit 28.

The ring counter 25 is the ring counter 23 shown in FIG.
The configuration is similar to that, and the light reception pulse of the light receiver 97 is input.

Further, the logic output of the first bit of the ring counter 25 is applied to one input of the first timer circuit 26.

Further, the logic output of the second bit is sent to the first clock circuit 26.
and the - input of the second clock circuit 27. Further, the logic output of the third bit is applied to the other input of the second clock circuit 27, and is also applied to the ring counter 25 as a reset signal. The first timer circuit 26 measures the time width between the two logical outputs provided from the ring counter 25 . The same applies to the second clock circuit 27. The output of the first clock circuit 26 is output from the comparator circuit 28.
is given to one input. The output of the second clock circuit 27 is applied to the other input of the comparison circuit 28.

Comparison circuit 28 includes first and second timer circuits 26 and 2.
7 is larger and outputs a positive or negative polarity signal based on the comparison result. This polarity signal is given to the polarity addition circuit 21.

FIG. 7 is a timing chart showing the light pulses received from the light receiver 97. FIG. 8 is a geometric layout diagram for explaining the measurement principle of an embodiment of the present invention. The operation of the above embodiment will be described below with reference to FIGS. 7 and 8.

Now, as shown in FIG. 2, it is assumed that the traveling direction Y of the moving body 8 is deviated from the reference direction X by θ. In this case, the surface beam 10 from the light emitting means 9 first impinges on the first light reflecting means 5. Since the first light reflecting means 5 reflects the incident light in the same direction as the incident direction, the reflected light returns to the light emitting means 9 and is deflected by the light lens 95 that passes through the quarter wavelength plate 96 and becomes a beam. The light enters the splitter 94. Since this incident light is shifted by a half wavelength from the output light of the semiconductor laser 93, the beam splitter 94 reflects the incident light and makes it enter the light receiver 97.

In response, the light receiver 97 derives the first light reception pulse and supplies the light reception pulse to the pulse selection circuit 11 and the positive/negative discrimination circuit 22.

Since the pulse selection circuit 11 passes the first light-receiving pulse as in the previous example 3a, the light-receiving pulse is applied to the flip-flop 12. Since this flip-flop 12 derives a set output from the first input and a reset output from the next input, the pulse selection circuit 11
It is set at the first received light pulse that passes through. The set output (high level) of the flip 70 knob 12 is given to the AND gate 13, which is activated and at the same time is inverted to low level and output to the AND gate 14.
is given to disable this AND gate 14.

Accordingly, the pulses generated from the pulse generator 15 are given to the counter 16 via the AND gate 13.
Counter 16 counts the number of pulses applied. Here, the pulse generator 15 generates a pulse every time the movable body 8 advances a predetermined unit distance, and for example, a rotary encoder or the like that detects the rotation of the wheels of the movable body 8 is used. Therefore, by counting the number of output pulses from the pulse generator 15, the traveling distance of the moving body 8 can be measured.

When the moving body 8 travels a little and the surface beam 10 hits the third light reflecting means 6, the second light reception pulse is output from the light receiver 97. Since the pulse selection circuit 11 does not allow this second received light pulse to pass, the flip-flop 12 is not inverted and the counter 16 continues counting pulses.

Roughly speaking, when the moving body 8 travels and the plane beam 10 hits the second light reflecting means 7, the third light reception pulse is output from the light receiver 97. This third received light pulse passes through the pulse selection circuit 11 and resets the flip-flop 12. Therefore, the flip 70 knob 12 has its set output at a low level and its reset output at a high level. Accordingly, AND Gate 13 is disabled,
And the AND gate 14 is activated. Therefore, the counter 16 measures the distance traveled by the movable body 8 between when the light receiver 97 detects the reflected light from the first light reflecting means 5 and when it detects the reflected light from the second light reflecting means 7. The number n of correlated pulses is counted, and the counted value n is applied to one input of the division circuit 17 via the AND gate 14. Further, the reset output of the flip-flop 12 is given as a reset signal to the counter 16 after a certain time delay determined by the timer 18.

The other input of the division circuit 17 is given the setting value nw of the interval setting section 19. This interval setting section 19 includes a first
The distance Ill between the light reflecting means 5 and the second light reflecting means 7
A value nw correlated to dQ is set in advance. That is,
The number of pulses that would be obtained from the pulse generator 15 if the moving object 8 traveled the distance di is preset in the interval setting section 19. Therefore, the division circuit 17
is calculated by dividing the count III n of the counter 16 by a set value nw that correlates to the mounting interval of the first and second light reflecting means 5 and 7 (n/nw) Lt, sin θ'. As shown in FIG. 84, this angle θ' is the angle that the plane beam 10 makes with respect to the line segment d connecting the light reflecting means 5 and 7. is equal to the angle θ formed by Therefore, the division circuit 17 calculates sin θ. The output of the division circuit 17 is given to a conversion circuit 20, and sin θ is converted into an angle θ. This conversion circuit 20
Although not shown, for example, sin θ (0≦θ
<90") each antilog (sine value) set R
The division li1 (n /n
w) is configured to read out an angle θ corresponding to an antilogous number equal to w).

The angle θ derived from the conversion circuit 20 is an absolute value,
It is not clear whether the polarity is positive or negative with respect to the reference direction X. Therefore, a positive/negative determining circuit 22 is provided for the purpose of determining whether the angle θ is positive or negative.

Next, the operation of this positive/negative discrimination circuit 22 will be explained.

As shown in FIG. 2, when the moving body 8 is tilted to the right with respect to the reference direction X, the light receiving pulse as shown in FIG. 7 is obtained from the light receiver 97. That is, the interval ta between the first and second received light pulses is longer than the interval tb between the 21st and third received pulses. This is based on the fact that the third light reflecting means 6 is provided shifted to the right of the center position, as shown in FIG. First clock circuit 26
detects the time interval ta between the first received light pulse and the second received light pulse. On the other hand, the second timer circuit 27 measures the time interval tb between the second light reception pulse and the third light reception pulse.
Detect. The comparison circuit 28 compares which of the first and second timer circuits 26 and 27 has a larger output.

In this case, since the output of the first clock circuit 26 is larger, the comparison circuit 28 outputs, for example, a positive polarity signal and supplies it to the polarity adding circuit 21. Accordingly, the polarity addition circuit 21 adds a positive polarity to the absolute value angle θ output from the conversion circuit 20.

On the other hand, considering the case where the traveling direction Y of the moving object 8 is shifted to the left with respect to the reference direction The second timer circuit 27 detects the time interval between the received light pulse based on the reflected light of the third light reflecting means 6 and the received light pulse based on the reflected light of the third light reflecting means 6. The time interval between the received light pulse and the received light pulse based on the reflected light of No. 5 is detected. Therefore, in this case, the second clock circuit 2
7 is larger than the output of the first clock circuit 26 , the comparator circuit 28 derives a negative polarity signal and supplies it to the polarity adding circuit 21 . Accordingly, the polarity addition circuit 21 adds a negative polarity to the absolute value angle θ from the conversion circuit 20.

The azimuth information obtained by the embodiments described above can be displayed, for example, on a display to call the driver's attention, or it can be input into a device that automatically corrects the deviation angle. It can also be used for automatic guidance.

In addition, in the above embodiment, for convenience of explanation, only one set of the first to third light reflecting means is provided, but when this invention is used for automatic guidance etc., when the moving body 8 passes A plurality of sets of similar light reflecting means may be provided at appropriate locations on the path.

In addition, this invention is applicable not only to automobiles but also to golf carts at golf courses, aircraft moving on taxiways at airports,
Various transportation vehicles within the premises, guidance wagons for automatically guiding blind people, automatic vacuum cleaners, various agricultural equipment, and M! Of course, it can also be applied to wiring equipment. That is,
It can be applied to all moving objects that move on a plane.

Further, in the above embodiment, the third light reflecting means 6 is provided in order to determine whether the deviation angle is positive or negative, but this third light reflecting means 6 is not an essential component of the present invention. It may be omitted if there is no need to determine.

Furthermore, in the above embodiment, in order to detect the travel distance of the moving body 8, the pulse generator 15 that emits pulses according to the rotation of the wheels is used, but other methods can be used to detect the traveling distance of the moving body 8.
It is also possible to detect the distance traveled. For example, the moving body 8 is provided with an ultrasonic oscillator, an electromagnetic wave generator, or an infrared ray generator that projects ultrasonic waves, electromagnetic waves, or light onto a moving plane, and the reflected waves are detected, and the distance traveled by the moving body 8 is determined by the Doppler effect or the like. may be calculated and measured.

Roughly speaking, in the above embodiment, the semiconductor laser 93 is used as a light source.
However, it is of course possible to use other light sources. However, it is preferable to use a light source with sharp directivity.

[Effects of the Invention] As described above, according to the present invention, the light reflecting means is provided at a high position overlooking the moving object, so even if there is another moving object running alongside, the light is not reflected. This allows the light to reliably hit each light reflecting means without being blocked, making it possible to measure the direction. Therefore, the present invention is particularly effective when a moving object travels on a course having multiple lanes.

In addition, the moving direction of a moving body can be accurately measured with a simple and inexpensive configuration, and there is almost no need for maintenance or inspection, making it possible to significantly save time and costs.

[Brief explanation of drawings]

FIG. 1 is an external perspective view showing an embodiment of the present invention. FIG. 2 is a diagram showing the relationship between the installation state of the light reflecting means and the running state of the moving body. FIG. 3 is a sectional view showing details of the light reflecting means. FIG. 4 is a schematic block diagram showing one embodiment of the present invention. FIG. 5 is a block diagram showing details of the pulse selection circuit. FIG. 6 is a block diagram showing details of the positive/negative discrimination circuit. FIG. 7 is a timing chart showing pulses received by the light receiver. FIG. 8 is a geometric layout diagram for explaining the principle of the subchamber in one embodiment of the present invention. In the figure, 1 is a road, 5 is a first light reflecting means, 6 is a third light reflecting means, 7 is a second light reflecting means, 8 is a moving body,
9 is a light emitting means, 93 is a semiconductor laser, 94 is a beam splitter, 95 is a lens, 96 is a quarter wavelength plate, 97 is a light receiver, 11 is a pulse selection circuit, 15 is a pulse generator,
16 is a counter, 17 is a vAtx circuit, 19 is an interval setting section, 20 is a conversion circuit, 21 is a polarity addition circuit, and 22 is a positive/negative discrimination circuit.

Claims (3)

[Claims] (1) A device for detecting a deviation in the traveling direction of a moving body from a reference direction by using reflection of light, the device including: and at least first and second light reflecting means are provided so as to look down on the moving body, the light reflecting means has a characteristic of reflecting incident light in the same direction as the incident direction, and the moving body A surface light beam emitting means for emitting a planar light beam perpendicular to the traveling direction thereof upward; and a light detection device for detecting light emitted from the surface light beam emitting means and reflected by the light reflecting means. a distance traveled by the moving body between when the photodetector detects the reflected light from the first light reflecting means and when the photodetector detects the reflected light from the second light reflecting means; a distance measuring means for measuring the distance; a setting means for presetting and storing a distance between the first and second light reflecting means; a distance measured by the distance measuring means;
and a calculation means for calculating a deviation angle of the traveling direction of the mobile object with respect to the reference direction based on the distance information set and stored in the setting means. (2) The distance measuring means operates according to the movement of the moving object, and includes a pulse generating means that generates a pulse every time the moving object moves a predetermined unit distance; Counting of the pulses is started in response to detecting whichever of the reflected lights of the first and second light reflecting means is incident earlier, and in response to detecting whichever of the reflected lights is incident later. and a pulse counting means for terminating counting, wherein the setting means sets and stores the number of pulses corresponding to the distance between the first and second light reflecting means. A direction measuring device for a moving object as described above. (3) A third light reflecting means is provided between the first and second light reflecting means at a position shifted from the center thereof, and the timing of receiving the reflected light of the first light reflecting means and the third light reflecting means are controlled. the time width between the timing of receiving the reflected light of the third light reflecting means and the timing of receiving the reflected light of the second light reflecting means; The azimuth measuring device for a moving body according to claim 1 or 2, further comprising a sign/minor determining unit for determining whether the deviation angle calculated by the calculating unit is positive or negative based on the magnitude with respect to the width.