JPS61253417A - Position-measuring apparatus for moving object - Google Patents

Abstract

PURPOSE:To enable the detection of position with a simple and inexpensive construction and without requiring inspection and maintenance as well, by measuring the current position of a moving body utilizing the reflection of light beam. CONSTITUTION:Light beams 5R and 5L are turned to scan light reflecting means 2R and 2L with a bearing measuring scanner 4 and the ongoing bearing Y of a moving body 3 with respect to a predetermined reference bearing X. Then, light beam 8 is turned to scan light reflecting means 2R and 2L with a position measuring scanner 7 to detect the reflected light thereof. The angle data detected is stored into a register. Then, a computing circuit calculates the current bearing of the moving body 3 on the basis of the angle data stored into the register and the ongoing bearing Y measured with a bearing measuring scanner 4. This almost eliminates the need for maintaining and inspecting the light reflecting means, thereby enabling a drastic reduction in the time and labor.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a position measuring device for a moving body, and more particularly to a device for measuring the current position of a moving body using reflection of light.

[Prior Art] Conventionally, as a device for measuring the current position of a moving object such as a car or an unmanned mobile guided vehicle in a factory, radio wave transmission sources are installed at multiple locations on the ground, and the radio waves are transmitted on the moving object. There was a device that received radio waves and calculated the current position of a moving object based on the receiving direction.

[Problem 1 to be Solved by the Invention The position measuring device using radio waves as described above has a problem in that it is expensive because it requires a plurality of transmitting devices. There is also the problem that frequent inspections and maintenance must be performed in order for the transmitting device to operate normally at all times. In particular, when used outside the mold, the environment in which the transmitting device is installed becomes harsh, which increases the frequency of inspection and maintenance. Furthermore, since the above-described position measuring device uses radio waves, there are also problems in that it is subject to regulations under the Radio Law and is affected by radio wave noise.

Therefore, an object of the present invention is to provide a position detection device for a moving object that has a simple and inexpensive configuration, requires little inspection or maintenance, and is not subject to any regulations under the Radio Law.

Means for Solving Problem E] The present invention provides first and second light reflecting means at predetermined coordinate positions on the right and left sides of a route along which a moving body should move, and the first and second light reflecting means are provided at predetermined coordinate positions on the right and left sides of the route along which a moving body should travel, and these light reflecting means are provided from the moving body to The current position of a moving body is measured by rotating and scanning a light beam toward a light reflecting means and detecting the reflected light. , an angle detection means, a data acquisition means, and a calculation means. The first and second light reflecting means have an optical property of reflecting incident light in the same direction as the incident direction. The azimuth measuring means is for measuring the traveling azimuth of the moving object with respect to a predetermined reference azimuth. The rotational scanning means is for rotating and scanning the light beam from the moving body. The photodetector is for detecting light emitted from the rotating scanning means and reflected by the first or second light reflecting means. The angle detection means is for detecting the rotation angle of the rotation scanning means. The data acquisition means is for acquiring angle data from the angle detection means in response to the detection output of the photodetector. The calculation means is for calculating the current position of the moving object based on the traveling direction measured by the direction measurement means and the angle data taken in by the data acquisition means.

[Operation] In this invention, since the coordinate positions of the first and second light reflecting means are known in advance, the moving direction of the moving body with respect to the reference direction is measured, and the current position of the moving body and the first and second light reflecting means are measured. By measuring the angular relationship with the second light reflecting means, the calculating means can calculate the current position of the moving body from the geometrical relationship based on the measured results.

[Embodiment] FIG. 1 is an illustrative diagram showing an outline of an embodiment of the present invention. In the figure, light reflecting means 2R and 2L are provided on the right and left sides of the road 1, respectively. These light reflecting means 2R and 2L 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. Further, the light reflecting means 2R and 2L are selected such that a line segment d connecting each of them is orthogonal to a predetermined reference direction X. This reference direction X may be selected to be parallel to the road 1, for example, or may be selected to correspond to north, south, east, west, etc., regardless of the direction in which the road extends.

On the other hand, a moving body 3 such as a car is provided with a direction measuring scanner 4 for measuring its traveling direction Y and a position measuring scanner 7 for measuring its current position. The orientation measuring scanner 4 emits light beams 5R and 5L in the right and left directions orthogonal to the traveling direction Y of the moving body 3. The position measuring scanner 7 is for rotating and scanning the light beam 8 around the moving object.

FIG. 2 is a diagram showing the internal structure of the orientation measuring scanner 4 shown in FIG. 1, and shows the orientation measuring scanner 4 viewed from the front. In the figure, the orientation measuring scanner 4 includes a pair of left and right light emitting/receiving units 4L and 4R. The light emitting/receiving unit 4L is for emitting light to the left side of the moving body 3, and the light emitting/receiving unit 4R is for emitting light to the left side of the moving body 3.
This is to emit light to the right side of the Note that since these light emitting and receiving units 4L and 4R have the same structure and are bilaterally symmetrical, the right light emitting and receiving unit 4R will be described here as a representative. Inside the lens barrel 41R is a light source 42R.
, a lens 43R, and a half mirror 44R are housed. As the light source 42R, a light source that emits a laser beam or the like with sharp directivity is used. The lens 43R is for converting the light emitted from the light source 42R into a planar light beam 5R that spreads in the vertical direction. The reason why such a planar beam is used is that even if the moving body 3 vibrates a little, the light beam 5
This is to ensure that the light R hits the light reflecting means 2R. The light beam 5R exiting the lens 43R is a half mirror 4
The light passes through 4R and is emitted to the outside. Further, the half mirror 44R reflects the reflected light 6R from the light reflecting means 2R. A light receiver 45R is provided at a position where it can detect the reflected light of the half mirror 44R. This light receiver 45R uses, for example, a photodiode or a phototransistor, and derives a detection signal in response to receiving reflected light from the half mirror 44R.

FIG. 3 is a diagram showing the internal structure of the position measuring scanner 7 shown in FIG. 1, and shows the W18Il regular scanner 7 viewed from the front. In the figure, a lens barrel 71 is housed and held inside a housing 70. A light source 72, a lens 73, and a half mirror 74 are housed inside this lens barrel 71. As the light source 70, a light source that emits a sharply directional light such as a laser beam is used.

The lens 73 is for expanding the light emitted from the light 1II72 in the vertical direction to form a planar light beam 8.

Such a planar light beam 8 is used for the moving object 3.
This is to ensure that the light beam 8 hits the light reflecting means 2R and 2L even if the light beam 8 vibrates to some extent. The light beam 8 exiting the lens 73 passes through a half mirror 74 and is emitted to the outside. Further, the half mirror 74 is connected to the light reflecting means 2.
It receives and reflects the reflected light from R and 2L. A light receiver 75 is provided at a position where the reflected light from the half mirror 74 can be detected. This light receiver 75 uses, for example, a photodiode, a phototransistor, etc., and a half mirror.
In response to receiving the reflected light from 74, a detection signal is derived. Further, the housing 70 is connected to an encoder 76 and a motor 77. The motor 77 is connected to the housing 7
By rotating the light beam 8, the light beam 8 is rotated and scanned around the moving body 3. The encoder 76 is for detecting the rotation angle of the light beam 8, and its reference angle is selected to match the traveling direction Y of the moving body 3.

FIG. 4 is a schematic block diagram showing the direction measuring device mounted on the moving body 3. As shown in FIG. 5 and 6 are illustrative views for explaining the operation of the direction measuring device shown in FIG. 4. FIG. below,
The configuration and operation of the direction measuring device shown in FIG. 4 will be explained with reference to FIGS. 5 and 6.

Now, as shown in FIG. 6, it is assumed that the moving direction Y of the moving body 3 is at an angle of θ with respect to the reference direction X. In this case, as shown in FIG. 5, the light beam 5L from the left light projecting/receiving unit 4L first hits the light reflecting means 2L. Since the light reflecting means 2L reflects the received light beam 5L in the same direction as the incident direction, the reflected light returns to the half mirror 44L,
It is reflected by this half mirror 44L and is reflected to the receiver 45.
incident on L. In response, the light receiver 45L derives a detection output and provides the detection output to the first-arrival discrimination circuit 10 and also to the flip-flop 12 via the OR gate 11. Since this flip-flop 12 derives a set output from the first input and a reset output from the next input, the light receiver 4 that first detects the reflected light
Set at 5L output. The set output (high level) of the flip-flop 12 is applied to the AND gate 13, activating the AND gate 13, and is inverted to low level and applied to the AND gate 14.
Disable D gate 14.

Accordingly, the pulses generated from the pulse generator 15 are AN
Since it is given to the counter 16 via the D gate 13,
Counter 16 counts the number of pulses applied. Here, the pulse generator 15 generates a pulse every time the movable body 3 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 3 is used. Therefore, by counting the number of output pulses from the pulse generator 15, the travel distance of the moving object 3 can be measured.

When the moving body 3 travels a little and comes to the position shown by the dotted line in FIG. 5, the light beam 5.R from the light projecting/receiving unit 4R hits the light reflecting means 2R. Therefore, the reflected light from the light reflecting means 2R returns to the half mirror 44R, and this half mirror 44R
The light is reflected by the light beam and enters the light receiver 45R. depending on,
The light receiver 45R derives a detection output and supplies the detection output to the first-come-first-served discrimination circuit 10 and also to the flip 70 knob 12 via the OR gate 11. flip 70 tube 1
2, since the output of the light receiver 45R is the second signal, its output logic state is inverted, and a low level signal is derived from the set output terminal, and a high level signal is derived from the reset output terminal. Accordingly, AND gate 13 is disabled and AND gate 14 is enabled. Therefore, the counter 16 counts the number of pulses n that correlates with the distance history traveled by the mobile object 3 from the time when the light receiver 45m detects the reflected light until the time when the light receiver 45R detects the reflected light,
The division circuit 17 divides the counted value n through the AND gate 14.
is given to one input. 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. A value n that correlates to the distance dl between the light reflecting means 2R and 2L is set in advance in this interval setting section 19. That is, the number of pulses that would be obtained from the pulse generator 15 if the moving object 3 traveled the distance dfL is preset in the interval setting section 19.

Therefore, the division port 2s17 is the count value n of the counter 16.
is the setting value nw that correlates to the installation interval of the light reflectors 2R and 2L.
Divide by (n/nw) to find sinθ'. This angle θ' is as shown in FIG.
It is the angle that the light beams 5L and 5R make with respect to the line segment d connecting
is equal to the angle θ formed by Therefore, the division circuit 17 has s
Calculate inθ. The output of the division circuit 17 is sent to the conversion circuit 20
is given, and sin θ is converted into angle θ. Although not shown, this conversion circuit 20 has, for example, sin θ at each address.
It includes a ROM in which each antilog number (sine value) of (0≦θ<90@) is set, and the division value (n/
The angle θ is configured to read out an angle θ corresponding to an antilogous number equal to nw). The angle θ derived from the conversion circuit 20 is
It is an absolute value, and the angle θ is either positive or negative with respect to the reference direction
It is not clear whether Therefore, for the purpose of determining whether the angle θ is positive or negative, the output of the conversion circuit 2° is
1 is given.

The first arrival determination circuit 10 determines which of the detection outputs of the light receiver 45R and the light receiver 45L came first, and provides the first arrival determination output to the positive/negative determination circuit 21. The positive/negative determining circuit 21 determines whether the angle θ is positive or negative based on the output of the first arrival determining circuit 10. That is, the positive/negative discrimination circuit 21 detects that the detection output of the light receiver 45R has preceded the first-arrival discrimination circuit 1.
0, the angle θ is determined to be negative (-), and when the first-arrival determining circuit 10 determines that the detection output of the light receiver 45m has preceded, the angle θ is determined to be positive (+).

For example, when the moving object 3 travels as shown in FIG. 5, the light receiver 45L derives the detection output first, so the first-come-first-served discrimination circuit 21 discriminates the angle θ as positive (+) and outputs 10. do.

As described above, according to the azimuth measuring device shown in FIG. 4, it is possible to accurately measure the angle θ that the traveling azimuth Y of the moving object 3 makes with respect to the reference azimuth X.

FIG. 7 is a schematic block diagram showing a position measuring device mounted on the moving body 3. As shown in FIG. In the figure, the differentiating circuit 22 has a third
The output of the photoreceiver 75 shown in the figure is given. The output of this differentiating circuit 22 is given to a T-type flip 70 tube 23.

This T-type flip 7O tube 23 is configured such that its output is inverted every time a differential pulse is input from the differentiator circuit 22. The Q output of T-type flip 70 tube 23 is AND
The signal is applied to one input of the gate 24 and is inverted and applied to one input of the AND gate 25. These A
The output of the waveform shaping circuit 26 is applied to the other input of the ND gates 24 and 25.

This waveform shaping circuit 26 is connected to an encoder 76 as shown in FIG.
This is a circuit for shaping the waveform of the output into a pulse signal.

The outputs of AND gates 24 and 25 are provided to registers 27 and 28, respectively.

The outputs of registers 27 and 28 are given to arithmetic circuit 29. Further, the arithmetic circuit 29 is given azimuth information from the positive/negative discrimination circuit 21 shown in FIG. Arithmetic circuit 2
Reference numeral 9 is for calculating the current position of the moving body based on the given data or information, and its output is given to the utilization device 30. The device 30 to be used may include, for example, an autopilot device, a display device, and the like.

8 and 9 are diagrams for measuring the operation of the measuring device shown in FIG. 7. In particular, FIG. shows geometrically the positional relationship between the moving body 3 and the light reflecting means 2R and 2L. The operation of the position measuring device shown in FIG. 7 will be described below with reference to FIGS. 8 and 9. It is now assumed that the traveling direction of the moving body 3 has already been measured by the direction measuring scanner 4 and the direction measuring device shown in FIG.

In this state, the position measuring scanner 7 is rotated by the motor 77, and therefore the light beam 8 is rotated and scanned. This light beam 8 is, for example, a light reflecting means 2L.
If it hits the light beam, the light reflecting means 2L reflects the light in the same direction as the incident direction of the light beam, so the reflected light returns to the half mirror 74 of the position measuring scanner 7, is reflected by this half mirror 74, and is received. The light enters the vessel 75.

Therefore, the light receiver 75 derives a detection output.

The detection output of this light receiver 75 is differentiated by a differentiating circuit 22, and is applied to the T-type flip 70 tube 23 as a differentiated pulse. Assuming that the Q output of the T-type flip 70 tube 23 was initially at O- level, the Q output is inverted to high level due to the input of the differential pulse. therefore,
AND gate 24 is opened and AND gate 25 is closed.

Therefore, the angle data φ is output from the encoder 76 and is waveform-shaped by the waveform shaping circuit 26.

is stored in register 27 through AND gate 24. Next, when the position measuring scanner 7 is rotated and displaced to the position indicated by the dotted line in FIG. 8, the light beam 8 hits the light reflecting means 2R.

Note that since the rotation speed of the position measuring scanner 7 by the motor 77 is quite fast, the moving body 3 is
Assume that there is almost no movement. Light reflecting means 2R
reflect the incident light beam 8 in the same direction. Therefore, the half mirror 74 receives and reflects the reflected light from the light reflecting means 2R. The reflected light from the half mirror 74 is sent to the receiver 75.
The light is received by and a detection output is derived. Therefore,
A differential pulse is output from the differentiating circuit 22, and the output state of the T-type flip-flop 23 is inverted. That is, Q
Output becomes low level. In this state, AND gate 24 is closed and AND gate 25 is opened. Therefore, the angle data φ from the encoder 76 is AND
The signal passes through gate 25 and is stored in register 28 . Next, the calculation circuit 29 calculates the current position of the moving body 3 based on the angle data φ and φ stored in the registers 27 and 28 and the azimuth information ±θ from the positive/negative discrimination circuit 21. This calculation is performed as follows.

First, the calculation circuit 29 calculates the angles αL and α shown in FIG. 9 using the following equations (1) and (2). Incidentally, the angle α is defined by the light reflecting means 2 with the light reflecting means 2L as the apex.
It is the angle between R and the current position A of the moving body 3, and the angle α
8 is the angle between the light reflecting means 2L and the current position 11A of the moving body 3 with the light reflecting means 2R as the apex.

αL−180° −β, −φ, ... (1) α,
=180° −βk −φ, ... (2) However,
β3=90°10 and β3=90°10. Note that when calculating these angles β and β, whether to add or subtract θ from 90″ is determined by the sign of the azimuth information θ given from the positive/negative discrimination circuit 21. When the calculation is performed, the coordinate position to the current position of the moving body 3 is calculated.
9, so the angles α, and α.

It can be easily obtained from

In the embodiment described above, the direction measuring scanner 4 is used as a means for measuring the traveling direction of the moving body 3.
and the direction measuring device shown in FIG. 4, but a gyroscope, a direction magnet, etc. may be used in place of these.

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

In addition, when applying to a moving object running indoors, the light reflecting means 2R and 2L may be provided on a wall or a ceiling.

Furthermore, the present invention can also be applied to automatically MII a moving object by providing a plurality of sets of light reflecting means 2R and 2L at appropriate locations on the route that the moving object passes.

[Effects of the Invention] As described above, according to the present invention, the current position of a moving body is measured using the reflection of a light beam, so it is different from the conventional method of measuring the current position using radio waves. It has a simpler structure and is less expensive than that, is not subject to regulations under the Radio Law, and is not affected by radio noise. Further, according to the present invention, there is almost no need to perform maintenance and inspection of the light reflecting means, and the time and labor required for such maintenance and inspection can be significantly reduced.

[Brief explanation of drawings]

FIG. 1 is an illustrative diagram showing an outline of an embodiment of the present invention. FIG. 2 is a front view showing the internal structure of the orientation measuring scanner 4 shown in FIG. 1. FIG. 3 is a front view showing the internal structure of the position measuring scanner 7 shown in FIG. 1. FIG. 4 is a schematic block diagram showing the direction measuring device mounted on the moving body 3. As shown in FIG. Figures 5 and 6 show the direction measurement scanner 4.
5 is an illustrative view for explaining the direction measuring operation performed by the direction measuring device shown in FIG.
The figure shows the progress state of the moving body 3 and the positional relationship between the light reflecting means 2R and 2L, and FIG. 6 is a geometrical explanatory diagram of FIG. 5. FIG. 7 is a schematic block diagram showing a position measuring device mounted on the moving body 3. As shown in FIG. Figures 8 and 9
The figure is an illustrative diagram for explaining the current position measuring operation performed by the position measuring scanner 7 and the position measuring device shown in FIG. 7. In particular, FIG. FIG. 9 is a geometric explanatory diagram of FIG. 8. FIG. In the figure, 22 is a differentiation circuit, 23 is a T-type flip-flop, 24 and 25 are AND gates, 26 is a waveform shaping circuit, 27 and 28 are registers, 29 is an arithmetic circuit, 3
0 is a device to be used, 72 is a light source, 73 is a lens, 74 is a half mirror, 175 is a light receiver, 76 is an encoder, and 77 is a motor.

Claims (5)

[Claims] (1) A device that measures the current position of a moving object using reflection of light, the device detecting the incident light at predetermined coordinate positions on the right and left sides of the path along which the moving object should travel, respectively. first and second light reflecting means that reflect in the same direction are provided; azimuth measuring means for measuring the traveling direction of the moving object with respect to a predetermined reference direction; and rotating scanning of the light beam from the moving object. a rotary scanning means for detecting light emitted from the rotary scanning means and reflected by the first or second light reflecting means, provided in association with the rotary scanning means; a detector; angle detection means for detecting the rotation angle of the rotation scanning means; data acquisition means for taking in angle data from the angle detection means in response to the detection output of the photodetector; and a calculation means for calculating the current position of the mobile object based on the traveling direction measured by the direction measurement means and the angle data taken in by the data acquisition means. Mobile object position measuring device. (2) The position measuring device for a moving body according to claim 1, wherein the azimuth measuring means measures the azimuth using reflection of light from the light reflecting means. (3) The direction measuring means is provided in association with a light emitting means that emits light in left and right directions perpendicular to the traveling direction of the moving body, and is provided in association with the light emitting means, and the direction measuring means is provided in association with the light emitting means, a right side photodetector for detecting the light reflected by the first light reflecting means; and a right side photodetector provided in association with the light emitting means to detect the light reflected by the light emitting means, the light being emitted from the light emitting means to the second light reflecting means. a left side photodetector for detecting the light reflected by the moving object; and one of the right side and left side photodetectors detects the reflected light and the moving body a mileage measuring means for measuring the distance traveled; a mileage measured by the mileage measuring means;
and angle calculation means for calculating the traveling direction of the moving object with respect to a predetermined reference direction based on preset distance information between the first and second light reflection means. A position measuring device for a moving body according to scope 2. (4) the direction measuring means is a gyroscope;
A position measuring device for a moving body according to claim 1. (5) The moving object position measuring device according to claim 1, wherein the direction measuring means is a direction magnet.