JP2001075645A - Method and equipment for detecting position of mobing object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the equipment for detecting the position of a moving object by which the error caused by the inclination or ruggedness of a road surface is eliminated in a laser navigator system. SOLUTION: Conical retroreflectors 13 whose plane coordinates are already known are arranged in the plural parts of an area 11, and a moving object 12 is rotated and horizontally irradiated with light beams across the whole periphery, and the angle of rotation width of the light beams is measured while the recursive reflected lights of the retroreflectors 13 are detected, and the inclination of the moving object 12 is detected according to the measured angle of rotation width. Also, the plane coordinates at the present positions are measured from the angle of rotation of the light beams and the coordinate data of the retroreflectors 13 when the recursive reflected lights of the retroreflectors 13 are detected, and the plane coordinates are corrected by the detected inclination of the traveling object 12. Thus, the accurate position of the moving object 12 can be measured without being affected by the inclination or projecting/recession of the road surface can be measured, and stable traveling without being affected by the inclination or ruggedness of the road surface can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position detecting equipment for a moving body moving in a predetermined area, and more particularly to a position detecting equipment which can detect the position of a cargo handling apparatus moving in an area having an inclination or unevenness. .

[0002]

2. Description of the Related Art Conventionally, as a position detection equipment for a moving body,
The following schemes are known. . Autonomous system (dead reckoning guidance system) A means for measuring the traveling distance and the traveling direction is provided, and the position of the vehicle is calculated by integrating the traveling direction and the traveling distance.

[0003] A method based on the detected object A detection object consisting of a proximity switch, photoelectric switch, etc. is installed along the moving path of the moving object, such as a magnet or a reflective sheet, at predetermined intervals, and detects these detected objects on the moving object. Means are provided, and the position along the moving path is recognized by counting the number of detected objects.

[0004] GPS method A GPS is installed on a mobile object to recognize its own position. . Laser Navigator Method This is a method for measuring the position of a moving object from the coordinates and angles of a horizontally rotating laser and an external fixed point, which will be described with reference to FIG.

In FIG. 12, reference numeral 1 denotes an area in which the moving body 2 moves, and three areas (points A, B, and C)
A retroreflector (retroreflector) 3 is provided at (point). The retroreflector 3 is formed, for example, from a corner cube (corner reflector). A corner cube is a triangular pyramid-shaped prism composed of three flat reflecting surfaces that are orthogonal to each other as if one corner of a cube was cut off. It works to send it back in the direction of incidence.

The moving body 2 irradiates a laser beam horizontally over the entire circumference while rotating, and detects a horizontal rotation light beam (laser beam) when detecting light returned from at least three retroreflectors 3. ) Is detected and stored, and the plane coordinates of the moving body 2 (horizontal rotation light beam irradiation position) are measured based on the stored rotation angle Θ and the coordinate data of the known retroreflector 3. .

In FIG. 12, (Xm, Ym) is the moving body 2
平面 is the attitude angle of the moving body 2 from the X axis, (X
(1, Y1), (X2, Y2), (X3, Y3) are the coordinates (known) of the three retroreflectors 3 (points A, B, and C). L12 is the distance between points A and B, and L13 is the distance between points A and C.
The distance between points, Θ1 is the rotation angle when point A is detected, Θ
2 is the rotation angle when point B is detected, Θ3 is the rotation angle when point C is detected, and ε1 is the X of point B with point A as the origin.
The angle .epsilon.2 from the axis is the angle between point B and point C with point A as the origin.

The plane coordinates (Xm, Ym) of the moving body 2 and the attitude angle ψ of the moving body 2 are obtained by the following equations (1) to (10). (For details, refer to “Systems and Control” Vol. 29, No. 8 (19
85) p. See 553-560. )

[0009]

(Equation 1)

[0010]

However, the above-mentioned equipment for detecting the position of a moving object has the following problems. . Dead Reckoning Guidance Method Since a cumulative error occurs, some kind of position correction means must be provided.

[0011] Method of using a detected object A lot of cost and labor are required for installation work of a detected object, and a moving path is fixed, so that it is impossible to cope with a moving object that moves at random. . GPS method Cannot be used when the moving path of a moving object is in the shadow of a satellite, such as indoors. In other words, the reception status of GPS radio waves is not constant, and a large amount of computation is required for highly accurate position measurement. And took a long time to respond.

[0012] Laser navigator method Although it is an effective method compared to the other methods described above, the irradiation position is often set at a high position in order to avoid that the laser beam to be irradiated horizontally is blocked by an obstacle. In the case where rolling occurs due to the inclination and unevenness of the road surface, an error occurs in the measurement position (coordinate).

Accordingly, an object of the present invention is to provide a position detecting equipment in a laser navigator system in which an error due to the inclination and unevenness of a road surface is eliminated.

[0014]

According to one aspect of the present invention, there is provided a method for detecting a position of a moving body moving within a predetermined area, the method comprising the steps of: At each of a plurality of locations where the coordinates are known, a first retroreflector having a characteristic that the length of the reflection surface in the horizontal direction changes in the vertical direction is provided. Irradiating a light beam, measuring a rotation angle of the light beam when detecting the retroreflected light of the first retroreflector, and rotating the light beam while detecting the retroreflected light of the first retroreflector; Measure the angular width or the light receiving time, and calculate the inclination of the moving object based on the measured rotation angle width or the rotation speed for irradiating light rays and the light receiving time,
The plane coordinates of the current position are measured based on the measured rotation angle and the plane coordinate data of the first retroreflector, and the plane coordinates are corrected by the obtained inclination of the moving body.

According to the above method, the inclination of the moving body is determined based on the rotation angle width of the light beam or the rotation speed of irradiating the light beam and the light receiving time while detecting the retroreflected light of the first retroreflector. The plane coordinates of the current position are measured based on the rotation angle of the light beam when the retroreflected light of the retroreflector is detected and the plane coordinate data of the first retroreflector, and the plane coordinates are corrected by the obtained inclination of the moving body. .

The invention according to claim 2 is the invention according to claim 1, wherein the horizontal length of the reflection surface in the vertical direction is constant near the first retroreflector. (2) providing a retroreflector, measuring the rotation angle width or the light receiving time of the light beam while detecting the retroreflected light of the second retroreflector, and measuring the measured rotation angle width of the second retroreflector or The tilt of the moving body is detected by comparing the light receiving time with the rotation angle width of the first retroreflector or the light receiving time.

According to the above method, the inclination of the moving body is detected by comparing the rotation angle width or the light receiving time of the reference second retroreflector with the rotation angle width or the light receiving time of the first retroreflector. According to a third aspect of the present invention, there is provided a method for detecting a position of a moving body moving in a predetermined area, wherein the number of the retroreflectors changes in a vertical direction at each of a plurality of locations where plane coordinates of the area are known. A retroreflector group consisting of: is provided, and in the moving body, a light beam is irradiated horizontally over the entire circumference while rotating, and the rotation angle of the light beam when the retroreflected light of the retroreflector group is detected is measured. With
While detecting the retroreflected light of the retroreflector group, the number of the retroreflectors is measured, and the inclination of the moving body is obtained from the measured number of the retroreflectors. The present invention is characterized in that the plane coordinates of the current position are measured by the plane coordinate data of the body group, and the plane coordinates are corrected by the obtained inclination of the moving body.

According to the above method, the inclination of the moving body is obtained from the number of the retroreflectors while detecting the retroreflected light of the group of retroreflectors, and the light beam when the retroreflected light of the group of retroreflectors is detected. The plane coordinates of the current position are measured based on the rotation angle and the plane coordinate data of the retroreflector, and the plane coordinates are corrected by the obtained inclination of the moving body. Claim 4
The invention described in (1) is a method for detecting the position of a moving object moving in a predetermined area, wherein the first recursion has a characteristic that the reflectance changes in a vertical direction at a plurality of locations where the plane coordinates of the area are known. A reflector is provided, and in the moving body,
A light beam is radiated horizontally over the entire circumference while rotating, and the rotation angle of the light beam when the retroreflected light of the first retroreflector is detected is measured, and the retroreflected light of the first retroreflector is measured. The received light intensity at the time of detection is measured, the inclination of the moving body is obtained from the measured received light intensity, and the plane coordinates of the current position are measured by the measured rotation angle and the plane coordinate data of the first retroreflector. The plane coordinates are corrected based on the obtained inclination of the moving body.

According to the above method, the inclination of the moving body is obtained from the received light intensity when the retroreflected light of the first retroreflector is detected, and the light beam when the retroreflected light of the first retroreflector is detected. The plane coordinates of the current position are measured based on the rotation angle and the plane coordinate data of the first retroreflector, and the plane coordinates are corrected by the obtained inclination of the moving body. The invention according to claim 5 is the invention according to claim 4, wherein a second retroreflector having a constant reflectance in the vertical direction is provided in proximity to the first retroreflector. 2 Measure the received light intensity when detecting the retroreflected light of the retroreflector, and detect the inclination of the moving object by comparing the measured received light intensity of the second retroreflector with the received light intensity of the first retroreflector. It is characterized by doing.

According to the above method, the inclination of the moving body is detected by comparing the received light intensity of the second retroreflector serving as a reference with the received light intensity of the first retroreflector. The invention according to claim 6 is a position detecting facility for a moving body moving in a predetermined area, wherein the plane coordinates of the area are known. A first retroreflector having a characteristic in which the horizontal length of the reflection surface changes in the vertical direction is provided at each of a plurality of locations, and the moving body is irradiated with light rays horizontally over the entire circumference while rotating. Horizontal rotation light beam irradiation means, light reception means for detecting retroreflected light irradiated from the horizontal rotation light beam irradiation means and returning from the first retroreflector, and the horizontal rotation when the light reception means detects retroreflected light. The rotation angle of the light beam irradiation means, the angle detection means for measuring the rotation angle width or the light reception time of the horizontal rotation light beam irradiation means while detecting the retroreflected light by the light receiving means, and the angle detection means Tilt angle detecting means for determining the tilt of the moving object based on the rotation angle width measured or the rotation speed of irradiating the light beam and the light receiving time, the rotation angle measured by the angle detecting means and the coordinate data of the first retroreflector. Is used to measure the plane coordinates of the current position of the horizontal rotation light beam irradiation means, and correct the plane coordinates by the inclination of the moving body obtained by the inclination detection means.

According to the above configuration, the light beam is radiated to the entire periphery by the horizontal rotation light beam irradiation means, and is within the irradiation range of the light beam.
The retroreflected light of the first retroreflector is detected, the rotation angle at that time is measured, and the rotation angle width or the light receiving time during the detection of the first retroreflected light is measured. The inclination of the moving object is detected based on the angular width or the rotation speed for irradiating the light beam and the light receiving time. Then, the plane coordinates of the current position of the horizontal rotation light beam irradiation means are measured based on the measured rotation angle and the coordinate data of the retroreflector, and the plane coordinates are corrected by the detected inclination of the moving body.

The invention according to claim 7 is the invention according to claim 6, wherein the horizontal length of the reflection surface does not change in the vertical direction close to the first retroreflector in the area. (2) a retroreflector is provided, and the angle detecting means measures the rotation angle width or the light receiving time of the horizontal rotating light beam irradiating means while the light receiving means detects the light recurring from the second retroreflector, and the tilt detecting means Are the measured first retroreflector and the second
The tilt of the moving body is detected by comparing the rotation angle width or the light receiving time while detecting the retroreflected light of the retroreflector.

According to the above configuration, the distance between the moving object and the retroreflector is determined by comparing the rotation angle width or the light receiving time of the reference second retroreflector with the rotation angle width or the light receiving time of the first retroreflector. Instead, the position of the first retroreflector irradiated in the vertical direction is specified, and the inclination of the moving body is accurately measured. The invention according to claim 8 is the invention according to claim 6 or claim 7, wherein the shape of the first retroreflector is a cone, an inverted cone, a triangular pyramid, or an inverted triangular pyramid. It is characterized by having done.

According to the above configuration, the rotation angle width or the light receiving time when the retroreflected light is detected changes depending on the vertical direction of the retroreflector. Therefore, the height of the retroreflector to which the light beam is irradiated is obtained from the rotation angle width or the light receiving time, and the inclination of the moving body is detected from the height. According to a ninth aspect of the present invention, there is provided a position detecting equipment for a moving body moving in a predetermined area, wherein the number of retroreflectors whose number in the vertical direction changes at a plurality of locations where the plane coordinates of the area are known is changed. A horizontal rotating light irradiating means for irradiating the moving body with light horizontally over the entire circumference while rotating, and irradiating the moving body with the horizontal rotating light irradiating means and returning from the retroreflector. Light receiving means for detecting the light, the angle detecting means for measuring the rotation angle of the horizontal rotation light beam irradiating means when detecting the light returned by the light receiving means, when detecting the light returned by the light receiving means, The number of retroreflectors in the group of retroreflectors is provided, and inclination detecting means is provided for detecting the inclination of the moving body based on the measured number of retroreflectors, and the rotation measured by the angle detecting means is provided. The plane coordinates of the current position of the horizontal rotation light beam irradiating means are measured based on the degree and the coordinate data of the retroreflector, and the plane coordinates are corrected based on the inclination of the moving body detected by the inclination detecting means. Things.

With the above structure, the light beam is radiated to the entire periphery by the horizontal rotation light beam irradiation means, and is within the irradiation range of the light beam.
The retroreflected light of the group of retroreflectors is detected, the rotation angle at that time is measured, and the number of retroreflectors in the group of retroreflectors is measured.
The inclination of the moving object is detected. Then, based on the measured rotation angle and the coordinate data of the retroreflector group, the plane coordinates of the current position of the horizontal rotation light beam irradiation means are measured, and the plane coordinates are corrected by the detected inclination of the moving body.

According to a tenth aspect of the present invention, there is provided a position detecting equipment for a moving body moving in a predetermined area, wherein the reflectance changes in a vertical direction at each of a plurality of locations where the plane coordinates of the area are known. A first retroreflector having characteristics, a horizontal rotating beam irradiating means for irradiating the moving body with a beam of light horizontally around the entire circumference while rotating, and the first retroreflector irradiated by the horizontal rotating beam irradiating means; Detecting retroreflected light that has returned from the reflector, detecting light receiving intensity at that time, and detecting an angle of rotation of the horizontally rotating light irradiating means when detecting retroreflected light by the light receiving means. Means, and inclination detecting means for detecting the inclination of the moving body based on the received light intensity of the retroreflected light detected by the light receiving means. The rotation angle measured by the angle detecting means and the first The present invention is characterized in that the plane coordinates of the current position of the horizontal rotation light beam irradiation means are measured based on the coordinate data of the reflector, and the plane coordinates are corrected by the inclination of the moving body detected by the inclination detection means. .

With the above arrangement, the light beam is radiated to the entire periphery by the horizontally rotating light beam irradiation means, and is within the irradiation range of the light beam.
The retroreflected light of the retroreflector is detected, the rotation angle at that time is measured, and the received light intensity is measured, and the inclination of the moving object is detected based on the measured received light intensity. Then, the plane coordinates of the current position of the horizontal rotation light beam irradiation means are measured based on the measured rotation angle and the coordinate data of the retroreflector, and the plane coordinates are corrected by the detected inclination of the moving body.

According to an eleventh aspect of the present invention, in accordance with the tenth aspect of the present invention, a second retroreflector having a constant vertical reflectance is provided near the first retroreflector in the area. The light receiving means measures the light receiving intensity of the retroreflected light returned from the second retroreflector, and the inclination detecting means detects the retroreflected light of the first retroreflector and the second retroreflector detected by the light receiving means. The inclination of the moving object is detected by comparing the received light intensities.

With the above configuration, the first retroreflector can be used even in an environment where the received light intensity changes due to rain, fog, etc., by comparing the received light intensity of the retroreflected light from the first retroreflector and the second retroreflector. The irradiated vertical position is specified,
The inclination of the moving object is accurately measured. The invention according to claim 12 is the invention according to claim 10 or 11, wherein the first retroreflector is a retroreflector having a constant reflectance in the vertical direction, and the first retroreflector is provided with a light beam in the vertical direction. The present invention is characterized in that filters having different absorptivity are attached to each other.

According to the above configuration, a first retroreflector whose reflectance changes in the vertical direction is formed. The invention according to claim 13 is the invention according to claim 10 or claim 11, wherein the first retroreflector is constituted by a retroreflector having different colors in the vertical direction. It is. With the above configuration, the first type in which the reflectance changes in the vertical direction
A retroreflector is formed.

[0031]

Embodiments of the present invention will be described below with reference to the drawings. [Embodiment 1] FIG. 1 is a plan view of an area provided with facilities for detecting a position of a moving body according to Embodiment 1 of the present invention.

In FIG. 1, reference numeral 11 denotes an area (for example, a warehouse, a factory, a port, or the like) in which a moving body (for example, a forklift or an automatic guided vehicle) 12 moves. On the outer periphery of the area 11, an inverted conical retroreflector (retroreflective light reflector) 13 having a reflection characteristic of reflecting light rays having an incident angle within a range of ± 45 ° in the incident direction as shown in FIG. However, a plurality of them are installed on a wall (or a column) at the same height from the reference plane of the area 11 with its central axis vertical. In addition, these retroreflectors 13 have their plane coordinates set in advance, and the retroreflectors 13 have an inverted conical shape so that any moving body 12 traveling on a plane can see the same shape. The retroreflector 13 may have any shape in which the horizontal length of the reflection surface changes in the vertical direction, and the shape may be a conical shape, a triangular pyramid shape, or an inverted triangular pyramid shape. What is necessary is just to be able to prepare a table of data of the horizontal length of the reflecting surface that changes.

The structure of the moving body 12 will be described with reference to FIG. A horizontal rotating beam irradiating means for generating a laser beam and irradiating the laser beam horizontally over the entire circumference while rotating the laser beam, and a light receiving device for detecting light radiated from the horizontal rotating beam irradiating means and returned from the retroreflector Means, the rotation angle of the horizontal rotation light beam irradiation means when detecting the light returned by the light receiving means, and the rotation angle width of the horizontal rotation light irradiation means while detecting the light returned by the light reception means Angle detection means for measuring the angle of rotation, inclination detection means for detecting the inclination of the moving object based on the rotation angle width measured by the angle detection means, the rotation angle and the coordinates of the retroreflector measured by the angle detection means According to the data,
Measure the plane coordinates of the current position of the horizontal rotation light beam irradiation means,
Position measuring means for correcting the plane coordinates based on the inclination of the moving object detected by the inclination detecting means is provided.

The horizontal rotating beam irradiating means includes a semiconductor laser device 21 for horizontally irradiating the laser beam, a half mirror 22 for vertically guiding the laser beam emitted from the semiconductor laser device 21 upward, a laser beam and retroreflection. A vertical cylindrical conduit 23 that serves as a path for the retroreflected light of the body 13 (light that has been returned from the retroreflector), and the conduit 23 is connected below the center and is mounted on a ring-shaped bearing 24. A cylindrical body 25, a reflecting mirror 26 disposed in the cylindrical body 25, for reflecting a laser beam guided from the conduit 23 in a horizontal direction and guiding the laser beam to a window 25A provided on a side surface of the cylindrical body 25; Fitting around 23 and conduit
It comprises a first gear 27 for rotating the motor 23, a DC motor 28, and a second gear 29 which is directly connected to the rotating shaft of the DC motor 28 and meshes with the first gear 27. The height of the laser beam emitted from the cylinder 25 of the moving body 12 located on the reference plane of the area 11 is made to coincide with the center of the retroreflector 13 in the height direction.

With this configuration, the laser beam emitted horizontally from the semiconductor laser device 21 is guided upward by the half mirror 22. When the DC motor 28 is driven, the rotational force of the DC motor 28 is transmitted through the second gear 29 and the first gear 27 to the conduit 23.
Is transmitted to the conduit 23, and the reflecting mirror 26 is rotated together with the cylindrical body 25. The laser beam guided into the conduit 23 is rotated by the reflecting mirror 26 so that the center position of the conduit 23 (cylindrical body 25) is adjusted. Irradiation is performed on the entire circumference of the moving body 12 with the center as the center.

The light receiving means includes a light receiving sensor 31 on which the retroreflected light of the retroreflector 13 guided through the reflection mirror 26 and the conduit 23 and the half mirror 22 enters, and a photocurrent signal of the light receiving sensor 31. The light receiving detector 32 detects the retroreflected light of the retroreflector 13 and outputs a light receiving signal. With the above configuration, the reflection mirror 26 is rotated by the rotation of the conduit 23, and the retroreflected light of the retroreflector 13 guided through the reflection mirror 26 is reflected by the conduit 23 and the half mirror 22.
Then, the retroreflected light of the retroreflector 13 is detected by the light receiving detector 32 based on the photocurrent signal of the light receiving sensor 31, and the light receiving signal is output.

The angle detecting means is connected to the conduit 23,
An encoder 41 that generates a pulse by rotation of the conduit 23,
The pulse signal output from the encoder 41 is added to measure the rotation angle (irradiation angle of the laser beam) Θ of the reflection mirror 26 that sets the traveling direction to 0 °. A mirror rotation angle detector 42 measures and outputs the rotation angle Θ and the rotation angle width φ while the light receiving signal is being input.

According to this configuration, the rotation angle (irradiation angle of the laser beam) of the reflection mirror 26 when a light reception signal is input from the light reception detector 32 and the rotation angle width φ during light reception are determined by the mirror rotation angle detector. Detected by 42. The tilt detecting means and the position measuring means comprise a controller 45 composed of a computer and a reflector coordinate storage unit 46 in which the plane coordinates of each retroreflector 13 are stored.

The controller 45 receives the rotation angle Θ and the rotation angle width φ from the mirror rotation angle detector 42.
First, a method of detecting the inclination of the moving body 12 by the controller 45 will be described. As shown in FIG. 3, when the moving body 12 is tilted, the laser beam applied to the center of the retroreflective body 13 in the height direction shifts in the vertical direction due to the tilt. As shown in FIG. 2, the range in which the retroreflected light of ± 45 ° returns when the light beam is shifted in the vertical direction (reflection width).
Changes. Since the retroreflector 13 has an inverted conical shape, if it is shifted upward, its reflection width becomes wider, that is, the rotation angle width φ2 while the retroreflected light is received by the light receiving sensor 31 and the light receiving detector 32. Is wider than the rotation angle width φ0 at the center in the height direction, and conversely, if it is shifted downward, the reflection width becomes narrow, that is, the rotation while the retroreflected light is received by the light receiving sensor 31 and the light receiving detector 32. The angle width φ1 is smaller than the rotation angle width φ0 at the center in the height direction.

When the distance between the laser beam irradiation center position (the center of the cylindrical body 25 of the horizontally rotating light beam irradiation means) and the center position of the retroreflector 13 is L, the cone detection width W is L≫W. Therefore, it can be obtained by equation (11). W {2Ltan (φ / 2) (11) Note that the distance L is the plane coordinate {Xv (t−1), Yv (t−1)} of the previous measurement of the horizontal rotation light beam irradiation unit, and the moving body 12 And the known plane coordinates (X) of the retroreflector 13 estimated from the orientation of the retroreflector 13 and the rotation angle Θ when the retroreflector 13 is detected.
r, Yr).

When the cone detection width W is determined, as shown in FIG. 4, when the cone height of the retroreflective body 13 is 2 h and the maximum width (bottom width) of the cone is Wmax, irradiation from the center height position is performed. The height displacement Δh is obtained by Expression (12). Δh = h (2W / Wmax−1) (12) When the spread width α of the laser beam cannot be ignored, when the cone width at the center height position is W0, the irradiation height displacement Δ
h is obtained by equation (12) ′.

Δh = h (W−W0−α) / W0 (12) ′ Note that the spread width α of the laser beam is obtained by α = 2Ltan (spread angle / 2). Further, the spread width α of the laser beam with respect to the distance L can be stored in advance.

The controller 45 calculates the three positions (points A, B, and C) where the retroreflector 13 shown in FIG. 5 is installed by using the equations (11) and (12) or (12) ′. The irradiation height displacements Δh1, Δh2, and Δh3 are obtained from the respective rotation angle widths φ and stored. Next, the plane coordinates of the current position of the horizontally rotating light beam irradiation means (the center position of the cylindrical body 35) in a state where the moving body 12 is inclined are obtained. This calculation is performed at three points (points A, B, C
The detection angles Θ1, Θ2, Θ3 of the retroreflector 13 and the known coordinates (X1, Y1), (X2,
Y2) and (X3, Y3), the above equations (1) to (1)
0).

In FIG. 5, (Xm, Ym) is the moving body 12
Is the plane coordinates of the current position of the horizontally rotating light beam irradiating means in a state where is inclined. Coordinates (Xv, Y
v) is the calculated coordinates (X
m, Ym) by three irradiation height displacements Δh1, Δh2, Δh3 (points A, B, C),
It is obtained by the following equations (13) to (20). z0 is a cylinder
The irradiation height of the laser beam irradiated from 25 (the center height of the retroreflector 13 from the reference plane).

[0045]

(Equation 2) By the configuration and the calculation of the controller 45, the irradiation height displacement Δh of the irradiation position of the laser beam is obtained from the rotation angle width φ measured by the mirror rotation angle detector 42, and then the moving body 12 is tilted. The coordinates (Xm, Ym) of the horizontally rotating light emitting means in the state are obtained, and the coordinates (Xm, Ym) are corrected by the irradiation height displacement Δh, and the coordinates (Xv, Ym) of the horizontally rotating light emitting means on the horizontal plane are obtained.
v) is required. The obtained coordinates (Xv, Yv)
Is output to the steering controller 50, and the moving body 12 is guided according to a preset route.

According to the configuration of the above-described equipment, an inverted conical retroreflector whose plane coordinates are known is provided at a plurality of locations in the area 11.
The rotation measured by the mirror rotation angle detector 42 when irradiating light rays horizontally over the entire circumference while rotating from the moving body 12 and detecting the retroreflected light of the retroreflector 13 is provided. From the angle width φ, the irradiation height displacement Δh (inclination of the moving body 12) is measured, and the rotation angle の of the light beam when the retroreflected light of the retroreflector 13 is detected and the coordinate data of the known retroreflector 13 Thus, the plane coordinates (Xm, Ym) of the horizontally rotating light beam irradiation means in a state where the moving body 12 is inclined due to the inclination and unevenness of the road surface of the area 11 are measured, and the plane coordinates (Xm
m, Ym) is corrected by the detected irradiation height displacement Δh, whereby the coordinates (Xv, Yv) of the horizontally rotating light beam irradiation means on the horizontal plane are obtained.

As described above, the coordinates (Xv, Yv) of the horizontally rotating light beam irradiating means on the horizontal plane can be obtained, so that accurate position measurement of the moving body 12 can be performed without being affected by the inclination and unevenness of the road surface. As a result, the vehicle can run stably without being affected by the inclination and unevenness of the road surface. In addition, since accurate guidance is possible by accurate position measurement of the moving body 12, cargo handling position accuracy is improved, and stable cargo handling work can be performed,
Furthermore, contact with the installed machine or the like can be prevented, and safety can be ensured.

In the first embodiment, the distance L between the moving body 12 and the retroreflector 13 needs to be calculated.
As shown in FIG. 3, a cylindrical shape (a cylindrical shape may be used) adjacent to a conical retroreflector (referred to as a first retroreflector) 13 having the same width as the conical width at the height center of the first retroreflector 13. The second retroreflector 14) is provided, and the rotation angle width φ0 when the second retroreflector 14 is detected is measured and used as a reference, so that it is not necessary to calculate the distance L. it can.
At this time, assuming that the irradiation height displacement from the center height position is Δh, the irradiation height displacement can be obtained by Expressions (21) to (24).

Δh = h (W / W0−1) (21) W0 = 2Ltan (φ0 / 2) (22) W = 2Ltan (φ / 2) (23) Δh = h ｛tan (φ / 2) ) / Tan (φ0 / 2) -1｝ (24) [Second Embodiment] In the second embodiment, the first embodiment is used.
A retroreflector group 51 shown in FIG.

As shown in FIG. 7, a group of retroreflectors 51, one columnar retroreflector 52 is provided at the first stage, two at the second stage, and two at the third stage. The third, fourth and fourth rows are arranged in an inverted conical shape, with the fourth and fifth rows being spaced apart. As shown in FIG. 8, when a light receiving signal (pulse signal) of the light receiving detector 32 is newly input to the moving body 12 in the first embodiment, a predetermined time,
A counter 33 is provided which counts a pulse signal input within a time for scanning the retroreflector 52. Counter 33
Are output to the controller 45.

According to the configuration of the retroreflector group 51, when the laser beam that irradiates the retroreflector group 51 shifts in the vertical direction due to the inclination of the moving body 12, the light received by the light detector 32 input to the counter 33 is received. The number of signals changes. Therefore, the controller 45 uses the count value input from the counter 33 to
As shown in FIG. 7, the irradiation height displacement Δ from the center height position
h can be determined, and the plane coordinates of the moving body 12 can be corrected based on the irradiation height displacement Δh. [Third Embodiment] In a third embodiment, the first embodiment will be described.
The retroreflector shown in FIG.
61 are provided.

As shown in FIG. 9, a retroreflector 61 is formed by attaching filters 63 of a predetermined width different in transmittance in the vertical direction to a cylindrical (or cylindrical) retroreflector 62 in the vertical direction. The reflectivity is changed. The filter
As the 63, for example, an ND filter (a filter for attenuating white light) is used. Further, as shown in FIG. 10, in the moving body 12 in the first embodiment, the intensity of the photocurrent signal of the light receiving sensor 31, that is, the light receiving intensity is newly measured by the light receiving detector 32, and the received light intensity is sent to the controller 45. The function to output is added.

According to the configuration of the retroreflector 61, the moving body
When the laser beam that irradiates the retroreflector 61 due to the inclination to 12 shifts in the vertical direction, the reflectance of the retroreflector 61 changes, so that the light receiving intensity of the retroreflected light detected by the light receiving sensor 31 and the light receiving detector 32 Changes. Therefore, the controller 45 determines the irradiation height displacement Δh from the center height position based on the received light intensity of the retroreflected light measured by the light receiving detector 32.
Can be determined, and the plane coordinates of the moving body 12 can be corrected based on the irradiation height displacement Δh.

In the third embodiment, the filter 63 is attached to the cylindrical retroreflector 62 in order to change the reflectivity up and down. The retroreflectors 61 (which may be columnar) may be stacked in the vertical direction to form the retroreflectors 61. Further, as shown in FIG. 11, a cylindrical (or may be a cylindrical) second retroreflector adjacent to the retroreflector 61 and having the same reflectance as the reflectance at the height center of the retroreflector 61 as a whole. 64, the received light intensity of the retroreflected light of the second retroreflector 64 is measured, and the received light intensity of the retroreflected light of the retroreflector 61 is compared with the received light intensity of the retroreflected light of the second retroreflector 64. By doing
The irradiation height displacement Δh from the center height position can be determined. According to this method, the irradiation height displacement Δh in the vertical direction of the laser beam irradiated on the first retroreflector 61 can be accurately measured even in an environment in which the received light intensity changes due to rain, fog, and the like. 12 inclinations can be measured accurately.

In the first to third embodiments, a laser beam is used. However, the present invention is not limited to a laser beam, and any light beam having a straight traveling property may be used. Further, although the retroreflectors 13 and 61 or the retroreflector group 51 are arranged on the outer periphery of the area 11, it is not always necessary to arrange them on the outer periphery, and they can be arranged in the area 11. In addition, in the angle detection means, the pulse signal output from the encoder 41 is added to measure the rotation angle width φ, but since the rotation speed is known,
The rotation angle width may be obtained by measuring the time during which the light receiving signal is input, that is, the light receiving time.

[0056]

As described above, according to the present invention, it is possible to detect the inclination of the moving body due to the inclination and unevenness of the road surface, and to correct the plane coordinates of the current position of the horizontally rotating light beam irradiation means based on this inclination. By doing so, accurate plane coordinates can be obtained.

[Brief description of the drawings]

FIG. 1 is a plan view of an area provided with mobile object position detection equipment according to Embodiment 1 of the present invention.

FIG. 2 is an explanatory diagram of a retroreflector in a moving object of the moving object position detection equipment.

FIG. 3 is a configuration diagram of a position detection facility of the moving body.

FIG. 4 is an explanatory diagram for obtaining an irradiation height displacement from a reflection width of a retroreflector in the mobile object position detection equipment.

FIG. 5 is an explanatory diagram of a method for calculating a position of the moving object in the position detecting equipment of the moving object.

FIG. 6 is a perspective view showing the shapes and arrangements of two retroreflectors of the mobile object position detection equipment.

FIG. 7 is an explanatory diagram of a retroreflector of a moving object position detection facility according to Embodiment 2 of the present invention.

FIG. 8 is a configuration diagram of a position detection facility of the moving body.

FIG. 9 is an explanatory diagram of a retroreflector of a mobile object position detection facility according to Embodiment 3 of the present invention.

FIG. 10 is a configuration diagram of a position detection facility of the moving body.

FIG. 11 is a perspective view showing the shapes and arrangements of two retroreflectors of the mobile object position detection equipment.

FIG. 12 is an explanatory diagram of a position calculation method of a conventional moving object in a moving object of the position detecting equipment for the moving object.

[Explanation of symbols]

 11 Area 12 Moving body 13 (1) Retroreflector 14, 64 (2) Retroreflector 21 Semiconductor laser device 22 Half mirror 23 Conduit 25 Tube 26 Reflector mirror 27, 29 Gear 28 DC motor 31 Light receiving sensor 32 Light receiving Detector 33 Counter 41 Encoder 42 Mirror rotation angle detector 45 Controller 51 Retroreflector group 52, 61, 62 Retroreflector 63 Filter A, B, C Position of retroreflector

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoichiro Nakamura 1-89, Minamikohoku, Suminoe-ku, Osaka-shi, Osaka Inside Hitachi Zosen Corporation (72) Inventor Hirotoshi Shimoda 1-chome, Minamikohoku, Suminoe-ku, Osaka-shi, Osaka 7-89 Inside Hitachi Zosen Corporation (72) Inventor Shigeki Ueda 1-15-10 Kyomachibori, Nishi-ku, Osaka-shi, Osaka TMC-M Corporation (72) Inventor Koichi Saito, Kyomachi, Nishi-ku, Osaka, Osaka Hori 1-chome No.15-10 TMC M Co., Ltd. F term (reference) 2F065 AA03 AA37 BB15 CC11 EE00 FF23 FF31 FF66 GG06 GG12 JJ01 LL00 LL13 LL16 LL62 MM16 QQ23 5H301 BB05 FF06 FF11 FF26 GG08

Claims (13)

[Claims] 1. A method for detecting a position of a moving body moving in a predetermined area, wherein a horizontal length of a reflecting surface changes in a vertical direction at each of a plurality of locations where plane coordinates of the area are known. A first retroreflector having the following is provided. In the moving body, a light beam is irradiated horizontally over the entire circumference while rotating, and the rotation angle of the light beam when the retroreflected light of the first retroreflector is detected is set. While measuring and measuring the rotation angle width or the light receiving time of the light beam while detecting the retroreflected light of the first retroreflector, the measured rotation angle width or the rotation speed and the light receiving time for irradiating the light beam are measured. Calculating the inclination of the moving body based on the above, measuring the plane coordinates of the current position based on the measured rotation angle and the plane coordinate data of the first retroreflector, and correcting the plane coordinates by the obtained inclination of the moving body. Position detection method for a mobile body according to claim. 2. A second retroreflector having a constant vertical length of a reflecting surface in a vertical direction in proximity to the first retroreflector, and detecting retroreflected light of the second retroreflector. The rotation angle width or the light reception time of the light beam during the measurement is measured, and the moving object is compared by comparing the measured rotation angle width or the light reception time of the second retroreflector with the rotation angle width or the light reception time of the first retroreflector. 2. The method according to claim 1, wherein the inclination of the object is detected.
3. The method for detecting the position of a moving object according to 1. 3. A method of detecting a position of a moving body moving within a predetermined area, comprising: a retroreflector comprising a plurality of retroreflectors whose number in the vertical direction changes at a plurality of locations where plane coordinates of the area are known. In the moving body, while irradiating a light beam horizontally over the entire circumference while rotating, and measuring the rotation angle of the light beam when the retroreflected light of the retroreflector group is detected, the retroreflection The number of the retroreflectors is measured while detecting the retroreflected light of the body group, the inclination of the moving body is determined by the measured number of the retroreflectors, and the measured rotation angle and the retroreflector group are measured. A method for detecting a position of a moving body, comprising: measuring plane coordinates of a current position based on plane coordinate data; and correcting the plane coordinates based on the obtained inclination of the moving body. 4. A method for detecting a position of a moving body moving in a predetermined area, wherein the first retroreflection has a characteristic that a reflectance changes in a vertical direction at each of a plurality of locations where plane coordinates of the area are known. Provide a body, in the moving body, while irradiating a light beam horizontally over the entire circumference while rotating, while measuring the rotation angle of the light beam when the retroreflected light of the first retroreflector is detected, (1) The received light intensity of the retroreflector when detecting the retroreflected light is measured, the inclination of the moving body is obtained from the measured received light intensity, and the measured rotation angle and the plane coordinate data of the first retroreflector are used. A method of detecting a position of a moving object, comprising: measuring plane coordinates of a current position, and correcting the plane coordinates based on the obtained inclination of the moving object. 5. A light receiving intensity when a second retroreflector having a constant reflectance in the vertical direction is provided close to the first retroreflector, and retroreflected light of the second retroreflector is detected. 5. The position detection of the moving body according to claim 4, wherein the inclination of the moving body is detected by comparing the measured light receiving intensity of the second retroreflector with the measured light receiving intensity of the first retroreflector. Method. 6. A position detecting equipment for a moving body moving within a predetermined area, wherein a horizontal length of a reflecting surface changes in a vertical direction at each of a plurality of locations where plane coordinates of the area are known. A first retroreflective body having: a horizontal rotating light beam irradiating means for irradiating the moving body with a light beam horizontally around the entire circumference while rotating; and the first retroreflecting light irradiated from the horizontal rotating light beam irradiating means. Light-receiving means for detecting retroreflected light that has returned from the body; rotation angle of the horizontal rotation light beam irradiating means when the retroreflected light is detected by the light-receiving means; and while detecting retroreflected light by the light-receiving means. Angle detection means for measuring the rotation angle width or the light receiving time of the horizontal rotation light beam irradiation means, and the rotation angle width or the rotation speed and the light reception time for irradiating the light rays measured by the angle detection means. Tilt detecting means for obtaining the tilt of the moving object based on the rotation angle measured by the angle detecting means and the first
The coordinate data of the retroreflector is used to measure the plane coordinates of the current position of the horizontally rotating light beam irradiating means, and the plane coordinates are corrected by the inclination of the moving body obtained by the inclination detecting means. Position detection equipment. 7. An area is provided with a second retroreflector close to the first retroreflector in which the length of the reflection surface in the vertical direction does not change in the vertical direction, and the angle detecting means is provided with a second retroreflector by the light receiving means. The rotation angle width or the light receiving time of the horizontally rotating light beam irradiating means is measured while detecting the light returning from the body, and the inclination detecting means measures the retroreflections of the measured first and second retroreflectors. The moving object position detecting apparatus according to claim 6, wherein the inclination of the moving object is detected by comparing a rotation angle width or a light receiving time while detecting light. 8. The position of the moving object according to claim 6, wherein the first retroreflector has a conical shape, an inverted conical shape, a triangular pyramid shape, or an inverted triangular pyramid shape. Detection equipment. 9. A facility for detecting the position of a moving body that moves within a predetermined area, wherein the retroreflector includes a plurality of retroreflectors whose number in the vertical direction changes at a plurality of locations where the plane coordinates of the area are known. A horizontal rotation light beam irradiating means for irradiating the moving body with a light beam horizontally over the entire circumference while rotating, and detecting light radiated from the horizontal rotation light beam irradiating means and returned from the retroreflector. A light receiving means for detecting, the angle detecting means for measuring the rotation angle of the horizontal rotation light beam irradiating means when detecting the light returned by the light receiving means, and the retroreflector when detecting the light returned by the light receiving means The number of the retroreflectors in the group is measured, and inclination detecting means for detecting the inclination of the moving object is provided based on the measured number of the retroreflectors. The rotation angle and the rotation angle measured by the angle detecting means are provided. A moving body that measures plane coordinates of the current position of the horizontal rotation light beam irradiation means based on the coordinate data of the retroreflector, and corrects the plane coordinates based on the inclination of the moving body detected by the inclination detection means; Position detection equipment. 10. A facility for detecting the position of a moving body moving in a predetermined area, wherein the first retroreflection has a characteristic that the reflectance changes in a vertical direction at each of a plurality of locations where the plane coordinates of the area are known. A horizontal rotating light beam irradiating means for irradiating the moving body with a light beam horizontally over the entire circumference while rotating; and a retroreflection irradiated from the horizontal rotating light beam irradiating means and returned from the first retroreflector. Detecting light, light receiving means for detecting the received light intensity at that time, angle detecting means for measuring the rotation angle of the horizontal rotation light beam irradiating means when the retroreflected light is detected by the light receiving means, and the light receiving means Tilt detection means for detecting the tilt of the moving body based on the intensity of the detected retroreflected light; and the rotation angle measured by the angle detection means and the first
A moving body that measures plane coordinates of the current position of the horizontal rotation light beam irradiation means based on the coordinate data of the retroreflector, and corrects the plane coordinates based on the inclination of the moving body detected by the inclination detection means; Position detection equipment. 11. A second retroreflector having a constant reflectance in the vertical direction in proximity to the first retroreflector in the area, and a light receiving means for receiving the retroreflected light retroreflected from the second retroreflector. The intensity is measured, and the inclination detecting means detects the inclination of the moving body by comparing the received light intensity of the retroreflected light of the first retroreflector and the second retroreflector detected by the light receiving means. Item 1
0 The position detection equipment of a moving body of 0. 12. The first retroreflector according to claim 10, wherein the first retroreflector has a constant reflectivity in the vertical direction and a filter having a different light absorptivity in the vertical direction attached to the retroreflector. The position detection equipment for a moving body according to claim 11. 13. The moving object position detecting equipment according to claim 10, wherein the first retroreflector is constituted by retroreflectors having different colors in the vertical direction.