JPH08211936A - Guiding device for traveling object - Google Patents

Abstract

PURPOSE: To guide a traveling object along a set moving route by performing autonomous movement due to dead reckoning while using a jyro and a moving distance measuring instrument when a marker does not exist in the visual field of a camera because of an obstacle, etc. CONSTITUTION: A traveling object 3 is controlled so as to be moved toward a marker 12 whose image is picked up by a camera 7 for visual guidance fitted downward obliquely in the advancing direction and when the marker 12 comes just under the traveling object 3, the traveling object is moved to the next route by recognizing the marker 12 with a camera 8 for route recognition fitted vertically downward. With this movement, it is decided that the marker 12 does not exist in the visual fields of the cameras 7 and 8 for visual guidance and route recognition because of any obstacle, etc., and the autonomous movement due to dead recknoning is performed while using a jyro 14 and the moving distance measuring instrument. Thus, the traveling object 3 can be guided along the set moving route and trouble for maintenance management can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving body guiding apparatus for guiding a moving body used in an automated guided vehicle used in factories or offices along a set route.

[0002]

2. Description of the Related Art In recent years, the need for automated guided vehicles has increased with the labor saving in factories and offices.
In fact, the movement to introduce automated guided vehicles is becoming more active. In an automatic guided vehicle, it is necessary to guide a moving body along a preset route, and in addition to the accuracy of this guidance, a guidance device that can flexibly cope with route changes is required.

Conventionally, as a method for guiding a moving body such as this automatic guided vehicle, an optical tape type, an optical laser type and the like have been devised. (1) A conventional optical tape type guiding method is shown in FIGS.
Will be explained.

As shown in FIG. 14, the optical tape 1 is continuously attached along the set path of movement. As shown in FIG. 15, the moving body 3 is installed on the optical tape 1 so that the tape is located at the center of the screen of the camera 2 installed on the moving body 3.

With the movement of the moving body 3, by controlling the steering of the moving body 3 so that the optical tape 1 is always located at the center of the camera image 4, the moving body 3 moves along the optical tape 1. . (2) An optical laser type guiding method will be described with reference to FIGS.

As shown in FIG. 16, a laser lighthouse 5-2 for emitting a laser beam 5-1 in all directions of 360 ° is mounted on a moving body, and reflectors 6 for reflecting the laser beam 5-1 are provided at both ends of the orbit. Place along.

The coordinates of the reflector 6 are held as a map. Laser light 5 emitted from laser lighthouse 5-2
-1 is reflected by the reflector 6 and again the laser lighthouse 5-
2 and outputs the angles at which the reflector 6 exists with respect to the moving body 3 (angles at which the reflector 6 exists: θ1, θ2).

As shown in FIG. 17, since the coordinates of the reflector 1 and the reflector 2 are known, a triangular circumscribed circle C1 composed of the reflector 1, the reflector 2 and the moving body is calculated from the coordinates and θ1.

Similarly, the circumscribed circle C2 is calculated from θ2 and the coordinates of the reflector 1 and the reflector 3. When the intersection of C1 and C2 is obtained, one intersection becomes the coordinates of the reflector 1 and the other intersection becomes the coordinates of the moving body. In this way, the position of the moving body can be detected, and the moving body is guided based on that position.

[0010]

However, in the conventional optical tape type, since the optical tape is attached to the entire route, when the route is changed, the optical tape must be reattached. It takes time to change.

Further, since the tape is continuously applied to the floor, stains, scratches, and breaks are likely to occur, and the width of the optical tape changes, so that the center of the tape becomes curved and the moving body fluctuates, Due to the interruption of the tape, there is a problem that the optical tape may be lost on the way and become out of control.

Further, in the conventional optical laser type, since the installation accuracy of the reflector has a great influence on the position / orientation detection accuracy of the moving body, the installation is very strict, resulting in an increase in the installation cost of the reflector. .

In addition, when the route is changed, the reflector has to be installed again, and as a result, the cost for changing the route becomes very high, so that the route cannot be changed easily. was there.
It is an object of the present invention to provide a moving body guiding apparatus that can solve these problems.

[0014]

A guiding device for a moving body according to the present invention is a guiding device for guiding a moving body 3 along a predetermined route, in which (A) it is attached along the moving route, and A marker indicating an attribute, (B) a visual guidance camera mounted obliquely downward in the traveling direction, (C) a route recognition camera mounted vertically downward, and (D) obtained with the two cameras. An image processor that recognizes a marker from an image, (E) a controller that determines the traveling direction of a moving body from the recognition result, (F) a steering mechanism that controls the traveling direction of the moving body, and (G) a moving body. A drive mechanism for moving the
(H) A moving distance measuring device for measuring a moving distance of a moving body,
(I) A gyro that measures the posture of the moving body, and (J) a storage device that stores the position of the marker as a map, (K)
The moving body is controlled so as to move toward the marker imaged by the visual guidance camera, and when the marker comes directly under the moving body, the route recognition camera recognizes the marker and moves on the next route. When the marker does not exist in the camera's field of view due to a snowfall, obstacle, etc., it moves along the set movement path by performing dead reckoning (position estimation) using a gyro and a movement distance measuring device. It is characterized by inducing the body.

[0015]

Operation: Markers having route attributes such as left turn, right turn, cross road, T-shaped road, straight ahead, and stop are pasted along the set trajectory, and the coordinates of the markers are registered as a map in the storage device.

A visual guidance camera and a route recognition camera are mounted on the moving body, and the marker is imaged by the visual guidance camera while moving the moving body. The image of the visual guidance camera is input to the image processor.

When the moving body is directed straight toward the marker, the marker is located at the left and right center of the image,
When the traveling direction is deviated, the marker is displaced from the horizontal center of the screen, so the image processor detects the amount of the displacement.

The detection result of the image processor is input to the controller, and the steering angle is determined so that the amount of deviation from the center of the left and right becomes zero. This steering angle is input to the steering mechanism and moved by the moving mechanism while controlling the steering.

During the movement, the measurement results of the movement distance measuring device and the gyro are input to the controller to calculate the position of the moving body. When the marker disappears from the field of view of the camera due to an obstacle, it moves autonomously by dead reckoning (position estimation) using a moving distance measuring device and a gyro. Then, when the marker appears again, the visual guidance is restarted.

When the marker comes directly under the route recognition camera, its image is input to the image processor. The image processor recognizes the attribute of the marker, simultaneously detects the position and the inclination of the marker on the image, and inputs the result to the controller. The controller collates the position of the moving body measured by the moving distance measuring device and the gyro with the map of the marker stored in the storage device to determine the next route. At the same time, the gyro and the moving distance measuring instrument are calibrated from the position and the inclination of the marker on the image.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention is shown in FIGS.
FIG. 1 is a block diagram of a moving body guiding apparatus according to a first embodiment of the present invention. In FIG. 1, 12 is a marker attached along a moving route and showing the attribute of the route, 7 is a visual guidance camera mounted facing the traveling direction, 8 is a route recognition camera mounted vertically downward, Reference numeral 9 is an image processor for detecting and recognizing markers from the images obtained by the two cameras, 10 is a controller for determining the traveling direction of the moving body from the recognition result, and 16 is controlling the traveling direction of the moving body. A steering mechanism, 15 a drive mechanism for moving the moving body, 13 a moving distance measuring device for measuring the moving distance of the moving body, 14 a gyro for measuring the posture of the moving body, 11 a memory for storing the position of the marker as a map It is a vessel.

FIG. 2 shows an outline of the guiding method of the first embodiment. A marker 12 indicating a route is attached to the floor, and the marker is attached to the moving body 3
It is recognized by the camera 8 mounted on the. When the marker 12 is out of the field of view or lost, the dead reckoning (dead reckoning) by the gyro 14 and the moving distance measuring device 13 is performed.
ning: Position estimation).

Two visual guidance cameras 7 and a route recognition camera 8 are used for visual guidance. The marker 12 is detected by the visual guidance camera 7, and the marker 12 is moved straight so that the marker 12 is always at the left-right center of the screen. Next, the route recognition camera 8 captures an image of the marker 12 that is located directly below, and collates it with the template 17 registered in the storage device 11 as a part of the map to determine the next route. At this time, the gyro 14 and the moving distance measuring instrument 13 are calibrated from the position of the marker 12 on the screen.

Next, the guiding method of the first embodiment will be described in detail. (1) Installation of Camera As shown in FIG. 3, the visual guidance camera 7 is installed obliquely downward, and the route recognition camera 8 is installed vertically downward.

When the height of the visual guidance camera 7 is set to H1, the angle is set obliquely downward θ, and the angle of view is φ, the distance from the moving body 3 to d1 to d2 comes into the visual field.
Further, if the route recognition camera 8 is installed vertically downward at the height H2 and the angle of view is similarly φ, the d3 squares directly below the camera are in the field of view.

D1 = H1 · tan (θ−φ / 2) d2 = H1 · tan (θ + φ / 2) d3 = 2 · H2 · tan (φ / 2) (2) Marker installation As shown in FIG. The marker 12 turns right, turns left, goes straight,
It indicates attributes such as stop, cross, T-shape, etc., and is installed at each important point for controlling the trajectory of the moving body 3. If the distance between intersections is very long, install a straight ahead mark at an appropriate place between them.

The marker is made of a material such as a reflective tape that causes a large difference in brightness from the floor so that the marker can be easily extracted from the floor. All the positions and attributes of the respective markers 12 are stored in the storage device 11 as a map. (3) Description of Moving Route As shown in FIG.
It is described using the attribute and position of. (4) Initial installation of moving body As shown in FIG. 6, the moving body 3 is placed at a position where the markers 12 are present at the left and right screen centers of the visual guidance camera image 18.
Is installed, and the zero points of the gyro 14 and the moving distance measuring device 13 are adjusted. (5) Visual Guidance As shown in FIG. 7, when the marker 12 is recognized by the visual guidance camera 7, the movement of the moving body is such that the marker 12 is always located at the left and right screen centers of the visual guidance camera image 18. To control. Thereby, the moving body 3 is moved to the marker 12
Go straight toward. (5A) Extraction of Marker As described in (2), the marker has higher brightness than the floor surface, and thus is separated from the floor surface by binarization.
The method is shown below. (A) As shown in FIG. 8, since the marker appears near the center of the upper portion of the visual guidance camera image 18 and has a higher brightness than the surrounding floor surface, the area having a high brightness in the vicinity is binarized. To extract. (B) As shown in FIG. 9, since the mounting height and angle of the camera are known, the size of the area within the field of view d × s
(M) is expressed by the following equation.

D = d2-d1 s = 2 · d2 · tan (φ / 2) If the size of the marker is m × m (m) and the number of pixels of the visual guidance camera image 18 is i × j pixels, The size of the marker on the image is expressed by the following equation.

R = (m / d) i, l = (m / s) j (pixel) (c) Since the size of the marker on the image is known as shown in (b), Of the areas extracted in (a), only the area of r × l pixels serves as a marker. The steering is controlled by using the center of gravity of the marker area and the deviation of the left and right image centers of the visual guidance camera image 18 from each other. After (d), the binarization process is similarly performed in the vicinity of the first extracted marker region to trace the marker region. (5B) Steering Control As shown in FIG. 10, the displacement of the center of gravity of the marker 12 from the center of the left and right images of the visual guidance camera image 18 is σ, and the coordinates from the bottom of the image are ω. The distance d4 from the visual guidance camera 7 to the center of gravity of the marker 12 is given by the following equation.

D4 = d1 + d (ω / i) s1 is the horizontal visual field distance at the distance d4 from the visual guidance camera 7 by the following equation.

S1 = 2d4tan (φ / 2) The actual displacement amount Λ of the marker 12 with respect to the traveling direction of the moving body.
Is given by Λ = s1 · (σ / j) From the above, the inclination π of the moving body in the traveling direction with respect to the marker 12 is expressed by the following equation.

Inclination π = tan ⁻¹ (Λ / d4) Therefore, if the steering is turned by this angle, the moving body 3 will face the marker 12.

If an obstacle such as a human is present, the marker 12
If you lose sight, gyro 14 and moving distance measuring device 1
Perform dead reckoning (position estimation) by 3.

Since the position of the passed marker is known, the position and orientation of the moving body with respect to the marker are measured by dead recording. Since the position of the marker to be recognized next is already known from the map of the moving body 3, the direction of the marker to be recognized next with respect to the current position of the moving body is calculated. If the steering is controlled so that the moving direction of the moving body is directed in that direction, the moving body can move toward the next marker. (6) Recognition of Route When the moving body 3 moves and the marker 12 is captured by the route recognition camera 8 as shown in FIG. 11, the marker 12 is captured by the route recognition camera image 19 as in the visual guidance. The movement of the moving body 3 is controlled so as to come to the center of the left and right screens. When the marker 12 comes to the center of the route recognition camera image 19, the marker 12 is recognized and compared with the described route to determine the next route. (6A) Recognition of Marker The image processor 9 recognizes a marker from the image of the camera image 19 for path recognition. The marker recognition is performed by extracting the marker from the image of the route recognition camera image 19 and performing matching between the marker and the image of the marker registered in the storage device 11 as in (5) Marker extraction. recognize.

In this matching, as shown in FIG. 12, the edge of the extracted marker is detected, the inclination thereof is obtained, and the image of the marker registered in the storage unit 11 is rotated by that angle. This is done by taking the difference. (7) Calibration of gyro and movement distance measuring device In the route recognition camera image 19 obtained in the route recognition, the position and orientation of the moving body 3 is obtained from the displacement and inclination of the marker 12 from the screen center, and the movement of the gyro 14 and the gyro 14 are performed. The distance measuring device 13 is calibrated.

In the above (6), when the marker 12 comes into the screen from near the left and right screen centers of the route recognition camera image 19, the left and right shifts are corrected by the time the marker 12 is located at the center of the screen. It Therefore, the center of gravity of the marker 12 coincides with the center of the screen.

However, when the marker 12 appears from a position apart from the left and right screen centers of the route recognition camera image 19, the deviation cannot be corrected and the center of gravity of the marker 12 does not match the screen center.

Therefore, in the image processor 9 shown in FIG. 1, as shown in FIG. 13, the center of gravity 20 of the marker 12 is detected, the deviation from the center of the screen is obtained, and the position of the marker 12 which is previously held as a map is detected. Then, the position of the moving body 3 with respect to the marker 12 is detected using the deviation from the screen center.

Next, the vertical edge 21 of the marker 12 is detected, and the inclination of the edge is detected to detect the azimuth θ of the moving body 3. As a result, the position / orientation of the moving body with respect to the marker is measured.

With respect to this position / orientation, the position and orientation of the moving body based on the outputs of the gyro 14 and the movement distance measuring device 13 are calibrated. As a result, the zero drift of the gyro 14 is canceled, the accumulated error of the moving distance measuring device 13 is canceled, and the like. By performing the above processing, the moving body can autonomously move along the set route.

[0041]

Since the present invention is constructed as described above, it has the following effects. (1) According to the present invention, even when a route is changed, it suffices to remove the marker before the route change attached to the key point of the route to be changed and attach a new marker to the key point of the new route. The accuracy of the attachment position is not required. (2) Therefore, the route can be easily changed and the layout can be easily changed. (3) Furthermore, since the number of markers is not so large, the cost of reattaching a new marker to a new marker when it becomes dirty can be reduced, the facility cost can be significantly reduced, and the troublesome maintenance management can be reduced. . (4) Further, even if the marker is lost, the dead reckoning enables stable guidance and does not cause a sudden behavior change. Therefore, it is possible to reduce the risk to workers who are performing other work.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a guidance device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an outline of a guiding method of the first embodiment.

FIG. 3 is a diagram showing a position of a camera mounted on the moving body of the first embodiment.

FIG. 4 is an explanatory diagram of a marker attached along the route of the first embodiment.

FIG. 5 is an explanatory diagram of a movement route description of a moving body according to the first embodiment.

FIG. 6 is a diagram showing an initial position of a moving body according to the first embodiment.

FIG. 7 is an explanatory diagram of visual guidance by the camera of the first embodiment.

FIG. 8 is an explanatory diagram of a marker extraction method according to the first embodiment.

FIG. 9 is a diagram showing the size of a marker on the image of the first embodiment.

FIG. 10 is a diagram showing the inclination of the moving body with respect to the marker of the first embodiment.

FIG. 11 is a diagram showing a route recognition method according to the first embodiment.

FIG. 12 is an explanatory diagram of a marker recognition method according to the first embodiment.

FIG. 13 is an explanatory diagram of the detection of the center of gravity of the marker according to the first embodiment.

FIG. 14 is an explanatory diagram of a path setting method in a conventional optical tape guide method.

FIG. 15 is an explanatory diagram of a conventional optical tape guide method.

FIG. 16 is an explanatory diagram of a path setting method in a conventional optical laser guiding method.

FIG. 17 is an explanatory diagram of a conventional optical laser guiding method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Optical tape, 2 ... Camera, 3 ... Moving body, 4 ... Camera image, 5-1 ... Laser light, 5-2 ... Laser lighthouse, 6 ... Reflector, 7 ... Visual guidance camera, 8 ... Route recognition camera , 9 ... Image processor, 10 ... Controller, 11 ... Memory device, 12 ... Marker, 13 ... Moving distance measuring device, 14 ... Gyro, 15 ... Drive mechanism, 16 ... Steering mechanism, 17 ... Template, 18 ... Visual guidance Camera image, 19 ... camera image for path recognition, 20 ... centroid of marker, 21 ... vertical edge.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Noboru Ida 1-1-1 Wadasaki-cho, Hyogo-ku, Kobe-shi, Hyogo Prefecture Mitsubishi Heavy Industries Ltd. Kobe Shipyard

Claims (1)

[Claims] 1. A guiding device for guiding a moving body (3) along a predetermined route, (A) a marker (12) attached along the moving route, and (B) showing a route attribute. It is obtained by a visual guidance camera (7) mounted diagonally downward in a direction, (C) a route recognition camera (8) mounted vertically downward, and (D) the two cameras (7, 8). Image processor for recognizing markers from captured images (9)
(E) a controller (10) for determining the traveling direction of the moving body (3) from the recognition result, (F) a steering mechanism (16) for controlling the traveling direction of the moving body (3), and (G) ) A drive mechanism (15) for moving the moving body (3), and (H) a moving distance measuring device (1) for measuring the moving distance of the moving body (3).
3), (I) a gyro (14) that measures the posture of the moving body (3), and a memory (11) that stores the position of the (J) marker (12) as a map. The moving body (3) is controlled so as to move toward the marker (12) imaged by the guidance camera (7), and when the marker comes directly under the moving body, the marker for route recognition camera (8) is used. (1
2) Recognize 2) and move to the next route, and when the marker is not in the field of view of the camera due to obstacles etc., the gyro (14) and the movement distance measuring device (13) are used to perform autonomous movement by dead reckoning. A guide device for a moving body, which guides the moving body (3) along a set movement path by performing the movement.