JPH01274212A - Mobile vehicle guidance facility - Google Patents

Abstract

PURPOSE:To easily change a travel path by changing the selection information of automatic travel, and information for the number of detection of a guidance part. CONSTITUTION:A mobile vehicle A is provided with a pair, right and left, driving wheels 1L and 1R, and an idle wheel 2 of caster type, and is constituted in such a way that steering, etc., can be performed freely. And a grid shape frame body L is provided on the ceiling side of the travel path by forming a grid point at every setting interval in a longitudinal and a lateral directions. And slit light projectors 3 which project two beams of slit light B1 and B2 toward the ceiling, and image sensors 4 as an image pickup means which image-pick up the projecting part of the frame body L from a direction different from a projecting direction are mounted on both end parts of the front and the rear sides of a vehicle, respectively. In such a way, steering control is performed based on image pickup information so that the automatic travel can be performed along one of plural guidance parts being set along the progressing direction of the vehicle in guidance for travel of grid shape, and also, the discrimination of a position can be performed. As a result, it is possible to change the travel path based on the selection information of the guidance part.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a moving vehicle guiding facility for automatically driving a moving vehicle along a set route.

[Conventional technology]

In the above-mentioned type of moving vehicle guidance equipment, conventionally, one traveling guide is provided on the ground side along the traveling route of the moving vehicle, and address information etc. for indicating the position on the traveling route of the moving vehicle is provided. a steering control sensor for detecting deviation in the width direction of the vehicle body with respect to the traveling guide; a steering control means for controlling steering based on the detected information; A mark sensor for reading the control mark and a position determining means for determining the position of the moving vehicle on the travel route based on the detection information of the mark sensor are provided.

By the way, methods such as an optical guidance type in which a light reflective tape is attached along the traveling route and a magnetic induction type in which a magnetic tape is attached along the traveling route will be used as a traveling guide. For example, an optical type in which a bar code or the like is attached to the traveling route side of a moving vehicle, or a magnetic type in which a bar code or the like is attached to the traveling route side by combining the magnetic pole arrangement of a plurality of magnets, etc. are used.

[Problem to be solved by the invention]

In the above-mentioned conventional configuration, when changing the travel route of the moving vehicle, it was necessary to change the layout of the travel guide and the installation position of the control mark, making it troublesome to change the equipment.

The present invention has been made in view of the above-mentioned circumstances, and its first object is to enable the travel route of a mobile vehicle to be changed without changing the layout of the travel guide. A second object is to improve the control accuracy of steering control by utilizing the configuration for achieving the first object.

[Means to solve the problem]

A first characteristic configuration of the moving vehicle guiding equipment according to the present invention is that a grid-like running guide is provided on the ceiling side so as to form grid points at set intervals in each of the vertical and horizontal directions, and the running guide an imaging means for taking an image of the vehicle, and a steering control operation based on the imaging information of the imaging means so that the vehicle automatically travels along one of a plurality of guide portions along the traveling direction of the vehicle body in the traveling guide. direction control means, and detects the number of guide portions located in a direction intersecting the direction of travel of the vehicle as it travels, based on the imaging information of the imaging means, and controls the traveling of the moving vehicle based on the detected number. The present invention is characterized in that a position determining means for determining a position on the route is provided.

Further, the second characteristic configuration is as follows.

That is, two of the imaging means are provided at a set interval in the longitudinal direction of the vehicle body, and the steering control means, based on the imaging information of each of the two imaging means and the value of the set interval, The present invention is configured to detect the inclination of the vehicle body with respect to the length direction of the guide portion along the vehicle traveling direction, and to perform steering based on the value of the inclination so that the inclination approaches zero.

[For production]

In the first characteristic configuration, a grid-like traveling guide is provided on the ceiling side so as to form grid points at set intervals in each of the vertical and horizontal directions, and the moving vehicle side captures an image of the traveling guide. Based on the information, the steering is controlled so that the vehicle automatically travels along one of the plurality of guide sections along the direction of travel of the vehicle in the grid-like driving guide, and as the vehicle travels, By detecting the number of guide portions located in the direction that intersects the guide portions, the position of the moving vehicle on the travel route is determined.

Further, in the second characteristic configuration, two imaging means for imaging the traveling guide are provided at a set interval in the longitudinal direction of the vehicle body,
The inclination of the vehicle body with respect to the length direction of the guide portion along the direction of travel of the vehicle body is detected, and the steering control is performed so that the inclination approaches zero.

〔Effect of the invention〕

Therefore, according to the first characteristic configuration, selection information as to which one of the plurality of guide portions along the vehicle traveling direction in the grid-like traveling guide is to be automatically traveled along, and the vehicle traveling guide. By simply changing information on the number of detected guide portions located in a direction intersecting the direction, the travel route of the moving vehicle can be easily changed without changing the layout of the travel guide. In addition, since the position of the moving vehicle on the traveling route is determined based on the information on the number of guide parts located in the direction intersecting the direction of travel of the vehicle body, the positional information on the traveling route of the moving vehicle can be obtained as in the conventional method. There is no need to install control marks, etc. for this purpose, and the equipment configuration can be simplified.

Further, according to the second characteristic configuration, since the steering control is performed so that the inclination in the vehicle body traveling direction with respect to the guide portion for automatically traveling the mobile vehicle approaches zero, the followability to the traveling guide, that is, the steering Control accuracy can be improved.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in FIGS. 6 to 8, a moving vehicle (A) has a pair of left and right propulsion wheels (IL) and (IR), which are configured to be driven and stopped separately on the left and right sides, at the center of the vehicle in the longitudinal direction. A pair of left and right caster-type idle wheels (2) are provided at each of the front and rear ends of the vehicle body, 1, and the left and right propulsion wheels (LL).

By driving each of the propulsion wheels (IL) and (IR) so as to differentiate the rotational speeds of (IR),
It is configured to be able to freely steer and spin-turn.

Further, on the ceiling side of the travel route on which the mobile vehicle (A> travels), a lattice-shaped frame (L) is installed downward from the ceiling surface so as to form lattice points at set intervals in each of the vertical and horizontal directions. In other words, as will be described later, this lattice-shaped frame (L) is used as a traveling guide.

Two slit lights (
A slit light projector (3) that projects BI), (82) toward the ceiling, and both slit lights (81), (B2
) The frame body (L) from a direction different from the respective projection directions.
An image sensor (4) is attached as an imaging means for taking an image of the slit light projection location.

To explain the slit light projector (3), the two orthogonal slit lights (81) and (82) scan the laser light within a set angle range in directions perpendicular to each other. ). A guide portion (Ll) located in a direction in which the center of the imaging field of the image sensor (4) intersects the vehicle body traveling direction of the frame body (L), and a guide portion located in a direction along the vehicle body traveling direction. (L2), in a state in which the moving vehicle (A) is positioned so that it overlaps with the grid point where the two slit lights (e, ),
The intersection of (B2) points toward a location away from the grid point,
Moreover, the image is projected perpendicularly to the ceiling.

To explain the image sensor (4), its imaging field of view is tilted at a setting angle in each of the front, rear, left, and right directions with respect to the ceiling, and as shown in FIG. , the two image sensors (4) are located such that the centers of their imaging fields of view are spaced apart from each other by a set interval (P) in the longitudinal direction of the vehicle body, and the moving vehicle (A) has:
The two image sensors ( The reference line (Lo) connecting the centers of the imaging field of view in 4) in the longitudinal direction of the vehicle body is made to coincide with the center in the width direction of the guide portion (L2) along the vehicle traveling direction.

That is, since the frame body (L) is in a state of protruding downward from the ceiling surface, the both slit lights (81
), (82) when viewed from an oblique direction, the two slit beams (B, ), (B2) appear as shown in FIG.
Each of them appears to be interrupted at a location where they cross the frame (L).

As will be described in detail later, the two slit lights (Bl
), (B.) are interrupted (Ba), (e
In b), the position on the imaging plane of the portion (Bb) that appears interrupted by the guide portion (L2) located in the direction along the vehicle traveling direction, and the installation interval (P) of the image sensor (4) in the longitudinal direction of the vehicle body. ), the inclination (
θ) is detected and the steering is controlled so that the inclination (θ) approaches zero, and as the vehicle advances, the portion that appears to be interrupted by a guide portion (Ll) located in a direction intersecting the direction of travel of the vehicle. The position of the mobile vehicle (A) on the traveling route is determined based on the detected number of the vehicle (Ba).

In the following description, the guide portion (L,) in the direction that intersects with the vehicle traveling direction will be referred to as the first guide portion (Ll), and the guide portion (L,) along the vehicle traveling direction will be referred to as the second guide portion (Ll). L2), and the first guide portion (Ll)
The part (Ba) that appears interrupted by the second guide part (L) is called the first slit part (Ba).
The portion (Bb) that appears cut off by 2) is referred to as the second slit portion (Bb).

Next, a control configuration for automatically driving the mobile vehicle (A) along a set travel route will be described.

As shown in FIG. 1, the imaging information of the image sensors (4) at the front and rear of the vehicle body is processed to determine the positions of the first slit portion (Ba) and the second slit portion (Bb) on the imaging surface. A pair of image processing devices (5) that detect
, and based on the detection information of the pair of image processing devices (5), the mobile vehicle (A) is guided to the second guide portion (L2).
a steering control means (100) that performs steering control so that the vehicle automatically travels along
A control device (6) using a microcomputer is provided, which constitutes a position determining means (101) for determining the position on the travel route based on the number of guide portion combs (2).

In the figure, (Ml) and (+42) are running motors that drive the left and right pair of propulsion wheels (1 m) and (IR), respectively, and (7) is the running motor (Ml), Q+2).
(pE+), a drive device for separately driving each of the
(PH2) is the traveling motor (Ml), <M2)
An encoder is attached to each of the encoders, and the traveling speed and traveling distance can be detected based on the detected information.

Next, based on the positional information of the second slit portion (Bb) in both the front and rear of the vehicle body detected by the pair of image processing devices (5), the second guide portion (L2) is The configuration of the means for detecting the inclination (θ) will be explained.

Every time a set time elapses, a projected image of the slit light (B, ), (82) projected from the slit light projector (3) is captured by the two image sensors (4), and the image In the processing device (5), the first slit portion (B
The processes of detecting the positions of a) and the second slit portion (Bb) are simultaneously executed on each of the front and rear sides of the vehicle body.

To explain the process for determining the position of the first slit portion (Ba), as shown in FIG. The lowest straight line among the straight lines parallel to the ), and then scans the image information from left to right on the screen, and extracts the rightmost straight line from among the straight lines parallel to the Y-axis in the vehicle width direction, in the vehicle width direction. The second slit m (Bb) is extracted toward the second slit.

However, since the image sensor (4) captures the projected images of both the slit lights (Bl) and (82) from an oblique direction, the extracted slit portions (B
The positions of a) and (Bb) are the image sensor (4).
Since the far side of the imaging field of view is distorted so that the change in distance is smaller than the near side, it is difficult to attach the image sensor (4) to the frame during image processing. Based on information such as the sheath inclination and the focal length of the optical system, the coordinate position is corrected according to the extracted position. Although not described in detail, the image sensor (4) is equipped with an optical filter that transmits only the light corresponding to the wavelengths of the two slit lights (B, ) and (82>) in order to eliminate the influence of external light. We are prepared.

As shown in FIG. 4, the widthwise center position (
Based on the value of X,, Y, ), (X2.Y2) (7) and the value of Q(P) between the front and rear image sensors (4), the inclination is calculated from the following formula (i). (θ) is found.

To explain the configuration for detecting the number of the first slit portions (Ba), the number of the first slit portions (Ba) is detected based on the imaging information of the image sensor (4) attached to the front side of the vehicle body. The presence or absence of the first slit portion (Ba) is determined, and if the first slit portion (Ba) exists, the first slit portion (Ba) is determined by determining whether or not the length is within a preset setting range. This allows the user to judge whether or not it has been detected.

To explain further, as shown in FIG.
1) and because the direction of the moving vehicle (A) is tilted with respect to the second guide portion (L2), the slit light (B1) crosses the second guide portion (L2) obliquely. This will occur if the line crosses the line.

However, when the mobile vehicle (A) is tilted with respect to the second guide portion (L2), the slit light (B
1) is different between the second guide portion (L2) and the first guide portion (Ll), the length of the first slit portion (Ba) is different from that of the slit light (
B1) is significantly longer when it crosses said second guide portion (L2) than when it crosses said first guide portion (Ll).

Therefore, based on whether the length of the detected first slit portion (Ba) is within the set range, the detected first slit portion (Ba) corresponds to the first guide portion (). The system allows the user to determine whether or not it is intended to be used.

As described later, when the first slit portion (Ba) is detected, the number of detected slit portions (Ba) is counted after the start of travel, and the traveling route of the mobile vehicle (A) is determined based on the counted number. The upper position is determined.

Next, determination of the position of the mobile vehicle (A) on the traveling route will be explained.

As shown in FIG. 3, the traveling route of the mobile vehicle (A) is as follows:
In the drawing, after traveling a set distance to the left, the cars are set to continue in a direction that intersects 90 degrees downward.

In the figure, (ST) is a transfer station for the load carried by the moving vehicle (A), and although it will not be described in detail, while the moving vehicle (A) is stopped at this station (ST), the moving vehicle (A)
) will be input or transmitted to the control device (6).

After the start of travel, the number of the first slit portions (Ba) detected from the travel start point as the vehicle progresses is set to a set value (in this embodiment, it is set to 6).
For example, as the left and right propulsion wheels (IL
) and (IR) at the same speed to make a spin turn to the left with respect to the direction of travel, changing the direction of travel by 90 degrees. After that, the first slit)R (Ba
), or based on the number of the first slit portions (Ba) detected after changing the traveling direction, the current position of the moving vehicle (A) is determined, and Its current position, that is, the first slit portion (
When the detected number of Ba) reaches the number corresponding to the position of the station (ST), it is automatically stopped.

Therefore, it is possible to select which of the frame bodies (L) provided in a grid pattern on the ceiling side along which the vehicle will automatically travel, and also to select the first slit portion (L) detected as the vehicle moves forward.
By changing the setting of the number of vehicles (Ba), the moving vehicle (A
) can be freely set and changed.

Next, the operation of the control device (6) will be explained based on the flowchart shown in FIG.

First, it is determined whether the moving vehicle (A) is running or not, and if it is running, an image capture command is sent to each of the image processing devices (5) at set time intervals. After outputting, wait until image processing is complete.

As the image processing is completed, as described above, the positions of the second slit portions (Bb) on both the front and rear sides of the vehicle
X+, Yl), (X2. Y2) (7) Based on the values, determine the inclination (θ) with respect to the second guide portion ().

Next, it is determined whether the mobile vehicle (8) is tilted to the left or right with respect to the second guide portion (L2) based on the sign of the determined value of the tilt (θ). Incidentally, the inclination (θ) is set so that it takes a positive value when it is tilted to the left, and a negative value when it is tilted to the right.

Then, when the value of the slope (θ) is positive and when the value is negative, both the front and rear positions (X,,Y,)
, (X2.Y2) Based on the positive and negative cD value (7), determine the tilt state with respect to the second guide portion (L2),
Target steering angles (αθ), (βθ), and (θ) are set in three stages of magnitude in accordance with the determined tilt state. However, it is set so that α>1>β>0.

To explain, as shown in FIG. 5(A), even if the slope (θ) has the same value, the second slit portion
b) A state in which the moving vehicle (A) is located on the right side with respect to the second guide portion (L2) depending on the positive or negative values of the positions (x, y,) and (X2. (indicated by a solid line), a state in which the front and rear of the vehicle body intersect with the second guide portion (L2) (indicated by a broken line in the figure), and a state in which the vehicle body is located on the left side with respect to the second guide portion (L2) (indicated by a broken line in the figure). In the figure,
Three types of states (indicated by phantom lines) will occur.

And those three states are the positions (X,,Y,).

The state corresponds to the combination of positive and negative values of (X2.Y2). That is, the position (X,,Y,).

If both (X2.Y2) are positive, the mobile vehicle (A) is located on the right side with respect to the second guide portion (L2), and the position (x+, y+).

If only one of (X2.Y2) is positive, the front and rear of the vehicle body intersect with the second guide portion (L2), and the positions (X,, y,), (X2.
If both Y2) are negative, the position is on the left side with respect to the second guide portion (L2).

Although the explanation is omitted, even when the value of the inclination (θ) is negative, as shown in FIG. 5 (b), the second guide As for the deviation state for the portion (L2), the above-mentioned three states occur. And their deviation state is the position (X,, Yl),
(X2. Y2) (7) It can be determined from the combination of positive and negative values. However, the combination of positive and negative values is the slope (
The relationship is opposite when the value of θ) is positive.

That is, the inclination (θ
), and the process of setting a target steering angle based on the value of the inclination (θ) and steering the vehicle corresponds to the steering control means (100).

After the steering control process is executed, it is determined whether or not the first slit portion (Ba) is detected based on the imaging information of the image sensor (4) on the front side of the vehicle body. If so, count the number of detections.

Then, based on the counted number of detections, it is determined whether or not it is a turn point, and if it is a turn point, the vehicle is turned to change the running direction as described above.

If it is not a turn point, it is determined whether or not it is a stop point based on the counted number of detections, and if it is a stop point, the vehicle is stopped.

That is, the process of counting the number of detected first slit portions (Ba) and determining whether it is a turn point or not and whether it is a stop point based on the counted number is performed. , corresponds to the position determining means (101) for determining the current position of the mobile vehicle (A).

[Another example]

In the above embodiment, the traveling guide is formed by using the frame (L) attached to the ceiling, but for example, a light reflective tape with a set width may be attached in a grid pattern. .

However, if there is no step between the tape and the ceiling surface, the light reflectance of the light reflective tape and the light reflectance of the ceiling surface may be different, and an ITV camera or the like may be used as the imaging means. What is necessary is to have it take an image.

Further, in the above embodiment, imaging means are provided on both sides of the front and rear of the vehicle body to detect the tilt (θ) with respect to the guide portion (L2) along the vehicle traveling direction, and to bring the tilt (θ) close to zero. Although we have exemplified a case in which steering control is performed based only on information about the detected inclination (θ), for example, it is possible to provide only one imaging means, detect a deviation in the width direction of the vehicle body, and eliminate the deviation to zero. Steering control may be performed based on the detected amount of deviation, direction of deviation, etc. so as to approach the
The specific configuration of the steering control means (100) can be modified in various ways.

Further, in the above embodiment, a pair of left and right propulsion wheels (IL),
(IR) are separately provided so that they can be driven and stopped separately for steering, but for example, a steering wheel may be provided for steering, and the specific configuration of the moving vehicle (A) can be changed in various ways.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the mobile vehicle guidance equipment according to the present invention, in which Fig. 1 is a block diagram of the control configuration, Fig. 2 is a flowchart of control operation, Fig. 3 is a plan view of the traveling route, Fig. 4 and Fig. Figures 5 (a) and (o) are explanatory diagrams of inclination detection, Figure 6 is a schematic perspective view showing the relationship between the travel guide and the moving vehicle, Figure 7 is a side view of the same, and Figure 8 is a front view of the same. It is. (A)...Moving vehicle, (L)...Traveling guide, (Ll)...Guide portion along the direction intersecting the direction of vehicle movement, (L2)... ...Guide part along the direction of vehicle movement, (P) ...Setting distance,
(θ)...Tilt, (4)...Imaging means, (100)...Steering control means, (101).
...Position determination means.

Claims (1)

[Claims] 1. A lattice-shaped traveling guide (L) is provided on the ceiling side so as to form lattice points at set intervals in each of the vertical and horizontal directions, and the traveling guide (L) Based on the imaging means (4) to take an image and the imaging information of the imaging means (4),
Steering control means (100) that performs steering control so that the vehicle automatically travels along one of a plurality of guide portions (L_2) along the traveling direction of the vehicle body in the traveling guide (L).
Then, based on the imaging information of the imaging means (4), the number of guide parts (L_1) located in a direction intersecting the direction of travel of the vehicle body as the vehicle travels is detected, and the movement is performed based on the detected number. A moving vehicle guidance facility provided with a position determining means (101) for determining the position of a vehicle (A) on a travel route. 2. The imaging means (4) is arranged at set intervals (
Two steering control means (10
0) is the inclination of the vehicle body with respect to the length direction of the guide portion (L_2) along the vehicle traveling direction based on the imaging information of each of the two imaging means (4) and the value of the set interval (P). 2. The moving vehicle guidance equipment according to claim 1, wherein the moving vehicle guidance equipment is configured to detect the inclination (θ) and perform steering based on the value of the inclination (θ) so that the inclination (θ) approaches zero.