JP5388148B1 - Automated guided vehicle - Google Patents

Abstract

An automatic guided vehicle capable of stably traveling a vehicle along a guidance line regardless of the traveling direction.
An automatic guided vehicle 1A that travels in a first direction and a second direction orthogonal to the first direction along guide lines 2a and 2b laid on a road surface, and includes at least one steered wheel 5; Steering wheel turning means 6 for turning the steering wheel 5, imaging means 3 for imaging the area A including the guide lines 2a and 2b and generating image data of the area A, and a halation area in the image data. And an illumination turning mechanism 7 for turning the illumination means 4 in accordance with the turning angle of the steering wheel 5, and image data generated during the first direction travel and during the second direction travel. In any of the generated image data, the guide lines 2a and 2b do not overlap with the halation area.
[Selection] Figure 1

Description

  The present invention relates to an automatic guided vehicle that travels along a guidance line laid on a road surface.

  2. Description of the Related Art Conventionally, as an automated guided vehicle that travels along a guide line laid on a road surface, a vehicle including a guide line imaging device that optically images a guide line is known (see, for example, Patent Document 1). As shown in FIG. 3A, the guide line imaging apparatus captures an area including the guide line 2 (imaging area A) and generates image data P of the area, and an imaging area A on the road surface. Illuminating means 14 for illuminating an area including The illumination means 14 has a plurality of white LEDs arranged linearly in the vertical direction of the drawing.

In this automatic guided vehicle, in order to brightly illuminate the entire imaging region A (particularly, the boundary between the guide line 2 and the road surface), the illumination means 14 that emits strong light is used. However, when the illumination unit 14 that emits strong light is used, when the light reflected in the region W in the imaging region A that is close to the illumination unit 14 reaches the imaging unit 13, it is shown in FIG. Thus, in the image data P generated by the imaging means 13, the region W becomes the halation area _PW .

Here, the halation area P _W means that the imaging means 13 cannot recognize the difference in color (for example, the difference between the color of the guide line 2 and the color of the road surface). An area that becomes completely white.

The size of the halation area _PW varies depending on the performance of the imaging means 13 and the like. FIG. 3C is a diagram illustrating an example of the relationship between the color difference of light incident on the imaging unit 13 and the size of the halation area _PW . The difference in color of light incident on the imaging means 13 is the color of light reflected in the area of the guide line 2 in the vicinity of the boundary between the guide line 2 and the road surface (area corresponding to B ₁ in FIG. 3B). When the difference between the color of light reflected by the road surface in the region of the boundary vicinity (region corresponding to the B ₂ in FIG. 3 (B)). As shown in FIG. 3C, the imaging unit 13 cannot recognize the color difference when the color difference falls below the threshold value D. However, the imaging unit 13 ′ having higher performance than the imaging unit 13 is The difference in color can be recognized until the difference in color falls below the threshold value D ′. For this reason, the imaging unit 13 ′ has a smaller halation area than the imaging unit 13 (P _W ′ <P _W ).

In the image data P, when the halation area P _W overlaps the guide line 2 and at least a part of the guide line 2 is hidden, the control unit of the automatic guided vehicle performs steering provided at the four corners of the vehicle based on the image data P. The wheel steering angle cannot be changed appropriately, and it may be difficult to drive the vehicle along the guide line 2.

For this reason, as shown in FIG. 4, in the automatic guided vehicle 1B that moves back and forth along the guide line 2a, the image pickup means 13 is placed on the center line of the automatic guided vehicle 1B in the lateral direction of the vehicle (on the guide line 2a in FIG. 4). By arranging the illumination means 14 on the right side of the imaging means 13 in parallel with the center line, the road surface area _W to be the halation area P W and the guide line 2a are not overlapped.

JP-A-7-64632

However, in the conventional automatic guided vehicle 1B, even if the arrangement of the imaging means 13 and the illumination means 14 is selected so that the road surface area _W that becomes the halation area P W and the guide line 2a do not overlap when moving forward and backward, As shown in FIG. 5, when the vehicle is traversed along the guide line 2b orthogonal to the guide line 2a, the road surface area _W that becomes the halation area PW and the guide line 2b overlap. For this reason, in the automatic guided vehicle 1B, it may be difficult to stably move the vehicle along the guide line 2b.

Even if the arrangement of the imaging means 13 and the illumination means 14 is reselected so that the road surface area _W that becomes the halation area P _W and the guide line 2b do not overlap when traversing, The road surface area _W, which becomes the halation area P _W when traveling, overlaps with the guide line 2a, which may make it difficult to move the vehicle forward and backward stably along the guide line 2a.

  In addition, as described with reference to FIG. 3C, the above problem may be solved by using a high-performance imaging unit (for example, an imaging unit capable of recognizing a slight color difference). However, such an image pickup means increases the cost of the automatic guided vehicle.

  This invention is made | formed in view of the said situation, The place made into the subject is providing the automatic guided vehicle which can be made to drive | work a vehicle stably along a guidance line irrespective of a running direction. It is in.

  In order to solve the above problems, an automatic guided vehicle according to the present invention includes (1) an automatic guided vehicle that travels at least in a first direction and a second direction orthogonal to the first direction along a guide line laid on a road surface. A vehicle, at least one steered wheel, a steered wheel turning means for turning the steered wheel, an imaging means for imaging an area including a guide line and generating image data of the area, and a halation area in the image data An illumination unit that illuminates the region so as to generate, and an illumination turning mechanism that turns the illumination unit in accordance with the turning angle of the steered wheel, and that is generated during the first direction travel and generated during the second direction travel. In any of the obtained image data, the guide line and the halation area do not overlap.

  According to this configuration, the illumination turning mechanism that turns the illumination unit according to the turning angle of the steered wheel causes the image data generated during the first direction travel (for example, forward / backward travel) and the second direction travel (for example, traverse). In any of the generated image data, the guide line and the halation area are not overlapped, so that the vehicle can be stably driven along the guide line regardless of the traveling direction.

  In the automatic guided vehicle of (1) above, (2) when the illumination means is composed of the first illumination means and the second illumination means, the first illumination means and the second illumination means are symmetrical in plan view with the imaging means as the center. In both the image data generated when traveling in the first direction and the image data generated when traveling in the second direction, the guide line has a halation area by the first illumination means and a halation area by the second illumination means It is preferable to be sandwiched between.

According to this configuration, since the positional relationship between the halation area and the guide line in the image data is fixed regardless of the travel direction, the vehicle can be traveled stably along the guide line.

  In the automatic guided vehicle of the above (1) or (2), (3) the steering wheel turning means is at least one for turning the steering wheel and the rotation of the turning motor to the steering wheel. The illumination turning mechanism preferably includes a turning motor as a power source and turns the illumination means in synchronization with the steered wheels.

  According to this configuration, since the steering wheel and the illumination unit are simultaneously turned by one power source (turning motor), it is possible to suppress the increase in size and cost of the vehicle due to the turning of the illumination unit. it can.

  In the automatic guided vehicle of (3), for example, (4) the at least one gear includes a first gear that is provided on the steering shaft of the steering wheel and that rotates together with the steering wheel, and the illumination turning mechanism includes the illumination unit. A second gear having the same diameter as the first gear and a chain hung on the first gear and the second gear can be configured.

  ADVANTAGE OF THE INVENTION According to this invention, the automatic guided vehicle which can be made to drive | work a vehicle stably along a guidance line regardless of a running direction can be provided.

It is a fragmentary top view of the automatic guided vehicle concerning one embodiment of the present invention, and (A) is a figure at the time of forward and backward travel, and (B) is a figure at the time of traversing. It is the partial side view seen from the X direction shown to FIG. 1 (A). (A) is a front view of a conventional guide line imaging device, (B) is an example of image data generated by the guide line imaging device of (A), and (C) is a diagram showing the relationship between imaging means and halation areas. It is. It is a partial top view at the time of forward and backward advance of the conventional automatic guided vehicle. It is a partial top view at the time of traversing of the conventional automatic guided vehicle.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of an automatic guided vehicle according to the invention will be described with reference to the accompanying drawings.

  1A and 1B show an automatic guided vehicle 1A according to a first embodiment of the present invention. As shown in the figure, the automatic guided vehicle 1A moves forward and backward in a first direction along a guide line 2a laid on the road surface, and traverses in a second direction along a guide line 2b orthogonal to the guide line 2a. Is.

  The guide lines 2a and 2b are formed by applying a paint or attaching a colored adhesive tape. Further, the guide lines 2a and 2b are colored with a color such that a boundary line with the road surface clearly appears. For example, when the color of the road surface is an achromatic color such as white, gray, or black, the colors of the guide lines 2a and 2b are preferably chromatic colors such as red and yellow.

  The automatic guided vehicle 1A captures an imaging area 3 that captures an area (imaging area A) including the guide lines 2a and 2b and generates image data of the area, and an imaging area A so that a halation area is generated in the image data. A lighting unit 4 for illuminating; steering wheels 5 provided at four corners of the vehicle; steering wheel turning means 6 for turning the steering wheel 5; lighting turning mechanism 7 for turning the lighting unit 4 according to the turning angle of the steering wheel 5; The control unit 8 is provided.

  The imaging means 3 is composed of a color CCD camera or the like, and is disposed on the center line of the automatic guided vehicle 1A in the left-right direction. The imaging unit 3 images the imaging area A including the guide lines 2a and 2b at a frequency of 15 times / second, for example, and generates image data of the imaging area A. The generated image data is sent to the control unit 8.

  The illumination unit 4 includes first illumination means 4a and second illumination means 4b made of a plurality of white LEDs arranged in a straight line, and a bracket 4c for holding them.

  As shown in FIG. 2, the 1st illumination means 4a and the 2nd illumination means 4b are arrange | positioned symmetrically centering | focusing on the imaging means 3, and illuminate the imaging area A from a different direction. Of the road surface areas illuminated by the first illumination means 4a, the road surface area W1 relatively close to the first illumination means 4a is a halation area in the image data generated by the imaging means 3. Similarly, the road surface area W2 relatively close to the second illumination means 4b among the road surface areas illuminated by the second illumination means 4b is also a halation area in the image data. The positional relationship between the areas W1 and W2 and the guide lines 2a and 2b will be described later.

  The bracket 4 c is formed of a downward U-shaped plate-like member that is formed symmetrically with respect to the imaging unit 3 and that is separated from the imaging unit 3. The bracket 4c has a pivot shaft 7c of the illumination pivot mechanism 7 fixed to the upper plate, and a first illumination unit 4a and a second illumination unit 4b are attached to the lower ends of the opposing side plates, respectively. By rotating the turning shaft 7c, the first illumination means 4a and the second illumination means 4b are turned together with the bracket 4c, but the imaging means 3 is not turned.

  The steering wheel turning means 6 is fixed to the turning motor 6a for rotating the motor shaft under the control of the control unit 8, the motor gear 6b fixed to the motor shaft of the turning motor 6a, and the steering shaft of the steering wheel 5. And a first gear 6c that meshes with the motor gear 6b and turns.

  The illumination turning mechanism 7 is connected and fixed so that the second gear 7a having the same diameter as the first gear 6c, the chain 7b hung on the first gear 6c and the second gear 7a, and the second gear 7a and the bracket 4c can turn. And the swivel axis 7c. The lighting turning mechanism 7 transmits the rotation (power) of the turning motor 6a transmitted to the first gear 6c to the lighting unit 4 via the chain 7b, the second gear 7a, and the turning shaft 7c, so that the steering wheel 5, the lighting unit 4 can be turned by the same angle as the steering wheel 5. That is, when the steering wheel 5 turns 90 degrees, the lighting unit 4 also turns 90 degrees.

  The control unit 8 controls the turning motor 6a (the amount of rotation of the motor shaft) based on the image data generated by the imaging unit 3 to change the steering angle of each steered wheel 5. For example, when the image data generated by the imaging means 3 includes a traveling direction switching mark previously set on the road surface, the turning motor 6a rotates the motor shaft under the control of the control unit 8, and the motor gear By turning 6b and the first gear 6c, the steering angle of the steered wheels 5 changes by 90 degrees.

  Next, the positional relationship between the road surface areas W1 and W2 that are halation areas in the image data and the guide lines 2a and 2b will be described.

  In the automatic guided vehicle 1A according to the present embodiment, as shown in FIG. 1A, the arrangement of the imaging means 3 and the illumination unit 4 is arranged so that the areas W1, W2 and the guide line 2a do not overlap each other when moving forward and backward. Is selected. Specifically, in the automatic guided vehicle 1A, the shape of the bracket 4c, the attachment positions of the first illumination means 4a and the second illumination means 4b, etc. so that the guide line 2a is sandwiched between the area W1 and the area W2 when moving forward and backward. Is preset. As a result, in the automatic guided vehicle 1A, the guide line 2a and the halation area do not overlap in the image data generated during forward / backward travel, so that the vehicle can be moved forward and backward stably along the guide line 2a.

  Further, in the automatic guided vehicle 1A, when the traveling direction is switched from the forward / reverse direction to the transverse direction, the motor shaft of the turning motor 6a rotates under the control of the control unit 8, thereby turning the motor gear 6b and the first gear 6c. Then, the steering wheel 5 turns 90 degrees, and at the same time, the rotation (power) of the motor shaft is transmitted from the first gear 6c to the lighting unit 4 via the chain 7b, the second gear 7a and the turning shaft 7c. The lighting unit 4 also turns 90 degrees.

  Thereby, in the automatic guided vehicle 1A, as shown in FIG. 1B, the guide line 2b is sandwiched between the region W1 and the region W2 when traversing. In other words, in the automatic guided vehicle 1A, the guide line 2b and the halation area do not overlap in the image data generated when traversing. For this reason, in the automatic guided vehicle 1A, the vehicle can be stably moved along the guide line 2b.

  In the automatic guided vehicle 1A, when the traveling direction is switched from the transverse direction to the forward / reverse direction again, the illumination unit 4 turns 90 degrees simultaneously with the steering wheel 5 as described above, and the illumination unit 4 returns to the original position. As shown in FIG. 1A, the guide line 2a is sandwiched between the region W1 and the region W2.

  Therefore, according to the automated guided vehicle 1A according to the present embodiment, the vehicle is guided to the guide line regardless of the traveling direction without using high-performance imaging means (for example, imaging means capable of recognizing a slight color difference). It can be made to travel stably along 2a and 2b.

  Moreover, according to the automatic guided vehicle 1A according to the present embodiment, the steering wheel 5 and the lighting unit 4 are simultaneously turned by one power source (turning motor 6a), so that the lighting unit 4 can be turned. Therefore, the increase in size and cost of the vehicle can be suppressed.

  The preferred embodiment of the automatic guided vehicle 1A according to the present invention has been described above, but the present invention is not limited to the above embodiment.

  For example, in the above-described embodiment, the illumination turning mechanism 7 includes the second gear 7a, the chain 7b, and the turning shaft 7c. However, as long as the lighting unit 4 can turn in synchronization with the steering wheel 5, Any configuration can be adopted. For example, the lighting unit 4 may be configured to have a power source different from that of the turning motor 6a, and the rotation (power) of the turning motor 6a may be electrically transmitted to the lighting unit 4. The illumination unit 4 may be configured to turn.

  In the above-described embodiment, the vehicle is configured to be able to travel in the forward / backward direction and the transverse direction, but may be configured to be able to travel in all directions including an oblique direction. When traveling in all directions, the control unit 8 controls the turning motor 6a (the amount of rotation of the motor shaft) so that the guide line comes to a predetermined position in the image data, and the steering angle of the steered wheels 5 is controlled. To change.

  In the said embodiment, although the illumination unit 4 contains the 1st illumination means 4a and the 2nd illumination means 4b, it may contain only any one. Furthermore, the shape of the bracket 4c can be arbitrarily changed according to the shape of the vehicle, the installation position of the imaging means 3, and the like.

  In the above embodiment, the imaging unit 3 is a color CCD camera, and the first illumination unit 4a and the second illumination unit 4b are white LEDs, but these are all examples.

1A Automatic guided vehicle 2a, 2b Guide line 3 Imaging means 4 Illumination unit 4a First illumination means 4b Second illumination means 4c Bracket 5 Steering wheel 6 Steering wheel turning means 6a Turning motor 6b Motor gear 6c First gear 7 Illumination turning mechanism 7a Second gear 7b Chain 7c Rotating shaft 8 Control unit

Claims (4)

An automatic guided vehicle that travels in a first direction and a second direction orthogonal to the first direction along a guide line laid on a road surface,
At least one steering wheel;
Steering wheel turning means for turning the steering wheel;
Imaging means for imaging an area including the guide line and generating image data of the area;
Illuminating means for illuminating the area such that a halation area occurs in the image data;
An illumination turning mechanism for turning the illumination means according to the turning angle of the steering wheel;
With
The automatic guided vehicle characterized in that the guide line and the halation area do not overlap in any of the image data generated during the first direction travel and the image data generated during the second direction travel. The illumination means comprises a first illumination means and a second illumination means,
The first illumination means and the second illumination means are arranged symmetrically in plan view with the imaging means as a center,
In both the image data generated during the first direction travel and the image data generated during the second direction travel, the guide line includes a halation area formed by the first illumination unit and a halation area formed by the second illumination unit. The automatic guided vehicle according to claim 1, wherein the automatic guided vehicle is sandwiched between two. The steering wheel turning means includes a turning motor for turning the steering wheel, and at least one gear for transmitting the rotation of the turning motor to the steering wheel.
3. The automatic guided vehicle according to claim 1, wherein the lighting turning mechanism turns the lighting unit in synchronization with the steering wheel using the turning motor as a power source. 4. The at least one gear includes a first gear which is provided on a steering shaft of the steering wheel and turns with the steering wheel;
The illumination turning mechanism is
A second gear having the same diameter as the first gear, swiveling with the illumination means;
A chain hung on the first gear and the second gear;
The automatic guided vehicle according to claim 3, comprising:

Images