JPH06348336A - Guide controller for automated guided vehicle - Google Patents

Abstract

PURPOSE:To drive an automated guided vehicle along a prescribed guiding route despits a dirty floor. CONSTITUTION:A guide controller is provided with a guide groove 30 formed along a guide route and at the side of a floor F, the projectors 16 which are set at both sides of an automated guided vehicle 10 and irradiate the light in the width direction of the vehicle 10, a photodetector array 18 which detects the intensity distribution of light reflected irregularly on the floor F by the light of the projector 16, a positional relation recognizing means which recognizes the relative positional relation between the vehicle 10 and the groove 30 based on the intensity distribution of the irregularly reflected light that is detected by the array 18, and a control unit which dtives the vehicle 10 along the groove 30 and based on the positional relation recognized by the positional relation recognizing means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling a guided vehicle.

[0002]

2. Description of the Related Art Conventionally, as guidance devices for automated guided vehicles,
What is disclosed in the microfilm of Japanese Utility Model Application No. 59-60889 (Japanese Utility Model Application No. 60-184108) is known. In this device, a guide line is laid by applying a white reflective tape or applying a white paint on the floor surface (other than the white system). On the other hand, the automatic guided vehicle (self-propelled carriage) is provided with a light projector that irradiates the floor surface with light, and a light receiving element that receives diffused reflected light from the floor surface side. Then, by utilizing the fact that the intensity of diffusely reflected light from the guideline is stronger than the intensity of diffusely reflected light from the floor surface (a part other than the guideline), the position of the guideline is detected, and the automated guided vehicle follows the guideline. It is designed to run.

[0003]

However, in this device, when the floor surface and the guideline (particularly the guideline) are contaminated due to long-term use or the like, the intensity of the diffused reflection light from the floor surface and the diffused reflection light from the guideline are used. Therefore, it becomes difficult to accurately detect the position of the guideline, and it becomes difficult to drive the automatic guided vehicle along the guideline (guide route).

Therefore, an object of the present invention is to provide a guidance control device for an automatic guided vehicle which can be driven along a predetermined guidance route even when the floor is dirty.

[0005]

In order to solve this problem, a guidance control device for an automatic guided vehicle according to the present invention provides a guidance provided on the floor side along a guidance route for traveling the automatic guided vehicle. A groove, a floodlight provided on the unmanned guided vehicle side to irradiate the floor side with light in the width direction of the unmanned guided vehicle, and a floodlight provided on the unmanned guided vehicle side and illuminated to the floor side by the floodlight A light receiving device that detects the intensity distribution of diffused reflected light from the floor side due to light in the width direction of the unmanned guided vehicle, and the guide groove and the unmanned guided vehicle based on the diffused reflected light intensity distribution detected by the light receiving device. A positional relationship recognizing means for recognizing the relative positional relationship of the unmanned vehicle and a control device for causing the automatic guided vehicle to travel along the guide groove based on the relative positional relationship recognized by the positional relationship recognizing means. Features and That.

[0006]

In the present invention, the light projector irradiates the floor side with light in the width direction of the automatic guided vehicle, and the light receiving device detects the intensity distribution of diffused reflected light from the floor side in the width direction of the automatic guided vehicle. To do. Then, by utilizing the fact that the intensity of diffusely reflected light from the guide groove is smaller than the intensity of diffusely reflected light from the floor surface (portion other than the guide groove), the positional relationship recognizing means
The relative positional relationship between the automatic guided vehicle and the guide groove is recognized.
Then, the control device causes the relative positional relationship between the automatic guided vehicle and the guide groove to become a predetermined one, so that the automatic guided vehicle is guided to travel along the guide groove. Then, at that time, even if the floor is dirty, the relationship that the intensity of diffused reflection light from the guide groove is smaller than the intensity of diffused reflection light from the floor surface (portion other than the guide groove) is maintained,
Does not cause malfunction.

[0007]

【Example】

<First Embodiment> Next, a first embodiment of the present invention will be described with reference to FIGS.
It will be described based on. As shown in FIG. 1, in this guidance control device for an unmanned guided vehicle, a guiding groove 30 is formed in a floor F along a guiding route for traveling the unmanned guided vehicle 10. The guide groove 30 has a rectangular cross section, and is formed at a position corresponding to the center line in the width direction of the automatic guided vehicle 10 when traveling along the guide route.

The automated guided vehicle 10 has four wheels 14 in a vehicle body 12, and a drive motor (not shown) provided in the vehicle body 12 drives wheels (the front side or the rear side of the four wheels 14 described above). Side two wheels) are driven, and steering motor 1
5 (see FIG. 2), the steered wheels (the above-mentioned four wheels 14
The front two wheels are steered.

Further, as shown in FIGS. 1 and 2, the automatic guided vehicle 10 includes a light projector 16, a light receiving array (light receiving device) 1
8, various circuits 24, 26, 28, and a control unit (control device) 20 are provided. The floodlight 16 is provided at the lower left front portion of the automated guided vehicle 10, and is located on the floor surface F.
A portion of S corresponding to almost all the portion in the width direction of the automated guided vehicle 10 is irradiated. The light receiving array 18 is provided over the entire width of the lower surface of the front portion of the automated guided vehicle 10, and includes nine photodiodes 22a.
~ 22i. Each photodiode 22a-2
At 2i, a current is generated according to the amount of irregularly reflected light received from the floor F side. The photodiodes 22a to 22i are connected to the control unit 20 via the scanning circuit 24. In addition, each photodiode 22a-22
i and the threshold value setting circuit 26 are connected to a comparator 28 (corresponding to the main part of the positional relationship recognizing means), and the comparator 28 is connected to the control unit 20.
The control unit 20 includes a CPU and an RO connected to the CPU.
It has an M and a RAM (both not shown), and RO
The program of the control content mentioned later is memorize | stored in M. Further, the RAM stores data and the like which is changed every moment when the program is executed. Control unit 20
The steering motor 15 is connected to the.

In this apparatus, the automatic guided vehicle 10 is guided to travel as follows. Light is emitted from the light projector 16 to the floor F side, and diffuse reflection light RL due to the light is received by the light receiving array 18. At this time, under the control of the control unit 20, each photodiode 22 is sequentially scanned from the left side by the scanning circuit 24 to be activated one by one, and each photodiode 22a to 22i is sequentially operated from the left side (22a → 22b → … → 22h → 22
Diffuse reflected light RL (such as i) is received. And
Diffuse reflected light R in each of the photodiodes 22a to 22i
The current generated according to the amount of received light of L and the current from the threshold setting circuit 26 are compared by the comparator 28.

Here, in advance, the amount of light received by each of the photodiodes 22a to 22i when the automatic guided vehicle 10 is just on the guide route (that is, when the central photodiode 22e and the guide groove 30 are just corresponding). (Amount of current corresponding to the amount of received light) is experimentally obtained as shown in FIG. The actual distribution of the intensity of diffusely reflected light is shown by a broken line, and as a result, the amount of light received by each of the photodiodes 22a to 22i is shown by a solid line. That is, since the projector 16 irradiates light from the left side of the vehicle, the intensity of diffusely reflected light is high on the left side portion of the floor surface FS, and the amount of light received by the corresponding photodiode 22b or the like is high, and the photodiodes 22c → 22d. And it gets lower gradually toward the right side. The inside of the guide groove 30 is the projector 1
Since it is a shadow of the light from 6, the intensity of the diffused reflected light from the guide groove 30 is much smaller than the diffused reflected light from the floor surface FS, and the amount of light received by the photodiode 22e at the center sharply decreases. Then, on the floor surface FS on the right side thereof, the intensity of diffused reflection light is recovered and the amount of light received by the photodiode 22f is recovered, and the amount of light received is gradually reduced toward the photodiodes 22g → 22h → 22i. The threshold value is set as shown in the figure, and the amount of light received is equal to or less than the threshold value in the portion corresponding to the guide groove 30 (the photodiode 22e in the center) and the right end portions (photodiodes 22h and 22i).

Under the above background, the comparator 28
In, it is compared whether or not the amount of light received by each of the photodiodes 22a to 22i is larger than a threshold value. Then, the photodiodes 22a to 22i are sequentially scanned from the left side (22a → 22b →
22c → ...), it can be determined that there is the guiding groove 30 directly below the photodiode 22 when the threshold value is first lowered. In addition, since the scan is performed from the left side in order,
There is no malfunction in the place where the threshold value is below the middle right end. Then, the steering motor 15 and the like are controlled by the control unit 20 so that the guide groove 30 is always located directly below the center photodiode 22e, that is, the center photodiode 22e is located directly above the guide groove 30. Meanwhile, the traveling of the automated guided vehicle 10 is guided.

As described above, this device takes advantage of the fact that the intensity of diffused reflection light in the guide groove 30 provided on the floor F is smaller than that of the floor surface FS (the portion other than the guide groove 30). The automatic guided vehicle 10 along the guiding groove 30.
Is to induce. In this device, even if the floor F (the floor surface FS and the guide groove 30) is contaminated due to long-term use or the like, the intensity of diffusely reflected light from the floor F side (that is, the amount of light received by the light receiving array 18). However, the guide groove 30 and the floor surface FS other than the guide groove 30 are clearly distinguished by appropriately lowering the threshold value in the threshold value setting circuit 26 accordingly. You can Therefore, even if the floor F is dirty, the automatic guided vehicle 10 can be driven along the guide route.

<Second Embodiment> Next, a second embodiment of the present invention will be described based on FIGS. 1, 4 and 5 focusing on the differences from the first embodiment. This embodiment is an effective device when the guide groove 40 is branched as shown in FIG. In this device, a mark 42 having a well-known structure is attached on the floor surface FS before each branch point 41. In this mark 42, at each branch point 41, the automatic guided vehicle 10 should run along the guide groove 40L (FIG. 5) of the left branch road or the guide groove 40R of the right branch road.
It shows whether to run along (Fig. 5). on the other hand,
As shown in FIGS. 1 and 5, the automatic guided vehicle 10 is provided with projectors 16R and 16L which are symmetrically provided on the left and right sides and are connected to the control unit 20. A mark sensor 44 for recognizing the mark 42 is also connected to the control unit 20 and provided.

Then, this apparatus is controlled as follows. The automated guided vehicle 10 first irradiates the floor F side with the left projector 16L as in the case of the first embodiment,
The light receiving array 18 is sequentially scanned from the left side to the right side by the scanning device (photodiodes 22a → 2
2b → ... → 22h → 22i), each photodiode 22
The guide grooves 40 are recognized by receiving the irregular reflection light by a to 22i, and the guide grooves 40 are guided to run along the guide grooves 40. And before the branch point 41,
The mark sensor 44 recognizes the mark 42, and the automatic guided vehicle 1
Read whether 0 should run to the left or to the right.
When moving to the left side, the same control is performed as before, but when moving to the right side (when traveling along the guide groove 40R on the right side in FIG. 5), the irradiation from the left projector 16L to the right projector 16R is performed. And the scanning device scans the light receiving array 18 from the right side to the left side (photodiode 2).
2i → 22h → ... → 22b → 22a). That is, the operating state is reversed symmetrically from that until then. Then, the relationship between the photodiodes 22a to 22i and the amount of light received by the photodiodes 22a to 22i is also a state in which the contents of FIG. Therefore, when scanning the light receiving array 18 from the right side to the left side (photodiodes 22i → 22h → ...
22b → 22a), the right guiding groove 40R is located directly below the photodiode 22 that first becomes less than or equal to the threshold value. Utilizing this relationship, the branching guide groove 40R,
The unmanned guided vehicle 10 is guided to travel while being controlled so that the central photodiode 22e is located directly above the right guiding groove 40R of the 40L.

As described above, in this embodiment, when the guide route is branched, the mark 42 is used to recognize which of the left and right sides the vehicle should travel, and the irradiation of the projectors 16R and 16L is performed based on the recognition result. And light receiving array 18
By switching the scanning direction of, it is possible to guide the vehicle to travel in a predetermined direction.

<Third Embodiment> Next, the first and second embodiments
A third embodiment, which is a modification of the embodiment, will be described. In the first and second embodiments, the floor F is directly formed with the grooves to provide the guiding grooves 30 and 40. However, in the present embodiment, FIG.
As shown in, the guide groove tape 60 is attached to the floor surface FS. The guide groove tape 60 has a gentle chevron cross section, and slopes 62a and 62b are formed on both the left and right sides, the height of which decreases toward the respective end sides. And
A guide groove 64 having a rectangular cross section is formed in the center thereof. Then, the guide groove 64 of the guide groove tape 60 is controlled to run along the guide groove 64 in the same manner as described above.

As described above, in this embodiment, since the guide groove 64 can be provided by adhering the guide groove tape 60 without directly forming the groove on the floor F, the guide groove 64 can be easily provided. It will be possible. Also,
Even if the position of the guide groove 64 is to be changed, it can be easily changed by reattaching the guide groove tape 60. Further, since the left and right side portions of the guide groove tape 60 are sloped portions 62a and 62b, other vehicles can easily get over the guide groove tape 60 and cross it, so that other vehicles can travel. It does not get in the way.

[0019]

According to the present invention, by utilizing the fact that the intensity of diffused reflection light in the guide groove provided on the floor side is smaller than that on the floor surface, the relative positional relationship between the automatic guided vehicle and the guide groove is recognized,
It guides the automatic guided vehicle along the guide groove. With this device, even if the floor (floor surface and guide groove) becomes dirty due to long-term use, etc., the intensity of diffusely reflected light from the guide groove and floor surface is only reduced overall. The difference between the intensity of diffusely reflected light from the groove and the intensity of diffusely reflected light from the floor surface still exists clearly. Therefore, even if the floor is dirty, the floor surface and the guide groove can be clearly identified, and the guided vehicle can be driven along the guide route.

[Brief description of drawings]

FIG. 1 is a perspective view showing the entire first to third embodiments of the present invention.

FIG. 2 is a system diagram showing a configuration of a first exemplary embodiment of the present invention.

FIG. 3 is a graph showing the amount of irregularly reflected light received by each photodiode in the first embodiment of the present invention.

FIG. 4 is a plan view showing a guide groove and the like according to a second embodiment of the present invention.

FIG. 5 is a system diagram showing a configuration of a second exemplary embodiment of the present invention.

FIG. 6 is a sectional perspective view showing a guide groove tape according to a third embodiment of the present invention.

[Explanation of symbols]

 10 Automated guided vehicle 16, 16R, 16L Emitter 18 Light receiving array (light receiving device) 20 Control unit (control device) 28 Comparator (positional relationship recognizing means) 30, 40, 40R, 40L, 64 Induction groove

Claims (1)

[Claims] 1. A guide groove provided on a floor side along a guide route for traveling an automatic guided vehicle, and a guide groove provided on the side of the automatic guided vehicle in a width direction of the automatic guided vehicle with respect to the floor side. A light projector that irradiates light, and a light receiving device that is provided on the side of the automatic guided vehicle and that detects the intensity distribution in the width direction of the automatic guided vehicle of diffusely reflected light from the floor side caused by the light that is emitted to the floor side by the projector. A positional relationship recognizing means for recognizing the relative positional relationship between the guide groove and the automatic guided vehicle based on the irregular reflection light intensity distribution detected by the light receiving device, and the relative position recognizing means for recognizing the relative positional relationship. A guide control device for an automatic guided vehicle, comprising: a control device that causes the automatic guided vehicle to travel along the guide groove based on a positional relationship.