JPH0251709A - Control method for operation of unmanned carrier - Google Patents

Abstract

PURPOSE:To prevent the collision of plural unmanned carriers in case these carriers are set on the same driving course by using an obstacle detecting means, a carrier communication means, etc., so as to secure the communication among the carriers and to change the driving courses with each other. CONSTITUTION:A drive controller 10 of an unmanned carrier 1 always monitors the presence or absence of obstacles in the traveling direction of the carrier 1 via an obstacle sensor 12 while the carrier 1 is traveling on a prescribed course. When the presence of obstacles is decided, the carrier 1 performs the communication with an obstacle, i.e., another carrier 1 via a carrier communication equipment for the basis data on the priority set among the carriers 1 as well as the information on the sizes, the shapes, etc., of the carriers 1. Then the result of the communication are inputted to a drive information central processing part 34. When the part 34 judges that the driving courses should be changed, the carrier 1 having the lower priority is separated from the prescribed course so as not disturb the carrier having the higher priority. Thus the separated carrier 1 travels alone on a different driving course. Thus it is possible to prevent the collision of plural carriers 1.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is an unmanned system that supplies necessary jigs, parts, workpieces, etc. to work stations located at various locations in a factory while traveling between the work stations. Regarding guided vehicles, in particular, collisions between automated guided vehicles that can occur when multiple automated guided vehicles take the same travel route can be prevented by communicating between automated guided vehicles and changing the traveling route. The present invention relates to an automatic guided vehicle operation control method that can prevent such problems.

(Prior art) Due to recent demands for improved productivity and labor saving, for example, in production plants, work stations, which are fixed equipment located at various locations within the factory, are equipped with machines that carry out necessary maintenance while traveling between the work stations. Production lines using automatic guided vehicles that supply tools, parts, workpieces, etc. are becoming widespread.

There are various ways to control the operation of this automated guided vehicle, but for example, as shown in Japanese Patent Application Laid-open No. 60-77.208, guidance lines and marks for operation control are arranged on the route. However, there is a method that controls the operation status of the automatic guided vehicle, such as starting and stopping, by detecting the presence or absence of guide lines, marks, and obstacles in the direction of travel. 7 (A) and (B).

As shown in the figure, this automatic guided vehicle 1 has a mark detection sensor 3a that detects marks 2 arranged on a route connecting a plurality of work stations arranged at various locations in the factory.
~3d, and induction sensors 5a~5d for detecting the guidance line 4 provided along the route are provided at the front and rear thereof,
An obstacle detection sensor 12 for detecting the presence or absence of an obstacle in the traveling direction is disposed at the front of the vehicle in the traveling direction.

The automatic guided vehicle 1 also includes a battery 11 as a power source,
A drive motor 7a receives signals from the various sensors,
A drive control device 10 and a servo driver 9 are provided therein to control the drive of the drive motors 7a and 7b, and the drive motors 7a and 7b are started and stopped at one rotational speed based on signals from various sensors input to the drive control device 10. etc. are controlled. Note that the automatic guided vehicle 1 includes the drive motors 7a and 7b.
Left and right drive wheels 5a and 5b, which are driven independently, are provided approximately in the center thereof, and idle wheels 8a and ab are respectively attached to the front and rear center positions of the left and right drive wheels 5a and 5b. By giving a relative rotational difference to the left and right wheels 6a and 6b, the direction of movement can be freely changed.

(Problem to be Solved by the Invention) However, in such a conventional operation control method of an automatic guided vehicle, if an obstacle such as another automatic guided vehicle exists in the direction of travel, the obstacle detection The sensor 12 was supposed to detect this obstacle and stop the vehicle from moving, thereby avoiding a collision with the obstacle and ensuring safety. Therefore, the stopped automatic guided vehicle 1 is restarted. This means that the stoppage of one automatic guided vehicle causes the entire production line using multiple automatic guided vehicles to stop, and as a result, the work efficiency on the production line is reduced.・There were problems such as lowering.

The present invention has been made in view of such conventional problems, and is designed to prevent collisions between automatic guided vehicles that may occur when multiple automatic guided vehicles take the same travel route. The purpose of the present invention is to provide a method for controlling the operation of an automatic guided vehicle that can prevent accidents by communicating with the driver and changing the travel route.

(Means for Solving the Problems) To achieve the above object, the present invention detects obstacles by means of obstacle detection means installed in an automatic guided vehicle traveling along a travel route connecting a plurality of work stations. When the presence of an obstacle is detected, basic data communication such as mutual size, shape, priority, etc. is carried out with the obstacle, and the automatic guided vehicle travels according to the content of the communication. A method for controlling the operation of an automatic guided vehicle, characterized in that the route is changed to avoid a collision with the obstacle, and after the collision is avoided, the vehicle returns to the original traveling route.

(Function) If the above means is adopted, the automatic guided vehicle according to the present invention can communicate with the other automatic guided vehicle when the obstacle detection means detects the presence of an obstacle, for example, another automatic guided vehicle. Basic data communication such as the size, shape, and priority of the automatic guided vehicles is performed, and the travel route of the automatic guided vehicles is changed according to the communication content to avoid collisions between automatic guided vehicles, and after the collision is avoided, the original travel route is changed. It operates to return to. Therefore, collisions with obstacles can be avoided without stopping the operation of the automatic guided vehicle, and work efficiency on the production line can be significantly improved compared to the conventional technology.

(Example) Below, an example of the operation control method for an automatic guided vehicle according to the present invention will be described in detail based on the drawings.

FIGS. 1A and 1B show schematic configuration diagrams of an automatic guided vehicle according to the present invention. In addition, in the same figure, the seventh
The same members as those shown in the figures are given the same reference numerals.

As shown in FIG. 1, the automatic guided vehicle 1 is placed at various locations in the factory: on a route connecting multiple work stations where predetermined work is performed on the workpieces transported by the unmanned guided vehicle 11 and the guided vehicle 1. A mark detection sensor 3 that detects the arranged mark 2, a guidance sensor 5 that detects the guide line 4 provided along the route, and an obstacle detection sensor that detects the presence or absence of an obstacle. Various sensors 15a to 15d are arranged on each of the four sides of the outer surface of the automatic guided vehicle 1 that is perpendicular to the floor surface, and are connected to the various sensors 15, and drive height control controls the driving of the drive motors 7a to 7d. device 10
and a guided vehicle communication device 13 used for communication between a battery 11 that is the power source of the automated guided vehicle 1, and a central communication station 14 that issues instructions such as information regarding traveling to the automated guided vehicle 1. There are 52 digits inside it. The obstacle detection sensor 12 is a known photo sensor (not shown) consisting of a light emitting means such as a light emitting diode and a light receiving means such as a phototransistor that receives light from the light emitting means reflected at the obstacle. Consists of couplers.

Further, the drive motors 97a to 7 are provided at the four corners of the automatic guided vehicle 1.
Wheels 168 to 16d driven by d are arranged with their rotating shafts 17 sequentially shifted by 90 degrees. These wheels 168 to 16d transmit driving force in a direction perpendicular to the rotating shaft 17 when the drive motors 7a to 7d are driven, and unmanned conveyance in the direction of the rotating shaft 17 when the driving motors 7a to 7d are stopped. The car 1 is made movable. Note that the drive motor 7 and the wheels 16 constitute a drive wheel 18.

If we describe this drive wheel 18 in detail, Fig. 2 (8)
, (B), and the drive wheel 18 is connected to the output shaft 20 of the reducer 19 connected to the rotating shaft 17 of the drive motor 7.
The boss portion 21 is fixed to the
Three rollers 22a, 2 rotating in the direction of the output shaft 20
2b and 22c in the circumferential direction centered on the output shaft 20.
The wheels 16, which are arranged at intervals of 0 degrees, are connected to the output shaft 20.
The output shaft 2 is doubled in the direction, with the position of the roller 22 as a reference.
They are arranged 60 degrees apart from each other in the circumferential direction centering on 0.

The automatic guided vehicle 1 configured in this manner can freely change its traveling direction, straight forward movement, rotation, etc. depending on the number of drive motors 7 being driven.

Next, FIG. 3 shows a schematic configuration diagram of a drive control system fit10 for an automatic guided vehicle according to the present invention.

As shown in the figure, the drive control device 10 of the automatic guided vehicle 1 is an automatic guided vehicle that recognizes the current traveling position based on the detection signal of the mark detection sensor 3 that detects the mark 2 provided on the traveling route. a price recognition unit 30; a movement pattern storage unit 31 in which movement patterns of the automatic guided vehicle are stored;
A communication processing unit 32 that exchanges signals with other automatic guided vehicles 1 etc. via a guided vehicle communication device 13 and a work state detection sensor 24 that detects the placement state of a workpiece output an interlock signal according to the detection results. An interlock processing unit 33 that outputs information and also contributes to interlocking information from the communication processing unit 32, and pulse generators 26a to 26 that detect rotation-related information such as the rotational speed of the drive motors 7a to 7d.
A self-position storage unit 36 that stores the self-position by inputting and storing a pulse signal from d, information regarding the size, shape, etc. of other automatic guided vehicles 1, and information about other automatic guided vehicles and this automatic guided vehicle. A basic data storage unit 37 in which basic data such as priorities with respect to the car 1 is stored, and an obstacle detection sensor 1
2. Self-location recognition unit 30. Based on signals from the movement pattern storage section 31, interlock processing section 33, self-position storage section 36, and basic data storage section 37, whether or not to travel in a straight line or the speed of the automatic guided vehicle 1 is determined. car 1
Based on the detection signal from the guidance sensor 5, the signal from the driving information central processing section 34, and the pulse signals from the pulse generators 26a to 26d, the driving motors 7a to 7a calculate the driving state of the drive motors 7a to 26d. Servo drivers 25a to 25 that supply drive voltage to each of 7d.
d, and a servo control section 35 that outputs a drive signal.

The operation of the automatic guided vehicle configured in this way will be explained based on the flowchart shown in FIG. 4.

The automatic guided vehicle 1 has finished its work at a certain work station 23 and has been waiting until the next activation command is input.
When a start command and information regarding the travel route to the destination are input from the central communication station 14 via the guided vehicle communication 1a13 (steps 1 and 2), in response to this, the automatic guided vehicle 1 The vehicle starts traveling along the travel route (step 3).

While traveling along the predetermined travel route, the automatic guided vehicle 1 transmits the detection signal from the obstacle detection sensor 12 to the travel information central processing unit 3.
4, the vehicle constantly monitors the presence or absence of obstacles in the direction of travel (step 4), but if it is determined in step 4 that there are no obstacles, the process returns to step 3 and resumes the predetermined run. While continuing to travel along the route, if it is determined that an obstacle exists, the guided vehicle communication device 1
3, information regarding the size, shape, etc. of other automatic guided vehicles 1, and basic data such as priorities between other automatic guided vehicles 1 and this automatic guided vehicle 1 are communicated (step 5).
, this communication result is input to the driving information central processing unit 34 to determine whether or not to change the driving route (step 6).
.

As a result of the determination in step 6, if it is determined that the travel route should be changed, that is, if it is determined that the other automatic guided vehicle 1 has a higher priority, the travel information central processing unit 34: Referring to information regarding the size, shape, etc. of other automatic guided vehicles 1, the control section 35 is sent to the servo control unit 35 in order to change the traveling route of the present automatic guided vehicle 1 so as not to interfere with the traveling of other automatic guided vehicles 1. Information regarding the drive of the drive motor 7 is given, and as a result, the automatic guided vehicle 1 leaves the predetermined travel route and travels alone (step 7). On the other hand, if it is determined not to change the travel route, that is, if it is determined that this automatic guided vehicle 1 has a higher priority than the other automatic guided vehicle 1, the process returns to step 3 and the actual unmanned "Q guided vehicle" is determined. ] continues traveling along a predetermined travel route.

During the solo travel in step 7, the automatic guided vehicle 1:
While retracting to a position where it does not interfere with the travel of other automatic guided vehicles, it monitors whether or not the three unmanned guided vehicles 1 have passed (step 8).As a result of this monitoring, other automatic guided vehicles If it is determined that the automatic guided vehicle 1 has not passed, the automatic guided vehicle 1 continues to travel alone, while if it is determined that another automatic guided vehicle 1 has passed, the automatic guided vehicle 1 returns to the predetermined travel route again. Then, the process returns to step 3 and the vehicle travels along the predetermined travel route.

Note that a plurality of modes in which the automatic guided vehicle 1 changes its traveling route will be described with reference to the diagrams shown in FIGS. 5 and 6 for explaining the operation of the automatic guided vehicle.

First, as shown in FIGS. 5(a) and 5(b), in an example in which two automatic guided vehicles 1 approach each other from the front, the priority order is divided into cases where there is priority order and cases where there is no priority order. Specifically, when there is a priority order, the automatic guided vehicle 1 with the higher priority goes straight ahead, while the other automatic guided vehicles 1 retreat to a position where they do not interfere with the travel of the automatic guided vehicle 1 to avoid collision. However, if there is no priority order, collision is avoided by changing the travel routes of both automatic guided vehicles 1 to predetermined directions that do not interfere with each other's travel. Note that even in both of the above cases, when it is confirmed that the risk of collision has been avoided, the automatic guided vehicle 1 returns to its original traveling route.

Furthermore, as shown in FIGS. 6(a) and 6(b), in an example in which one automatic guided vehicle 1 approaches another automatic guided vehicle 1 from the rear, the priority order of the automatic guided vehicle 1 approaching from the rear is If we refer to cases where the priority is high and cases where it is not, if the priority of the automatic guided vehicle 1 approaching from behind is high, this automatic guided vehicle 1 will proceed straight, while the other automatic guided vehicle 1 in front will avoids a collision by temporarily retreating to a position that does not impede the movement of the automatic guided vehicle 1 until the automatic guided vehicle 1 passes; in contrast, in cases other than the above, the automatic guided vehicle approaching from behind 1 avoids a collision by temporarily changing its travel route and overtaking the preceding automated guided vehicle 1.

Note that even in both of the above cases, when it is confirmed that the risk of collision has been avoided, the automatic guided vehicle 1 returns to its original traveling route.

Finally, in both the case of approaching from the front and the case of approaching from the rear as described above, when changing the traveling route, it is necessary to check the size, shape, etc. of both two automatic guided vehicles 1. Information is exchanged, and the degree of change in the travel route is determined with reference to this information.

(Effects of the Invention) As explained in detail above, when the automatic guided vehicle according to the present invention detects the presence of an obstacle, for example, another automatic guided vehicle, by the obstacle detection means, the automatic guided vehicle according to the invention Basic data communication such as mutual size, shape, priority, etc. is carried out between the two, and the travel route of the automatic guided vehicles is changed according to the communication content to avoid collisions between automatic guided vehicles, and after the collision is avoided, the original Therefore, collisions with obstacles can be avoided without stopping the operation of the automatic guided vehicle, greatly improving work efficiency on the production line compared to conventional methods. This has a great practical effect in that it makes it possible to

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an automatic guided vehicle according to the present invention, FIG. 2 is a schematic configuration diagram showing drive wheels of the automatic guided vehicle, and FIG. 3 is a block diagram of a drive control device of the automatic guided vehicle. Figure 4 is a flowchart showing the operation of the automatic guided vehicle, Figures 5 and 6 are diagrams for explaining the operation of the automatic guided vehicle, and Figure 7 is a conventional unmanned guided vehicle. It is a schematic block diagram of a conveyance vehicle. 1... Automatic guided vehicle (obstacle), 12... Obstacle detection sensor (lI & harmful object detection means),
23...Work station.

Claims (1)

[Claims] Obstacle detection means installed on an automatic guided vehicle traveling along a travel route connecting multiple work stations detects the presence or absence of an obstacle, and when the presence of an obstacle is detected, it Basic data communication such as mutual size, shape, priority order, etc. is carried out between the two, and the travel route of the automatic guided vehicle is changed according to the content of the communication to avoid collision with the obstacle,
A method for controlling the operation of an automatic guided vehicle, characterized in that the automatic guided vehicle is configured to return to its original traveling route after avoiding the collision.