JPH0550004B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is used in transportation equipment such as logistics systems and factory automation, and when the unmanned trolley is run along a travel route, the unmanned trolley is given information on the destination. The present invention relates to a communication method for an unmanned trolley in which instructions for loading and unloading cargo are given through communication with the ground side.

[Background Art] Conventionally, in logistics systems and the like, a plurality of unmanned carts are driven along a travel route to transport cargo.

An unmanned trolley is a trolley that has a power source on it and is able to travel automatically.The equipment that allows such an unmanned trolley to run is currently used in peripheral equipment of automated warehouses, goods transport equipment in production lines,
It is widely used in conveyance equipment in automatic processing lines, and its feature is that it does not have dedicated rails. The fact that it does not have dedicated rails is advantageous in that it can run along the general paths of the factory, allowing it to use space shared with forklifts and people, and making it easy to change its running route.

Conventional unmanned trolleys do not have a computer mounted on the trolley side, and communication between the trolley and the ground station is performed by radio or guided radio to manage the traffic of the trolley.

However, due to the layout of the system, when multiple unmanned trolleys are introduced, control to prevent collisions and rear-end collisions is essential, so in addition to the communication means, control is also performed to prevent collisions between the trolleys. In this case, an expensive means was required separately from the collision prevention means.

Examples of conventional collision prevention control means include a closed section control method, a tracking control method, and a traffic control method.

The closed section control method divides the layout into several sections on the control surface, allows one unmanned trolley to run within one section, and the following vehicle receives a signal from the standby signal zone at the entrance of the section. This will cause the unit to wait and stop. In this tracking control method, each unmanned vehicle is tracked and managed by the ground station from its starting point to its destination point. or,
The traffic control method is an interactive control between the ground station side and the unmanned trolley, using serial signal transmission by guided radio as the interaction method, and dividing the layout into several sections, but does not require a passing detector. , a dialogue zone is set up at the entrance of the section, and the ground station needs to know where the dialogue zone is, so several dialogue zones are grouped into one group and the dialogue zones are scanned in groups. When an unmanned trolley enters the dialogue zone and sends information such as the machine number or destination to the ground station, collision avoidance is performed based on this information (``Measurement and Control'' Vol. 22) No. 11, 1982
[Problems to be solved by the invention] Conventionally, as mentioned above, collision prevention at intersections or merging points of unmanned trolleys has been implemented using control methods such as ~ by the control device installed on the ground side. Because
Expensive equipment such as radio or guidance radio was required as a means of communication between the unmanned trolley and the ground side.

The present invention provides an alarm transmitter/receiver for unmanned trolleys that is designed to prevent collisions between unmanned trolleys by directly communicating with each other without going through the ground-side control device, and is also used for communication with the ground-side control device. let, furthermore,
Requirements for a means of communication for unmanned trolleys: being inexpensive, being able to communicate even if the bogie stops accurately, and requiring communication at loading and unloading points, bogie waiting points, etc. The aim is to satisfy the following requirements, such as being able to select communication from the left, right, or center of the trolley depending on the environmental conditions at the location.

[Means for Solving the Problems] The unmanned trolley communication method of the present invention provides an unmanned trolley collision prevention system that prevents collisions of unmanned trolleys at intersections and merging points by direct communication between the trolleys. It also has a communication function with the ground side, and when the unmanned trolley reaches a certain point, a signal is sent by optical transmission from a predetermined transmitter to the ground side control device based on pre-stored travel route information, and the The purpose of this system is to send commands from the control device to the receiver of the trolley, and in accordance with these commands, instructions such as the destination of the trolley, unloading, loading, etc., are given. At least on the left, right, and center of the front end of a self-propelled cart, there is a device capable of communicating with a collision prevention transmitter/receiver of another cart, and transmitting instructions such as the next destination of the cart and instructions for loading and unloading cargo. In addition to installing an optical transmission type transmitter/receiver using infrared rays that can communicate with the communication transmitter/receiver of the ground side control device to be transmitted to the bogie, a code plate installed on the running surface is attached to the bogie. A running route sensor is installed on the bogie that can detect and identify information on merging points and intersection points, as well as information on communication positions with the ground side other than the merging points and intersection points, and further, on the bogie, the traveling route on which the bogie is traveling. A microcomputer that stores information such as the installation position of the ground-side control device at the communication position above, and a signal from the track sensor that gives an excitation command to the transmitter and a gate open command to the receiver; a collision prevention control circuit that outputs a signal to the microcomputer to stop the traveling drive of the receiving side bogie when the receiver receives a transmission signal from another bogie at a merging point or an intersection point; A transmitter/receiver selection circuit that selects a transmitter/receiver in the optimal direction for communicating with the ground-side control device using a selection signal from a microcomputer according to the installation position of the ground-side control device; A serial/parallel conversion circuit inputs a serial signal for command and converts this signal into a parallel signal, and stores the parallel signal converted by the serial/parallel conversion circuit until the command from the ground side control device is completed. A communication control circuit having a storage section that inputs a stored parallel signal to a microcomputer when the command is completed is incorporated, and when the bogie is running on its own, a track sensor used for collision prevention control is set to a communication position. When the code plate is detected at the location, the bogie is stopped, and the transmitter/receiver selection circuit selects the optimal direction for emitting signals according to the installation position of the ground-side control device at the communication location, according to the traveling route information stored in the microcomputer. The present invention is characterized in that a receiver is selected and communication is performed with the ground-side control device via the communication control circuit by optical transmission using infrared rays.

[Example] Hereinafter, an example of the communication method for an unmanned trolley of the present invention will be described with reference to the drawings.

FIG. 1 shows an outline of a device for implementing the communication method of the present invention, in which 1 is an unmanned trolley;
As shown in FIGS. 2 and 3, the vehicle is equipped with left and right travel drive wheels 3 in the center so as to be driven by independent travel drive motors 4 so as to be able to travel along a magnetic guide band 2, and The front and rear left and right driven wheels 5 are provided, and magnetic detection sensors 6 and 6' are attached to both front and rear ends of the trolley 1 as sensors for guiding the running of the trolley 1. By detecting the magnetic field of the belt 2, it is possible to automatically travel along the guide belt 2. This unmanned trolley 1 is made to memorize all the conditions of the traveling route, such as where the trolley 1 is traveling, whether there is an obstacle on the left, right, or front that prevents communication. Or on which side of the ground at which point the ground-side control device is located.
A microcomputer, a collision prevention control circuit, a communication control circuit, and a transmitter/receiver selection circuit are installed in the front end of the trolley 1, or both front and rear ends of the trolley 1. Transmitters 7 are attached at three locations so that transmission can be made in any direction, and receivers 8 are attached to the bottom of each of the transmitters 7, respectively.

The above-mentioned collision prevention control circuit allows direct communication between a bogie when it approaches a merging point or an intersection point with another bogie that is approaching the same merging point or intersection, and When the approaching bogie passes by while emitting a signal, and another bogie receives the signal, the bogie is instructed to wait without entering the confluence or intersection until the first bogie has passed through the confluence or intersection. The vehicle is kept stopped and controlled to prevent collisions, and a separate application is currently being filed for this collision prevention method. In this way, the collision prevention control circuit communicates with other trolleys on a first-come, first-served basis when an unmanned trolley approaches a merging point or intersection. a track sensor 9 that identifies information on merging points and crossing points; a transmitter that emits a signal to notify other bogies that they are passing through a merging point and crossing point; The cart is equipped with a receiver for checking the presence or absence of a passing cart, and the microcomputer issues an excitation command to the transmitter based on the signal from the track sensor 9.
In addition, a gate open command is issued to the receiver, and when the receiver receives a transmission signal from another bogie, the microcomputer controls the receiving bogie to stop running, and the first bogie that arrives at the junction or intersection is stopped. While the receiver of another truck receives the signal from the transmitter, the other truck is kept on standby without entering the merging point or intersection. In this embodiment, the running road sensor 9 in the collision prevention control circuit is used to detect a metal code plate 10 installed on the running surface at a communication position with the ground side other than merging points and intersection points. Track sensor 9
When it detects the communication position, it stops the bogie 1, and at the same time, the transmitter/receiver selection circuit selects the transmitter/receiver in the most suitable direction for communicating with the ground side control device based on the travel route information stored in the microcomputer. Then, a gate circuit is provided to give an excitation command to the selected transmitter 7 and a gate open command to the receiver 8, as in the case of collision prevention.

The communication control circuit causes the transmitter 7 to transmit optical transmission using infrared rays to the ground-side control device based on the data transmitted from the microcomputer, and causes the receiver 8 to receive command signals from the ground-side control device. Then, a serial/parallel conversion circuit converts the serial long/short wave signal using infrared rays into a parallel signal, and the parallel signal converted by the conversion circuit is stored until one command sent from the ground control device is completed. It has a storage unit that inputs the stored signals to the microcomputer all at once when one command is completed, and receives data input from the storage unit to the microcomputer to issue a destination command, an unloading command, and a loading command for the trolley 1. , etc. are displayed as commands.

The transmitter/receiver selection circuit selects the transmitter/receiver 7, 8 that is most suitable for communication at each point according to the conditions of the bogie traveling route which are stored in advance in the microcomputer. When one of the transmitter/receivers 7, 8 on the front, back, left, right, or center is selected, a command is input to the communication control circuit so that the signal from the communication control circuit is sent to the selected transmitter. It has a built-in decoding circuit.

On the other hand, on the ground side at each appropriate point on the running path of the bogie 1, the bogie 1
A ground-side control device 11 is installed at various places for communicating with the trolley, and the ground-side control device 11 is equipped with a transmitter 12 and a receiver 13, and receives signals sent from appropriate transmitters 7 of the bogie 1. When received by the transmitter 13, an operation command for the truck 1 is given to the truck 1 via the transmitter 12, so that communication with the truck 1 can be performed.

As described above, the communication method of the unmanned trolley in this embodiment is such that a microcomputer is mounted on the trolley 1 and the traveling route information of the trolley 1 is transmitted.
At a certain point on the travel path, the ground-side control device 11 is located on either side of the traveling direction, but at another point, on which side there is an obstacle, the transmitter/receiver 7, 8 that can communicate with the ground-side control device 11 is located. The microcomputer stores all information such as which direction should be used, where and at what point the ground side control device 11 is installed, etc. A running road sensor 9 in a collision prevention control circuit is installed in a truck 1 with a code board 10 installed along the running route near the installed point.
is designed to detect the code plate 10,
Communication for receiving commands from the ground side while the trolley 1 is running unmanned is performed as follows.

Until the travel path sensor 9 in the collision prevention control circuit detects the code plate 10 along the travel route, the travel drive control device of the bogie drives the travel drive motor 4 at a predetermined rotational speed using the microcomputer, so the bogie 1 is operated at a predetermined rotational speed. It runs on its own along a route stored in a computer.

Now, suppose that trolley 1 reaches point A.
The track sensor 9 detects the code board 10 installed on the ground at the location, and this detection signal is input to the microcomputer and a drive stop command is given to the drive control device of the drive motor 4, thereby causing the drive motor to stop. 4 stops and the trolley 1 stops, and at the same time, a command to open the gate is given to the receiver 8. The situation at point A has been input into the microcomputer as data in advance, so on which side is the ground control device 11 at point A?
If the trolley 1 stops at point A, the transmitter/receiver 7 and 8 to be used at point A will receive the A from the microcomputer.
It is selected by a selection signal at the point and an excitation command is given. That is, at point A, for example, if there are obstacles in front and in front of the left side, and the ground-side control device 11 is installed on the right side,
Of a total of six transmitter/receivers 7, 8 on the right and center, the transmitter/receiver 7, 8 on the right side at the front end is selected for communication.

As mentioned above, the transmitter/receiver selection circuit automatically selects the transmitter/receiver 7,
When 8 is selected, transmission data is sent from the microcomputer to the communication control circuit, and transmitted from the selected transmitter 7 to the ground-side control device 11. In this embodiment, infrared rays are used as the signal, and the signal is transmitted to the ground side by optical transmission. When the receiver 13 of the ground side control device 11 receives a signal from the transmitter 7 of the bogie 1, the ground side control device 11 receives a command from the bogie 1 side, and the bogie 1 of the ground side control device 11 performs the following command. Commands such as destination, unloading, loading, etc. are transmitted from the transmitter 12. When the receiver 8 of the bogie 1 receives a command such as the destination transmitted from the ground side, the signal is input to the communication control circuit. The signal from the ground side is a serial long/short wave using infrared rays, and the serial signal is converted into a parallel signal by the serial/parallel exchanger in the communication control circuit. Until one command is issued from the ground side, it is stored in the storage section of the communication control circuit, and once the one command is completed, it is input into the microcomputer all at once. Parallel signals input to the microcomputer give commands such as the next destination of the trolley, unloading or loading cargo on the trolley 1, and the trolley 1 receives this command from the ground side. Then move on to the next operation.

Next, when the trolley 1 goes to another point, for example, B, after the trolley 1 stops in the same way as above, the microcomputer controls the left, right, left,
Among the right and center transmitters 7, the transmitter 7 in the optimum direction is selectively excited, and at the same time the receiver 8 is also selected, the gate is opened, it enters the reception mode, and communicates with the ground-side control device 11.

Note that the transmitter/receiver 7 and 8 are also attached to the rear end of the truck 1 at three locations: left, right, and center.
This is because some vehicles travel not only forward but also in both directions, and when the trolley 1 is moved backwards at a certain point after moving forward along the travel route, the transmitter/receiver 7 and 8 at the rear end must be Selecting it by a selection signal and communicating with the ground side control device 11;
Furthermore, it is desirable that the optical transmission from each transmitter 7 reaches the receiver on the ground side reliably so that there is no leakage, and conversely, it is desirable that the commands from the ground side reach the receiver 8 on the bogie 1 without fail. Since it is desirable to
Of course, the receiver 8 may be set slightly downward, and the receiver 8 may be set slightly upward.

[Effects of the Invention] As described above, according to the communication method for unmanned trolleys of the present invention, the following excellent effects can be achieved.

(i) Transmitters and receivers attached to the bogies are used to communicate with the ground side in order to prevent collisions at merging points etc. between bogies, and the left, right, left, right, etc. Since any one of the transmitters and receivers in the central three directions is selectively used, there are no restrictions on orbit design.

(ii) Since the communication medium is infrared rays, which spread out, communication is possible without being affected by deviations in the stoppage of the trolley (front and back, left and right), and even if the output of the transmitter and receiver is relatively small, it is possible to communicate over a distance. You can communicate from any location.

(iii) Since optical transmission uses infrared rays, there is no need to process the ground side floor surface as in the case of conventional guided radio.

(iv) Also, since it is infrared, there is no risk of interference.

(v) Since the transmitter/receiver for preventing truck collisions is also used for communication, the installation space for the transmitter/receiver is small.

(vi) Cost reduction can be achieved from the above (iii), (v), etc.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a device implementing the unmanned trolley communication method of the present invention, FIG. 2 is a plan view of the trolley used in the method of the present invention, FIG. 3 is a side view of FIG. 2, and FIG. It is a schematic diagram showing an example of a trolley travel route. is a microcomputer, is a collision prevention control circuit, is a communication control device, is a transmitter/receiver selection circuit, 1 is an unmanned trolley, 3 is a travel drive wheel, 4 is a travel drive motor, 6 and 6' are magnetic detection sensors, and 7 is a A transmitter, 8 a receiver, 9 a track sensor, 11 a ground-side control device, 12 a transmitter, and 13 a receiver.

Claims (1)

[Scope of Claims] 1. A bogie equipped with a travel drive motor so as to be self-propelled is capable of communicating with a collision prevention transmitter/receiver of another bogie at least on the left, right, and center of the front end; In addition to installing an optical transmission type transmitter/receiver using infrared rays that can communicate with the communication transmitter/receiver of the ground-side control device to give the trolley the next destination of the trolley, commands for loading and unloading cargo, etc. , on the trolley,
The code board installed on the running surface is detected and the merging point is detected.
A track sensor is installed on the bogie that can identify the information on the intersection point and the communication position with the ground side other than the merging point and the intersection point; Based on the signals from the microcomputer, which stores information such as the installation position of the side control device, and the track sensor, it gives an excitation command to the transmitter and a gate open command to the receiver, and then sends an excitation command to the receiver at the confluence point or intersection point. a collision prevention control circuit that outputs a signal to the microcomputer to stop the traveling drive of the receiving bogie when the receiver receives a transmission signal from another bogie; and an installation position of the ground side control device at the communication position. A transmitter/receiver selection circuit that selects the transmitter/receiver in the optimal direction for communicating with the ground-side control device using a selection signal from the microcomputer according to the situation, and a serial signal for commands from the ground-side control device. A serial/parallel conversion circuit inputs the signal and converts the signal into a parallel signal, and stores the parallel signal converted by the serial/parallel conversion circuit until the command from the ground side control device is completed, and stores it once the command ends. and a communication control circuit having a storage section for inputting parallel signals to a microcomputer, and while the bogie is running on its own, a track sensor used for collision prevention control detects a code plate at a communication position. At this time, the bogie is stopped, and the transmitter/receiver selection circuit selects the transmitter/receiver in the optimal direction according to the installation position of the ground side control device at the communication position according to the traveling route information stored in the microcomputer, A communication method for an unmanned trolley, characterized in that communication is performed with a ground-side control device via the communication control circuit by optical transmission using infrared rays.