JP7698457B2 - Branch area entry/exit discrimination system, automated guided vehicle, and branch area entry/exit discrimination method - Google Patents

Description

The present invention relates to a branch area entry/exit determination system, an automated guided vehicle, and a branch area entry/exit determination method.

Conventionally, automated guided vehicles (AGVs) have been known that have a line tracing function that detects the magnetism of a magnetic tape laid on the floor and automatically travels along the route of the magnetic tape. For example, some of these automated guided vehicles have been put to practical use, and can be controlled to travel in a pre-specified direction on a branching road.

Here, in order to guide an AGV in the desired direction at a branching road, it is first necessary to make the AGV aware that it has entered a branching road. One method for making an AGV aware that it has entered a branching road is to install a magnetic marker to the side of the route and just before the branching road, and to have the AGV aware that it has entered a branching road by detecting the magnetism of the magnetic marker (see Patent Document 1).

JP 2019-204195 A

However, the technology disclosed in the above-mentioned Patent Document 1 has the problem that it cannot deal with cases where there is no space to install magnetic markers in appropriate positions, for example, due to a complex layout of the taxiway.

The present invention was made in consideration of the above problems, and aims to make it possible to detect when an automated guided vehicle has entered a branching path by using only a magnetic detection sensor for line tracing, without installing separate magnetic markers beside the guideway.

In order to solve the above problems, the branch area entrance/exit discrimination system of the present invention comprises:
An automated guided vehicle and a guideway for guiding the automated guided vehicle,
In the guideway in the branch area of the guideway, a first magnetic tape having a magnetic pole on one side is laid in a continuous state along the guideway for line tracing to guide the automatic guided vehicle;
In the guideway other than the branch area, a second magnetic tape having a magnetism of the other magnetic pole, which is a second magnetic tape for line tracing to guide the automatic guided vehicle, is laid in a continuous state along the guideway,
The automated guided vehicle is
a detection means for detecting magnetism from the first magnetic tape and the second magnetic tape;
A first derivation means for deriving a time change amount of the magnetism detected by the detection means;
a determination means for determining whether the host vehicle has entered or exited the branch area based on the amount of change over time of the magnetism derived by the first derivation means;
The present invention is characterized by the following:

According to this configuration, the unmanned guided vehicle detects magnetism from the first magnetic tape and the second magnetic tape while traveling on the taxiway, derives the amount of change in the detected magnetism over time, and determines whether the vehicle has entered or exited the branch area based on the derived amount of change in the magnetism over time. This makes it possible to grasp whether the unmanned guided vehicle has entered or exited the branch area without installing a separate magnetic marker on the side of the taxiway. In addition, by using the amount of change in the magnetism over time to determine whether the unmanned guided vehicle has entered or exited the branch area, the polarity change between the S pole and the N pole can be captured in the middle of the change, so that it is possible to determine whether the unmanned guided vehicle has entered or exited the branch area at a relatively earlier stage than in the method of determining whether the unmanned guided vehicle has entered or exited the branch area based on the amount of magnetism detected by the detection means. In addition, in the case of the above-mentioned method of determination based on the amount of magnetism, the amount of magnetism detected by the detection means fluctuates significantly even if the floor surface constituting the taxiway has even a slight unevenness, making it difficult to set a threshold value for determination and making it impossible to accurately determine whether the unmanned guided vehicle has entered or exited the branch area. However, in the case of the method of determination based on the amount of change in the magnetism over time, it is easier to set a threshold value for determination than in the method of determination based on the amount of magnetism, so it is possible to accurately determine whether the unmanned guided vehicle has entered or exited the branch area.

Also, preferably, the automated guided vehicle is
The detection means includes a plurality of magnetic detection sensors arranged in a direction perpendicular to the traveling direction of the vehicle,
a second deriving means for deriving an amount of deviation corresponding to each predetermined traveling direction pattern based on an amount of magnetism detected by each of the plurality of magnetic detection sensors and coordinate information corresponding to each arrangement of the plurality of magnetic detection sensors;
a travel direction control means for controlling a travel direction of the host vehicle based on a deviation amount corresponding to a predesignated travel direction pattern when the determination means determines that the host vehicle has entered the branch area;
It is advisable to prepare the following.
According to this configuration, it is possible to appropriately guide the automated guided vehicle in a desired traveling direction in the branching area without providing a separate detection means or magnetic marker for controlling the traveling direction of the automated guided vehicle.

Also, preferably, the automated guided vehicle is
A vehicle speed control means is provided for controlling a vehicle speed,
When the discrimination means determines that the vehicle has entered the branch area, the driving speed control means controls the driving speed of the vehicle to a predetermined speed that is slower than normal, and when the discrimination means determines that the vehicle has exited the branch area, the driving speed control means controls the driving speed of the vehicle to the normal speed.
According to this configuration, by controlling the traveling speed of the automated guided vehicle within the branching area to a predetermined speed that is slower than normal, it is possible to prevent the detection of magnetism by the detection means from being a false start when the vehicle's direction of travel is changed due to a branching, thereby more appropriately guiding the automated guided vehicle in the desired direction of travel in the branching area.

In addition, preferably, a plurality of types of second magnetic tapes having the magnetic pole of the other magnetic pole and different magnetic amounts are laid in the guideway other than the branching area,
The automated guided vehicle may preferably include an operation control means for performing an operation of a command corresponding to a predetermined threshold value when the magnetic quantity detected by the detection means exceeds the magnetic quantity of the second magnetic tape.
With this configuration, the automated guided vehicle can perform an operation corresponding to a desired command at a specified position where the magnetic quantity of the second magnetic tape changes, without the need to install a separate magnetic marker for commands next to the guideway.

In order to solve the above problems, the automated guided vehicle of the present invention comprises:
An automated guided vehicle that travels on a guideway in a branching area in which a first magnetic tape for line tracing having one magnetic pole is laid in a continuous state , and on a guideway other than the branching area in which a second magnetic tape for line tracing having the other magnetic pole is laid in a continuous state ,
a detection means for detecting magnetism from the first magnetic tape and the second magnetic tape;
A derivation means for deriving a time change amount of the magnetism detected by the detection means;
a discrimination means for discriminating whether the host vehicle has entered or exited the branch area based on the amount of change over time of the magnetism derived by the derivation means;
The present invention is characterized by the following:

In order to solve the above problems, the branch area entry/exit determination method of the present invention includes:
a detection step of detecting magnetism from the first magnetic tape and the second magnetic tape by a detection means for line tracing provided on an automated guided vehicle traveling on a guideway in a branching area on which a first magnetic tape for line tracing having magnetism of one magnetic pole is laid in a continuous state , and on a guideway other than the branching area on which a second magnetic tape for line tracing having magnetism of the other magnetic pole is laid in a continuous state;
a deriving step of deriving a time change amount of the magnetic field detected by the detection step;
a determination step of determining whether the automated guided vehicle has entered or exited the branch area based on the amount of change over time of the magnetism derived in the derivation step;
The present invention is characterized in that it includes:

According to the present invention, it is possible to detect when an automated guided vehicle enters a branching path by using only a magnetic detection sensor for line tracing, without installing separate magnetic markers beside the guideway.

1 is a schematic configuration diagram of a branch area entrance/exit discrimination system according to an embodiment of the present invention; FIG. 2 is an enlarged view of a first branch area shown in FIG. 1 . FIG. 2 is a block diagram showing the functional configuration of an automated guided vehicle. FIG. 4 is a front view showing an installation location of a sensor unit in an automated guided vehicle. 13 is a flowchart showing a control procedure for a branch area entrance/exit determination process. FIG. 11 is an explanatory diagram showing a method for determining whether or not a vehicle is entering or exiting a branch area. 4 is a flowchart showing a control procedure of a driving control process.

The following describes in detail an embodiment of the present invention with reference to the accompanying drawings. Note that the present invention is not limited to the illustrated examples.

[Configuration of the branch area entry/exit discrimination system]
First, the configuration of this embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic diagram of a branch area entrance/exit discrimination system 100 of this embodiment.

As shown in FIG. 1, the branch area entry/exit determination system 100 is configured with an automated guided vehicle 10 and a taxiway 20.

The automated guided vehicle 10 is, for example, an unmanned cart robot that transports luggage and the like in a factory or warehouse.

The taxiway 20 is a course for guiding the automated guided vehicle 10. The taxiway 20 is constructed by laying magnetic tape on the floor surface to form a desired course. As shown in FIG. 1, the taxiway 20 of this embodiment is provided with a first branching area A and a second branching area B where the taxiway 20 branches into two.

FIG. 2 is an enlarged view of the first branch area A shown in FIG.
2, the taxiway 20 in the first branching area A is composed of a first magnetic tape 20A having a magnetism of S pole. Although not shown, the taxiway 20 in the second branching area B is also composed of a first magnetic tape 20A having a magnetism of S pole.
On the other hand, the taxiway 20 other than the first branching area A and the second branching area B, i.e., the single-route taxiway 20 with no branching, is composed of a second magnetic tape 20B having a north pole magnetism.

[Configuration of the automated guided vehicle]
Next, the functional configuration of the automated guided vehicle 10 will be described with reference to Fig. 3. Fig. 3 is a block diagram showing the functional configuration of the automated guided vehicle 10.

As shown in FIG. 3, the automated guided vehicle 10 includes a control unit 11, a memory unit 12, an operation unit 13, a communication unit 14, a sensor unit 15, a drive unit 16, etc.

The control unit (first derivation means, discrimination means, second derivation means, travel direction control means, travel speed control means) 11 includes a CPU (Central Processing Unit) that executes various programs stored in the memory unit 12 to perform predetermined calculations and control each unit, and a memory that serves as a work area when the programs are executed (both not shown). The control unit 11 executes various processes in cooperation with the programs stored in the memory unit 12.

The storage unit 12 is composed of a non-volatile semiconductor memory, etc. The storage unit 12 stores system programs and application programs executed by the control unit 11, data required to execute these programs, etc.

The operation unit 13 has various function keys, accepts input by the user pressing each key, and outputs the operation information to the control unit 11.

The communication unit 14 wirelessly connects to a communication network and communicates with external devices connected to the communication network.

The sensor unit (detection means) 15 has multiple (e.g., six) magnetic detection sensors 151-156 that can detect the magnetic field emitted from the magnetic tapes (first magnetic tape 20A and second magnetic tape 20B) that make up the guideway 20, and outputs the magnetic flux density (magnetic detection amount) of the magnetic field detected by each of the magnetic detection sensors 151-156 to the control unit 11.

FIG. 4 is a front view showing the location of the sensor unit 15 on the automatic guided vehicle 10. As shown in FIG.
As shown in FIG. 4, the sensor unit 15 is provided at the front of the automated guided vehicle 10 (see FIG. 1) and at the bottom of the housing of the automated guided vehicle 10. The six magnetic detection sensors 151 to 156 described above are provided on the bottom surface of the sensor unit 15 so as to face the floor surface. These six magnetic detection sensors 151 to 156 are arranged at equal intervals in a row in a direction (X direction) perpendicular to the traveling direction of the automated guided vehicle 10 (Y direction (front direction of the paper) in FIG. 4). Note that the installation location of the sensor unit 15 and the arrangement of the magnetic detection sensors 151 to 156 are merely examples and can be appropriately changed depending on, for example, the width of the guideway 20. In addition, the number of magnetic detection sensors is not limited to six.

The memory unit 12 stores data on the position coordinates x1 to x6 (see FIG. 4) of the magnetic detection sensors 151 to 156 in the X direction, as well as the position coordinate xc (see FIG. 4) of the center position of the sensor unit 15 in the X direction. When the automated guided vehicle 10 is traveling, the control unit 11 performs travel control so that the difference between the center position xc of the sensor unit 15 in the X direction and the center position of the guideway 20 in the width direction is zero, that is, so that the center position xc of the sensor unit 15 in the X direction and the center position of the guideway 20 in the width direction coincide, and outputs instruction information related to the travel control to the drive unit 16.

The drive unit 16 controls the operation of the wheels, etc. based on command information related to driving control output from the control unit 11.

[Automated guided vehicle operation]
Next, the branch area entry/exit discrimination process of the automated guided vehicle 10 will be described with reference to FIG. 5 and FIG. 6. FIG. 5 is a flowchart showing the control procedure of the branch area entry/exit discrimination process. This branch area entry/exit discrimination process is a process executed when the automated guided vehicle 10 is traveling on the guideway 20. FIG. 6 is an explanatory diagram showing a method of discriminating entry/exit to a branch area. More specifically, the upper part of FIG. 6 is a diagram showing each progress process (state 1 to state 4) when the automated guided vehicle 10 progresses through the first branch area A in the direction of the arrow in the figure. The graph in the middle part of FIG. 6 is a graph showing the magnetic flux density (magnetic detection amount) detected by the magnetic detection sensor (third magnetic detection sensor) 153 at the position coordinate x3 and the magnetic detection sensor (fourth magnetic detection sensor) 154 at the position coordinate x4 shown in FIG. 4 over time in correspondence with the progress process of the automated guided vehicle 10. The lower graph in FIG. 6 is a graph showing the amount of change over time in the magnetic flux density shown in the middle graph (the amount of change in magnetic flux density per unit time) over time.

As shown in FIG. 5, when the branch area entry/exit determination process is started, the control unit 11 of the automated guided vehicle 10 first sequentially acquires the magnetic flux density (magnetic detection amount) detected by the third magnetic detection sensor 153 and the fourth magnetic detection sensor 154 (step S1).

Next, the control unit 11 derives the amount of change in magnetic flux density per unit time (time change [G/s]) based on the magnetic flux density sequentially acquired in step S1 (step S2).

Next, the control unit 11 determines whether the change in magnetic flux density per unit time (time change [G/s]) derived in step S2 is equal to or less than a first threshold (step S3). Here, the first threshold is a negative value that is smaller than the normal time when the time change is 0.

If it is determined in step S3 that the change in magnetic flux density per unit time (time change [G/s]) derived in step S2 is not equal to or less than the first threshold value (step S3; NO), the control unit 11 skips the processing in step S4 and proceeds to the processing in step S5.

For example, as shown in the upper part of FIG. 6, in state 1, that is, when the sensor unit 15 of the automated guided vehicle 10 is passing over the second magnetic tape 20B magnetized with a north pole, as shown in the graph in the middle part of FIG. 6, the magnetic flux density detected by the third magnetic detection sensor 153 and the fourth magnetic detection sensor 154 is approximately a constant positive value. Therefore, as shown in the graph in the lower part of FIG. 6, in state 1, the change in magnetic flux density per unit time (time change [G/s]) is approximately 0. As a result, in state 1, the control unit 11 determines that the magnetic flux density is not equal to or less than the first threshold value, and does not determine that the vehicle has entered a branch area (for example, the first branch area A).

In addition, in step S3, if it is determined that the amount of change in magnetic flux density per unit time (time change [G/s]) derived in step S2 is equal to or less than the first threshold value (step S3; YES), the control unit 11 determines that the vehicle has entered the branch area, i.e., that it has started entering the branch area (step S4).

For example, as shown in the upper part of FIG. 6, in state 2, that is, when the sensor unit 15 of the automated guided vehicle 10 passes over the boundary between the second magnetic tape 20B having a magnetized N pole and the first magnetic tape 20A having a magnetized S pole, as shown in the graph in the middle part of FIG. 6, the magnetic flux density detected by the third magnetic detection sensor 153 and the fourth magnetic detection sensor 154 gradually decreases from the positive constant value described above. Therefore, as shown in the graph in the lower part of FIG. 6, in state 2, the change in magnetic flux density per unit time (time change [G/s]) becomes a negative value smaller than the first threshold value. As a result, in state 2, the control unit 11 determines that it is equal to or less than the first threshold value, and determines that the branch area (for example, the first branch area A) has been entered.

Next, the control unit 11 determines whether the change in magnetic flux density per unit time (time change [G/s]) derived in step S2 is equal to or greater than a second threshold (step S5). Here, the second threshold is a positive value that is greater than the normal time when the time change is 0.

If it is determined in step S5 that the change in magnetic flux density per unit time (time change [G/s]) derived in step S2 is not equal to or greater than the second threshold (step S5; NO), the control unit 11 returns the process to step S1 and repeats the subsequent processes.

For example, as shown in the upper part of FIG. 6, in state 3, that is, when the sensor unit 15 of the automated guided vehicle 10 is passing over the first magnetic tape 20A magnetized with a south pole, as shown in the graph in the middle part of FIG. 6, the magnetic flux density of the magnetism detected by the third magnetic detection sensor 153 and the fourth magnetic detection sensor 154 is approximately a constant negative value. Therefore, as shown in the graph in the lower part of FIG. 6, in state 3, the change in magnetic flux density per unit time (time change [G/s]) is approximately 0. As a result, in state 3, the control unit 11 determines that it is not equal to or greater than the second threshold, and does not determine that the vehicle has exited the branch area (e.g., the first branch area A).

In addition, in step S5, if it is determined that the amount of change in magnetic flux density per unit time (time change [G/s]) derived in step S2 is equal to or greater than the second threshold value (step S5; YES), the control unit 11 determines that the vehicle has exited the branching area, i.e., that it has finished entering the branching area (step S6). After performing the process of step S6, the control unit 11 returns the process to step S1 and repeats the subsequent processes.

For example, as shown in the upper part of FIG. 6, in state 4, that is, when the sensor unit 15 of the automated guided vehicle 10 passes over the boundary between the first magnetic tape 20A having a magnetized S pole and the second magnetic tape 20B having a magnetized N pole, as shown in the graph in the middle part of FIG. 6, the magnetic flux density detected by the third magnetic detection sensor 153 and the fourth magnetic detection sensor 154 gradually increases from the negative constant value described above. Therefore, as shown in the graph in the lower part of FIG. 6, in state 4, the change in magnetic flux density per unit time (time change [G/s]) becomes a positive value greater than the second threshold value. As a result, in state 4, the control unit 11 determines that it is equal to or greater than the second threshold value, and determines that the vehicle has exited the branch area (for example, the first branch area A).

Next, the travel control process of the automatic guided vehicle 10 will be described with reference to FIG. 7. FIG. 7 is a flowchart showing the control procedure of the travel control process. This travel control process is a process executed when the automatic guided vehicle 10 is traveling on the guideway 20, similar to the branch area entrance/exit determination process described above. The control unit 11 of the automatic guided vehicle 10 is assumed to sequentially derive three types of deviation amounts e, eR, and eL of the following formulas (1) to (3) based on the magnetic flux densities (magnetic detection amounts) M1 to M6 detected by the magnetic detection sensors 151 to 156 at the position coordinates x1 to x6 shown in FIG. 4 and the position coordinates x1 to x6, while traveling on the guideway 20. Note that the following formulas (1) to (3) are merely examples and can be appropriately changed depending on, for example, the number of magnetic detection sensors installed.

As shown in FIG. 7, when the driving control process is started, the control unit 11 of the automated guided vehicle 10 first determines whether the guided path 20 on which the automated guided vehicle 10 is traveling is within a branch area (step S11).

If it is determined in step S11 that the taxiway 20 being traveled is not within a junction area, i.e., neither within the first junction area A nor within the second junction area B (step S11; NO), the control unit 11 performs travel control at the first speed, which is the normal speed, and based on the deviation amount e described above (step S12). Then, the control unit 11 returns the process to step S11 and repeats the subsequent processes.

In addition, if it is determined in step S11 that the taxiway 20 being traveled is within a branch area, i.e., within the first branch area A or the second branch area B (step S11; YES), the control unit 11 determines whether the pre-specified traveling direction is a straight line (step S13).

If it is determined in step S13 that the pre-specified traveling direction is going straight (step S13; YES), the control unit 11 performs driving control at a second speed slower than the first speed and based on the deviation amount e described above (step S14). However, in such a case (going straight in the branch area), it is assumed that the deviation amount e is derived by replacing M1 with M6 and M2 with M5 in the above formula (1). Then, the control unit 11 returns the process to step S11 and repeats the subsequent processes.

In addition, if it is determined in step S13 that the pre-specified traveling direction is not a straight line (step S13; NO), the control unit 11 determines whether the pre-specified traveling direction is a rightward direction (step S15).

If it is determined in step S15 that the pre-specified traveling direction is the right direction (step S15; YES), the control unit 11 performs driving control at a second speed that is slower than the first speed and based on the deviation amount eR described above (step S16). Then, the control unit 11 returns the process to step S11 and repeats the subsequent processes.

In addition, if it is determined in step S15 that the pre-specified traveling direction is not the right direction, i.e., that the pre-specified traveling direction is the left direction (step S15; NO), the control unit 11 performs driving control at a second speed that is slower than the first speed and based on the above-mentioned deviation amount eL (step S17). Then, the control unit 11 returns the process to step S11 and repeats the subsequent processes.

As described above, the branch area entry/exit determination system 100 of this embodiment includes an automated guided vehicle 10 and a guideway 20 that guides the automated guided vehicle 10. The guideway 20 in the branch areas (first branch area A and second branch area B) has a first magnetic tape 20A with a magnetic south pole (one magnetic pole) laid on it, and the guideway 20 in the areas other than the branch area has a second magnetic tape 20B with a magnetic north pole (the other magnetic pole) laid on it. The automated guided vehicle 10 detects magnetism from the first magnetic tape 20A and the second magnetic tape 20B with the sensor unit 15, derives the amount of change over time in the magnetism detected by the sensor unit 15 with the control unit 11, and determines whether the vehicle has entered or exited the branch area (first branch area A and second branch area B) based on the amount of change over time in the magnetism that has been derived.

As a result, while traveling on the taxiway 20, the automated guided vehicle 10 detects magnetism from the first magnetic tape 20A and the second magnetic tape 20B, derives the amount of change in the detected magnetism over time, and determines whether the vehicle has entered or exited the branch area based on the derived amount of change in the magnetism over time, so that it is possible to grasp whether the automated guided vehicle 10 has entered or exited the branch area without installing a separate magnetic marker beside the taxiway 20. In addition, by using the amount of change in the magnetism over time to determine whether the automated guided vehicle 10 has entered or exited the branch area, it is possible to capture the polarity change between the S pole and the N pole in the middle of the change, so that it is possible to determine whether the automated guided vehicle 10 has entered or exited the branch area at a relatively earlier stage than a method of determining whether the automated guided vehicle 10 has entered or exited the branch area based on the amount of magnetism detected by the sensor unit 15. Furthermore, in the case of the discrimination method based on the magnetic quantity described above, even slight unevenness on the floor surface that constitutes the guideway 20 causes the magnetic quantity detected by the sensor unit 15 to fluctuate significantly, making it difficult to set a discrimination threshold and making it impossible to accurately discern whether someone is entering or exiting the branch area. However, in the case of a discrimination method that uses the amount of change in magnetism over time, it is easier to set a discrimination threshold compared to a discrimination method based on magnetic quantity, making it possible to accurately discern whether someone is entering or exiting the branch area.

In addition, in the branch area entry/exit determination system 100 of this embodiment, the automated guided vehicle 10 has, as the sensor unit 15, a number of magnetic detection sensors 151-156 arranged in a direction perpendicular to the traveling direction of the vehicle, and the control unit 11 derives the deviation amounts e, eR, and eL corresponding to each predetermined traveling direction pattern based on the amount of magnetism detected by each of the magnetic detection sensors 151-156 and the coordinate information corresponding to each arrangement of the magnetic detection sensors 151-156, and when it is determined that the vehicle has entered the branch area, the traveling direction of the vehicle has been controlled based on the deviation amount corresponding to the previously specified traveling direction pattern.

Therefore, according to the branch area entry/exit determination system 100 of this embodiment, the automated guided vehicle 10 can be appropriately guided in the desired direction in the branch area without the need for a separate sensor unit or magnetic marker to control the direction of travel of the automated guided vehicle 10.

Furthermore, in the branch area entry/exit determination system 100 of this embodiment, the unmanned guided vehicle 10 controls the driving speed of the vehicle by the control unit 11, and when it is determined that the vehicle has entered the branch area, it controls the driving speed of the vehicle to a second speed that is slower than normal, and when it is determined that the vehicle has exited the branch area, it controls the driving speed of the vehicle to the normal first speed.
Therefore, according to the branch area entry/exit determination system 100 of this embodiment, by controlling the traveling speed of the unmanned guided vehicle 10 within the branch area to a second speed that is slower than normal, it is possible to prevent the magnetic detection by the sensor unit 15 from being a false start when the vehicle's direction of travel is changed due to a branch, and therefore it is possible to more appropriately guide the unmanned guided vehicle 10 in the desired direction of travel in the branch area.

The present invention has been specifically described above based on the embodiments, but the present invention is not limited to the above embodiments and can be modified without departing from the spirit of the invention.

For example, in the above embodiment, the induction path 20 in the first branch area A and the second branch area B is composed of the first magnetic tape 20A magnetized with the S pole, and the induction path 20 other than the first branch area A and the second branch area B is composed of the second magnetic tape 20B magnetized with the N pole. However, the induction path 20 in the first branch area A and the second branch area B may be composed of the second magnetic tape 20B magnetized with the N pole, and the induction path 20 other than the first branch area A and the second branch area B may be composed of the first magnetic tape 20A magnetized with the S pole.

In addition, in the above embodiment, for example, multiple types of second magnetic tapes 20B with different magnetic quantities are laid in the guideway 20 other than the branching area, and when the control unit 11 determines that the magnetic quantity detected by the sensor unit 15 exceeds a predetermined threshold corresponding to the magnetic quantity of the second magnetic tape 20B while the automated guided vehicle 10 is traveling on the guideway 20, the control unit 11 may control the automated guided vehicle 10 to perform the operation of a command corresponding to the threshold.

In addition, in the above embodiment, the communication unit 14 of the automated guided vehicle 10 is not limited to a configuration that wirelessly connects to a communication network and communicates with external devices connected to the communication network, but may be configured to perform short-range wireless communication with external devices using, for example, a Bluetooth (registered trademark) Low Energy (BLE) communication method, or may have each of the above configurations.

In addition to applying the above-mentioned branch area entry/exit discrimination system 100 to cases where an unmanned guided vehicle 10 is used to transport luggage or the like in a factory or warehouse, the branch area entry/exit discrimination system 100 may also be applied, for example, to cases where an unmanned robot equipped with a camera or the like is used to patrol and monitor a specified course.

100 Branch area entrance/exit discrimination system 10 Automatic guided vehicle 11 Control unit 12 Memory unit 13 Operation unit 14 Communication unit 15 Sensor units 151 to 156 Magnetic detection sensor 16 Driving unit 20 Guideway 20A First magnetic tape 20B Second magnetic tape A First branch area B Second branch area

Claims (6)

An automated guided vehicle and a guideway for guiding the automated guided vehicle,
In the guideway in the branch area of the guideway, a first magnetic tape having a magnetic pole on one side is laid in a continuous state along the guideway for line tracing to guide the automatic guided vehicle;
In the guideway other than the branch area, a second magnetic tape having a magnetism of the other magnetic pole, which is a second magnetic tape for line tracing to guide the automatic guided vehicle, is laid in a continuous state along the guideway,
The automated guided vehicle is
a detection means for detecting magnetism from the first magnetic tape and the second magnetic tape;
A first derivation means for deriving a time change amount of the magnetism detected by the detection means;
a determination means for determining whether the host vehicle has entered or exited the branch area based on the amount of change over time of the magnetism derived by the first derivation means;
A branch area entry/exit determination system comprising: The automated guided vehicle is
The detection means includes a plurality of magnetic detection sensors arranged in a direction perpendicular to the traveling direction of the vehicle,
a second deriving means for deriving a deviation amount corresponding to each predetermined traveling direction pattern based on a detection amount of magnetism detected by each of the plurality of magnetic detection sensors and coordinate information corresponding to each arrangement of the plurality of magnetic detection sensors;
a travel direction control means for controlling a travel direction of the host vehicle based on a deviation amount corresponding to a predesignated travel direction pattern when the determination means determines that the host vehicle has entered the branch area;
2. The branch area entrance/exit determination system according to claim 1, further comprising: The automated guided vehicle is
A vehicle speed control means is provided for controlling a vehicle speed,
the travel speed control means, when it is determined by the discrimination means that the host vehicle has entered the branch area, controls the travel speed of the host vehicle to a predetermined speed that is slower than normal, and, when it is determined that the host vehicle has exited the branch area, controls the travel speed of the host vehicle to the normal speed.
3. The branch area entrance/exit determination system according to claim 1 or 2. A plurality of types of second magnetic tapes having the magnetic pole of the other magnetic pole and different magnetic quantities are laid in the guideway other than the branching area,
the automatic guided vehicle further includes an operation control means for performing an operation of a command corresponding to a predetermined threshold value when the magnetic quantity detected by the detection means exceeds a predetermined threshold value corresponding to the magnetic quantity of the second magnetic tape,
4. The branch area entrance/exit discrimination system according to claim 1, An automated guided vehicle that travels on a guideway in a branching area in which a first magnetic tape for line tracing having one magnetic pole is laid in a continuous state , and on a guideway other than the branching area in which a second magnetic tape for line tracing having the other magnetic pole is laid in a continuous state ,
a detection means for detecting magnetism from the first magnetic tape and the second magnetic tape;
A derivation means for deriving a time change amount of the magnetism detected by the detection means;
a discrimination means for discriminating whether the host vehicle has entered or exited the branch area based on the amount of change over time of the magnetism derived by the derivation means;
An unmanned transport vehicle comprising: a detection step of detecting magnetism from the first magnetic tape and the second magnetic tape by a detection means for line tracing provided on an automated guided vehicle traveling on a guideway in a branching area on which a first magnetic tape for line tracing having magnetism of one magnetic pole is laid in a continuous state , and on a guideway other than the branching area on which a second magnetic tape for line tracing having magnetism of the other magnetic pole is laid in a continuous state;
a deriving step of deriving a time change amount of the magnetic field detected by the detection step;
a determination step of determining whether the automated guided vehicle has entered or exited the branch area based on the amount of change over time of the magnetism derived in the derivation step;
A method for determining whether or not a branch area is entered or exited, comprising:

Images