Branch area entry / exit discrimination system, automated guided vehicle, and branch area entry / exit discrimination method

Abstract

To enable entry of an automated guided vehicle into a branch path to be grasped without installing a magnetic marker separately beside a guide path and by using only a magnetic detection sensor for line trace.SOLUTION: A branch area exit / entry discrimination system 100 includes an automated guided vehicle 10 and guide paths 20 for guiding the automated guided vehicle 10. A first magnetic tape 20A magnetized with an S pole is laid on a guide path 20 for each of a first branch area A and a second branch area B, among the guide paths 20. A second magnetic tape 20B magnetized with an N pole is laid on guide paths 20 other than those for the first branch area A and the second branch area B. The automated guided vehicle 10 detects magnetism from each of the first magnetic tape 20A and the second magnetic tape 20B by means of a sensor unit 15, causes a control unit 11 to derive the amount of change in magnetism with time, detected by the sensor unit 15, and discriminates exit / entry of a self-vehicle from / into each of the first branch area A and the second branch area B, based on the derived amount of change in magnetism with time.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a branch area entry / exit discrimination system, an automated guided vehicle, and a branch area entry / exit discrimination method.

Background Art

[0002] Conventionally, an automated guided vehicle (AGV) having a line tracing function that automatically travels along a route of a magnetic tape by detecting the magnetism of the magnetic tape laid on the floor surface is known. In this automated guided vehicle, for example, those that can be controlled to travel in a predetermined direction at a branch are also in practical use.

[0003] Here, in order to guide the automated guided vehicle in a desired direction at a branch, first, it is necessary to make the vehicle itself recognize that it has entered the branch. As a method of making the automated guided vehicle recognize that it has entered the branch, for example, a technique is disclosed in which a magnetic marker is laid beside the route and immediately before the branch, and the automated guided vehicle is made to recognize that it has entered the branch by detecting the magnetism of this magnetic marker (see Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the technique disclosed in Patent Document 1 above has a problem that it cannot cope with a case where there is no space to install a magnetic marker at an appropriate position due to reasons such as a complicated layout of a guiding path.

[0006] The present invention has been made in view of the above problems, and aims to enable an automated guided vehicle to recognize that it has entered a branch road without separately installing a magnetic marker beside the guide path and by using only a magnetic detection sensor for line tracing.

Means for Solving the Problems

[0007] To solve the above problems, the branch area entry / exit determination system of the present invention includes an automated guided vehicle and a guide path for guiding the automated guided vehicle. In the guide path of the branch area, a first magnetic tape having magnetism of one magnetic pole, which is a first magnetic tape for line tracing for guiding the automated guided vehicle, is laid along the guide path. In a series of states laid In the guide path other than the branch area, a second magnetic tape having magnetism of the other magnetic pole, which is a second magnetic tape for line tracing for guiding the automated guided vehicle, is laid along the guide path. In a series of states laid The automated guided vehicle includes detection means for line tracing that detects magnetism from the first magnetic tape and the second magnetic tape, first derivation means for deriving a time change amount of the magnetism detected by the detection means, and determination means for determining entry / exit of the own vehicle into the branch area based on the time change amount of the magnetism derived by the first derivation means. It is characterized by comprising the above.

[0008] According to this configuration, when the automated guided vehicle is traveling on the guide path, it detects magnetism from the first magnetic tape and the second magnetic tape, derives the amount of change in the detected magnetism over time, and determines the entry and exit of the vehicle itself into and from the branch area based on the derived amount of change in the magnetism over time. Therefore, it is possible to grasp the entry and exit of the automated guided vehicle into the branch area without separately installing a magnetic marker beside the guide path. Also, when determining the entry and exit of the automated guided vehicle into the branch area, by using the amount of change in the magnetism over time, it is possible to capture the change in the polarity between the S pole and the N pole while it is in the process of changing. Thus, it is possible to determine the entry and exit into the branch area at a relatively earlier stage compared to the method of determining the entry and exit into the branch area based on the amount of magnetism detected by the detection means. Further, in the case of the determination method based on the above-mentioned amount of magnetism, even if the floor surface constituting the guide path has some irregularities, the amount of magnetism detected by the detection means fluctuates greatly, making it difficult to set the discrimination threshold, and it is impossible to accurately determine the entry and exit into the branch area. However, in the case of the determination method using the amount of change in the magnetism over time, since it is easier to set the discrimination threshold compared to the determination method based on the amount of magnetism, it is possible to accurately determine the entry and exit into the branch area.

[0009] Also, preferably, the automated guided vehicle has a plurality of magnetic detection sensors arranged in a direction orthogonal to the traveling direction of the vehicle itself as the detection means, a second derivation means for deriving a displacement amount corresponding to each predetermined traveling direction pattern based on the detected amount of magnetism detected by each of the plurality of magnetic detection sensors and the coordinate information corresponding to each arrangement of the plurality of magnetic detection sensors, a traveling direction control means for controlling the traveling direction of the vehicle itself based on the displacement amount corresponding to a predetermined traveling direction pattern when it is determined by the determination means that the vehicle itself has entered the branch area, and it is preferable to be provided with. According to this configuration, it is possible to appropriately guide the automated guided vehicle in the desired traveling direction in the branch area without separately providing a detection means or a magnetic marker for controlling the traveling direction of the automated guided vehicle.

[0010] Also preferably, the automated guided vehicle is provided with travel speed control means for controlling the travel speed of the vehicle itself, when the travel speed control means determines that the vehicle itself has entered the branch area by the determination means, the travel speed of the vehicle itself is controlled to a predetermined speed that is lower than normal, and when it is determined that the vehicle itself has exited the branch area, the travel speed of the vehicle itself may be controlled to the normal speed. According to this configuration, by controlling the travel speed of the automated guided vehicle to a predetermined speed that is lower than normal within the branch area, when the traveling direction of the vehicle itself is changed due to branching, it is possible to suppress the magnetic detection by the detection means from becoming a false detection. Therefore, the automated guided vehicle can be more appropriately guided in the desired traveling direction in the branch area.

[0011] Also preferably, on the guide path other than the branch area, a plurality of types of second magnetic tapes having the magnetism of the other magnetic pole and different magnetic amounts are laid, the automated guided vehicle is preferably provided with operation control means for performing an operation of a command corresponding to the threshold value when the magnetic amount detected by the detection means exceeds a predetermined threshold value corresponding to the magnetic amount of the second magnetic tape. According to this configuration, it is possible to cause the automated guided vehicle to perform an operation corresponding to a desired command at a predetermined position where the magnetic amount of the second magnetic tape changes without separately installing a magnetic marker for a command beside the guide path.

[0012] Also, in order to solve the above problems, the automated guided vehicle of the present invention is an automated guided vehicle that travels on a guide path in a branch area where a first magnetic tape for line tracing having the magnetism of one magnetic pole is laid, and on a guide path other than the branch area where a second magnetic tape for line tracing having the magnetism of the other magnetic pole is laid, In a series of states and includes line tracing detection means for detecting magnetism from the first magnetic tape and the second magnetic tape, In a series of states and derivation means for deriving the amount of temporal change in the magnetism detected by the detection means. ​ Discrimination means for discriminating entry and exit of the host vehicle into the branch area based on the amount of temporal change in the magnetism derived by the derivation means; It is characterized by comprising the same.

[0013] Also, in order to solve the above problems, the branch area entry / exit discrimination method of the present invention is as follows. A detection step of detecting magnetism from the first magnetic tape for line tracing having magnetism of one magnetic pole and the second magnetic tape for line tracing having magnetism of the other magnetic pole by the detection means for line tracing provided in an automated guided vehicle traveling on a guide path in a branch area where the first magnetic tape is laid and a guide path other than the branch area where the second magnetic tape is laid; In a series of states A derivation step of deriving the amount of temporal change in the magnetism detected in the detection step; In a series of states A discrimination step of discriminating entry and exit of the automated guided vehicle into the branch area based on the amount of temporal change in the magnetism derived in the derivation step; It is characterized by including the same.

Effects of the Invention

[0014] According to the present invention, it is possible to grasp that the automated guided vehicle has entered the branch road without separately installing a magnetic marker beside the guide path and by using only the magnetic detection sensor for line tracing.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0016] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to the illustrated examples.

[0017] [Configuration of the Branch Area Entry / Exit Discrimination System] First, with reference to FIG. 1, the configuration of this embodiment will be described. FIG. 1 is a schematic configuration diagram of the branch area entry / exit discrimination system 100 of this embodiment.

[0018] As shown in FIG. 1, the branch area entry / exit discrimination system 100 includes an automated guided vehicle 10 and a guide path 20.

[0019] The automated guided vehicle 10 is, for example, an unmanned trolley robot that transports goods and the like in a factory or warehouse.

[0020] The guide path 20 is a course for guiding the automated guided vehicle 10. The guide path 20 is configured by laying a magnetic tape on the floor surface so as to form a desired course. As shown in FIG. 1, in the guide path 20 of this embodiment, a first branch area A and a second branch area B where the guide path 20 branches into two are provided.

[0021] FIG. 2 is an enlarged view of the first branch area A shown in FIG. 1. As shown in FIG. 2, the guide path 20 in the first branch area A is composed of a first magnetic tape 20A having an S-pole magnetic field. Although not shown, the guide path 20 in the second branch area B is similarly composed of a first magnetic tape 20A having an S-pole magnetic field. On the other hand, the guiding path 20 other than the first branching area A and the second branching area B, that is, the single guiding path 20 without branching, is composed of the second magnetic tape 20B with N - pole magnetism.

[0022] [Configuration of Automated Guided Vehicle] Next, with reference to FIG. 3, the functional configuration of the automated guided vehicle 10 will be described. FIG. 3 is a block diagram showing the functional configuration of the automated guided vehicle 10.

[0023] As shown in FIG. 3, the automated guided vehicle 10 includes a control unit 11, a storage unit 12, an operation unit 13, a communication unit 14, a sensor unit 15, a drive unit 16, etc.

[0024] The control unit (first derivation means, discrimination means, second derivation means, traveling direction control means, traveling speed control means) 11 includes a CPU (Central Processing Unit) that executes various programs stored in the storage unit 12 to perform predetermined calculations and control of each part, and a memory that serves as a work area during program execution (both are not shown in the figure). The control unit 11 executes various processes in cooperation with the programs stored in the storage unit 12.

[0025] The storage unit 12 is composed of a non - volatile semiconductor memory or the like. The storage unit 12 stores system programs and application programs executed by the control unit 11, data necessary for the execution of these programs, etc.

[0026] The operation unit 13 is provided with various function keys, accepts the pressing input of each key by the user, and outputs the operation information to the control unit 11.

[0027] The communication unit 14 is wirelessly connected to a communication network and communicates with external devices connected to the communication network.

[0028] The sensor unit (detection means) 15 includes a plurality (for example, six) of magnetic detection sensors 151 to 156 capable of detecting the magnetism emitted from the magnetic tapes (the first magnetic tape 20A and the second magnetic tape 20B) constituting the guide path 20, and outputs the magnetic flux density (magnetic detection amount) of the magnetism detected by each of the magnetic detection sensors 151 to 156 to the control unit 11.

[0029] FIG. 4 is a front view showing the installation position of the sensor unit 15 in the automated guided vehicle 10. As shown in FIG. 4, the sensor unit 15 is at the front part of the automated guided vehicle 10 (see FIG. 1) and is provided at the lower part of the housing of the automated guided vehicle 10. On the lower surface of the sensor unit 15, the above-described six magnetic detection sensors 151 to 156 are provided so as to face the floor surface respectively. These six magnetic detection sensors 151 to 156 are arranged at equal intervals in a row in a direction (X direction) orthogonal to the traveling direction of the automated guided vehicle 10 (Y direction (front direction of the paper surface in FIG. 4)). Note that the installation position of the sensor unit 15 and the arrangement of the magnetic detection sensors 151 to 156 are merely examples and can be appropriately changed according to, for example, the width of the guide path 20. Also, the number of magnetic detection sensors is not limited to six.

[0030] Here, the storage unit 12 stores data of the respective position coordinates x1 to x6 in the X direction of the magnetic detection sensors 151 to 156 (see FIG. 4) and the position coordinate xc of the center position in the X direction of the sensor unit 15 (see FIG. 4). When the automated guided vehicle 10 is traveling, the control unit 11 performs traveling control so that the difference between the center position xc in the X direction of the sensor unit 15 and the center position in the width direction of the guide path 20 becomes zero, that is, so that the center position xc in the X direction of the sensor unit 15 and the center position in the width direction of the guide path 20 coincide, and outputs instruction information related to the traveling control to the drive unit 16.

[0031] The drive unit 16 controls the operations of wheels and the like based on the instruction information related to the traveling control output from the control unit 11.

[0032] [Operation of Automated Guided Vehicle] Next, with reference to FIGS. 5 and 6, the branch area entry / exit discrimination process of the automated guided vehicle 10 will be described. 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 guide path 20. FIG. 6 is an explanatory diagram showing a method for discriminating entry / exit to / from the branch area. More specifically, the upper part of FIG. 6 is a diagram schematically showing each traveling process (states 1 to 4) when the automated guided vehicle 10 advances in the direction of the arrow in the first branch area A in the figure. Also, the graph in the middle part of FIG. 6 is a graph showing the magnetic flux density (magnetic detection amount) of the magnetism 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 corresponding to the traveling process of the automated guided vehicle 10. Further, the graph in the lower part of FIG. 6 is a graph showing the amount of change in the magnetic flux density over time (the amount of change in the magnetic flux density per unit time) shown in the graph in the middle part of the same figure over time.

[0033] As shown in FIG. 5, when the branch area entry / exit discrimination process is started, first, the control unit 11 of the automated guided vehicle 10 sequentially acquires the magnetic flux density (magnetic detection amount) of the magnetism detected by the third magnetic detection sensor 153 and the fourth magnetic detection sensor 154 (step S1).

[0034] Next, the control unit 11 derives the amount of change in the magnetic flux density per unit time (time change amount [G / s]) based on the magnetic flux density sequentially acquired in step S1 (step S2).

[0035] Next, the control unit 11 determines whether or not the amount of change in the magnetic flux density per unit time (time change amount [G / s]) derived in step S2 is equal to or less than the first threshold value (step S3). Here, the first threshold value is assumed to be a negative value smaller than the normal time when the time change amount is 0.

[0036] In step S3, when it is determined that the change amount of the magnetic flux density per unit time (time change amount [G / s]) derived in step S2 is not less than the first threshold value (step S3; NO), the control unit 11 skips the process of step S4 and advances the process to step S5.

[0037] For example, as shown in the upper part of FIG. 6, when the sensor unit 15 of the unmanned carrier vehicle 10, that is, in state 1, is passing over the second magnetic tape 20B having an N-pole magnetic field, 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 becomes substantially a positive constant value. Therefore, as shown in the graph in the lower part of FIG. 6, in state 1, the change amount of the magnetic flux density per unit time (time change amount [G / s]) is substantially 0. As a result, in state 1, it is determined by the control unit 11 that the value is not less than the first threshold value, and it is not determined that the vehicle has entered the branch area (for example, the first branch area A).

[0038] Also, in step S3, when it is determined that the change amount of the magnetic flux density per unit time (time change amount [G / s]) derived in step S2 is less than or equal to the first threshold value (step S3; YES), the control unit 11 determines that it has entered the branch area, that is, determines that it has started entering the branch area (step S4).

[0039] For example, as shown in the upper part of FIG. 6, when the sensor unit 15 of the unmanned carrier vehicle 10, that is, in state 2, is passing over the boundary line between the second magnetic tape 20B having an N-pole magnetic field and the first magnetic tape 20A having an S-pole magnetic field, 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 gradually decreases from the above-described positive constant value. Therefore, as shown in the graph in the lower part of FIG. 6, in state 2, the change amount of the magnetic flux density per unit time (time change amount [G / s]) becomes a negative value smaller than the first threshold value. As a result, in state 2, it is determined by the control unit 11 that the value is less than or equal to the first threshold value, and it is determined that the vehicle has entered the branch area (for example, the first branch area A).

[0040] Next, the control unit 11 determines whether or not the change amount of the magnetic flux density per unit time (time change amount [G / s]) derived in step S2 is equal to or greater than a second threshold value (step S5). Here, it is assumed that the second threshold value is a positive value greater than the normal time when the time change amount is 0.

[0041] In step S5, when it is determined that the change amount of the magnetic flux density per unit time (time change amount [G / s]) derived in step S2 is not equal to or greater than the second threshold value (step S5; NO), the control unit 11 returns the process to step S1 and repeats the subsequent processes.

[0042] For example, as shown in the upper part of FIG. 6, when the sensor unit 15 of the unmanned carrier 10 in state 3, that is, the sensor unit 15 passes over the first magnetic tape 20A having S-pole magnetism, 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 becomes substantially a negative constant value. Therefore, as shown in the graph in the lower part of FIG. 6, in state 3, the change amount of the magnetic flux density per unit time (time change amount [G / s]) is substantially 0. As a result, in state 3, it is determined by the control unit 11 that it is not equal to or greater than the second threshold value, and it is not determined that the vehicle has exited the branch area (for example, the first branch area A).

[0043] Also, in step S5, when it is determined that the change amount of the magnetic flux density per unit time (time change amount [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 it has exited the branch area, that is, determines that the entry into the branch area has ended (step S6). After performing the process of step S6, the control unit 11 returns the process to step S1 and repeats the subsequent processes.

[0044] For example, as shown in the upper part of FIG. 6, when the sensor unit 15 of the automated guided vehicle 10 in state 4, i.e., is passing over the boundary line between the first magnetic tape 20A with S-pole magnetism and the second magnetic tape 20B with N-pole magnetism, 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 gradually increases from the above-mentioned negative constant value. Therefore, as shown in the graph in the lower part of FIG. 6, in state 4, the change amount of the magnetic flux density per unit time (time change amount [G / s]) becomes a positive value greater than the second threshold value. As a result, in state 4, it is determined by the control unit 11 that it is equal to or greater than the second threshold value, and it is determined that the vehicle has exited from the branch area (for example, the first branch area A).

[0045] Next, with reference to FIG. 7, the travel control process of the automated guided vehicle 10 will be described. FIG. 7 is a flowchart showing the control procedure of the travel control process. This travel control process is a process executed when the automated guided vehicle 10 is traveling on the guide path 20, similar to the above-mentioned branch area entry / exit determination process. The control unit 11 of the automated guided vehicle 10 sequentially derives three types of deviation amounts e, eR, and eL of the following formulas (1) to (3) based on the magnetic flux density (magnetic detection amount) M1 to M6 of the magnetism detected by the respective magnetic detection sensors 151 to 156 at the position coordinates x1 to x6 shown in FIG. 4 and the position coordinates x1 to x6 during the travel on the guide path 20. Note that the following formulas (1) to (3) are merely examples and can be appropriately changed according to, for example, the number of installed magnetic detection sensors.

Number

Number

Number

[0046] As shown in FIG. 7, when the travel control process is started, first, the control unit 11 of the automated guided vehicle 10 determines whether the guide path 20 during travel is within the branch area (step S11).

[0047] In step S11, when it is determined that the guiding path 20 during traveling is not within the branching area, that is, neither within the first branching area A nor within the second branching area B (step S11; NO), the control unit 11 performs traveling 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.

[0048] Also, in step S11, when it is determined that the guiding path 20 during traveling is within the branching area, that is, within the first branching area A or within the second branching area B (step S11; YES), the control unit 11 determines whether the previously specified traveling direction is straight ahead (step S13).

[0049] In step S13, when it is determined that the previously specified traveling direction is straight ahead (step S13; YES), the control unit 11 performs traveling control at the second speed which is lower than the first speed and based on the deviation amount e described above (step S14). However, in such a case (when going straight within the branching area), it is assumed that the deviation amount e is derived by substituting M1 in the above formula (1) with M6 and substituting M2 with M5. Then, the control unit 11 returns the process to step S11 and repeats the subsequent processes.

[0050] Also, in step S13, when it is determined that the previously specified traveling direction is not straight ahead (step S13; NO), the control unit 11 determines whether the previously specified traveling direction is the right direction (step S15).

[0051] In step S15, when it is determined that the previously specified traveling direction is the right direction (step S15; YES), the control unit 11 performs traveling control at the second speed which is lower 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.

[0052] Also, in step S15, when it is determined that the pre-specified traveling direction is not the right direction, that is, the pre-specified traveling direction is the left direction (step S15; NO), the control unit 11 performs traveling control at a second speed lower than the first speed and based on the above-described deviation amount eL (step S17). Then, the control unit 11 returns the process to step S11 and repeats the subsequent processes.

[0053] As described above, the branch area entry / exit determination system 100 of the present embodiment includes the automated guided vehicle 10 and the guide path 20 that guides the automated guided vehicle 10. In the guide path 20 of the branch area (the first branch area A and the second branch area B) of the guide path 20, a first magnetic tape 20A with the magnetism of the S pole (one magnetic pole) is laid. In the guide path 20 outside the branch area, a second magnetic tape 20B with the magnetism of the N pole (the other magnetic pole) is laid. The automated guided vehicle 10 detects magnetism from the first magnetic tape 20A and the second magnetic tape 20B by the sensor unit 15, and the control unit 11 derives the time change amount of the magnetism detected by the sensor unit 15. Based on the derived time change amount of the magnetism, it is determined whether the vehicle itself has entered or exited the branch area (the first branch area A and the second branch area B).

[0054] As a result, when the automated guided vehicle 10 is traveling on the guide path 20, it 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 the entry and exit of the vehicle itself into and out of the branch area based on the derived amount of change in the magnetism over time. Therefore, it is possible to grasp the entry and exit of the automated guided vehicle 10 into and out of the branch area without separately installing a magnetic marker beside the guide path 20. Also, when determining the entry and exit of the automated guided vehicle 10 into the branch area, by using the amount of change in the magnetism over time, it is possible to capture the change in the polarity between the S pole and the N pole while it is in the process of changing. Thus, it is possible to determine the entry and exit into the branch area at a relatively earlier stage than the method of determining the entry and exit into the branch area based on the amount of magnetism detected by the sensor unit 15. Further, in the case of the determination method based on the above-mentioned amount of magnetism, even if the floor surface constituting the guide path 20 has some irregularities, the amount of magnetism detected by the sensor unit 15 fluctuates greatly, making it difficult to set the discrimination threshold, and it is impossible to accurately determine the entry and exit into the branch area. However, in the case of the determination method using the amount of change in the magnetism over time, since it is easier to set the discrimination threshold compared to the determination method based on the amount of magnetism, it is possible to accurately determine the entry and exit into the branch area.

[0055] Also, in the branch area entry / exit determination system 100 of the present embodiment, the automated guided vehicle 10 has, as the sensor unit 15, a plurality of magnetic detection sensors 151 to 156 arranged in a direction orthogonal to the traveling direction of the vehicle itself. Based on the detected amount of magnetism detected by each of the plurality of magnetic detection sensors 151 to 156 and the coordinate information corresponding to each arrangement of the plurality of magnetic detection sensors 151 to 156, the control unit 11 derives the displacement amounts e, eR, eL corresponding to the respective predetermined traveling direction patterns. When it is determined that the vehicle itself has entered the branch area, the traveling direction of the vehicle itself is controlled based on the displacement amount corresponding to the predetermined traveling direction pattern.

[0056] Therefore, according to the branch area entry / exit discrimination system 100 of the present embodiment, the automated guided vehicle 10 can be appropriately guided in a desired traveling direction in the branch area without separately providing a sensor unit or a magnetic marker for controlling the traveling direction of the automated guided vehicle 10.

[0057] Further, in the branch area entry / exit discrimination system 100 of the present embodiment, the automated guided vehicle 10 controls the traveling speed of its own vehicle by the control unit 11. When it is determined that its own vehicle has entered the branch area, the traveling speed of its own vehicle is controlled to a second speed that is lower than normal. When it is determined that its own vehicle has exited the branch area, the traveling speed of its own vehicle is controlled to the normal first speed. Therefore, according to the branch area entry / exit discrimination system 100 of the present embodiment, by controlling the traveling speed of the automated guided vehicle 10 to a second speed that is lower than normal within the branch area, it is possible to suppress the situation where the magnetic detection by the sensor unit 15 becomes false when the traveling direction of its own vehicle is changed due to a branch. Thus, the automated guided vehicle 10 can be more appropriately guided in a desired traveling direction in the branch area.

[0058] As described above, the present invention has been specifically described based on the embodiments. However, the present invention is not limited to the above embodiments and can be modified without departing from the gist thereof.

[0059] For example, in the above embodiment, the guiding paths 20 of the first branch area A and the second branch area B are each composed of a first magnetic tape 20A with an S-pole magnetic field, and the guiding paths 20 other than the first branch area A and the second branch area B are composed of a second magnetic tape 20B with an N-pole magnetic field. However, the guiding paths 20 of the first branch area A and the second branch area B may each be composed of a second magnetic tape 20B with an N-pole magnetic field, and the guiding paths 20 other than the first branch area A and the second branch area B may be composed of a first magnetic tape 20A with an S-pole magnetic field.

[0060] Further, in the above-described embodiment, for example, in the guiding path 20 other than the branching area, a plurality of types of second magnetic tapes 20B having different magnetic amounts are laid. When the automated guided vehicle 10 is traveling on the guiding path 20, if it is determined by the control unit 11 that the magnetic amount detected by the sensor unit 15 exceeds a predetermined threshold value corresponding to the magnetic amount of the above-described second magnetic tape 20B, control may be performed to execute the operation of the command corresponding to the threshold value.

[0061] Further, in the above-described embodiment, the communication unit 14 of the automated guided vehicle 10 is not limited to a configuration in which it is wirelessly connected to a communication network and communicates with an external device connected to the communication network. For example, it may be configured to perform short-range wireless communication with an external device by a communication method of Bluetooth (registered trademark) Low Energy (BLE), or may have both of the above-described configurations.

[0062] In addition to applying the above-described branch area entry / exit discrimination system 100 in the case of transporting goods or the like using the automated guided vehicle 10 in a factory or a warehouse, for example, the branch area entry / exit discrimination system 100 may be applied in the case of performing circuit monitoring of a predetermined course using an unmanned robot equipped with a camera or the like.

Description of Reference Numerals

[0063] 100 Branch area entry / exit discrimination system 10 Automated guided vehicle 11 Control unit 12 Storage unit 13 Operation unit 14 Communication unit 15 Sensor unit 151 to 156 Magnetic detection sensors 16 Driving unit 20 Guiding path 20A First magnetic tape 20B Second magnetic tape A First branch area B Second branch area

Claims

1. An unmanned transport vehicle and a guiding path for guiding the unmanned transport vehicle, wherein in the guiding path of the branching area among the guiding paths, a first magnetic tape having magnetism of one magnetic pole, which is a line tracing first magnetic tape for guiding the unmanned transport vehicle, is laid in a series of states along the guiding path; in the guiding paths other than the branching area, a second magnetic tape having magnetism of the other magnetic pole, which is a line tracing second magnetic tape for guiding the unmanned transport vehicle, is laid in a series of states along the guiding path; the unmanned transport vehicle has detection means for line tracing for detecting magnetism from the first magnetic tape and the second magnetic tape; first derivation means for deriving a time change amount of the magnetism detected by the detection means; discrimination means for discriminating entry and exit of the own vehicle into and from the branching area based on the time change amount of the magnetism derived by the first derivation means; A branching area entry / exit discrimination system, characterized by comprising the above.

2. The unmanned transport vehicle has, as the detection means, a plurality of magnetic detection sensors arranged in a direction orthogonal to the traveling direction of the own vehicle, second derivation means for deriving a displacement amount corresponding to each predetermined traveling direction pattern based on the detected amount of magnetism detected by each of the plurality of magnetic detection sensors and the coordinate information corresponding to each arrangement of the plurality of magnetic detection sensors; traveling direction control means for controlling the traveling direction of the own vehicle based on the displacement amount corresponding to a predetermined traveling direction pattern when it is discriminated by the discrimination means that the own vehicle has entered the branching area; The branching area entry / exit discrimination system according to claim 1, characterized by comprising the above.

3. The unmanned transport vehicle is provided with traveling speed control means for controlling the traveling speed of the own vehicle, wherein when it is discriminated by the discrimination means that the own vehicle has entered the branching area, the traveling speed control means controls the traveling speed of the own vehicle to a predetermined speed lower than normal, and when it is discriminated that the own vehicle has exited from the branching area, the traveling speed control means controls the traveling speed of the own vehicle to the normal speed; The branching area entry / exit discrimination system according to claim 1 or 2, characterized by the above.

4. In the guiding paths other than the branching area, a plurality of types of second magnetic tapes having magnetism of the other magnetic pole and different magnetic amounts are laid. When the amount of magnetism detected by the detection means exceeds a predetermined threshold corresponding to the amount of magnetism of the second magnetic tape, the driverless transport vehicle includes operation control means for performing an operation of a command corresponding to the threshold. The branch area entry / exit discrimination system according to any one of claims 1 to 3, characterized in that.

5. A driverless transport vehicle that travels on a guiding path in a branch area where a first magnetic tape for line tracing with magnetism of one magnetic pole is laid in a series state, and a guiding path other than the branch area where the second magnetic tape for line tracing with magnetism of the other magnetic pole is laid in a series state, Detection means for line tracing that detects magnetism from the first magnetic tape and the second magnetic tape, Derivation means for deriving the amount of temporal change in the magnetism detected by the detection means, Discrimination means for discriminating the entry / exit of the vehicle itself into / from the branch area based on the amount of temporal change in the magnetism derived by the derivation means, A driverless transport vehicle characterized by comprising.

6. A detection step of detecting magnetism from the first magnetic tape and the second magnetic tape by the line tracing detection means provided in a driverless transport vehicle that travels on a guiding path in a branch area where a first magnetic tape for line tracing with magnetism of one magnetic pole is laid in a series state, and a guiding path other than the branch area where the second magnetic tape for line tracing with magnetism of the other magnetic pole is laid in a series state, A derivation step of deriving the amount of temporal change in the magnetism detected in the detection step, A discrimination step of discriminating the entry / exit of the driverless transport vehicle into / from the branch area based on the amount of temporal change in the magnetism derived in the derivation step, A branch area entry / exit discrimination method characterized by including.

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