JP2018163415A - Conveyance system, conveyance method, and automatic conveyance vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system capable of eliminating a host management system, with which conveying of a wagon is started from an arbitrary place to deliver the wagon to a destination.SOLUTION: A conveyance system with which a plurality of AGVs each convey a wagon is disclosed. According to this system, the AGVs each comprise a movement mechanism for making each AGV travel in a predetermined traveling direction, a connection mechanism for connecting the wagon, a sensor for acquiring detection information that is present ahead in the traveling direction, and a controller for controlling the movement mechanism and the connection mechanism. The controller performs control to move an AGV to a position of the wagon by the movement mechanism, to connect the AGV with the wagon by the connection mechanism, and to convey the wagon connected by the movement mechanism to a predetermined position, when recognizing presence of the wagon based on the detection information.SELECTED DRAWING: Figure 1

Description

  The present invention relates to automatic transfer technology for delivering wagons carrying cargo in factories and warehouses.

  In labor-saving assembly factories such as automobiles and home appliances, or distribution warehouses, AGVs (Automated Guided Vehicles) are often used to deliver parts to production sites or move goods. In this case, there are a method in which cargo or a container containing cargo is directly mounted on the AGV, and a method in which the cargo is mounted on a wagon / cart, and the AGV transports the wagon / cart. The former is often used when a relatively small cargo or a small number of items are delivered to one place. In addition, when the cargo is large or many items are delivered to one place, the latter method is often used because of the limitation of the load capacity of the AGV and the convenience of carrying the cargo collectively.

  Further, the method of transporting the wagon is roughly divided into a method of loading the wagon on the AGV and transporting the wagon wheel in a floating state, and a method of transporting the wagon wheel connected to the AGV while the wheel of the wagon is grounded. The method of loading a wagon on an AGV has the advantage that the rolling resistance of the wagon wheel does not affect the running of the AGV because the wheel of the wagon is not grounded during transport, but the facility for loading the wagon on the AGV or AGV A mechanism for lifting the wagon itself is necessary, and the stop time required for loading and unloading becomes longer. On the other hand, the method of connecting and transporting the wagon to the AGV is affected by the rolling resistance of the wagon wheel, but if the wagon has a grippable part, the AGV only needs to be provided with a relatively simple coupling mechanism, and the transport is completed. Since the connection is only disconnected at times, the stop time is short.

  Patent Document 1 and Patent Document 2 are examples of an automatic conveyance system in which an AGV transports a wagon to an instructed place that is not always the same.

JP-A-9-185414 JP 2013-86923 A

  The method of Patent Document 1 is intended to simplify the destination instruction to the AGV by providing an information recording medium in which the destination information is recorded in the wagon. First, when there is no AGV near the wagon to be transported, an empty AGV instructed by the control station to transport the wagon goes to collect the wagon at the designated location. The wagon is equipped with an information recording medium that records destination information. The AGV connected with the wagon to be transported reports to the control station that the wagon is being transported, and reads the destination of the wagon from the information recording medium of the wagon. The AGV controller determines the movement route according to the built-in map or notifies the control station of the destination, the control station determines the movement route, and the AGV moves accordingly. When the AGV reaches the destination, it is disconnected from the wagon and the wagon transport is completed.

  In the method of Patent Document 1, the wagon can be delivered anywhere on the AGV transport path. However, if a wagon to be transported is placed in front of the route while the wagon is being transported, a control station equipped with a route map is indispensable for operation management such as avoiding it, and wireless stations are also installed for communication Since this is necessary, the load in dealing with the layout change becomes large. In addition, it is difficult to use in places where the wireless environment of the place of use is not good, such as a place where there are many radio noise sources and there is a possibility of communication loss, or a place where there are already many wireless communication devices and there is a fear of a war.

  Patent document 2 is one form which utilizes AGV efficiently as a part of an automatic warehouse or a parts collection place. One-way AGV circuit routes are set for loading into the warehouse and unloading from the warehouse, respectively, and the AGV operates according to the state instruction and work ID information from the wirelessly connected AGV control device. A one-way route that is divided into a carry-in route and a carry-out route. A wagon is connected to each of the carry-in route and the carry-out route. Are distinct and do not overlap. Thus, it is claimed that the management data on the management system side is not increased by making the carry-in route and the carry-out route independent.

  However, when parts transportation in an assembly factory is assumed, it is necessary to transport a wagon loaded with parts to the assembly site and collect the empty wagon from the site. Two independent AGV routes are required for the assembly site: delivery of the wagon with the parts and recovery of the empty wagon. In addition, the AGV control device, which is a host device, is still used.

  Therefore, an object of the present invention is to provide a system that starts transporting a wagon from an arbitrary place and delivers it to a destination while allowing an upper management system to be omitted.

  One aspect of the present invention is a transport system in which a plurality of AGVs transport a wagon. In this system, each AGV controls a moving mechanism that causes the AGV to travel in a predetermined traveling direction, a connecting mechanism that connects the wagons, a sensor that acquires detection information in front of the traveling direction, and the moving mechanism and the connecting mechanism. Controller. When the controller recognizes the presence of the wagon based on the detection information, the controller moves the AGV to the wagon position by the moving mechanism, connects the AGV and the wagon by the connecting mechanism, and moves the wagon connected by the moving mechanism to the predetermined position. Carry and control.

  Another aspect of the present invention is an automated guided vehicle. This automatic transport vehicle connects a battery, a motor driven by the battery, an axle to which rotational force is applied by the motor, a wheel connected to the axle, a steering mechanism for changing the direction of the wheel, and a transport object. A connection mechanism, a sensor that acquires detection information in front of the traveling direction, a signal that is received from the sensor, and a controller that controls the motor, the steering mechanism, and the connection mechanism. When the controller recognizes the presence of the object to be transported based on the signal from the sensor, the controller approaches the object to be transported, connects the objects to be transported by the connecting mechanism, and controls to transport to a predetermined position.

  Another aspect of the present invention is a transport method using a plurality of AGVs, a transport path on which the AGV can travel, and a wagon transported by the AGV. In this method, each AGV includes a moving mechanism for driving the AGV, a connecting mechanism for connecting the wagon, a sensor for obtaining detection information in front of the traveling direction, and a controller for controlling the moving mechanism and the connecting mechanism. Prepare. When the controller recognizes the presence of the wagon based on the detection information, the first step of moving the AGV to the position of the wagon by the moving mechanism, the second step of connecting the AGV and the wagon by the connecting mechanism, and the moving mechanism Control is performed to perform a third step of transporting the connected wagon to a predetermined position.

  It is possible to provide a system that starts transporting a wagon from an arbitrary place and delivers it to a destination while making it possible to omit an upper management system.

1 is a schematic plan view illustrating an example of a configuration of Example 1. FIG. It is a schematic perspective view which shows AGV of Example 1, a wagon, a display board, a driving | running | working space, etc. It is a see-through | perspective perspective view which shows AGV of the state which connected the wagon in Example 1. FIG. It is a block diagram which shows the structure of AGV of Example 1. FIG. It is a flowchart which shows the flow of operation | movement of AGV of Example 1. FIG. 6 is a schematic plan view showing an example of a configuration of Example 2. FIG. It is a flowchart which shows the operation | movement flow of AGV of Example 2. FIG. It is a schematic perspective view which shows the example of the approach detection method from the back in Example 2. FIG.

  In the structures of the invention described below, the same portions or portions having similar functions are denoted by the same reference numerals in different drawings, and redundant description may be omitted.

  In the case where there are a plurality of elements having the same or similar functions, the same reference numerals may be given with different subscripts. However, when there is no need to distinguish between a plurality of elements, the description may be omitted.

  Notations such as “first”, “second”, and “third” in this specification and the like are attached to identify the constituent elements, and do not necessarily limit the number, order, or contents thereof. is not. In addition, a number for identifying a component is used for each context, and a number used in one context does not necessarily indicate the same configuration in another context. Further, it does not preclude that a component identified by a certain number also functions as a component identified by another number.

  The position, size, shape, range, and the like of each component illustrated in the drawings and the like may not represent the actual position, size, shape, range, or the like in order to facilitate understanding of the invention. For this reason, the present invention is not necessarily limited to the position, size, shape, range, and the like disclosed in the drawings and the like.

  In one of the embodiments described in detail below, a plurality of AGVs circulate in a track (conveyance path) in a traveling space configured so that a plurality of AGVs can one-way (for example, in a ring shape), and each destination marker is attached. It is a transport system that transports a plurality of wagons individually.

  In this system, each AGV transports a wagon and releases a wagon hook, a camera for visually recognizing the marker, a function for autonomously moving to the wagon position when the marker is visually recognized by the camera, And autonomously traveling to the position specified by the marker.

  When each AGV finds a first wagon that is not carried by another AGV in the driving space, it recognizes the destination from the marker of the first wagon, connects the first wagon with a wagon hook, Transport the first wagon to the destination.

  If the AGV that found the first wagon was transporting another second wagon, it was disconnected from the second wagon that was being transported, the transport was interrupted, and the transported to the discovered wagon It has a function.

  The second wagon whose transportation has been interrupted is discovered by the second AGV traveling around the AGV, and is transported by the second AGV in the same procedure as the first wagon. In addition, each AGV has a function of stopping the transport of the wagon, disconnecting the connection with the wagon, and heading to the charging station when detecting a malfunction such as a decrease in the remaining battery level of the AGV even during the transport of the wagon.

  FIG. 1 is a plan view showing an outline of an embodiment of an autonomous distributed delivery system according to the present invention. In this embodiment, it is assumed that a wagon 201W loaded with a part 700 is transferred from the parts loading station 1002 to each work place 1001, and an empty wagon 201V is transferred from each work place 1001 to the parts loading place 1002. However, it is also possible to transport finished products etc. from each work place 1001 to the parts loading place 1002 or other places.

  The AGV traveling space (conveyance path) 401 connects a parts loading station 1002, a work place 1001, a charging standby station 402 for charging the AGV (in FIG. 1, seven vehicles are prepared), and the like. In FIG. 1, two work places 1001 are surrounded by a conveyance path 401 and the like. The parts loading place 1002 is a space of an arbitrary size arranged along the conveyance path 401. However, the layout of FIG. 1 is an example, and the arrangement of the parts loading place 1002 and the work place 1001 in FIG. 1 can be switched.

  Although the conveyance path 401 has a branch in the path, the conveyance path 401 has a structure that can be circulated in one way, and has a sufficient width that allows the AGV 101 that conveys the wagon 201 to travel safely. That is, the conveyance path 401 is configured so that the AGV 101 is controlled to travel only in one direction and can reach any position even when the traveling direction is limited. According to this configuration, the AGV 101 traveling in one direction can transport the wagon 201 no matter where the wagon 201 is on the transport path 401.

  The transport path 401 is clearly indicated by a white line 405 on the floor surface to distinguish it from other sections, and display boards 501, 502, and 503 indicating places such as a wagon transport destination, an intersection, and a charging regular place are placed in various places. It is. This display board is portable and can be easily adapted to layout changes in the workplace or the like. In addition, there is a necessary display such as a standby line 504 indicating a standby station 403 where the AGV 101 can wait.

  There is room in the charging station 402 where the charging facility for charging the battery 116 of the AGV 101 and the AGV 101C waiting for charging can be parked. The parts loading place 1002 and the work place 1001 have room for the worker 301 to work. The conveyance path 401 may have a plurality of routes such as the conveyance path A406 and the conveyance path B407. In the present embodiment, the AGV 101 includes the battery 116 as a power source. However, a power supply overhead line may be prepared outside the AGV 101, and power may be supplied from the outside.

  A destination display marker 204 indicating the destination of the wagon is provided behind the wagon 201. The AGV 101 basically travels in one direction on the conveyance path 401. The AGV 101W that is transporting the wagon 201W with the load leaving the parts loading place 1002 travels toward each work place 1001 that is a destination (destination) according to the destination display marker 204. At the work place 1001, the worker 301 unloads the loaded part 700 and the unloaded wagon 201V is transported to the parts loading station 1002 by the AGV 101V that transports the unloaded wagon. As will be described in detail later, the wagon 201 and the AGV 101 can be connected and disconnected. For example, the AGV 101D that has been disconnected from the wagon can disconnect the wagon 201 that has been connected so far, and then reconnect to another wagon 201.

  FIG. 2 is a schematic perspective view showing the AGV 101, the wagon 201, the display board 501, the conveyance path 401, and the like of this embodiment. AGV 101 is a front camera 109, a controller 115 that processes camera images and controls AGV travel, a battery 116 that is a power source, a front wagon hook (front pressing plate) 107 and a rear wagon hook (rear pressing) for connecting to the wagon. Plate) 108, front operation indicator 112 and rear operation indicator 113, rear AGV detector 114, front obstacle detection laser sensor 110, contact sensor 111 for collision emergency stop, wheel 117, etc. . The AGV 101 moves in the direction of the arrow 299 (traveling direction) in the figure.

  The size of the AGV 101 in this example is the clearance between the lower floor surface of the wagon 201 and the height and width of the vehicle body that can travel between the wagon wheels. The AGV 101 analyzes the position and posture of the white line 405 captured in the field of view 118 of the front camera 109 by the controller 115, recognizes the left and right positions and the traveling direction of the own vehicle in the conveyance path 401, and stably travels on the conveyance path 401. Control as you do. Self-position recognition within the entire transport path 401 is performed by recognizing the display boards 501 provided at various places, and if the display boards 501, 502, and 503 are not in the field of view, estimated travel is performed by odometry from the previously recognized position. To do.

  The display board 501 has a predetermined size, and characters such as characters, QR codes (registered trademark), and colors associated with the display board position are written. When these letters and symbols include instructions or information for the AGV 101 There is also.

  The wagon 201 is, for example, four wheels including wheels 205 and 207. A wheel (swivel caster) 205 is configured such that at least two front wheels are freely directional, and a destination display marker 204 is attached to the rear. The destination display marker 204 can be constituted by a plate or sheet that is hooked on a wagon and attached, or is inserted in a mounting pocket provided in the wagon in advance, or a display whose display can be changed. The destination display marker 204 has a fixed attachment position and size, and characters such as a character indicating a delivery destination of the wagon, a QR code, and a color are displayed.

  The AGV 101 recognizes the position and orientation relative to the vehicle from the size (viewing angle) and position of the destination display marker 204 captured in the field of view 118 of the front camera, and collates the character or symbol indicating the delivery destination. By doing so, the delivery destination of the wagon 201 is recognized. At the same time, it is determined whether or not the wagon 201 is in the transport path or whether there is another AGV that is transporting the wagon 201, and the wagon 201 is in the transport path 401 and no other AGV is transporting the wagon 201. If it is determined, the operation of connecting the wagon 201 and transporting it to the destination is started.

  The presence / absence of another AGV that is transporting the wagon 201 depends on whether the other AGV can be recognized under the wagon 201 based on the image of the front camera 109, or whether the other AGV's rear operation indicator is visible. Can be judged. In addition, there is a method in which the AGV 101 is provided with a function of hiding the destination marker of the wagon 201 being transported by a cover so that other AGVs do not recognize the presence of the wagon.

  The driving method is assumed to be front-wheel-drive front-wheel steering, but there may be methods such as all-wheel drive and skid steering in consideration of the characteristics of the wagon and the driving space. The inside of the conveyance path 401 is displayed from the view of the front camera 109 of the AGV 101 due to the swinging of the vehicle body, the destination display marker 204 placed in the display board 501 and the traveling space, and the backward operation display attached to the rear of the AGV. The lamp 113 and the white line 405 indicating the traveling space are flat so as not to come off.

  Furthermore, the normal operation of the AGV 101 may require a map having distance information for the controller 115 to go to the destination. However, in this embodiment, if the display board 501 is installed at an appropriate location such as an intersection, the map only needs to be route information, distance information is not necessary, and the response to the layout change of the workplace becomes easier. The AGV 101 often has a cover, but the cover is omitted in FIG. 2 to explain the inside.

  FIG. 3 is a schematic perspective view showing the AGV 101 in a state where the wagon 201 in this embodiment is connected. As shown in FIG. 3, the wagon is connected so that the rotation mechanism 206 of the wheel 205 configured to be freely movable on both front sides of the wagon 201 is held between the front wagon hook 107 and the rear wagon hook 108 on both sides of the AGV 101. To do.

  In FIG. 3, the main body of the wagon 201 is not drawn for the sake of explanation. In a general directional wheel, a connecting portion between the wheel and the wagon body is a cylindrical rotating mechanism, and even if this portion is sandwiched between objects having low friction, the direction change of the wheel is not hindered.

  AGV101, which entered under the wagon 201 and determined that it passed the wagon rear wheel 207 from the wagon position and orientation recognition with the destination display marker 204 and the odometry measurement of the AGV101 itself, unfolds the rear wagon hook 108 first, and slowly Advance. After determining that the rotation mechanism portion 206 hits the rear wagon hook 108 with a load sensor or the like, the front wagon hook 107 is swung out and sandwiched while continuing to advance slowly.

  Since the friction is low when the universal wheel rotating mechanism is sandwiched between the front wagon hook 107 and the rear wagon hook 108, a force to move the wheel 205 to the outside acts on the AGV 101. However, since the wheel 205 on the opposite side of the wagon is also sandwiched and tries to move outside, the wagon can be firmly connected by holding the wheels on both sides. In this connection method, the force pushing the wagon forward is mainly handled by the rear wagon hook 108, and the force pushing the rear is mainly handled by the front wagon hook 107. By installing a clutch in the drive mechanism of the rear wagon hook 108, when delivering the wagon to the destination and releasing the connection, the rear wagon hook is free by releasing the clutch connection of the rear wagon hook 108 at the moment of stopping. Therefore, the AGV 101 can resume moving forward, and the stop time during disconnection can be shortened.

  The above is an example of a method for holding the wagon 201 by the AGV 101. In addition, it is possible to adopt a method in which the wagon 201 is coupled with an electromagnet or the entire wagon 201 is lifted and connected.

  FIG. 4 is a control block diagram of the AGV 101 of this embodiment. A battery 116 as a power source supplies power to each part of the AGV 101 through a power line (not shown). Examples of components that require mechanical driving force include a motor 801 that drives a wheel 117 via an axle (not shown), a steering mechanism 802 that steers the wheel, and a connecting mechanism 803 that connects a wagon. In the example of FIG. 3, the coupling mechanism 803 is specifically composed of a front wagon hook 107 and a rear wagon hook 108.

  The control system includes a controller 115 and a front camera 109, a front obstacle detection laser sensor 110, a contact sensor 111 for emergency stop at the time of collision, and a rear AGV detector 114 that provide information to the controller 115. . These elements are connected by a data bus (not shown). The controller 115 can be composed of, for example, a one-chip microcomputer.

  The one-chip microcomputer includes, for example, a processor (CPU) 804 that processes information, a memory (MEM) 805 that stores information, and an interface (I / F) 806 for exchanging information with the outside. In the present embodiment, the processing such as calculation and control is performed by a program stored in the memory 805 being executed by the processor 804, so that the determined processing is performed by other hardware (motor 801, steering mechanism 802, connection mechanism 803). Etc.) and decided to realize. However, in this embodiment, functions equivalent to the functions configured by software can be realized by hardware such as FPGA (Field Programmable Gate Array) and ASIC (Application Specific Integrated Circuit).

  In this embodiment, the AGV 101 basically can operate independently without the control of the host device, and the program for controlling the operation is pre-loaded from the interface 806 to the memory 805 constituted by a flash memory or the like. Processing is performed by writing and reading by the processor 804 as necessary.

  FIG. 5 is a control flow of the AGV 101 executed by the controller 115 of the present embodiment. A solid line indicates a flow of processing, and a dotted line indicates a flow of information. The mechanism of the automatic wagon conveyance system in the present embodiment will be described with reference to FIG. 1 as appropriate.

  As seen in FIG. 1, there are a plurality of AGVs 101 in the transport system, and the transport path 401 is operated in one way. The AGV 101 that has not transported the wagon continues its lap until a wagon to be transported is found. The worker 301 attaches a destination display marker 204 to the wagons 201 and 203 that he / she wants to carry, and puts them on the conveyance path 401.

  When the AGV 101 finds a wagon to be transported in the transport path 401 (not transported to the AGV), the AGV 101 connects to the wagon and transports it to the destination of the wagon.

  The processing flow will be described with reference to FIG. When the operation starts, the AGV 101 travels in one line on the conveyance path 401 at a predetermined speed (S501). The travel route may be programmed in advance by storing map data in the memory 805, or may be controlled based on information on the display boards 501, 502, and 503 acquired by the front camera 109. Each AGV 101 can have its own route. The traveling speed is arbitrary, but may be a constant speed (for example, 5 km / h).

  In this embodiment, the AGV 101 is basically used when the wagon 201 is being transported to the destination, when the wagon 201 that has not been transported to the other AGV 101 is found in the forward direction, or when maintenance such as a decrease in the battery 116 is required. Except for the above, the inside of the conveyance path 401 is circulated freely as described above.

  Based on the image of the front camera 109, the AGV 101 constantly monitors the presence / absence of the wagon 201 that is not transported to other front AGVs (S502). When a wagon to be transported is found, it is determined whether the AGV itself is transporting the wagon (S503). The determination can be made by the controller 115 confirming the state of the coupling mechanism 803. If the AGV itself is carrying the wagon, the connection with the wagon 201 being carried is released (S504). The wagon 201 that was being transported is temporarily left on the spot.

  AGV101, which has been disconnected from the wagon 201 being transported, goes to transport the discovered wagon. That is, the controller 115 of the AGV 101 controls the motor 801, the steering mechanism 802, the coupling mechanism 803, and the like based on the image acquired by the front camera 109, approaches the AGV 101 to the front wagon 201, and couples them (S505). ). At this time, information on the front obstacle detection laser sensor 110 and the emergency stop contact sensor 111 is also used as necessary.

  While approaching the front wagon 201, the front camera 109 acquires an image of the destination display marker 204 of the front wagon 201, and determines the destination of the wagon based on the acquired image. And it moves to the destination according to the destination display marker of the wagon (S506).

  On the other hand, the wagon that has been disconnected in step S504 is discovered by the AGV that does not connect the subsequent wagon and is carried to the destination. If the succeeding AGV is also connected to the wagon, the AGV similarly releases the connection of the previously connected wagon and pulls the front wagon. In this way, by taking over the wagon 201 between the AGVs 101, all the wagons finally arrive at their destinations.

  The wagon 202 that has arrived at the destination and has been disconnected from the AGV 101 is pulled out of the conveyance path 401 by the worker 301. The AGV 101 that has disconnected the wagon 202 continues to patrol (S501).

  If the AGV 101 determines that its battery level has decreased (S507), it performs a charging process (S508). In the charging process, for example, the AGV 101 moves to the charging standby place 402, performs charging, and returns to the orbiting behavior of the conveyance path 401 again after the charging is completed.

  When the AGV 101 detects that the remaining battery level is low, if the wagon 201 is being transported, the vehicle is disconnected from the wagon 201 and placed on the transport path 401 before entering the charging standby station 402. The neglected wagon is transported by another subsequent AGV 101.

  When there are a plurality of routes such as the transport paths A406 and B407, the routes can be set in advance so that the traffic is not biased, or to preferentially circulate in the direction where the wagon is transported more frequently. If the situation changes during operation, it is also possible to change the priority route by changing the display on the display board 503 and issuing an instruction.

  FIG. 6 is a schematic diagram showing an example of an autonomous distributed delivery system according to the second embodiment of the present invention. In this embodiment, the transport path 401 has a one-way and circular structure, but there are standby stations 403A, 403B, 403C, 403D and seven charging standby stations 402 (the number is arbitrary) in the transport path. Exists.

  In this embodiment, the number of standby units at the standby station 403 and the charging standby station 402 is the same as the total number of AGVs 101 to be operated. If the total number is the same, all the AGVs 101 can be in a standby state at any one of the standby places. The condition is not essential, but if the number of waiting places is larger, the space is wasted, and if the number of AGVs 101 is larger, the AGV 101 that cannot take a waiting state appears.

  The waiting places 403A, 403B, 403C, and 403D are provided at positions where the waiting AGV can be found by the front camera 109 or the like when the wagon to be transported is placed on the transport path.

  FIG. 7 is a control flow of the AGV 101 executed by the controller 115 of the present embodiment. A solid line indicates a flow of processing, and a dotted line indicates a flow of information.

  In the basic operation of the AGV 101, as in the first embodiment, when a wagon 201 that is not being transported is found on the transport path 401 in the field of view 118 of its own front camera 109 (S502), the wagon 201 is connected (S505). ) To the destination (S506).

  The difference in control is that the AGV101 is not being transported by the wagon 201, and in the situation where no wagon has been found, except for the case where the remaining battery level is low or another AGV approaches from the rear, The vehicle travels to the waiting station 403, stays at the waiting station, and waits (basic state: S701). That is, the AGV 101 that has arrived at the destination and released the connection of the wagon 201 moves forward to the waiting place 403 ahead and waits there (S703).

  When the rear AGV detector 114 detects that another AGV 101 has approached from behind during standby (S702), the vehicle departs from the standby station 403 even without a wagon. After departure, the vehicle moves forward to the nearest standby station 403, stays at the standby station, waits (S703), and returns to the basic state (S701).

  Although not shown in FIG. 7, when the AGV 101 senses a decrease in the battery 116, as in the first embodiment of FIG. However, in this embodiment, the level at which the remaining battery level is detected is set so that even if the remaining battery level is detected while the wagon 201 is being transported, the wagon 201 can be delivered to the charging standby station 402. Pull up. As a result, if a decrease in the remaining battery level is detected during the transportation of the wagon, the wagon can be delivered to the charging station 402 after the delivery of the wagon without stopping the delivery of the wagon.

  Note that the AGV 101 that does not require charging can use the charging standby station 402 as a normal standby station 403. In this case, control may be performed so that the AGV 101 that is in charge has a standby priority so that the AGV 101 that is in charge is not driven out of the charge waiting place 402 during charging.

  The processing flow of the transport system in the present embodiment will be described based on examples with reference to FIG. When the AGV 101P waiting in the waiting station 403C in the lower center of the figure finds a wagon 201S to be transported within the field of view of the front camera 109, the AGV 101P starts to transport from the waiting station 403C through the path 601.

  The AGV 101P connects the wagons 201S and conveys the wagons 201S through the path 602. AGV101P arriving at the destination 603 of the wagon breaks the connection with the wagon 201S and tries to go to the waiting place 403A ahead of the road. Here, the AGV 101K is waiting at the front standby station 403A, but the AGV 101K proceeds to the front standby station 403B as the AGV 101P approaches from the rear (processing S702 and S703 in FIG. 7).

  AGV101L is waiting at 403B, but AGV101L detects the approach of AGV101K from the rear, departs from waiting station 403B, and goes to the waiting station that is free ahead by way of route 604 (processing in FIG. 7). S702 and S703).

  Since the standby station 403C where the AGV 101P was located is vacant, the AGV 101L enters the standby station 403C and enters a standby state. Similarly, when the AGV 101N that is transporting the wagon approaches the AGV 101M that is waiting at the waiting place 403D from behind, the AGV 101M that has detected the approach of the AGV 101N leaves the waiting place 403D and heads for an empty waiting place ahead.

  However, since the charging waiting place 402 is blocked, the AGV 101M arrives at the waiting place 403A. The AGV 101N that is transporting the wagon passes through the waiting station 403D, disconnects from the wagon at the destination 605 of the wagon, and then heads to the waiting station that is open ahead and arrives at the waiting station 403A.

  At this time, the AGV 101M is in the waiting place 403A, but the AGV 101M detects the approach of the AGV 101N and proceeds to the waiting place 403B, and the AGV in the waiting place 403B advances to the waiting place 403D that is vacant ahead. When the AGV in the waiting place detects that its battery level is low, it leaves the waiting place and goes to the charging waiting place 402 without finding the wagon. In the charging waiting place 402, each AGV advances one by one as in the previous example, and the leading AGV 101Q departs.

  FIG. 8 is a structural perspective view of the AGV 101 of this embodiment. There are several methods for detecting the approach of the AGV from the rear. As an example, as shown in FIG. 8, the rear AGV detector 114 of the waiting AGV 101-1 is composed of a laser receiver and a circuit. When the laser beam of the front obstacle detection laser sensor 110 of 2 is detected, there is a method that the AGV 101-2 is regarded as approaching.

  In addition, there is a method in which the rear AGV detector 114 is a camera and the distance is measured by recognizing an image of the forward operation indicator lamp 112 at the left and right front portions of the AGV 101-2 and having a predetermined interval. A method of recognizing the shape of the AGV vehicle body can also be adopted.

  Alternatively, the rear AGV detector 114 is used as a light receiver of a specific laser light signal pattern, and the approaching AGV 101-2 is using the front camera 109 and is moving backward in the rear left and right of the AGV 101-1 with a predetermined interval. When the indicator lamp 113 recognizes the image, measures the distance, and approaches, the laser beam of the obstacle detection laser sensor blinks in a specific pattern, and when the signal pattern is received by the rear AGV detector 114, the rear There is a method in which AGV 101-1 determines that there is AGV 101-2 approaching.

  In this way, by providing a waiting place, it is possible to reduce the travel of the AGV 101 when the amount of wagon conveyance is small, and to save energy. Here, for the sake of explanation, it has been described that the events here have occurred independently, but in reality, they may occur in parallel.

  The transport mechanism shown in the first and second embodiments is not necessarily independent. When there are a large number of wagons to be transported, the transport system operates according to the first embodiment, and when there are few wagons to be transported, the AGV is charged. There may also be an operation method of evacuating to a place or the like and shifting to the mechanism of the second embodiment.

  Furthermore, there is also an intermediate operation in which the number of AGVs that are traveling is reduced by switching the number of AGVs that are waiting at the charging standby place. In the case of this intermediate operation, not all AGVs are waiting at the waiting place. Therefore, the average waiting time until the start of the wagon transfer is shortened compared with the second embodiment, and the AGV waiting at the waiting place is used. There is a certain amount of energy saving compared to Example 1. Further, there may be a method in which AGV is assigned to each conveyance path in FIG. 1 and the mechanism of operation is changed for each conveyance path.

  According to the embodiment described above, by preparing a one-way travel space, a self-supporting and distributed transport system that transports a wagon from any place to a destination without centrally managing the operation of each AGV is constructed. it can.

  The present invention is not limited to the embodiments described above, and includes various modifications. For example, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace the configurations of other embodiments with respect to a part of the configurations of the embodiments.

101 AGV
107 Front wagon hook (front holding plate)
108 Rear wagon hook (rear holding plate)
109 Front camera
115 controller
201 Wagon
204 Destination display marker
205 wheels (free casters)
206 Rotation mechanism
207 Wagon rear wheel
301 workers
401 AGV traveling space (conveyance path)
501 display board
502 Display board
503 display board

Claims (15)

A transport system in which a plurality of AGVs transport a wagon,
Each of the AGVs
A moving mechanism for causing the AGV to travel in a predetermined traveling direction;
A connecting mechanism for connecting the wagons;
A sensor for obtaining detection information in front of the traveling direction;
A controller for controlling the moving mechanism and the coupling mechanism;
The controller is
When the presence of the wagon is recognized based on the detection information, the AGV is moved to the position of the wagon by the moving mechanism,
The AGV and the wagon are connected by the connecting mechanism,
The wagon connected by the moving mechanism is transported to a predetermined position and controlled.
Conveying system. The AGV runs on the transport path,
The transport path is
Even if the traveling direction is limited to one direction, it is configured to reach any position,
The transport system according to claim 1. The AGV sensor is a camera, and includes a front of the traveling direction in the field of view,
The wagon includes a marker,
The controller recognizes the presence of the wagon when the marker is recognized based on an image acquired by the camera.
The transport system according to claim 1. The AGV sensor is a camera, and includes a front of the traveling direction in the field of view,
The wagon includes a marker,
When the controller recognizes the marker based on the image acquired by the camera, the controller acquires information indicating a predetermined position for transporting the wagon based on the image of the marker.
The transport system according to claim 1. A plurality of wagons transported by the AGV;
The controller is
When the first wagon is being transported and the presence of the second wagon is recognized, the connection with the first wagon is released,
Moved to the position of the second wagon by the moving mechanism;
Connecting the second wagon by the connecting mechanism;
The second wagon is transported to a predetermined position by the moving mechanism, and control is performed.
The transport system according to claim 1. Each of the AGVs
When recognizing the presence of the wagon based on the detection information, it is controlled by the controller so that it is traveling at a predetermined speed.
The transport system according to claim 2. Each of the AGVs
When recognizing the presence of the wagon based on the detection information, it is controlled by the controller so as to be waiting at a waiting place.
The transport system according to claim 2. Each of the AGVs
A rear sensor for acquiring detection information behind the traveling direction;
The controller is
While waiting at the waiting place, when recognizing the presence of another AGV based on the rear detection information detected by the rear sensor, the moving mechanism moves from the waiting place in the traveling direction.
8. The transport system according to claim 7. Battery,
A motor driven by the battery;
An axle provided with rotational force by the motor;
Wheels connected to the axle;
A steering mechanism for changing the direction of the wheel;
A connection mechanism for connecting the objects to be conveyed;
A sensor that acquires detection information in front of the traveling direction;
A controller that receives a signal from the sensor and controls the motor, the steering mechanism, and the coupling mechanism;
The controller is
When the presence of the transport object is recognized based on a signal from the sensor, control is performed to approach the transport object, connect the transport object by the connection mechanism, and transport the transport object to a predetermined position. ,
Automated transport vehicle. The controller is
When the transport object is being transported, control is performed so that the vehicle travels at a predetermined speed, except when the presence of the transport object is recognized, and when maintenance is required.
The automated guided vehicle according to claim 9. A rear sensor for obtaining rear detection information in a direction opposite to the sensor;
The controller is
When the transport object is being transported, when the presence of the transport object is recognized, and when maintenance is required, control is performed to stop at a predetermined position, and
Based on the signal from the rear sensor, when recognizing the presence of another automated guided vehicle, control is performed so as to move from the predetermined position.
The automated guided vehicle according to claim 9. The coupling mechanism is
A first member that comes into contact with a part of the transport object from the rear side in the running direction and a second member that comes into contact with the front side in the running direction are provided. It is controlled so that the contact of the second member is performed later.
The automated guided vehicle according to claim 9. A transport method using a plurality of AGVs, a transport path on which the AGV can travel, and a wagon transported by the AGV,
Each of the AGVs
A moving mechanism for running the AGV;
A connecting mechanism for connecting the wagons;
A sensor for acquiring detection information in front of the traveling direction;
A controller for controlling the moving mechanism and the coupling mechanism;
The controller is
A first step of moving the AGV to the position of the wagon by the moving mechanism when recognizing the presence of the wagon based on the detection information;
A second step of connecting the AGV and the wagon by the connecting mechanism;
A third step of transporting the wagon connected by the moving mechanism to a predetermined position;
The conveyance method that controls to perform. The controller is
The AGV performs control so as to travel in one direction along the transport path,
The transport path is
The AGV is controlled so as to travel only in one direction on the transport path, and is configured to reach an arbitrary position even when the traveling direction is limited.
The transport method according to claim 13. A plurality of wagons transported by the AGV;
The controller is
A fourth step of releasing the connection between the AGV and the first wagon when the AGV is transporting the first wagon and recognizes the presence of the second wagon;
A fifth step of moving the AGV to the position of the second wagon by the moving mechanism;
A sixth step of connecting the AGV and the second wagon by the connecting mechanism;
A seventh step of transporting the second wagon connected by the moving mechanism to a predetermined position;
The conveyance method according to claim 14, wherein control is performed so as to perform.

Images