Transport facility

Abstract

Provided is a transport facility comprising a plurality of transport vehicles and a control system, wherein: a travel path includes a loop path; and, when a deadlock state occurs, if it is impossible to resolve the deadlock state through the execution of first deadlock resolution processing for resolving the deadlock state by changing the destinations of some of a plurality of contributing-factor transport vehicles, which are a plurality of transport vehicles that are each a contributing factor to the deadlock state, from the initial destinations thereof, the control system executes second deadlock resolution processing in which all of the contributing-factor transport vehicles are moved toward the loop path and caused to circulate through the loop path, and then the contributing-factor transport vehicles are respectively moved toward the initial destinations.

Description

Transport Facility

[0001] The present invention relates to a transport facility.

[0002] For example, Japanese Patent Application Laid-Open No. 2006-268769 (Patent Document 1) discloses a technology related to a transport facility. Hereinafter, the reference numerals shown in parentheses in the description of the background art are those of Patent Document 1.

[0003] The transport facility of Patent Document 1 includes a plurality of transport vehicles (2) that travel along a travel route network (3) to transport articles, and a plurality of stations (S). The travel route network (3) is formed in a grid pattern by a combination of a plurality of movement routes (1), and thus includes a plurality of intersections (D1, D2). A plurality of evacuation locations (K) for the transport vehicles (2) to evacuate are provided in the travel route network (3) so as to correspond to the plurality of intersections (D1, D2). The evacuation location (K) is branched and connected to one of the plurality of movement routes (1) that merge at the intersection (D1, D2).

[0004] Japanese Patent Application Laid-Open No. 2006-­268769

[0005] In the transport facility of Patent Document 1, when a so-called deadlock state occurs in which a plurality of transport vehicles attempting to pass through one intersection interfere with each other's movement and stop, one of these transport vehicles is evacuated to an evacuation location corresponding to the intersection. As a result, the remaining transport vehicles can sequentially pass through the intersection, and thus the deadlock state is resolved. However, it may be difficult to separately provide such evacuation locations corresponding to each intersection, or the area required for installing the transport facility may increase due to providing such evacuation locations.In such a case, it is necessary to resolve the deadlock state by means different from the above.

[0006] Therefore, in a transport facility including a plurality of transport vehicles that travel along a travel route to transport articles, it is desired to provide a technology that can appropriately resolve a deadlock state and direct the transport vehicle that caused the deadlock state toward the destination.

[0007] The transport equipment according to this disclosure comprises a plurality of transport vehicles that travel along a travel path to transport goods, and a control system that controls the plurality of transport vehicles, wherein the X direction is defined as a specific direction along a horizontal plane, and the Y direction is defined as a direction that intersects the X direction in an up-down view, the travel path includes a plurality of Y-direction paths which are paths along the Y direction, a plurality of X-direction paths which are paths along the X direction and each intersects at least one of the Y-direction paths, and a circular path which is composed of a pair of the X-direction paths and a pair of the Y-direction paths, and the control system is If, along the aforementioned travel path, a deadlock occurs in which multiple transport vehicles moving toward their respective destinations obstruct each other's movement and stop, and if the deadlock cannot be resolved by executing a first deadlock resolution process, which resolves the deadlock by changing the destination of some of the multiple transport vehicles that are causing the deadlock from their original destination, then a second deadlock resolution process is executed, which moves all of the multiple transport vehicles toward the circular path and makes them circle the circular path, and then moves each of the multiple transport vehicles that are on the circular path toward their original destination.

[0008] With this configuration, even if the deadlock state is not resolved by the first deadlock resolution process, which changes the destination of some of the multiple factor transport vehicles, the deadlock state can be resolved with high reliability without complex control processing of the transport vehicles. In addition, since each transport vehicle is moved from the circular path towards the destination point, the possibility of the deadlock state occurring again can be reduced. Thus, with this configuration, the deadlock state can be resolved appropriately while directing the transport vehicles that were causing the deadlock state towards their destinations.

[0009] Further features and advantages of the conveying equipment will become clear from the following description of exemplary and non-limiting embodiments, which will be explained with reference to the drawings.

[0010] Schematic plan view of the transport equipment Schematic plan view of the transfer position and transfer target location Control block diagram Schematic plan view of a transport vehicle in a deadlock state Schematic plan view of a transport vehicle in a deadlock state Schematic plan view of a transport vehicle in a deadlock state Schematic plan view of a transport vehicle circulating along a circular route Control flow diagram

[0011] Below, an embodiment of the conveying equipment 1 will be described with reference to the drawings.

[0012] As shown in Figures 1 and 3, the transport equipment 1 comprises a plurality of transport vehicles 10 that travel along a travel path 2 to transport goods W, and a control system 100 that controls the plurality of transport vehicles 10. In this embodiment, a plurality of transfer target locations 6 are provided along the travel path 2. Each of the plurality of transport vehicles 10 travels along the travel path 2 to transport goods W to its respective transfer target location 6. In the following, a specific direction along the horizontal plane will be described as the X direction, and a direction intersecting the X direction in an up-down view will be described as the Y direction. In this example, one side in the X direction will be referred to as the first X direction side X1, and the opposite side as the second X direction side X2. Similarly, one side in the Y direction will be referred to as the first Y direction side Y1, and the opposite side as the second Y direction side Y2.

[0013] The travel path 2 includes a plurality of Y-direction paths 3 that are paths along the Y direction, a plurality of X-direction paths 4 that are paths along the X direction, each intersecting with at least one Y-direction path 3, and a circular path 5 composed of a pair of X-direction paths 4 and a pair of Y-direction paths 3. In this embodiment, the travel path 2 includes a grid-like path (grid-like path 18) formed by the intersection of the plurality of Y-direction paths 3 and the plurality of X-direction paths 4. Specifically, the plurality of Y-direction paths 3 are arranged to be spaced apart from each other in the X direction, and the plurality of X-direction paths 4 are arranged to be spaced apart from each other in the Y direction. The grid-like path 18 is formed by the plurality of Y-direction paths 3 and the plurality of X-direction paths 4 arranged in this manner being orthogonal to each other in a vertical view. In this example, the grid-like path 18 formed as described above and the circular path 5 are arranged adjacent to each other. Here, the circular path 5 is arranged on the first Y-direction side Y1 with respect to the grid-like path 18 (dotted line in Figure 1).

[0014] In this embodiment, the transport vehicle 10 is configured to transfer the item W between the transfer target location 6 and the transfer target location 6 at the transfer position 7, with the transfer position 7 being the position corresponding to each transfer target location 6 in the travel path 2. Here, the transport vehicle 10 is configured to be able to travel along both the Y-direction path 3 and the X-direction path 4. In this example, guide rails (not shown) are arranged along both the Y-direction path 3 and the X-direction path 4. The transport vehicle 10 travels along the travel path 2, guided by the guide rails.

[0015] As shown in Figure 3, the transport vehicle 10 comprises a traveling device 13, a transfer device 14, and a control unit 12. The traveling device 13 comprises a traveling motor (not shown) as a drive source and a plurality of wheels (not shown). The traveling motor provides the propulsion force that allows the transport vehicle 10 to travel along the travel path 2. Here, the plurality of wheels include wheels that roll on guide rails along the X-direction path 4 and wheels that roll on guide rails along the Y-direction path 3. The transfer device 14 supports the article W and is configured to transfer the article W between the transfer target location 6 and other locations. Here, the transfer device 14 is a fork type, but it can also be a conveyor type. The transport vehicle 10 is not limited to such a tracked trolley, and may be an unmanned transport vehicle that autonomously travels along the travel path 2. The transport vehicle 10 may also be an overhead transport vehicle that suspends and supports the article W for transport.

[0016] The control unit 12 controls the traveling device 13 and the transfer device 14, as well as other elements (for example, various sensors such as obstacle sensors). In this embodiment, the transport equipment 1 further includes a control device H that controls the entire equipment. The control unit 12 is configured to communicate freely with the control device H. The control unit 12 controls the traveling device 13 to move the transport vehicle 10 toward a predetermined transfer target location 6. In this embodiment, the control unit 12 controls the traveling device 13 and the transfer device 14 based on command information from the control device H. The control unit 12 and the control device H include, for example, a processor such as a microcomputer, peripheral circuits such as memory, etc. Each function is realized through the cooperation of this hardware and a program executed on the processor such as a computer.

[0017] In this embodiment, the transfer position 7 is set on the Y-direction path 3. Also, no transfer position 7 is set on the circular path 5. To elaborate, the transport vehicle 10 (here, the transfer device 14) moves the article W along the X-direction at the transfer position 7. This allows the transport vehicle 10 to transfer the article W to the transfer target location 6. In this embodiment, multiple transfer positions 7 are set on the Y-direction path 3 so as to be adjacent to the corresponding transfer target location 6. Also, the transfer position 7 is set on the Y-direction path 3 which is included in the grid-like path 18. The transfer target location 6 is located in the area enclosed by the Y-direction path 3 and the X-direction path 4 on the grid-like path 18.

[0018] In this embodiment, the circular path 5 is configured to intersect with all Y-direction paths 3 included in the travel path 2. In this example, the circular path 5 is formed by two X-direction paths 4 aligned in the Y direction and two Y-direction paths 3 that are furthest apart in the X direction from among the multiple Y-direction paths 3. The two X-direction paths 4 that form the circular path 5 are the two X-direction paths 4 that are located furthest to the first Y-direction side Y1 from among the multiple X-direction paths 4. Note that no area is formed between the two X-direction paths 4 that form the circular path 5, for example, in which a transfer target location 6 can be placed. In this example, the remaining Y-direction paths 3 located inward in the X direction are connected to the two Y-direction paths 3 that form the circular path 5 and are furthest apart in the X direction, so as to intersect with the circular path 5. In the circular path 5, the travel direction of the transport vehicle 10 is set to one direction (white arrow in Figure 1).

[0019] In this example, as shown in Figures 1 and 2, the transport equipment 1 is equipped with a storage rack 9. The storage rack 9 is equipped with multiple storage compartments, which serve as transfer target locations 6. Each storage compartment can accommodate one item W. These storage compartments (transfer target locations 6) are arranged in the X and Y directions. The storage rack 9 is located on the grid-like path 18 side (second side Y2 in the Y direction) relative to the circular path 5 in the travel path 2. The storage compartments are located in the area of ​​the grid-like path 18 enclosed by the Y-direction path 3 and the X-direction path 4. One side of the storage compartment in the X direction is an entrance / exit for loading and unloading items W. Each storage compartment is arranged so that its entrance / exit faces the Y-direction path 3 side (transfer position 7 side). In the example of Figures 1 and 2, a group of three storage compartments (transfer target locations 6) arranged in the Y direction is called a storage compartment group, and multiple storage compartment groups are arranged. These storage compartment groups are arranged in groups of two or four in the X direction. The transport vehicle 10 then transfers the items W to two storage compartments of the storage shelf 9, which are aligned in the shelf depth direction (X direction), at the transfer position 7. In this example, the storage shelf 9 has a so-called double-deep structure, and the transfer device 14 of the transport vehicle 10 is configured to transfer items W to two storage compartments aligned in the X direction. In this example, the guide rails that guide the transport vehicle 10 are supported by the pillars and rails that make up the storage compartments. Alternatively, a chute may be provided instead of multiple storage compartments. In this case, the transfer target location 6 becomes the chute. In this case, the transport vehicle 10 can be configured to load the items W into the chute at the transfer position 7.

[0020] In the example shown in Figure 1, the transport equipment 1 is equipped with an loading / unloading section 8 for loading and unloading goods W between the inside and outside of the equipment. Here, the loading / unloading section 8 is a conveyor. Multiple loading / unloading sections 8 are arranged to correspond to the ends of the first Y1 side in the Y direction of each of the multiple Y-direction paths 3. The multiple loading / unloading sections 8 are also arranged on the first Y1 side in the Y direction with respect to the grid-shaped path 18, with the circular path 5 in between. The transport vehicle 10 can transfer goods W to the transfer target location 6 (storage section) as well as to each loading / unloading section 8. Note that Figure 1 shows only a portion of the multiple goods W stored in the storage section. In Figures 4 to 7, the description of the goods W stored in the storage section is omitted.

[0021] In this embodiment, each of the multiple transport vehicles 10 can be mainly classified into: a transport vehicle 10 that has received goods W from the loading / unloading section 8 and is moving toward a predetermined transfer target location 6 (loading transport vehicle 10a); a transport vehicle 10 that has received goods W from a predetermined transfer target location 6 and is moving toward the loading / unloading section 8 (loading transport vehicle 10b); a transport vehicle 10 that has received goods W from a predetermined transfer target location 6 and is moving toward another transfer target location 6 (shelf transport vehicle 10c); and a transport vehicle 10 that is moving without transporting goods W (empty transport vehicle 10d).

[0022] In this embodiment, the control system 100 includes the control device H and control unit 12 described above. In this example, the control device H comprises a determination unit 15, a calculation unit 16, and a storage unit 17. The storage unit 17 stores information about the multiple transport vehicles 10 (for example, the model of each transport vehicle 10), map information showing the travel route 2, and information showing the location of each storage unit (transfer target location 6). The storage unit 17 also stores information about the status of each storage unit (whether or not an item W is stored in it). The information about the status of the storage unit is updated each time an item is transferred by the transport vehicle 10.

[0023] The control device H controls each of the multiple transport vehicles 10 to transport the goods W. Specifically, the control device H transmits command information to the control unit 12 of each transport vehicle 10. Each transport vehicle 10 travels along the travel path 2 and transports the goods W according to the command information. The command information includes at least the destination of the transport vehicle 10, the transfer operation to be performed at the destination (receiving and handing over the goods W, etc.), and information about the route to the destination.

[0024] In this example, the control device H manages the position of each transport vehicle 10 by dividing the travel path 2 (grid-shaped path 18, circular path 5) into multiple zones. As shown by the dashed lines in Figure 1, these zones include intersection zones where the Y-direction path 3 and the X-direction path 4 intersect, and adjacent zones adjacent to the intersection zones. Each of the Y-direction path 3 and the X-direction path 4 is divided into multiple intersection zones and adjacent zones. The control device H manages each zone (intersection zone and adjacent zone) so that only one transport vehicle 10 can enter at a time (i.e., only one transport vehicle 10 can exist in each zone). In the example in Figure 2, multiple transfer positions 7 are set in one adjacent zone of the Y-direction path 3. As for the destinations of the transport vehicles 10 as described above, in addition to the transfer positions 7 set within the adjacent zones, adjacent zones and intersection zones where no transfer positions 7 are set are also included. In the example shown in Figure 1, the adjacent zones include a zone set between two intersection zones aligned in the X or Y direction, a zone corresponding to the loading / unloading section 8, and a zone adjacent to multiple storage sections (transfer target locations 6) that is also a dead end. In this example, each zone is equipped with a detectable section (one-dimensional code, two-dimensional code, etc.) that can be detected by the transport vehicle 10.

[0025] When the control device H's calculation unit 16 sets the final destination of the transport vehicle 10 (for example, a predetermined transfer position 7), it sets the route that the transport vehicle 10 should travel from its current position (the zone in which the transport vehicle 10 is located) to the final destination. The calculation unit 16 extracts multiple candidate routes from the current position to the final destination and calculates the cost of each candidate route. Preferably, the cost calculation is based on, for example, the cost set for a link that connects two intersections (nodes) (link cost), or the cost set for the operation of the traveling device 13 to move between the rail along the Y-direction route 3 and the rail along the X-direction route 4 (for example, the wheel switching operation). The control device H then selects the route with the lowest cost among the multiple candidate routes as the set route (route to the destination) and controls the transport vehicle 10 to travel along the set route. The method by which the control device H selects the optimal set route can be changed as appropriate.

[0026] In this embodiment, the control system 100 executes a first deadlock resolution process when a deadlock occurs in the travel path 2, where multiple transport vehicles 10 moving toward their respective destinations obstruct each other's movement and stop. This first deadlock resolution process involves designating each of the multiple transport vehicles 10 causing the deadlock as a factor transport vehicle 11 and resolving the deadlock by changing the destination of some of the factor transport vehicles 11 from their original destinations. If this process fails to resolve the deadlock, the control system 100 executes a second deadlock resolution process, which involves moving all factor transport vehicles 11 toward the circular path 5 and making them circle the circular path 5, and then moving each of the factor transport vehicles 11 on the circular path 5 toward their original destinations.

[0027] In this embodiment, as shown in Figure 8, the control system 100, in the first deadlock resolution process (S02 to S06), sequentially selects one factor transport vehicle 11 from all factor transport vehicles 11 as the target transport vehicle 11a, and determines whether the deadlock state is resolved by changing the destination of the target transport vehicle 11a from the original destination to another destination. The control system 100 then moves the target transport vehicle 11a, which it has determined that the deadlock state has been resolved, toward the other destination. In this example, as shown in Figure 8, the control device H (determination unit 15) determines whether a deadlock has occurred in the travel path 2 (here, the grid-shaped path 18) (S01). If the control device H determines that a deadlock has occurred (S01: Yes), it executes a sequential selection process (S02). Here, in the sequential selection process, the determination unit 15 sequentially selects one factor transport vehicle 11 from all factor transport vehicles 11 as the target transport vehicle 11a. Here, among the multiple factor transport vehicles 11, priority is set in the order of empty transport vehicle 10d, receiving transport vehicle 10a, shelf transport vehicle 10c, and outbound transport vehicle 10b. The determination unit 15 selects the target transport vehicle 11a according to the above priority. For example, if there is no empty transport vehicle 10d as a factor transport vehicle 11, but there is a receiving transport vehicle 10a, the determination unit 15 selects the receiving transport vehicle 10a as the target transport vehicle 11a. Furthermore, the control device H can appropriately change the above priority according to the zone in which each factor transport vehicle 11 is located. For example, the priority of the factor transport vehicle 11 to be selected as the target transport vehicle 11a can be set in the order of intersection zone, zones other than intersections and cul-de-sacs, and cul-de-sac zone. Here, "cul-de-sac zone" refers to a zone that is a dead end in the grid-like path 18. In addition to the above, if a charging station for charging the transport vehicle 10 is located on the travel route 2, the transport vehicle 10 moving towards the charging station may also be considered, and the transport vehicle 10 in motion may also be considered to avoid a deadlock situation.

[0028] Next, the control device H executes a destination change process (S03) to determine whether the deadlock is resolved. Specifically, the determination unit 15 determines whether the deadlock is resolved by changing the destination of the empty transport vehicle 10d from the original destination to another destination. Specifically, the determination unit 15 determines whether the deadlock is resolved when at least a portion of the set route from the current zone onward is changed for the selected target transport vehicle 11a. Here, the original destination is the final destination of the transport vehicle 10 (for example, a predetermined transfer position 7). Then, in the destination change process, by changing a portion of the set route, the original destination and the set route from the changed zone onward are canceled. As a result, the destination of the target transport vehicle 11a is set to the changed zone instead of the original destination. In this example, the control device H changes the destination of the target transport vehicle 11a from the original destination to a zone adjacent to the current position zone, or to a zone adjacent across an intersection zone.

[0029] If the control device H determines that the deadlock state can be resolved by the destination change process (S04: Yes), it executes a resolution movement process (S05). In the resolution movement process, the control device H makes the target transport vehicle 11a travel toward the changed destination. After that, the control device H executes a first restart process (S06) to make each factor transport vehicle 11 travel toward the original destination. In the example in Figure 4, an empty transport vehicle 10d, an incoming transport vehicle 10a, and an outgoing transport vehicle 10b are positioned as factor transport vehicles 11 on either side of an intersection. At the intersection, each factor transport vehicle 11 is in a deadlock state, stopping and obstructing each other's movement. In the illustrated example, the empty transport vehicle 10d is positioned in a dead-end zone. Therefore, in the sequential selection process, the control device H would normally select the empty transport vehicle 10d as the target transport vehicle 11a, but instead selects the incoming transport vehicle 10a as the target transport vehicle 11a. Furthermore, in the destination change process, the control device H changes the destination of the target transport vehicle 11a (inbound transport vehicle 10a) from the original destination (dead-end zone) to the adjacent zone (dashed circle) set on the X-direction route 4. Then, in the clearing movement process, the control device H makes the target transport vehicle 11a travel toward the changed zone (the adjacent zone mentioned above). In the first restart process, the control device H makes the outbound transport vehicle 10b travel toward the predetermined loading / unloading section 8, which is the original destination, and also makes the empty transport vehicle 10d travel toward the predetermined storage section, which is the original destination. Note that the dashed arrows in Figure 4 indicate the paths taken by each factor transport vehicle 11 toward its original destination. Also, the solid arrows in Figure 4 indicate the paths taken by the target transport vehicle 11a toward its changed destination. The same applies to Figure 5.

[0030] In the example shown in Figure 5, multiple factor transport vehicles 11 are stopped on a path (Y-direction path 3 and X-direction path 4) surrounding multiple transfer target locations 6 (storage units), obstructing each other's movement and resulting in a deadlock. Here, in the sequential selection process, the control device H selects one of the multiple empty transport vehicles 10d (factor transport vehicles 11) as the target transport vehicle 11a. Then, in the destination change process, the control device H changes the destination of the target transport vehicle 11a (empty transport vehicle 10d) to a dead-end zone. In the illustrated example, multiple candidate locations are listed for the changed destination of the empty transport vehicle 10d (indicated by dashed circles). When there are multiple candidate locations for the changed destination, the control device H determines whether the deadlock will be resolved at each candidate location. Furthermore, if a deadlock is resolved at multiple candidate locations, it is preferable to set one of the multiple candidate locations as the new destination, depending on factors such as the distance to the original destination of the target transport vehicle 11a and the position of the other transport vehicles 10. After the resolution and movement process is executed, the control device H executes the first restart process and causes all the factor transport vehicles 11 to travel toward their respective original destinations. In addition, if, during the first deadlock resolution process, there is a transport vehicle 10 that is waiting (stopped) on the travel path 2 without transporting the item W, and that transport vehicle 10 is obstructing the movement of the factor transport vehicle 11, the control device H may appropriately move that transport vehicle 10 to, for example, a dead-end zone where no other transport vehicles 10 are present.

[0031] In this embodiment, if the control device H determines that the deadlock state cannot be resolved for the selected target transport vehicle 11a, it selects the next highest priority transport vehicle 10 as the target transport vehicle 11a. The determination unit 15 then determines whether or not the deadlock state can be resolved for the newly selected target transport vehicle 11a. The control device H performs the same determination for all factor transport vehicles 11. If the result is that the deadlock state cannot be resolved (S04: No), the control device H executes the second deadlock resolution process (S07-S09). Here, the conditions under which the control device H (determination unit 15) determines that the deadlock cannot be resolved for each factor transport vehicle 11 include not only the case where the deadlock state is maintained even by the destination change process, but also, for example, the case where the deadlock state is resolved but the period until the first restart process is executed is longer than the set period, or the case where, even if the deadlock state is resolved once, it is expected that a transport vehicle 10 other than the factor transport vehicle 11 will cause a deadlock state again.

[0032] In the second deadlock resolution process, the control system 100 prioritizes moving the factor transport vehicles 11 that are furthest from the circular route 5 to their respective initial destinations, among the multiple factor transport vehicles 11 on the circular route 5, toward their initial destinations. In this example, as shown in Figure 8, the control device H executes the circular route movement process (S07), the departure order determination process (S08), and the second restart process (S09) in the order described, as the second deadlock resolution process.

[0033] In the circular path movement process, the control device H moves multiple factor transport vehicles 11 in order of proximity to the circular path 5, and also causes these factor transport vehicles 11 to travel in a circular path 5. In this example, the control device H causes each factor transport vehicle 11 to travel toward the circular path 5 in order of the shortest path distance from the position of the factor transport vehicle 11 that is stopped due to a deadlock state. Note that the order in which each factor transport vehicle 11 travel toward the circular path 5 may be determined not only by the shortest path distance as described above, but also by considering the number of intersections included in the shortest path, etc.

[0034] In the example shown in Figure 6, multiple transport vehicles 10 are stopped on a path (Y-direction path 3 and X-direction path 4) surrounding multiple transfer target locations 6 (storage units), obstructing each other's movement. Also, at two intersections located on the second side Y2 of the Y-direction, among the multiple (four in this case) intersections included in the said path, multiple transport vehicles 10 are stopped, obstructing each other's movement. Here, the control device H considers the multiple transport vehicles 10 present on the path surrounding the multiple transfer target locations 6 as factor transport vehicles 11 and moves these factor transport vehicles 11 to the circular path 5. In the illustrated example, the six factor transport vehicles 11 are classified into three incoming transport vehicles 10a, one outgoing transport vehicle 10b, and two empty transport vehicles 10d. In the example shown in Figure 7, these six factor transport vehicles 11 are moving in a circular path 5.

[0035] In the departure order determination process, the control device H determines the departure order of multiple factor transport vehicles 11 heading from the circular route 5 to their initial destinations based on the distance from the circular route 5 to the initial destination of each factor transport vehicle 11. Here, the determination unit 15 determines the departure order of each factor transport vehicle 11 based on the shortest path from the circular route 5 to its initial destination. The calculation unit 16 extracts the shortest path from among multiple paths connecting the initial destination zone and any zone on the circular route 5 for each factor transport vehicle 11 and sets it as the shortest path. Therefore, as shown by the arrows extending along the Y-direction path 3 in Figure 7, the shortest path is the shortest path from among multiple paths connecting any of the multiple intersection zones on the side closer to the grid-like path 18 on the circular route 5 to the initial destination zone. As described above, the calculation unit 16 sets the path with the lowest cost among multiple candidate paths as the shortest path for each factor transport vehicle 11. The control device H then determines the departure order so that the transport vehicle 11, which has the shortest path from the circular route 5 to its initial destination, departs first. The control device H may also determine the departure order so that the transport vehicle 10, whose initial destination is a dead-end zone, departs preferentially.

[0036] In the second restart process, the control device H moves each factor transport vehicle 11 to its initial destination in the order determined in the departure order determination process. Here, if there are multiple factor transport vehicles 11 whose initial destination is the same zone, the control device H may, for example, prioritize moving the factor transport vehicle 11 that stops at one of the multiple transfer positions 7 located in the zone, on the side furthest from the circular path 5. Furthermore, for the outbound transport vehicle 10b whose initial destination is the loading / unloading section 8, the control device H moves it to the loading / unloading section 8 at its initial destination from the circular path 5 (in this case, the X-direction path 4 furthest from the grid-like path 18) as appropriate, regardless of the determined departure order. The control device H may further modify the departure order determined in the departure order determination process in the second restart process, depending on the status of other transport vehicles 10 moving along the grid-like path 18.

[0037] [Other Embodiments] (1) In the above embodiment, a plurality of transfer target locations 6 (storage sections) are arranged along the X and Y directions, and each transfer target location 6 is configured to allow loading and unloading of articles W between itself and the transport vehicle 10 on a transfer position 7 set in the Y direction path 3. However, the embodiment is not limited to this. For example, the plurality of transfer target locations 6 can be arranged in multiple stages in the vertical direction. In this case, the travel path 2 (Y direction path 3, X direction path 4) can also be arranged in multiple stages to correspond to each of the multiple stages of transfer target locations 6. Naturally, each transfer target location 6 may also be configured to allow loading and unloading of articles W between itself and the transport vehicle 10 on the X direction path 4.

[0038] (2) In the above embodiment, a configuration in which no transfer position 7 is set in the circulating path 5 was described as an example, but the system is not limited to this. Transfer position 7 may also be set in the circulating path 5. For example, transfer position 7 can be set in the X-direction path 4 on the side of the grid-like path 18 in the circulating path 5. In this case, it is preferable that the storage section adjacent to the X-direction path 4 is configured to allow the transfer of articles W in the Y direction.

[0039] (3) In the above embodiment, an example was described in which the circulating path 5 is configured to intersect with all Y-direction paths 3 included in the travel path 2, but the example is not limited to this. The circulating path 5 may be configured to intersect with some of all Y-direction paths 3 included in the travel path 2, for example. For example, the circulating path 5 may be configured to intersect only with the Y-direction path 3 that is furthest away in the X direction, and not with any other Y-direction paths 3 that are located further inward in the X direction.

[0040] (4) In the above embodiment, the control system 100 was described as having a configuration in which, in the second deadlock resolution process, the factor transport vehicles 11 on the circular route 5 are prioritized to move toward their respective initial destinations, starting with those that are farther away from the circular route 5. However, the system is not limited to this configuration. The control system 100 may also prioritize moving toward its respective initial destinations, starting with those that are closer to the circular route 5.

[0041] (5) In the above embodiment, the control system 100 was described as having a configuration in which it moves one target transport vehicle 11a that it has determined has been freed from the deadlock to another destination in the first deadlock resolution process, but it is not limited to this. The control system 100 can also be configured to move multiple target transport vehicles 11a that it has determined have been freed from the deadlock to another destination, thereby resolving the deadlock.

[0042] (6) The configurations disclosed in each of the embodiments described above can be applied in combination with configurations disclosed in other embodiments, as long as no inconsistencies arise. With regard to other configurations, the embodiments disclosed herein are merely illustrative in all respects. Therefore, various modifications can be made as appropriate, without departing from the spirit of this disclosure.

[0043] [Summary of the above embodiment] The following is a summary of the conveying equipment described above.

[0044] The conveying equipment according to the present disclosure is a conveying equipment including a plurality of carrier vehicles that travel along a traveling route to convey articles, and a control system that controls the plurality of carrier vehicles. With a specific direction along the horizontal plane being the X direction and a direction intersecting the X direction in a top-down view being the Y direction, the traveling route includes a plurality of Y-direction routes that are routes along the Y direction, a plurality of X-direction routes that are routes along the X direction and each of which intersects at least one of the Y-direction routes, and a circulation route constituted by a pair of the X-direction routes and a pair of the Y-direction routes. The control system, when a deadlock state occurs in which a plurality of the carrier vehicles moving toward their respective destinations in the traveling route impede each other's movement and stop, designates each of the plurality of carrier vehicles that is a cause of the deadlock state as a cause carrier vehicle, and when the deadlock state cannot be resolved by executing a first deadlock resolution process of changing the destinations of some of the plurality of cause carrier vehicles from their original destinations, moves all of the cause carrier vehicles toward the circulation route and makes them circulate along the circulation route, and then executes a second deadlock resolution process of moving each of the cause carrier vehicles in the circulation route toward the original destination.

[0045] According to this configuration, even when the deadlock state cannot be resolved by the first deadlock resolution process of changing the destinations of some of the plurality of cause carrier vehicles, the deadlock state can be surely resolved without performing complicated control processing on the carrier vehicles. Further, since each carrier vehicle is moved from the circulation route toward the destination point, the possibility of the deadlock state occurring again can be reduced. Thus, according to this configuration, while appropriately resolving the deadlock state, the carrier vehicles that were the cause of the deadlock state can be directed toward the destination.

[0046] Here, a plurality of transfer target locations are provided along the travel route. Taking the positions corresponding to each of the transfer target locations on the travel route as transfer positions, the transport vehicle is configured to transfer the article to and from the transfer target location at the transfer position. It is preferable that the transfer position is not set on the circular route.

[0047] According to this configuration, since there is no transport vehicle with the circular route as the destination, the possibility that the transport vehicle stops on the circular route can be reduced. Therefore, it is possible to reduce the possibility that a plurality of factor transport vehicles that are factors causing the deadlock state easily circulate on the circular route and that a deadlock state occurs on the circular route.

[0048] Also, it is preferable that the transfer position is set on the Y-direction route and the circular route is configured to intersect all the Y-direction routes included in the travel route.

[0049] According to this configuration, since the circular route intersects all the Y-direction routes, in the second deadlock resolution process, it becomes easier for a plurality of factor transport vehicles circulating on the circular route to head toward their respective initial destinations. Also, it is possible to reduce the possibility that a deadlock state occurs again in the route from the circular route to the initial destination of each factor transport vehicle.

[0050] Also, in the second deadlock resolution process, it is preferable that the control system preferentially moves the factor transport vehicles that are far from their respective initial destinations among the plurality of factor transport vehicles on the circular route toward the initial destinations.

[0051] According to this configuration, it is easy to increase the possibility of appropriately moving each factor transport vehicle from the circular route to the initial destination. Also, it is possible to reduce the possibility that a deadlock state occurs again due to the movement of these factor transport vehicles.

[0052] Furthermore, in the first deadlock resolution process, the control system preferably sequentially selects one of the factor transport vehicles as the target transport vehicle, changes the destination of the target transport vehicle from the original destination to another destination, determines whether the deadlock state is resolved, and moves the target transport vehicle for which it has been determined the deadlock state is resolved toward the other destination.

[0053] This configuration allows for minimizing the number of transport vehicles that need to be moved to a destination other than the original destination in order to resolve a deadlock, and also increases the likelihood that the deadlock will be resolved by the first deadlock resolution process.

[0054] The transport equipment relating to this disclosure only needs to be able to achieve at least one of the effects described above.

[0055] 1: Conveying equipment 2: Travel route 3: Y-direction route 4: X-direction route 5: Circular route 6: Transfer target location 7: Transfer position 10: Conveyor vehicle 11: Factor transport vehicle 11a: Target transport vehicle 100: Control system

Claims

1. A transport system comprising: a plurality of transport vehicles that travel along a travel path to transport goods; and a control system that controls the plurality of transport vehicles, wherein the X direction is defined as a specific direction along a horizontal plane, and the Y direction is defined as a direction that intersects the X direction in an up-down view, the travel path includes a plurality of Y-direction paths which are paths along the Y direction, a plurality of X-direction paths which are paths along the X direction and each intersects at least one of the Y-direction paths, and a circular path which is composed of a pair of the X-direction paths and a pair of the Y-direction paths, and the control system is In the aforementioned travel path, if a deadlock occurs where multiple transport vehicles moving toward their respective destinations obstruct each other's movement and stop, the first deadlock resolution process, which resolves the deadlock by changing the destination of some of the multiple transport vehicles that are causing the deadlock from their original destination, is performed, and if the deadlock cannot be resolved by this process, the second deadlock resolution process is performed, which moves all of the multiple transport vehicles toward the circular path and makes them circle the circular path, and then moves each of the multiple transport vehicles that are on the circular path toward their original destination.

2. The transport equipment according to claim 1, wherein a plurality of transfer target locations are provided along the travel path, and the transport vehicle is configured to transfer the articles between the transfer target locations at the transfer positions, with each of the positions corresponding to each of the transfer target locations along the travel path being designated as a transfer position, and no transfer positions are set along the circular path.

3. The transport equipment according to claim 2, wherein the transfer position is set in the Y-direction path, and the circular path is configured to intersect with all of the Y-direction paths included in the travel path.

4. The transport equipment according to any one of claims 1 to 3, wherein the control system, in the second deadlock resolution process, prioritizes moving the multiple factor transport vehicles on the circular path toward the initial destination, starting with those vehicles that are furthest from the circular path toward the initial destination.

5. The transport equipment according to any one of claims 1 to 3, wherein the control system, in the first deadlock resolution process, sequentially selects one of the factor transport vehicles as the target transport vehicle, determines whether the deadlock state is resolved by changing the destination of the target transport vehicle from the original destination to another destination, and moves the target transport vehicle for which it has been determined that the deadlock state is resolved toward the other destination.

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