Distribution warehouse control device

Abstract

To provide a distribution warehouse control device capable of reducing a calculation load when calculating a conveyance router for conveying an article.SOLUTION: A route calculation section 13 executes control taking into consideration lateral and vertical transfer of an article. The route calculation section 13 also can calculate an efficient conveyance route taking into consideration a balance in the number of times of lateral and vertical transfer. Additionally, the route calculation section 13 executes calculation to prohibit the vertical transfer of the article when a predetermined condition becomes valid and control to allow the vertical transfer of the article to be performed when the predetermined condition becomes invalid. Thus, the rote calculation section 13 enables the lateral transfer to be continuously performed without limitation depending on a situation. Accordingly, the route calculation section 13 can search the efficient conveyance route depending on the situation and reduce a calculation load when calculating the conveyance route for conveying the article.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a control device for a logistics warehouse. [Background technology]

[0002] Conventionally, as a logistics warehouse for storing items, for example, the one described in Patent Document 1 is known. This logistics warehouse carries in items through a transport lane and stores them in an automated warehouse. This logistics warehouse also transports and takes out the items stored in the automated warehouse at a predetermined timing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-81008 A Summary of the Invention [Problem to be solved by the invention]

[0004] In this case, a large number of items are stored in the automated warehouse. Therefore, when the control device receives and takes out an item, it is necessary to calculate an efficient transport route. However, there is a problem in that the calculation load for calculating such a transport route is enormous.

[0005] Therefore, an object of the present invention is to provide a control device for a logistics warehouse that can reduce the calculation load when calculating a transport route for transporting an item. [Means for solving the problem]

[0006] A logistics warehouse control device according to one embodiment of the present invention is a logistics warehouse control device equipped with an automated warehouse for storing items, a transport lane for transporting a number of lined up items, and a transport machine provided between the transport lane and the automated warehouse, and includes an item information acquisition unit that acquires item information indicating an initial state and a completed state of the item's movement when the item moves in the order of the transport lane, the transport machine, and the automated warehouse, a route calculation unit that calculates transport route information from the item information so as to satisfy a reference logical formula based on constraint conditions, and an operation control unit that controls the transport operation of the logistics warehouse based on the transport route information, wherein the transport machine is a vertical transport machine that performs vertical transport by moving items horizontally while alternately raising and lowering a number of adjacent transport boxes, and the route calculation unit calculates to perform control that takes into account the horizontal movement of the items and the vertical movement of the items, and control that restricts the vertical movement of the items when specific conditions are satisfied.

[0007] In the control device for the logistics warehouse, the item information acquisition unit acquires item information indicating an initial state and a completed state of the movement of the item when the item moves in the order of the conveying lane, the conveying machine, and the automated warehouse, or when the item moves in the order of the automated warehouse, the conveying machine, and the conveying lane. The path calculation unit calculates conveying path information from the item information so as to satisfy a reference logical formula based on a constraint condition. In this case, the path calculation unit can calculate what conveying path the item should take between the initial state of the movement of the item and the completed state of the item. At this time, the path calculation unit calculates the reference logical formula so as to satisfy the reference logical formula based on the constraint condition, and can easily eliminate operations that are restricted in the conveying path by calculating the reference logical formula. As a result, the path calculation unit can calculate an appropriate conveying path with a small calculation load. The path calculation unit also performs control that takes into account the lateral movement of the item and the vertical movement of the item. As a result, the path calculation unit can calculate an efficient conveying path by considering the balance between the number of lateral movements and the number of vertical movements. Furthermore, the path calculation unit calculates to control the vertical movement of the article when a specific condition is satisfied. This allows the path calculation unit to continuously perform horizontal movement without restriction depending on the situation. Therefore, the path calculation unit can search for an efficient transport path depending on the situation. As a result, the calculation load when calculating a transport path for transporting an article can be reduced.

[0008] The path calculation unit may apply, to the leading item in the series, a formula indicating that the item on the entrance side will be on the entrance side transport shelf in the next phase or will remain lined up at the entrance side as it is, as a reference theoretical formula indicating the movement constraint of the item on the entrance side. In this case, it becomes possible to use the conventional constraint "Formula (24)" described later as it is.

[0009] The route calculation unit may define the acquired multiple transport route information as a sufficiency maximization problem and search for transport route information that minimizes the lateral cost of the item. In this case, the route calculation unit can adopt a transport route that can move the item most efficiently based on the lateral movement cost of the item. Effect of the Invention

[0010] According to the present invention, it is possible to reduce the calculation load when calculating a transport path for transporting an article. [Brief description of the drawings]

[0011] [Figure 1] 1 is a schematic side view showing a logistics warehouse equipped with a control device according to an embodiment of the present invention. [Diagram 2] 1 is a schematic diagram showing a configuration of a logistics warehouse according to an embodiment of the present invention; [Diagram 3] This is a diagram showing a model of a logistics warehouse. [Figure 4] FIG. 2 is a block diagram of a control device according to the present embodiment. [Diagram 5] This is a diagram showing a model of a logistics warehouse. [Figure 6] This is a diagram showing a model of a logistics warehouse. [Figure 7] FIG. 11 is a diagram illustrating the specific content of a logical expression. [Figure 8] FIG. 11 is a diagram illustrating the specific content of a logical expression. [Figure 9] FIG. 11 is a diagram illustrating the specific content of a logical expression. [Figure 10] (a) is a diagram showing the relationship between phases and movement directions, and (b) is a diagram modeling a logistics warehouse. [Figure 11] 1A is a diagram illustrating the specific content of a logical expression, and 1B and 1C are diagrams modeling a logistics warehouse. [Figure 12] 1A is a diagram illustrating the specific content of a logical expression, and 1B and 1C are diagrams modeling a logistics warehouse. [Figure 13] This is a diagram showing a model of a logistics warehouse. [Figure 14] 1A is a diagram illustrating the specific content of a logical expression, and 1B and 1C are diagrams modeling a logistics warehouse. [Figure 15] This is a diagram showing a model of a logistics warehouse. [Figure 16] 1A is a diagram illustrating the specific content of a logical expression, and 1B and 1C are diagrams modeling a logistics warehouse. [Figure 17] 1A is a diagram illustrating the specific content of a logical expression, and 1B and 1C are diagrams modeling a logistics warehouse. [Figure 18] 1A is a diagram illustrating the specific content of a logical expression, and 1B and 1C are diagrams modeling a logistics warehouse. [Figure 19] This is a diagram showing a model of a logistics warehouse. [Figure 20] This is a diagram showing a model of a logistics warehouse. [Figure 21] This is a diagram showing a model of a logistics warehouse. [Figure 22] FIG. 11 is a diagram illustrating the specific content of a logical expression. [Figure 23] FIG. 11 is a diagram illustrating the specific content of a logical expression. [Figure 24] FIG. 11 is a diagram illustrating the specific content of a logical expression. [Diagram 25] This is a diagram showing a model of a logistics warehouse. [Figure 26] This is a diagram showing a model of a logistics warehouse. [Figure 27] FIG. 11 is a diagram illustrating the specific content of a logical expression. [Figure 28] This is a diagram showing a model of a logistics warehouse. [Figure 29] FIG. 11 is a diagram illustrating the specific content of a logical expression. [Diagram 30] 4 is a flowchart showing the processing contents of the control device. [Diagram 31] FIG. 4 is a diagram showing an operation pattern of the conveyor. [Diagram 32] This is a diagram showing a model of a logistics warehouse. [Diagram 33] This is a diagram showing a model of a logistics warehouse. [Diagram 34] This is a diagram showing a model of a logistics warehouse. [Diagram 35] FIG. 13 is a diagram showing patterns for bundling items. [Diagram 36] FIG. 13 is a diagram showing patterns for bundling items. [Figure 37] FIG. 4 is a diagram showing an operation pattern of the conveyor. [Figure 38] This is a diagram showing a model of a logistics warehouse. [Figure 39] This is a diagram showing a model of a logistics warehouse. [Diagram 40] This is a diagram showing a model of a logistics warehouse. [Diagram 41] This is a diagram showing a model of a logistics warehouse. [Diagram 42] This is a diagram showing a model of a logistics warehouse. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

[0013] FIG. 1 is a schematic side view showing a logistics warehouse 1 equipped with a control device according to an embodiment of the present invention. As shown in FIG. 1, the logistics warehouse 1 is a system that receives and stores a plurality of items 150, and can retrieve items to be retrieved from among the stored items 150. The logistics warehouse 1 includes an automated warehouse 100, an outgoing elevator 104 (conveyor), an incoming elevator 105 (conveyor), an outgoing lane 121 (conveyor lane), and an incoming lane 21 (conveyor lane). The automated warehouse 100 is a warehouse that stores the items 150. The automated warehouse 100 includes a warehouse main body 101, an outgoing transfer passage 102, and an incoming transfer passage 103. The warehouse main body 101 has a plurality of shelves 110. The shelves 110 extend from one end of the warehouse main body 101 to the other end. In the shelf 110, the transfer device 111 transfers the goods from the entrance path to the exit path. The entrance transfer passage 103 is provided at one end of the warehouse main body 101, and is a mechanism for entering the goods 150 to each shelf 110. The exit transfer passage 102 is provided at the other end of the warehouse main body 101, and is a mechanism for removing the goods 150 from each shelf 110. The entrance elevator 105 raises and lowers the goods 150 entering from the entrance lane 21, and supplies the goods 150 to the entrance transfer passage 103 of the stage corresponding to the desired shelf 110. The exit elevator 104 receives the goods 150 to be removed from the shelf 110 and the exit transfer passage 102, and raises and lowers the goods 150 to an exit port (not shown). The goods 150 removed from the exit elevator 104 are transported to the exit lane 121.

[0014] FIG. 2 is a schematic diagram showing the configuration of a logistics warehouse 1 equipped with a control device 10 according to an embodiment of the present invention. In the following description, the receiving elevator 105 and the outgoing elevator 104 may be simply referred to as the "conveyor 22". FIG. 2 shows the configuration of the receiving side of the logistics warehouse 1. The outgoing side of the logistics warehouse 1 has the same configuration as the receiving side except that the flow of the goods 150 flows through the automated warehouse 100, the conveyor 22 (outgoing elevator 104), and the outgoing lane 121, so the description will be omitted. As shown in FIG. 2, the logistics warehouse 1 includes a conveyor system 2 that conveys the goods 150 and a control device 10 that controls the conveyor system 2. The conveyor system 2 includes a receiving lane 21, a conveyor 22, and a conveyor 23 of the automated warehouse 100. Of these, the conveyor 22 is a device that constitutes the above-mentioned receiving elevator 105. The receiving lane 21 is a device that conveys the goods 150 horizontally and transfers them to the conveyor 22. The storage lane 21 is provided for a predetermined stage of the conveyor 22. The conveyor 23 is a device that receives articles from the conveyor 22 and transports them horizontally on each floor of the automated warehouse 100. The conveyor 23 is provided on each floor (the fourth floor in this example) of the storage connecting passage 103.

[0015] The conveying machine 22 is equipped with a horizontal movement means (e.g., a conveyor) and a vertical movement means, and is a device that moves the goods 150 in the vertical and horizontal directions. Each of the goods 150 to be stored is linked to a destination floor to which it is to be transported. As a result, the conveying machine 22 moves each of the goods 150 to the destination floor in the storing walkway 103. In the figure, the number "n" is attached to goods 150 whose destination is the "nth floor". This is the same in the subsequent figures. In the following explanation, goods 150 whose destination is the nth floor may be referred to as "goods to the nth floor".

[0016] The conveyor 22 is a vertical conveyor that performs vertical conveyance by moving the article 150 in a horizontal direction (sideways) while alternately raising and lowering the adjacent conveyor boxes 22a. The conveyor 22 is an alternating-operation lifting device, and has a conveyor shelf 22A on the storage lane 21 side and a conveyor shelf 22B on the conveyor 23 side. The conveyor shelves 22A and 22B each have a storage area CE of "the number of floors of the automated warehouse + one floor". And, they have consecutive conveyor boxes 22a in the number of stages (four stages in this case) of "the number of floors of the automated warehouse". The consecutive conveyor boxes 22a move up and down at the same time. When the consecutive conveyor boxes 22a move downward, each conveyor box 22a is arranged in the storage area CE of the first stage to the fourth stage from the bottom. When the consecutive conveyor boxes 22a move upward, each conveyor box 22a is arranged in the storage area CE of the second stage to the fifth stage from the bottom. In the following description, when the number of stages is simply mentioned, it refers to the number of stages counted from the bottom unless otherwise noted. The transport boxes 22a on the transport shelf 22A and the transport boxes 22a on the transport shelf 22B move up and down alternately. That is, when the transport box 22a on the transport shelf 22A moves upward, the transport box 22a on the transport shelf 22B moves downward. This allows the item 150 on the transport shelf 22A to be raised by one stage (see operation M1). When the transport box 22a on the transport shelf 22A moves downward, the transport box 22a on the transport shelf 22B moves upward. This allows the item 150 on the transport shelf 22B to be raised by one stage. In addition, the item 150 can be moved horizontally between the transport box 22a on the transport shelf 22A and the transport box 22a on the transport shelf 22B at the same stage, and the item 150 can be handed over and received between them (see operation M2). Also, the article 150 can be delivered from the transport box 22a on the transport shelf 22B to the conveyor 23 on the destination floor (see operation M3).

[0017] In this embodiment, an input lane 21 is provided for the second storage area CE from the bottom, and four conveyors 23 are provided for the first to fourth storage areas CE from the bottom. Note that the locations indicated as "S1" and "S2" in the storage area CE in Fig. 2 are spaces provided for the lifting and lowering of the transport shelves 22A and 22B. However, the positional relationship between the storage area CE, the input lane 21, and the conveyors 23 is not particularly limited, and may be set appropriately depending on the configuration of the logistics warehouse 1.

[0018] In the following description, the logistics warehouse 1 may be modeled as shown in FIG. 3. The transport box 22a of the transport machine 22 is shown as a single rectangle. Each item 150 can move simultaneously in the horizontal direction unless there is an obstruction. As for vertical movement, the item 150 in the transport machine 22 cannot move while the transport shelf of the transport machine 22 is moving vertically. During the vertical movement of the transport machine 22, the storage lane 21 and the conveyor 23 can move horizontally. In the following description, the transport shelf 22A may be referred to as the "right (R) transport shelf" and the transport shelf 22B may be referred to as the "left (L) transport shelf". The state in which the left transport shelf 22B is raised as shown in FIG. 3(a) may be referred to as the "left transport shelf raised state", and the state in which the right transport shelf 22A is raised as shown in FIG. 3(b) may be referred to as the "right transport shelf raised state". Furthermore, each transport box 22a on the transport shelves 22A and 22B is assigned an identification number, such as "0, 1, 2, 3," in order from the bottom up. In the drawing, the identification number is indicated by a number enclosed in a circle on the transport box 22a.

[0019] Next, a block configuration of the control device 10 will be described with reference to FIG. 4. FIG. 4 is a block configuration diagram of the control device 10 according to this embodiment. The control device 10 is a unit that controls the conveying system 2. The control device 10 includes an ECU [Electronic Control Unit] that performs overall management of the logistics warehouse 1. The ECU is an electronic control unit that includes a CPU [Central Processing Unit], a ROM [Read Only Memory], a RAM [Random Access Memory], and a communication circuit such as a CAN [Controller Area Network]. For example, the ECU loads a program stored in the ROM into the RAM and executes the program loaded into the RAM with the CPU to realize various functions. The control device 10 includes an operation control unit 11, an item information acquisition unit 12, and a route calculation unit 13.

[0020] The operation control unit 11 is a unit that controls the transport operation of the logistics warehouse 1 so that each item 150 is transported based on the transport route calculated by the route calculation unit 13. The operation control unit 11 controls the transport operation by sending a control signal to the transport system 2. The operation control unit 11 operates each drive unit by sending a control signal to each drive unit of the storage lane 21, the transport machine 22, and the conveyor 23 of the transport system 2.

[0021] The item information acquisition unit 12 acquires item information indicating an initial movement state and a completed movement state of the item 150 when the item 150 moves in the order of the storage lane 21, the conveyor 22, and the automated warehouse 100, or when the item moves in the order of the automated warehouse 100, the conveyor 22, and the outgoing lane 121. The initial movement state is a state in which the item 150 to be transported is present in the storage lane 21, as shown in FIG. 5(a). The completed movement state is a state in which all of the items 150 to be transported have been transported to the automated warehouse 100, as shown in FIG. 5(b). The item information includes information such as the floor number of the destination of the item 150 present in the storage lane 21 at the time of storage, the number of items 150 for each floor, and the order of storage. The item information also includes information such as the number of items 150 to be taken out from which floor of the automated warehouse 100, and the order of their outgoing.

[0022] The route calculation unit 13 is a unit that calculates transport route information from the item state information so as to satisfy a reference logical formula based on constraint conditions. The route calculation unit 13 searches for a transport route for each item 150 in the transport system 2. Here, between the initial movement state and the movement completion state shown in FIG. 5(a), the transport system 2 simultaneously moves each item 150 horizontally and vertically, and transports each item 150 to its destination by combining each operation. At this time, the control device 10 moves the items 150 under the operational restrictions of the transport system 2 so that the items 150 do not interfere with each other and can be sorted quickly. At this time, the route calculation unit 13 calculates what route each item 150 will take in the transport system 2 to reach the destination. The route calculation unit 13 searches for a route for each item 150 in a predetermined number of items 150 using a shortest route search method or the like, with each part of the transport system 2 as a search node.

[0023] Here, the path calculation unit 13 defines the constraint conditions as a satisfiability problem (SAT problem). The SAT problem is a problem of determining whether there exists a value assignment to a proposition variable that makes a logical formula including a proposition variable true. The SAT problem is to solve a decision problem, that is, to find whether there is a solution that satisfies the constraints. For example, in response to the question "Can all the items 150 arrive at the destination floor with five or fewer up and down movements of the transport shelves 22A and 22B of the transport machine 22?", the answer is "Yes. The specific schedule is...". The reference logical formula includes a movement constraint regarding the movement of the items 150, an initial constraint regarding the initial state of the items, and an arrival constraint regarding the arrival of the items 150 at the destination.

[0024] In addition, the route calculation unit 13 defines the acquired multiple transport route information as a Maximum Satisfiability Problem (MaxSAT problem). The MaxSAT problem is a problem of finding a variable ratio that maximizes the number of satisfied clauses for a set of clauses given as input. The MaxSAT problem is to solve an optimization problem, that is, to find an optimal solution that satisfies constraints. For example, for the question, "What is the shortest time for all 150 items to arrive at the destination floor?", the answer is "10 seconds. The specific schedule is ~." The route calculation unit 13 calculates at least one of a solution that satisfies all hard clauses and maximizes the sum of the weights of the satisfied soft clauses, and a solution that satisfies all hard clauses and minimizes the sum of the weights of the unsatisfied soft clauses. A hard clause is a clause that must be satisfied. A soft clause is a clause that should be satisfied as much as possible, and the degree of satisfaction is represented by a weight (a positive integer).

[0025] [Preparation for explanation] First, before explaining the constraints of the SAT problem and the MaxSAT problem, we will explain the terminology. From now on, we will explain it as a common point for the SAT problem and the MaxSAT problem. A "constraint" is expressed as a set of clauses. A "clause" is the logical sum of literals, and is shown in the following formula (1). A "literal" is a logical variable or its negation, and is shown in formula (2). A "variable" takes the value of "True" or "False", and True may be considered as "1" and False as "0". In this specification, formulas (3), (4), and (5) are used as substitutes for clauses. Formula (3) can also be shown as formula (6).

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[0026] Equation (3) and equation (6) are "a1 to a m If all of the above is true, then c1 to c n must be true." Using equations (3) and (6), for example, we can show that "If an item is in XX on the right-hand transport shelf (representing each a), then in the next state, it will either stay there or be in YY on the left-hand transport shelf (representing each c)." Equation (4) is "The number of items from l1 to l n Of l1 to l, at most one is True. n If all of the above are False, the left side of equation (4) will be "0". In other words, the left side of equation (4) will be "1" or "0". Using equation (4), it is possible to express, for example, that "Each transport box (each transport box represents l) on the transport shelf can contain at most one item." This means that the same item 150 cannot be present in the same transport box 22a at the same time. If a certain item 150 does not fit into any transport box 22a, the left side of equation (4) will be "0". Equation (5) expresses "The number of items from l1 to l nis interpreted as "exactly one of these is True." Using formula (5), it is possible to express, for example, "a certain item is always present in either the storage lane, the transport shelf, or the destination floor (each location represents l)." In the following explanation, when the constraint conditions are explained, simply referring to "entrance" is understood to mean storage lane 21. Furthermore, when the constraint conditions are explained, simply referring to "item" is understood to mean item 150.

[0027] [Steps and Phases] In this description, the initial state of the logistics warehouse 1 is a state in which the left transport shelf 22B is raised and the right transport shelf 22A is lowered, as shown in FIG. 3(a). The route calculation unit 13 performs calculations by considering three-phase operations that enable the lateral movement of the article 150 and one lifting and lowering operation of the transport machine 22 as one step. The route calculation unit 13 performs the operation repeatedly, with the operation of "three phases and one step" as the basic operation. As shown in FIG. 6, the article 150 can move horizontally (moving horizontally) to the next position in each phase. Note that the number of articles that are horizontally moved in one phase is not particularly limited, and no article may be moved horizontally at all. Note that the route calculation unit 13 may omit phases in which no horizontal movement is performed without allocating time when calculating the transport route in the subsequent calculation. When the three phases are completed, the step is switched. At the timing of the step switching, the transport shelves 22A and 22B are switched between the "left transport shelf raised state (see FIG. 3(a))" and the "right transport shelf raised state (see FIG. 3(b))". The inventors of the present application discovered that, while the movement of the article 150 does not progress even if the switching operations of the transport shelves 22A and 22B occur continuously, the movement of the article 150 progresses even if the horizontal movement of the article 150 is performed continuously. The inventors of the present application also adopted 3, which is an appropriate number for the number of phases in one step, because the movement of the article 150 does not progress even if the horizontal movement is performed four or more times continuously (with exceptions). The reason for the number of phases being 3 is that the horizontal movement during the period when the vertical movement in the transport shelves 22A and 22B is not performed (during one step), is a maximum of one right movement and a maximum of two left movements (with exceptions), so the total value is 3.

[0028] The variables for indicating steps and phases are explained. (7) shown below is a variable indicating that "the i-th item is lined up at the entrance in phase p of step t". (8) is a variable indicating that "the i-th item is at the destination floor in phase p of step t". (9) is a variable indicating that "the i-th item is in transport box j on the left transport shelf in phase p of step t". Note that "j" for identifying the transport box 22a is an identification number shown in a circle in FIG. 3. (10) is a variable indicating that "the i-th item is in transport box j on the right transport shelf in phase p of step t". "Phase p of step t" may be abbreviated as "(t,p)" indicating time and used in the following explanation. Note that the index is "0 origin". Also, the start is "step 0, phase 0". Therefore, (t,p) transitions as "(0,0) → (0,1) → (0,2) → (1,0) → (1,1) → ...". At the timing of the change in step t, the transport shelves 22A and 22B are switched. If step t is an even number, it indicates that the left transport shelf is in the raised state (see FIG. 3(a)), and if step t is an odd number, it indicates that the right transport shelf is in the raised state (see FIG. 3(b)). In order to express the transition of (t, p), the variable shown in (11) is adopted. (11) is a variable that returns the next step and phase of (t, p). Specifically, the variable (11) indicates the contents shown in FIG. 7(a).

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[0029] [Entrance constraints] The constraint conditions related to the entrance (i.e., the storage lane 21) will be explained. The reference logical formula includes the logical formulas (12) and (13) indicating the entrance constraints as initial constraints related to the initial state. Equation (12) is interpreted as "if item i is lined up at the entrance at (t, p), it was lined up before that." Equation (13) is interpreted as "if item i is lined up at the entrance at (t, p), item i+1 is also lined up." The specific content of equation (12) is shown in FIG. 7(b). The specific content of equation (13) is shown in FIG. 7(c). Note that "M" means the maximum value of the up and down movement of the transport shelves 22A and 22B. The meaning of "M" will be the same in the following explanations.

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[0030] [Destination Floor Constraint] The constraint conditions related to the destination floor of the automated warehouse 100 will be described. The reference logical formula includes the logical formula of formula (14) indicating the destination floor constraint as an arrival constraint related to the arrival of the item at the destination floor (destination). Formula (14) is interpreted as "if item i arrives at the destination floor at (t, p), it will remain the same thereafter." The specific content of formula (14) is shown in FIG. 8(a).

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[0031] [Conveyor box constraints on transport shelves] The constraint conditions for transport boxes 22a on transport shelves 22A and 22B will now be described. The reference logical formula includes logical formulas (15) and (16) which indicate transport box constraints as movement constraints on the movement of items. Equation (15) is interpreted as "at (t, p), two or more items cannot be placed in transport box j on the left transport shelf." Equation (16) is interpreted as "two or more items cannot be placed in transport box j on the right transport shelf." Note that "N" refers to the number of items. The same applies to the subsequent logical formulas. Equation (17) indicates the range of values ​​that (t, p) can take.

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[0032] [Item existence constraint] We will now explain the constraint condition regarding the presence of an item somewhere in the transport system 2. The reference logical formula includes, as a movement constraint, the logical formula of equation (18) which indicates the presence constraint regarding the presence of an item while the item is moving. Equation (18) is interpreted as "at (t, p), item i is either lined up at the entrance, is in the transport shelf, or has reached the destination floor." Equation (19) indicates the range of values ​​that (t, p) can take.

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[0033] [Auxiliary function (cartridge position)] An auxiliary function is set that indicates the relationship between transport boxes 22a on transport shelves 22A and 22B. (20) shown below is an auxiliary function that indicates "a transport box on the left transport shelf that can be moved from transport box j on the right transport shelf". (21) shown below is an auxiliary function that indicates "a transport box on the right transport shelf that can be moved from transport box j on the left transport shelf". (22) shown below is an auxiliary function that indicates "a transport box on the left transport shelf that is stopped at the entrance floor at step t". (23) shown below is an auxiliary function that indicates "a transport box on the right transport shelf that is stopped at the entrance floor at step t".

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[0034] The specific content of the auxiliary function (20) is shown in FIG. 9(a). The specific content of the auxiliary function (21) is shown in FIG. 9(b). The specific content of the auxiliary function (22) is shown in FIG. 9(c). The specific content of the auxiliary function (23) is shown in FIG. 9(d). If the step t is an even number, the state is "left transport shelf raised state (see FIG. 3(a))". Therefore, the relationship between the transport box 20a on the right transport shelf 22A and the transport box 22a on the left transport shelf 22B is shown in FIG. 3(a). In addition, for the transport boxes 22a on the transport shelves 22A and 22B parked on the second floor, which is the entrance floor, as shown in FIG. 3(a), the right transport shelf 22A has "identification number 1" and the left transport shelf 22B has "identification number 0". If the step t is an odd number, the state is "right transport shelf raised state (see FIG. 3(b))". Therefore, the relationship between the transport box 20a on the right transport shelf 22A and the transport box 22a on the left transport shelf 22B is shown in Fig. 3(b). Also, for the transport boxes 22a on the transport shelves 22A and 22B parked on the second floor, which is the entrance floor, as shown in Fig. 3(b), the right transport shelf 22A has an "identification number 0" and the left transport shelf 22B has an "identification number 1."

[0035] Movement Constraint (Entrance) We will now explain the constraints on the movement of items when they are lined up at the entrance. The reference logical formula includes the logical formula (24) that indicates the movement constraint of items on the entrance side as a movement constraint. Equation (24) is interpreted as "if item i is lined up at the entrance at (t, p), then in the next phase next(t, p), it will be on the transport shelf on the right side or will remain lined up at the entrance." The specific content of equation (24) is shown in Figure 8(b).

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[0036] [Movement constraints (transport shelf)] The constraint conditions for the movement of an item when the item is on the transport shelves 22A and 22B will be described. Here, the basic conditions for the movement constraints of the transport shelves 22A and 22B will be described. Of the three phases, the conditions are set such that the item moves to the left in the first two phases and moves to the right in the last phase. The specific relationship between the phases and the movement directions is shown in FIG. 10(a). By setting such conditions, it is possible to eliminate an operation in which the item A on the transport shelf 22B and the item B on the transport shelf 22A are suddenly replaced in the next phase when the items A and B are moving horizontally, as shown in FIG. 10(b). The reference logical formula includes, as the movement constraints, the logical formulas of formulas (25) and (26) which indicate the movement constraints of the item placed in the immovable transport box on the right transport shelf 22A. Formula (25) is interpreted as "when the item i is in the transport box "0" on the right transport shelf at (t, p) where t is an even number, in the next phase next(t, p), it is in the same transport box "0". Equation (26) is interpreted as "When item i is in box "3" on the right-side transport shelf at (t, p) where t is an odd number, in the next phase next(t, p), it is in the same box "3". The specific contents of equations (25) and (26) are shown in FIG. 11(a). When t is an even number, the bottommost transport box 22a with "identification number 0" on the right-side transport shelf 22A is not adjacent to any other transport box 22a, the automated warehouse 100, or the storage lane 21 (see FIG. 11(b)). When t is an odd number, the topmost transport box 22a with "identification number 3" on the right-side transport shelf 22A is not adjacent to any other transport box 22a, the automated warehouse 100, or the storage lane 21 (see FIG. 11(c)). Therefore, the items placed in those transport boxes 22a with "identification numbers 1, 3" cannot be moved to any other location in the next phase and remain there.

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[0037] The reference logical formula includes, as a movement constraint, logical formulas (27) and (28) that indicate the movement constraint of the item placed in the transport box that can move leftward on the right transport shelf 22A other than the entrance floor. The formula (27) is interpreted as "item i in transport box j on the right transport shelf moves leftward or remains in the same transport box j when transitioning from (t, 0) to (t, 1)". The formula (28) is interpreted as "item i in transport box j on the right transport shelf remains in the same transport box j when transitioning from (t, 1) to (t, 2) or when transitioning from (t, 2) to (t + 1, 0)". The specific contents of the formulas (27) and (28) are shown in FIG. 12(a). When t is an even number, as shown in FIG. 12(b), the transport box 22a with "identification number 2, 3" on the right transport shelf 22A corresponds to the transport box 22a that can move leftward other than the second floor, which is the entrance floor. When t is an odd number, as shown in FIG. 12(c), the transport box 22a with the "identification numbers 1, 2" on the right transport shelf 22A corresponds to the transport box 22a that can move left to any floor other than the second floor, which is the entrance floor.

number

[0038] The reference logical formula includes, as the movement constraints, the logical formulas of formula (29), formula (30), and formula (31) which indicate the movement constraints of the item placed in the transport box stopped at the entrance floor of the right transport shelf 22A. Formula (29) is interpreted as "item i in transport box j on the right transport shelf moves to the left or remains in the same transport box j when transitioning from (t,0) to (t,1)". Formula (30) is interpreted as "item i in transport box j on the right transport shelf remains in the same transport box j when transitioning from (t,1) to (t,2) or from (t,2) to (t+1,0) if it was there immediately before." Equation (31) is interpreted as "when the item i in the transport box j on the right transport shelf transitions from (t,1) to (t,2) or from (t,2) to (t+1,0), if the item i was not there immediately before, it moves to the left or stays in the same transport box j." When t is an even number, as shown in FIG. 13(a), the transport box 22a with "identification number 1" on the right transport shelf 22A corresponds to the transport box 22a stopped on the second floor, which is the entrance floor. When t is an odd number, as shown in FIG. 12(b), the transport box 22a with "identification number 0" on the right transport shelf 22A corresponds to the transport box 22a stopped on the second floor, which is the entrance floor.

number

[0039] The reference logical formula includes, as a movement constraint, the logical formula of formula (32) which indicates the movement constraint of the item placed in the transport box on the left transport shelf 22B that cannot be moved. Formula (32) is interpreted as "When item i is in transport box "3" on the left transport shelf at (t, p) where t is an even number, in the next phase next(t, p), it is in the same transport box "3". The specific content of formula (32) is shown in FIG. 14(a). When t is an even number, the top transport box 22a with "identification number 3" on the left transport shelf 22B is not adjacent to any other transport box 22a, the automated warehouse 100, or the storage lane 21 (see FIG. 14(b)). Therefore, the item placed in the transport box 22a with "identification number 3" cannot be moved to any place in the next phase and remains there. When t is an odd number, there is no transport box 22a that cannot be moved on the left transport shelf 22B (see FIG. 14(c)).

number

[0040] The reference logical formula includes, as movement constraints, logical formulas (33), (34), and (35) that indicate movement constraints of an item placed in a transport box on the left transport shelf 22B at the destination floor. Equation (33) is interpreted as "item i in transport box j on the left transport shelf moves to the left or remains in the same transport box j when transitioning from (t,0) to (t,1)." Equation (34) is interpreted as "item i in transport box j on the left transport shelf remains in the same transport box j when transitioning from (t,1) to (t,2) or from (t,2) to (t+1,0) if it was there immediately before." Equation (35) is interpreted as "when the item i in the transport box j on the left transport shelf transitions from (t,1) to (t,2) or from (t,2) to (t+1,0), if the item i was not there immediately before, it moves to the left or stays in the same transport box j." When t is an even number, as shown in FIG. 15(a), the transport box 22a with "identification numbers 0,1,2" on the left transport shelf 22B corresponds to the transport box 22a stopped at the target floor. When t is an odd number, as shown in FIG. 15(b), the transport box 22a with "identification numbers 0,1,2,3" on the left transport shelf 22B corresponds to the transport box 22a stopped at the target floor.

number

[0041] The reference logical formula includes, as a movement constraint, the logical formula of formula (36) which indicates the movement constraint of the item placed in the transport box stopped at a floor other than the destination floor of the left transport shelf 22B. Formula (36) is interpreted as "item i in transport box j of the left transport shelf remains in the same transport box j when transitioning from (t, 0) to (t, 1) or when transitioning from (t, 1) to (t, 2)". The specific content of formula (36) is shown in FIG. 16(a). When t is an even number, as shown in FIG. 16(b), the transport box 22a with "identification number 0, 1, 2" of the left transport shelf 22B corresponds to the transport box 22a stopped at a floor other than the destination floor. When t is an odd number, as shown in FIG. 16(c), the transport box 22a with "identification number 0, 1, 2, 3" of the left transport shelf 22B corresponds to the transport box 22a stopped at a floor other than the destination floor.

number

[0042] The reference logical formula includes, as a movement constraint, the logical formula of formula (37) which indicates the movement constraint of an item placed in a transport box that is stopped at a floor that is not the destination floor of the left transport shelf 22B and cannot be moved to the right. Formula (37) is interpreted as "item i in transport box j of the left transport shelf remains in the same transport box j when transitioning from (t, 2) to (t+1, 0)". The specific content of formula (37) is shown in FIG. 17(a). When t is an even number, as shown in FIG. 17(b), there is no floor in the left transport shelf 22B that is not the destination floor and cannot be moved to the right. When t is an odd number, as shown in FIG. 17(c), the transport box 22a with "identification number 0" on the left transport shelf 22B corresponds to the transport box 22a that is not the destination floor and cannot be moved to the right.

number

[0043] The reference logical formula includes, as a movement constraint, logical formulas (38) and (39) which indicate the movement constraint of the item placed in the transport box that is stopped at a floor that is not the destination floor of the left transport shelf 22B, is allowed to move to the right, and is not the entrance floor. The formula (38) is interpreted as "item i in transport box j of the left transport shelf will stay in the same transport box j if it is not there in phase 0 when transitioning from (t, 2) to (t + 1, 0)". The formula (39) is interpreted as "item i in transport box j of the left transport shelf will move to the right or stay in the same transport box j if it is there in phase 0 when transitioning from (t, 2) to (t + 1, 0)". The specific contents of the formulas (38) and (39) are shown in FIG. 18(a). When t is an even number, as shown in Fig. 18(b), the transport box 22a with "identification numbers 1, 2" on the left transport shelf 22B corresponds to the transport box 22a that is not the destination floor, can move to the right, and is not the entrance floor. When t is an odd number, as shown in Fig. 18(c), the transport box 22a with "identification numbers 2, 3" on the left transport shelf 22B corresponds to the transport box 22a that is not the destination floor, can move to the right, and is not the entrance floor.

number

[0044] Here, (40) shown below is an auxiliary variable indicating that "an item is contained in the transport box j at the entrance floor of the right transport shelf (p=2)". Using this auxiliary variable, and based on De Morgan's law, the fact that an item is contained in the transport box 22a at the entrance floor 2 of the right transport shelf 22A is expressed by formulas (41) and (42). When t is an even number, as shown in FIG. 19(a), the transport box 22a with "identification number 1" on the right transport shelf 22A corresponds to the transport box 22a at the entrance floor. When t is an odd number, as shown in FIG. 19(b), the transport box 22a with "identification number 0" on the right transport shelf 22A corresponds to the transport box 22a at the entrance floor.

number

[0045] The reference logical formula includes, as a movement constraint, logical formulas (43), (44), and (45) that indicate the movement constraint of an item placed in a transport box that is a floor that is not the destination floor of the left transport shelf 22B, can be moved to the right, and is stopped at the entrance floor. Formula (43) is interpreted as "if item i in transport box j on the left transport shelf is not present in phase 0 when transitioning from (t, 2) to (t + 1, 0), it will remain in the same transport box j." Formula (44) is interpreted as "if item i in transport box j on the left transport shelf is present in phase 0 when transitioning from (t, 2) to (t + 1, 0), and the transport box to the right is empty, it will either move to the right or remain in the same transport box j." Equation (45) is interpreted as "When the item i in the transport box j on the left transport shelf is in phase 0 during the transition from (t, 2) to (t+1, 0), if there is something in the transport box to the right, it will stay in the same transport box j." When t is an even number, as shown in FIG. 20(a), the transport box 22a with "identification number 0" on the left transport shelf 22B corresponds to the transport box 22a that is not the destination floor, but can move to the right and is stopped at the entrance floor. When t is an odd number, as shown in FIG. 20(b), the transport box 22a with "identification number 1" on the left transport shelf 22B corresponds to the transport box 22a that is not the destination floor, but can move to the right and is stopped at the entrance floor.

number

[0046] [Initial and arrival constraints] Let us explain the initial constraint. (46) shown below indicates that "initially, all items are lined up at the entrance," so it is True. Let us explain the arrival constraint. (47) shown below indicates that "after M up and down movements of the transport rack, all items must have arrived at the destination floor," so it is True.

number

[0047] [When items bound for the second floor are consecutive] When articles having the same entrance floor and destination floor pass the conveyor 22 consecutively, four phases are required (for example, when there are two articles) to pass through the conveyor 22. For example, as shown in FIG. 21(a), the article in front can reach the destination floor, the second floor, by horizontal movement in three phases, but the article in the back cannot reach the destination floor without horizontal movement in four phases. In this way, in the three-phase one-step system, such passing through is not scheduled. Therefore, the route calculation unit 13 regards multiple consecutive articles as one article. As shown in FIG. 21(b), the route calculation unit 13 regards two articles as one article as indicated by "150B". In this case, "150B" can reach the destination floor by horizontal movement in three phases. The number of articles to be combined is not particularly limited, and three or more articles may be combined.

[0048] Movement Constraint (Entrance) The reference logical formula includes, as the movement constraints, the logical formulas of formula (48), formula (49), and formula (50) which indicate the movement constraints at the entrance. Formula (48) is interpreted as "item i at the entrance can be moved to the right-hand transport shelf only in phase 0." Formula (49) is interpreted as "item i at the entrance remains at the entrance in phase 1." Formula (50) is interpreted as "item i at the entrance remains at the entrance in phase 2."

number

[0049] Movement constraint (right delivery shelf) The reference logical formula includes logical formulas (51) and (52) that indicate the movement constraints on the transport box on the entrance floor of the right transport shelf as the movement constraints. The formula (51) is interpreted as "item i on the transport box on the entrance floor of the right transport shelf always moves to the left transport shelf when t is an even number and the transition is from (t, 1) to (t, 2)". The formula (51) is interpreted as "item i on the transport box on the entrance floor of the right transport shelf always moves to the left transport shelf when t is an odd number and the transition is from (t, 1) to (t, 2)". Note that there is "no constraint" when the transition is from (t, 0) to (t, 1) or from (t, 2) to (t+1, 0). When t is an even number, as shown in FIG. 19(a), the transport box 22a with "identification number 1" on the right transport shelf 22A corresponds to the transport box 22a on the entrance floor. When t is an odd number, as shown in FIG. 19(b), the transport box 22a with "identification number 0" on the right transport shelf 22A corresponds to the transport box 22a on the entrance floor.

number

[0050] Movement constraint (left delivery shelf) The reference logical formula includes logical formulas (53) and (54) that indicate the movement constraints of the transport box on the destination floor and entrance floor of the left transport shelf as the movement constraints. The formula (53) is interpreted as "item i of the transport box on the destination floor and entrance floor of the left transport shelf always moves to the left when t is an even number and transitions from (t, 2) to (t + 1, 0)". The formula (54) is interpreted as "item i of the transport box on the destination floor and entrance floor of the left transport shelf always moves to the left when t is an odd number and transitions from (t, 2) to (t + 1, 0)". Note that there is "no constraint" when transitioning from (t, 0) to (t, 1) or from (t, 1) to (t, 2). As shown in FIG. 20(a), the transport box 22a with "identification number 0" on the left transport shelf 22B corresponds to the transport box 22a stopped at the destination floor and entrance floor. When t is an odd number, as shown in FIG. 20(b), the transport box 22a with "identification number 1" on the left transport shelf 22B corresponds to the transport box 22a parked at the destination floor and the entrance floor.

number

[0051] [Optimal solution search possible with SAT] Next, we will explain the optimal solution search unique to SAT. M Let S be the set of constraints (clauses) obtained when M is given. M If there is a solution, it can be interpreted that all items can reach the destination floor within M up and down movements of the transport shelf. M If there is no solution, it can be interpreted as "all the items will not reach the destination floor within M up and down movements of the transport shelf." For example, "S0, S1, ... S m-1 " is "no solution", and "S m If “,…” has a solution, then “m” is the optimal value.

[0052] [MaxSAT] Next, the contents unique to MaxSAT will be explained. To explain MaxSAT, variables (55) and (56) are prepared. (55) shown below is a variable indicating that "all items have arrived at the destination floor in phase 0 of step t." (56) shown below is a variable indicating that "during the transition from (t,0) to (t,1) to (t,2) to (t+1,0), the items have made horizontal movements k+1 times." When the path calculation unit 13 calculates the MaxSAT problem, it also calculates the above-mentioned constraint conditions calculated as the SAT problem.

number

[0053] [Soft clauses and related hard clauses] The hard clauses related to the soft clauses will be explained. First, the variables in (55) above will be explained. (55) indicates the cost of the up and down movement of the transport shelves 22A and 22B, and "weight: 1" can be set. The logical formula shown in formula (57) holds for this variable. "N" means the number of items. The meaning of "N" will be the same in the following explanations. Formula (57) is interpreted as "All the items have arrived at the destination floor by phase 0 of step t." The specific content of formula (57) is shown in Figure 22(a).

number

[0054] We will explain the variable in (56) above. This variable is used in the negative form as shown in (58). (58) indicates the cost of horizontal movement of an item, and can be set to "weight: 1". Equation (59) is interpreted as "during the transition from (t, 0) to (t, 1) to (t, 2) to (t+1, 0), no horizontal movement of the item occurs."

number

[0055] Regarding horizontal movement from the entrance, formula (60) holds. Formula (60) can be interpreted as "if item i is lined up at the entrance at (t, 0) and is on the right-hand transport shelf at the next step (t+1, 0), the horizontal movement cost is 1." A specific example of formula (60) is shown in FIG. 22(b). When t is an even number, as shown in FIG. 19(a), transport box 22a with "identification number 1" on right-hand transport shelf 22A corresponds to transport box 22a through which items are moved from the entrance. When t is an odd number, as shown in FIG. 19(b), transport box 22a with "identification number 0" on right-hand transport shelf 22A corresponds to transport box 22a through which items are moved from the entrance.

number

[0056] Regarding horizontal movement from the entrance, formula (61) holds. Formula (61) is interpreted as "if item i is lined up at the entrance at (t, 0) and is on the left transport shelf at the next step (t+1, 0), the horizontal movement cost is 2." A specific example of formula (61) is shown in FIG. 23(a). When t is an even number, as shown in FIG. 20(a), the transport box 22a with "identification number 0" on the left transport shelf 22B corresponds to the transport box 22a through which an item is moved from the entrance. When t is an odd number, as shown in FIG. 20(b), the transport box 22a with "identification number 1" on the left transport shelf 22B corresponds to the transport box 22a through which an item is moved from the entrance.

number

[0057] Regarding horizontal movement from the entrance, equation (62) holds. Equation (62) can be interpreted as "If item i is lined up at the entrance at (t,0) and arrives at the destination floor at the next step (t+1,0), the horizontal movement cost is 3." A concrete example of equation (62) is shown in Figure 23(b).

number

[0058] Regarding horizontal movement from the entrance, formula (63) holds. Formula (63) is interpreted as "if item i is on the right transport shelf at (t, 0) and on the left transport shelf at the next step (t+1, 0), the horizontal movement cost is 1." A specific example of formula (63) is shown in FIG. 24(a). When t is an even number, as shown in FIG. 25(a), the transport box 22a with "identification numbers 1, 2, 3" on the right transport shelf 22A is the source transport box 22a, and the transport box 22a with "identification numbers 0, 1, 2" on the left transport shelf 22B is the destination transport box 22a. When t is an odd number, as shown in FIG. 25(b), the transport box 22a with "identification numbers 0, 1, 2" on the right transport shelf 22A is the source transport box 22a, and the transport box 22a with "identification numbers 1, 2, 3" on the left transport shelf 22B is the destination transport box 22a.

number

[0059] Regarding horizontal movement from the entrance, formula (64) holds. Formula (64) is interpreted as "if item i is on the right-hand transport shelf at (t, 0) and arrives at the destination floor in the next step (t+1, 0), the horizontal movement cost is 2." A specific example of formula (64) is shown in FIG. 24(b). When t is an even number, as shown in FIG. 26(a), the transport boxes 22a with "identification numbers 1, 2, 3" on the right-hand transport shelf 22A are the source transport boxes 22a. When t is an odd number, as shown in FIG. 26(b), the transport boxes 22a with "identification numbers 0, 1, 2" on the right-hand transport shelf 22A are the source transport boxes 22a.

number

[0060] Regarding horizontal movement from the entrance, formula (65) holds. Formula (65) is interpreted as "if item i is on the left transport shelf at (t, 0) and on the right transport shelf in the next step (t+1, 0), the horizontal movement cost is 1." A specific example of formula (65) is shown in FIG. 27(a). When t is an even number, as shown in FIG. 28(a), the transport box 22a with "identification numbers 0, 1, 2" on the left transport shelf 22B is the source transport box 22a. When t is an odd number, as shown in FIG. 28(b), the transport box 22a with "identification numbers 1, 2, 3" on the left transport shelf 22A is the source transport box 22a.

number

[0061] Regarding horizontal movement from the entrance, formula (66) holds. Formula (66) is interpreted as "if item i is on the left transport shelf at (t, 0) and arrives at the destination floor in the next step (t+1, 0), the horizontal movement cost is 1." A specific example of formula (66) is shown in FIG. 29. When t is an even number, as shown in FIG. 28(a), the transport box 22a with "identification numbers 0, 1, 2" on the left transport shelf 22B is the source transport box 22a. When t is an odd number, as shown in FIG. 28(b), the transport box 22a with "identification numbers 1, 2, 3" on the left transport shelf 22A is the source transport box 22a.

number

[0062] Regarding horizontal movement when multiple consecutive items go from the entrance to the destination floor on the second floor (the situation shown in FIG. 21 above), a variable (67) is prepared. This variable is set to "weight: s-1", where s is the number of consecutive items. Furthermore, equations (68) and (60) hold. "Item i" is a bundled item that bundles multiple consecutive items. Equations (68) and (69) are interpreted as "the horizontal movement cost of s consecutive items going to the second floor is S+2". Equation (68) is set to "weight: s-1", and equation (69) is set to "weight: 3".

number

[0063] Next, an example of processing contents showing a control method by the control device 10 will be described with reference to Fig. 30. As shown in Fig. 30, the item information acquisition unit 12 acquires item information showing an initial movement state and a movement completion state of the item 150 when the item 150 moves in the order of the storage lane 21, the conveyor 22, and the automated warehouse 100, or when the item moves in the order of the automated warehouse 100, the conveyor 22, and the outgoing lane 121 (step S10). Next, the route calculation unit 13 calculates transport route information from the item information acquired in step S10 so as to satisfy a reference logical formula based on a constraint condition (step S20).

[0064] At this time, the route calculation unit 13 calculates whether the scheduling can be performed with the up-down movement of the transport shelves 22A and 22B M times or less as a SAT problem. The route calculation unit 13 calculates the reference logical formula to include a movement constraint regarding the movement of the item 150, an initial constraint regarding the initial state of the item 150, and an arrival constraint regarding the arrival of the item 150 at the destination. That is, the route calculation unit 13 calculates the transport route information to satisfy the reference logical formula based on the basic constraints (entrance, destination floor, lift box, existence of item) and the movement constraint (movement from entrance to transport shelf to destination floor). Furthermore, the route calculation unit 13 calculates the acquired multiple transport route information as a MaxSAT problem. The route calculation unit 13 calculates at least one of a solution that satisfies all hard clauses and maximizes the sum of weights of the satisfied soft clauses, and a solution that satisfies all hard clauses and minimizes the sum of weights of the unsatisfied soft clauses. The path calculation unit 13 calculates soft nodes (costs of vertical movement of the transport shelves 22A and 22B and horizontal movement of the article 150) in addition to the constraint conditions calculated as the above-mentioned SAT problem.

[0065] The operation control unit 11 controls the transport operation of the article 150 based on the transport route information calculated in step S20 (step S30). With the above, the control process shown in FIG. 30 ends.

[0066] Next, the operation and effects of the control device 10 and the control method of the logistics warehouse 1 according to this embodiment will be described.

[0067] In the control device 10 of the logistics warehouse 1, the item information acquisition unit 12 acquires item information indicating the initial movement state and the completed movement state of the item 150 when the item 150 moves in the order of the storage lane 21, the conveyor 22, and the automated warehouse 100, or when the item moves in the order of the automated warehouse 100, the conveyor 22, and the outgoing lane 121. In addition, the route calculation unit 13 calculates the transport route information from the item information so as to satisfy a reference logical formula based on the constraint condition. In this case, the route calculation unit 13 can calculate what transport route the item 150 should take between the initial movement state and the item completed state. At this time, the route calculation unit 13 can easily eliminate the operation that is constrained in the transport route by calculating the reference logical formula by calculating so as to satisfy the reference logical formula based on the constraint condition. As a result, the route calculation unit 13 can calculate an appropriate transport route with a small computation load. As a result, the computation load when calculating the transport route for transporting the item 150 can be reduced.

[0068] The path calculation unit 13 defines the constraint conditions as a satisfiability determination problem, and the criteria formula may include a movement constraint regarding the movement of the item 150, an initial constraint regarding the initial state of the item 150, and an arrival constraint regarding the arrival of the item 150 at the destination.

[0069] The conveyor 22 is a vertical conveyor that performs vertical conveyance by moving the article 150 in the horizontal direction while alternately raising and lowering the conveyor boxes 22a on the adjacent conveyor shelves 22A and 22B, and the path calculation unit 13 may perform calculations by considering three phases of operation that enable the article 150 to move in the horizontal direction and one lifting and lowering operation of the conveyor 22 as one step. In this way, due to the structure of the vertical conveyor, there are cases where efficient movement is possible by performing horizontal movements three times in succession, but the article does not move even if the lifting and lowering operations are performed successively. Therefore, the path calculation unit 13 makes it easier to calculate an efficient conveyance path by setting the horizontal movement to an appropriate number of phases, namely three phases, while treating the lifting and lowering operation as one step.

[0070] The route calculation unit 13 may define the acquired multiple transport route information as a satisfiability maximization problem and calculate at least one of a solution that satisfies all hard clauses and maximizes the sum of weights of the satisfied soft clauses, and a solution that satisfies all hard clauses and minimizes the sum of weights of the unsatisfied soft clauses. In this case, the route calculation unit 13 can adopt a transport route that can move items most efficiently based on the weights of the soft clauses among the transport routes that can clear the necessary constraint conditions by satisfying the hard clauses.

[0071] When items whose numbers of floors of the incoming lane 21 and outgoing lane 121 are the same as the number of floors of the target position in the automated warehouse 100 pass through the conveyor 22 in succession, the path calculation unit 13 may regard the consecutive multiple items 150 as one item (see FIG. 21). For example, if there is a restriction on the number of times the items 150 can continuously move horizontally, there is a possibility that the rear item 150 of the consecutive multiple items 150 may not be able to reach the target position as it is. In response to this, the path calculation unit 13 may regard the consecutive multiple items 150 as one item, thereby allowing the rear item 150 to reach the target position as it is.

[0072] The control method of the logistics warehouse 1 includes an item information acquisition step S10 for acquiring item information indicating an initial movement state and a completion state of the item 150 when the item 150 moves in the order of the input lane 21, the conveyor 22, and the automated warehouse 100, or when the item 150 moves in the order of the automated warehouse 100, the conveyor 22, and the outgoing lane 121, a route calculation step S20 for calculating transport route information from the item information so as to satisfy a reference logical formula based on constraint conditions, and a transport control step S30 for controlling the transport operation of the item 150 based on the transport route information.

[0073] According to this control method for the logistics warehouse 1, it is possible to obtain the same functions and effects as those of the control device 10 described above.

[0074] Next, the process contents that can further improve the transport efficiency while reducing the computation load by computing transport path information so as to satisfy a reference logical formula based on constraint conditions as described above will be described with reference to FIGS.

[0075] As described above, the control device 10 starts from the position of the storage lane 21 immediately before the item 150 is transferred to the conveyor 22, and sets the destination floor of the automated warehouse 100 as the goal. At the stage of formulating the problem as a sufficiency maximization problem, the movement operation of the conveyor 22 is defined as shown in FIG. 31. The item 150 is transported by repeating horizontal and vertical movements at the timing of the operation defined as in FIG. 31. Here, consider the case where two items 150 are transported consecutively from the storage lane 21 to the second floor of the automated warehouse 100. In this case, the items 150 can be transported to the automated warehouse by repeating horizontal movements four times. However, in the movement operation of FIG. 31, a vertical movement occurs after three horizontal movements, so four consecutive horizontal movements are not possible. Therefore, when the items 150 are transported consecutively to the second floor of the automated warehouse 100, the consecutive items are grouped together (see FIG. 21 described above) and a transport route for only horizontal movements is calculated to prevent vertical movements from occurring. Finally, the final transport route is obtained by adding horizontal movements equal to the number of consecutive items 150.

[0076] In the control device according to the embodiment described above, when two or more articles are transported continuously to a floor of the automated warehouse 100 to which the storage lane 21 is connected, the continuously transported articles 150 are grouped together and then a route is calculated. Therefore, a route that allows the vertical movement of the vertical conveyor while the articles 150 are being transported continuously cannot be calculated. However, in practice, it has been found that there are cases where the transport efficiency is improved (the number of horizontal and vertical movements is reduced) by allowing the vertical movement of the vertical conveyor while the articles 150 are being transported continuously. As an example, a transport route in which the vertical movement of the article 150 transported to the second floor is permitted for a combination of three articles 150 transported to the second floor and one article 150 transported to the fourth floor as shown in FIG. 32 will be described. The transport route searched by the control device according to the embodiment is as shown in FIG. 33. Here, the three articles 150 are regarded as one integrated article 150UNA. As shown in FIG. 33, after the transport of the two articles 150 transported to the second floor is completed, all the articles are transported to the automated warehouse 100 in five operations. When an article 150 to be transported to the second floor is on the transport machine 22, no vertical movement occurs.

[0077] Here, the conveying route shown in FIG. 33 is not the shortest conveying route. For example, the conveying route when vertical movement of the item 150 to be conveyed to the second floor is permitted is as shown in FIG. 34. As shown in FIG. 34, after the two items 150 to be conveyed to the second floor have been conveyed, all the items are conveyed to the automated warehouse 100 in four operations. When vertical movement of the item 150 to be conveyed to the second floor in FIG. 34 is permitted, one operation is less. Thus, the control device according to the embodiment cannot determine the conveying route as shown in FIG. 34.

[0078] In order to solve the problems of the above-mentioned embodiment, the following embodiment is considered, which improves the method of grouping consecutive articles 150. For example, when the number of consecutive articles is three or more, four patterns are set as shown in Fig. 35(a) to (d). In the pattern of Fig. 35(a), consecutive articles 150 are grouped together, and in the pattern of Fig. 35(b), the first and last articles 150 are separated and the rest are grouped together. In the pattern of Fig. 35(c), the first article 150 is separated and the rest are grouped together. In the pattern of Fig. 35(d), the last article 150 is separated and the rest are grouped together. In the embodiment, the control device finds a transport route as a MaxSAT problem using the four problem settings, and extracts a route with the fewest number of horizontal and vertical movements.

[0079] However, when there are four consecutive articles 150 as shown in Fig. 36, it may be possible to complete the transportation with fewer operations by grouping two of them together and allowing the remaining two to move vertically, rather than adopting the pattern in Fig. 35. The method of the embodiment has a problem in that it is not possible to search for the shortest transportation route when there are four consecutive articles 150.

[0080] In the following, a control device 10 capable of solving the problems of the above-mentioned embodiment will be described.

[0081] As shown in Fig. 31 above, in the comparative example, the article 150 was moved in the following order, with the maximum number of horizontal movements being three: "horizontal movement → horizontal movement → horizontal movement → vertical movement → ...". In this embodiment, the article is moved in the order of "... → vertical movement → ... → vertical movement → ..." as shown in Fig. 37, and a formulation is made that allows for unlimited horizontal movement between vertical movements. Since a formulation that focuses on the movement between vertical movements is particularly effective, it will be described below.

[0082] Movement Constraint (Entrance) The above-mentioned movement constraint, equation (24), is applied to the movement constraint of the leading article in the series of consecutive articles 150. That is, the path calculation unit 13 applies equation (24), which indicates the movement constraint of the article 150 on the entrance side, to the leading article in the series of consecutive articles 150.

number

[0083] The movement constraints applied to the second and subsequent items 150 are changed to equations (70), (71), (72), and (73). Equation (70) is interpreted as "if item i is lined up at the entrance at (t, 0), item i-1 is lined up at the entrance at (t, 0), and item i-1 arrives at the destination floor at (t+1, 0), then item i arrives at the destination floor at (t+1, 0) or remains lined up at the entrance at (t, 1)." Equation (71) is interpreted as "if item i is lined up at the entrance at (t, 0), item i-1 is lined up at the entrance at (t, 0), and item i-1 has not arrived at the destination floor at (t+1, 0), then item i remains lined up at the entrance at (t, 1)." Equation (72) is interpreted as "if item i is lined up at the entrance at (t, 0) and item i-1 is not lined up at the entrance at (t, 0), then item i is on the right-hand transport shelf at (t, 1) or remains lined up at the entrance." Equation (73) is interpreted as "in phases 1 and 2, the same constraints apply as before." By adopting such movement constraints, a formulation is obtained that allows the lateral movement of item 150 in the sequence "...→vertical movement →...→vertical movement →...".

number

[0084] As described above, the path calculation unit 13 takes into consideration the lateral movement of the article 150 and the vertical movement of the article 150. Specifically, the path calculation unit 13 performs calculations using the "3 phases 1 step" operation shown in FIG. 31 as the basic operation. Then, when the specific conditions (the conditions of equations (70) to (73)) are satisfied, the path calculation unit 13 performs calculations to perform control to restrict the vertical movement of the article 150. Furthermore, when the specific conditions are no longer satisfied, the path calculation unit 13 performs calculations to perform control to allow the vertical movement of the article 150.

[0085] [Soft clauses and related hard clauses] Regarding horizontal movement from the entrance when the item 150 bound for the second floor is consecutive, prepare the variable of formula (74). Formula (74) is a variable indicating that "during the transition from (t,0) to (t,1) to (t,2) to (t+1,0), the item made horizontal movement (m-k+2)+1 times." This variable has a "weight: 1." Here, m is the number of consecutive items. k represents the kth item from the top of the consecutive items moving to the destination floor in the same step. In addition, for horizontal movement, formulas (75) and (76) are set. Formula (75) is interpreted as "If item i is lined up at the entrance at (t,0), and item i+mk arrives at the destination floor in the next step (t+1,0), the horizontal movement cost is (m-k+3)." Equation (76) is interpreted as "If horizontal movement is performed (m-k+2)+1 times, horizontal movement is performed (m-k+1)+1 times. If horizontal movement is performed (m-k+1)+1 times, horizontal movement is performed (mk)+1 times. Similarly, if horizontal movement is performed (2)+1 times, horizontal movement is performed (1)+1 times. If horizontal movement is performed (1)+1 times, horizontal movement is performed (0)+1 times." Equation (75) can also calculate the horizontal movement cost when continuously transporting items bound for the second floor. When there are three consecutive items bound for the second floor, the constraints obtained from equation (75) are equations (77), (78), and (79). Equation (77) is interpreted as "If item i is lined up at the entrance at (t,0) and item i arrives at the destination floor in the next step (t+1,0), the horizontal movement cost is 3." Equation (78) is interpreted as "If item i is lined up at the entrance at (t,0) and item i+1 arrives at the destination floor at the next step (t+1,0), the horizontal movement cost is 4." Equation (79) is interpreted as "If item i is lined up at the entrance at (t,0) and item i+2 arrives at the destination floor at the next step (t+1,0), the horizontal movement cost is 5."

number

[0086] Equation (77) is a constraint when all three items 150 do not move to the destination floor in the same step. Here, as an example in which the operation can be shown with a reduced number of steps for ease of understanding, consider the case of "m=2". As shown in Figures 38 to 40, the route calculation unit 13 determines the transport route for a situation (see Figure 38(a)) in which one item 150 is transported to the fourth floor, one item 150 is transported to the third floor, two items are transported to the second floor, and one item 150 is transported to the third floor. In this case, the items 150 transported to the second floor are moved in separate steps, as shown in Figures 40(c) and 40(d). The route calculation unit 13 uses equation (77) to evaluate the number of horizontal movements when the items 150 transported to the second floor are transported in separate steps.

[0087] Equation (78) is a constraint when the first and second items 150 or the second and third items 150 move to the destination floor in the same step. Consider the case of "m=3" as an example. As shown in FIG. 34, when a transport route is calculated for one situation of three items to be transported to the second floor and an item 150 to be transported to the fourth floor, the first two items 150 to be transported to the second floor are moved continuously in the same step, and only the last one is moved in a different step. The route calculation unit 13 uses equation (78) to evaluate the number of horizontal moves for the first two items that are moved continuously.

[0088] Equation (79) is a constraint when all three items 150 move to the destination floor in the same step. As an example, consider the case of "m=3". As shown in Figures 41 and 42, when a transport route is determined for a situation in which there are three items to be transported to the second floor, all the items are transported by continuous horizontal movements. The route calculation unit 13 uses equation (79) to evaluate the number of horizontal movements when all the items 150 to be transported to the second floor are transported in the same step.

[0089] With the above constraints, the route calculation unit 13 can calculate a transport route with the fewest number of operations while allowing the vertical movement of the transport machine 22 for all consecutive articles 150. The route calculation unit 13 defines the acquired multiple transport route information as a sufficiency maximization problem. Then, the route calculation unit 13 searches for transport route information that minimizes the horizontal (lateral) cost of the articles 150.

[0090] As described above, the path calculation unit 13 performs control that takes into account the horizontal movement of the article 150 and the vertical movement of the article 150. As a result, the path calculation unit 13 can calculate an efficient transport path by considering the balance between the number of horizontal movements and the number of vertical movements. Furthermore, the path calculation unit 13 performs calculations to perform control to restrict the vertical movement of the article 150 when a specific condition is satisfied. As a result, the path calculation unit 13 can continuously perform horizontal movements without restrictions depending on the situation. Therefore, the path calculation unit 13 can search for an efficient transport path depending on the situation. As described above, the calculation load when calculating a transport path for transporting the article 150 can be reduced.

[0091] The path calculation unit 13 may apply, to the leading one of the consecutive items 150, an equation indicating that the item 150 on the entrance side is on the entrance side transport shelf in the next phase or remains lined up at the entrance side as it is, as a reference theoretical equation indicating the movement constraint of the item 150 on the entrance side. In this case, it becomes possible to use the conventional constraint "equation (24)" as it is.

[0092] The route calculation unit 13 may define the acquired multiple pieces of transport route information as a sufficiency maximization problem, and search for transport route information that minimizes the lateral cost of the item 150. In this case, the route calculation unit 13 can adopt a transport route that can move the item most efficiently based on the cost of moving the item 150 in the lateral direction.

[0093] The present invention is not limited to the above-described embodiments.

[0094] The above-mentioned SAT problem and various constraint conditions of MaxSAT are merely examples and can be changed as appropriate. In addition, the number of floors of the automated warehouse 100, the number of floors of the conveyors 22, the storage lanes 21, and the delivery lanes 121 can also be changed as appropriate, and the constraint conditions can be changed accordingly.

[0095] For example, the logistics warehouse is not limited to the one shown in Fig. 1. For example, a plurality of automated warehouses may be provided in parallel with respect to a pair of storage lane 21 and outgoing lane 121. [Explanation of symbols]

[0096] 1... logistics warehouse, 10... control device, 12... item information acquisition unit, 13... route calculation unit, 21... storage lane (transport lane), 22... conveyor, 100... automated warehouse, 121... outgoing lane (transport lane), 150... item.

Claims

1. An automated warehouse for storing items; A conveying lane for conveying the plurality of aligned articles; A control device for a logistics warehouse comprising a conveyor provided between the conveying lane and the automated warehouse, an item information acquisition unit that acquires item information indicating an initial movement state and a movement completion state of the item when the item moves in the conveying lane, the conveyor, and the automated warehouse in this order; a route calculation unit that calculates transport route information from the item information so as to satisfy a reference logical expression based on a constraint condition; an operation control unit that controls a transport operation of the logistics warehouse based on the transport route information; The conveyor is a vertical conveyor that vertically conveys the articles by moving the articles in a lateral direction while alternately raising and lowering adjacent conveying boxes, The path calculation unit is a control that accounts for the lateral movement of the article and the longitudinal movement of the article; and a control device for restricting the vertical movement of the item when a specific condition is satisfied.

2. 2. The control device for a logistics warehouse according to claim 1, wherein the path calculation unit applies, to the leading one of the consecutive items, an equation indicating that the item on the entrance side will be on a transport shelf on the entrance side in the next phase or will remain lined up on the entrance side as it is, as a reference theoretical equation indicating a movement constraint for the item on the entrance side.

3. The path calculation unit is The plurality of pieces of transportation route information obtained are defined as a satisfiability maximization problem; The control device for a logistics warehouse according to claim 1 , further comprising: searching for the transport route information that minimizes the lateral cost of the item.

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