Control system for logistics warehouses

Abstract

To provide a distribution warehouse control device capable of reducing a calculation load when calculating a conveyance route for conveying an article.SOLUTION: An automatic warehouse 100 includes a temporary storage area 125 adjacent to a conveyor 22. A route calculation section 13 calculates conveyance information so as to satisfy first standard logical equations (for example Equations (84) to (86)) expressing constraints relevant to delivery of an article 150 into the temporary storage area 125 and second standard logical equations (for example Equations (112) to (121)) expressing constraints relevant to transfer of the article 150 into the temporary storage area. Using the first and second standard logical equations, the route calculation section 13 can easily eliminate an action prohibited on the conveyance route and thereby efficiently searching the conveyance route utilizing the temporary storage area 125.SELECTED DRAWING: Figure 32

Description

[Technical Field]

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

[0002] Conventionally, a logistics warehouse for storing goods is known, for example, the one described in Patent Document 1. This logistics warehouse receives goods from a transport lane and stores them in an automated warehouse. This logistics warehouse also transports and retrieves the goods stored in the automated warehouse at predetermined intervals. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2018-81008 [Overview of the project] [Problems that the invention aims to solve]

[0004] In an automated warehouse, a large number of items are stored. Therefore, the control system needs to calculate efficient transport routes when items are received and when items are retrieved. However, calculating such transport routes presents a problem in that it places an enormous computational load on the system.

[0005] Therefore, the present invention aims to provide a control device for a logistics warehouse that can reduce the computational load when calculating a transport route for transporting goods. [Means for solving the problem]

[0006] A control device for a logistics warehouse according to one aspect of the present invention is a control device for a logistics warehouse comprising an automated warehouse for storing goods, a transport lane for transporting a plurality of arranged goods, and a transporter provided between the transport lane and the automated warehouse, wherein when goods move in the order of transport lane, transporter, and automated warehouse, the control device comprises: an item information acquisition unit that acquires item information indicating the initial state and completed state of movement of the goods; a route calculation unit that calculates transport route information from the item information so as to satisfy a standard 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 automated warehouse is provided with a temporary storage area adjacent to the transporter, and the route calculation unit calculates transport route information so as to satisfy a first standard logical formula relating to constraint conditions regarding the entry of goods into the temporary storage area and a second standard logical formula relating to constraint conditions regarding the movement of goods into the temporary storage area.

[0007] In a control system for a logistics warehouse, the item information acquisition unit acquires item information indicating the initial and completed states of item movement when an item moves in the order of transport lane, transporter, and automated warehouse, or in the order of automated warehouse, transporter, and transport lane. The route calculation unit calculates transport route information from the item information so as to satisfy a standard logical formula based on constraints. In this case, the route calculation unit can calculate what transport route the item should take between its initial state and its completed state. At this time, by calculating to satisfy the standard logical formula based on constraints, the route calculation unit can easily eliminate constraints on the transport route, such as operations that are restricted in the transport route. As a result, the route calculation unit can calculate an appropriate transport route with a low computational load. Furthermore, the automated warehouse is provided with a temporary storage area adjacent to the transporter. The route calculation unit calculates transport route information so as to satisfy a first standard logical formula related to constraints regarding the entry of items into the temporary storage area and a second standard logical formula related to constraints regarding the movement of items into the temporary storage area. In this way, the path calculation unit can efficiently search for a transport route using a temporary placement area by easily eliminating constraints on the transport route, such as operations that are restricted along the transport route, using the first and second reference logic formulas. As a result, the computational load when calculating a transport route for transporting goods can be reduced.

[0008] The conveyor is a vertical conveyor that performs vertical conveyance by moving items laterally while alternately raising and lowering a first conveyor shelf adjacent to the temporary placement area and a second conveyor shelf adjacent to the first conveyor shelf. The path calculation unit performs calculations by considering three phases of operation that enable the lateral movement of items and one raising and lowering operation of the conveyor as one step, and the hierarchy of the temporary placement area that can be moved from the vertical conveyor may be defined. Thus, due to the structure of the vertical conveyor, there are cases in which efficient movement is possible by moving items laterally about three times in a row, but no movement of items occurs even if the raising and lowering operation is performed in a row. Therefore, by making the lateral movement into an appropriate number of phases, which is three, and the raising and lowering operation into one step, the path calculation unit can easily calculate an efficient conveyance path. In addition, since the hierarchy of the temporary placement area that can be moved from the vertical conveyor is defined, the path calculation unit can calculate the conveyance path by appropriately considering the temporary placement area at each hierarchy.

[0009] The conveyor is a vertical conveyor that performs vertical conveyance by moving items laterally while alternately raising and lowering a first conveyor shelf adjacent to the temporary placement area and a second conveyor shelf adjacent to the first conveyor shelf. The path calculation unit calculates conveyance path information by referring to auxiliary logical formulas related to constraints on the first conveyor shelf. As a result, the path calculation unit can efficiently search for a conveyance path using the temporary placement area while easily eliminating operations that are constrained by the relationship with the first conveyor shelf by using auxiliary logical formulas.

[0010] The path calculation unit may define the acquired multiple transport path information as a satisfaction maximization problem and search for transport path information that minimizes the lateral cost of the goods. In this case, the path calculation unit can adopt the transport path that moves the goods most efficiently based on the cost of moving the goods laterally. [Effects of the Invention]

[0011] According to the present invention, the computational load when calculating a transport route for transporting an article can be reduced. [Brief explanation of the drawing]

[0012] [Figure 1] It is a schematic side view showing a distribution warehouse including a control device according to an embodiment of the present invention. [Figure 2] It is a schematic configuration diagram showing the configuration of a distribution warehouse according to an embodiment of the present invention. [Figure 3] It is a diagram modeling a distribution warehouse. [Figure 4] It is a block configuration diagram of the control device according to the present embodiment. [Figure 5] It is a diagram modeling a distribution warehouse. [Figure 6] It is a diagram modeling a distribution warehouse. [Figure 7] It is a diagram illustrating specific contents of a logical formula. [Figure 8] It is a diagram illustrating specific contents of a logical formula. [Figure 9] It is a diagram illustrating specific contents of a logical formula. [Figure 10] (a) is a diagram showing the relationship between phases and movement directions, and (b) is a diagram modeling a distribution warehouse. [Figure 11] (a) is a diagram illustrating specific contents of a logical formula, and (b) and (c) are diagrams modeling a distribution warehouse. [Figure 12] (a) is a diagram illustrating specific contents of a logical formula, and (b) and (c) are diagrams modeling a distribution warehouse. [Figure 13] It is a diagram modeling a distribution warehouse. [Figure 14] (a) is a diagram illustrating specific contents of a logical formula, and (b) and (c) are diagrams modeling a distribution warehouse. [Figure 15] It is a diagram modeling a distribution warehouse. [Figure 16] (a) is a diagram illustrating specific contents of a logical formula, and (b) and (c) are diagrams modeling a distribution warehouse. [Figure 17] (a) is a diagram illustrating specific contents of a logical formula, and (b) and (c) are diagrams modeling a distribution warehouse. [Figure 18] (a) is a diagram illustrating the specific contents of a logical formula, and (b) and (c) are diagrams modeling a logistics warehouse. [Figure 19] This is a diagram modeling a logistics warehouse. [Figure 20] This is a diagram modeling a logistics warehouse. [Figure 21] This is a diagram modeling a logistics warehouse. [Figure 22] This diagram illustrates the specific content of a logical formula. [Figure 23] This diagram illustrates the specific content of a logical formula. [Figure 24] This diagram illustrates the specific content of a logical formula. [Figure 25] This is a diagram modeling a logistics warehouse. [Figure 26] This is a diagram modeling a logistics warehouse. [Figure 27] This diagram illustrates the specific content of a logical formula. [Figure 28] This is a diagram modeling a logistics warehouse. [Figure 29] This diagram illustrates the specific content of a logical formula. [Figure 30] This is a flowchart showing the processing steps of the control device. [Figure 31] This is a diagram modeling a logistics warehouse. [Figure 32] This is a diagram modeling a logistics warehouse. [Figure 33] This is a diagram modeling a logistics warehouse. [Figure 34] This is a diagram modeling a logistics warehouse. [Figure 35] This is a diagram modeling a logistics warehouse. [Figure 36] This is a diagram modeling a logistics warehouse. [Figure 37] This is a diagram modeling a logistics warehouse. [Figure 38] This is a diagram modeling a logistics warehouse. [Figure 39] This is a diagram modeling a logistics warehouse. [Figure 40]This is a diagram modeling a logistics warehouse. [Figure 41] This is a diagram modeling a logistics warehouse. [Figure 42] This is a diagram modeling a logistics warehouse. [Figure 43] This is a diagram modeling a logistics warehouse. [Modes for carrying out the invention]

[0013] Embodiments of the present invention will be described in detail below with reference to the drawings.

[0014] Figure 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 Figure 1, the logistics warehouse 1 is a system that receives and stores a plurality of articles 150, and can dispatch articles 150 that need to be dispatched from among the stored articles 150. The logistics warehouse 1 comprises an automated warehouse 100, a dispatch elevator 104 (conveyor), a receiving elevator 105 (conveyor), a dispatch lane 121 (conveyor lane), and a receiving lane 21 (conveyor lane). The automated warehouse 100 is a warehouse for storing articles 150. The automated warehouse 100 comprises a warehouse body 101, a dispatch connecting passage 102, and a receiving connecting passage 103. The warehouse body 101 has multiple shelves 110. The shelves 110 extend from one end of the warehouse body 101 to the other end. At shelf 110, the transfer device 111 performs the transfer operation of goods from the inbound route to the outbound route. The inbound passageway 103 is provided at one end of the warehouse body 101 and is a mechanism for loading goods 150 into each shelf 110. The outbound passageway 102 is provided at the other end of the warehouse body 101 and is a mechanism for retrieving goods 150 from each shelf 110. The inbound elevator 105 raises and lowers the goods 150 being loaded from the inbound lane 21 and supplies the goods 150 to the inbound passageway 103 of the desired shelf 110. The outbound elevator 104 receives the goods 150 to be retrieved from the shelf 110 and the outbound passageway 102 and raises and lowers them to an outbound opening (not shown). The goods 150 that have been retrieved from the outbound elevator 104 are transported to the outbound lane 121.

[0015] Figure 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 outbound elevator 104 may be simply referred to as "conveyor 22". Figure 2 shows the configuration of the receiving side of the logistics warehouse 1. The outbound side of the logistics warehouse 1 has the same configuration as the receiving side, except that the flow of goods 150 is through the automated warehouse 100, conveyor 22 (outbound elevator 104), and outbound lane 121, so the description will be omitted. As shown in Figure 2, the logistics warehouse 1 includes a conveying system 2 for conveying goods 150 and a control device 10 for controlling the conveying system 2. The conveying system 2 includes an receiving lane 21, a conveyor 22, and a conveyor 23 of the automated warehouse 100. Of these, the conveyor 22 is the equipment that constitutes the receiving elevator 105 mentioned above. The receiving lane 21 is a device that horizontally conveys the goods 150 and hands them over to the conveyor 22. The receiving lane 21 is provided for a predetermined level of the conveyor 22. The conveyor 23 is a device that receives goods from the conveyor 22 and transports them horizontally on each floor of the automated warehouse 100. The conveyor 23 is provided on each floor (in this case, the fourth floor) of the receiving passageway 103.

[0016] The conveyor 22 is a device that moves articles 150 in both the vertical and horizontal directions, and is equipped with a horizontal moving means (e.g., a conveyor) and a vertical moving means. Each article 150 being stored is associated with a destination floor. The conveyor 22 then moves each article 150 to its destination floor in the storage passageway 103. In the diagram, articles 150 whose destination is the "n floor" are labeled with the number "n". The same applies to subsequent diagrams. Furthermore, in the following explanation, articles 150 whose destination is the n floor may be referred to as "articles going to the n floor".

[0017] The conveyor 22 is a vertical conveyor that performs vertical conveyance by moving the goods 150 horizontally (laterally) while alternately raising and lowering a plurality of adjacent conveyor boxes 22a. The conveyor 22 is an alternating lifting device and has a conveyor shelf 22A on the receiving lane 21 side and a conveyor shelf 22B on the conveyor 23 side. Each of the conveyor shelves 22A and 22B has a storage area CE with a number of levels equal to "number of floors of the automated warehouse + one floor". It also has a continuous series of conveyor boxes 22a with a number of levels equal to "number of floors of the automated warehouse" (four levels in this case). The continuous conveyor boxes 22a move up and down simultaneously. When the continuous conveyor boxes 22a move downward, each conveyor box 22a is placed in the storage area CE from the first to the fourth level from the bottom up. When the continuous conveyor boxes 22a move upward, each conveyor box 22a is placed in the storage area CE from the second to the fifth level from the bottom up. In the following explanation, when simply referring to the number of tiers, unless otherwise specified, it will refer to the number of tiers counted from the bottom. Also, the transport boxes 22a of transport shelf 22A and the transport boxes 22a of transport shelf 22B move up and down alternately. That is, when the transport box 22a of transport shelf 22A moves upward, the transport box 22a of transport shelf 22B moves downward. This allows the items 150 in transport shelf 22A to be raised by one tier (see operation M1). Also, when the transport box 22a of transport shelf 22A moves downward, the transport box 22a of transport shelf 22B moves upward. This allows the items 150 in transport shelf 22B to be raised by one tier. Furthermore, within the same number of tiers, the items 150 can be moved horizontally between the transport boxes 22a of transport shelf 22A and the transport boxes 22a of transport shelf 22B, allowing for the transfer and receipt of items 150 between them (see operation M2). Furthermore, the goods 150 can be transferred from the transport box 22a of the transport shelf 22B to the conveyor 23 on the target floor (see operation M3).

[0018] In this embodiment, an receiving lane 21 is provided for the second-to-last storage area CE from the bottom, and four conveyors 23 are provided for the first to fourth-to-last storage areas CE from the bottom. In Figure 2, the areas indicated as "S1" and "S2" within the storage area CE 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 receiving lane 21, and the conveyors 23 is not particularly limited and may be set as appropriate according to the configuration of the logistics warehouse 1.

[0019] In the following explanation, the logistics warehouse 1 may be modeled as shown in Figure 3. The transport box 22a of the transporter 22 is shown as a single rectangle. Each item 150 can move simultaneously horizontally, provided there are no obstructions. In terms of vertical movement, while the transport shelves of the transporter 22 are moving vertically, the items 150 inside the transporter 22 cannot move. While the transporter 22 is moving vertically, the receiving lane 21 and the conveyor 23 can move horizontally. In the following explanation, 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 Figure 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 Figure 3(b), may be referred to as the "right transport shelf raised state." Furthermore, each transport box 22a in transport racks 22A and 22B is assigned an identification number, "0, 1, 2, 3," from bottom to top. In the diagram, this identification number is shown as a number enclosed in a circle inside the transport box 22a.

[0020] Next, the block configuration of the control device 10 will be described with reference to Figure 4. Figure 4 is a block diagram of the control device 10 according to this embodiment. The control device 10 is a unit that controls the transport system 2. The control device 10 is equipped with an ECU (Electronic Control Unit) that comprehensively manages the logistics warehouse 1. The ECU is an electronic control unit that has a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), and communication circuits such as CAN (Controller Area Network). In the ECU, for example, various functions are realized by loading a program stored in ROM into RAM and executing the program loaded into RAM with the CPU. The control device 10 includes an operation control unit 11, an item information acquisition unit 12, and a path calculation unit 13.

[0021] The motion 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 path calculated by the path calculation unit 13. The motion control unit 11 controls the transport operation by transmitting control signals to the transport system 2. The motion control unit 11 operates each of the drive units of the receiving lane 21, transporter 22, and conveyor 23 of the transport system 2 by transmitting control signals to each of the drive units.

[0022] The item information acquisition unit 12 acquires item information indicating the initial and completed states of movement of the item 150 when the item 150 moves in the order of receiving lane 21, conveyor 22, and automated warehouse 100, or when it moves in the order of automated warehouse 100, conveyor 22, and outbound lane 121. The initial state of movement is the state in which the item 150 to be transported is present in receiving lane 21, as shown in Figure 5(a). The completed state of movement is the state in which all of the item 150 to be transported has been transported to the automated warehouse 100, as shown in Figure 5(b). The item information includes information such as the destination floor number of the item 150 present in receiving lane 21, the number of items 150 on each floor, and the order in which the items are transported. The item information also includes information such as how many items 150 are to be dispatched from which floor of the automated warehouse 100, and the order in which they are dispatched.

[0023] The path calculation unit 13 is a unit that calculates transport path information from item state information so as to satisfy a standard logical formula based on constraint conditions. The path calculation unit 13 searches for the transport path of each item 150 in the transport system 2. Here, between the initial movement state and the completed movement state shown in Figure 5(a), the transport system 2 simultaneously performs horizontal and vertical movement of each item 150, and transports each item 150 to its destination by combining these movements. At this time, the control device 10 moves the items 150 so that they do not interfere with each other and can be sorted quickly under the operational constraints of the transport system 2. At this time, the path calculation unit 13 calculates what path each item 150 will take to reach its destination within the transport system 2. The path calculation unit 13 searches for the path of each item 150 using a shortest path search method or the like, with each part of the transport system 2 as a search node for a predetermined number of items 150.

[0024] Here, the path calculation unit 13 defines the constraints as a Satisfiability Problem (SAT problem). A SAT problem is a problem that determines whether there exists an assignment of values ​​to a propositional variable that makes a theoretical formula containing propositional variables true. Solving a SAT problem is about solving a decision problem, that is, finding out whether or not there is a solution that satisfies the constraints. For example, to the question, "Can all items 150 reach the target floor with five or fewer up-and-down movements of the transport racks 22A and 22B of the transporter 22?", the answer given is, "Yes. The specific schedule is ~." The base logical formula includes movement constraints regarding the movement of items 150, initial constraints regarding the initial state of the items, and arrival constraints regarding the arrival of items 150 at their destination.

[0025] Furthermore, the route calculation unit 13 defines the acquired transport route information as a Maximum Satisfiability Problem (MaxSAT problem). The MaxSAT problem is the problem of finding the ratio of variables that maximizes the number of satisfied nodes for a given set of nodes as input. Solving the MaxSAT problem is an optimization problem, that is, finding the optimal solution that satisfies the constraints. For example, to the problem, "What is the shortest time for all 150 items to reach the destination floor?", the answer given is "10 seconds. The specific schedule is ~." The route calculation unit 13 calculates at least one of the following: a solution that satisfies all hard nodes and maximizes the sum of the weights of the satisfied soft nodes, and a solution that satisfies all hard nodes and minimizes the sum of the weights of the unsatisfied soft nodes. Hard nodes are nodes that must be satisfied. Soft nodes are nodes that should be satisfied as much as possible, and the degree to which they are satisfied is represented by a weight (a positive integer).

[0026] [Preparing for the explanation] First, before explaining the constraints for SAT and MaxSAT problems, let's define the terminology. From here on, the terms will be explained as common to both SAT and MaxSAT problems. A "constraint" is represented by a set of clauses. A "clause" is the logical OR of literals and is shown by equation (1) below. A "literal" is a logical variable or its negation and is shown by equation (2). A "variable" takes the value of either "True" or "False," with True sometimes being considered as "1" and False as "0." In this specification, equations (3), (4), and (5) will be used as substitutes for clauses. Note that equation (3) can also be expressed as equation (6).

number

[0027] Equations (3) and (6) mean "in the current state, a1 to a m If all of the above are true, then from c1 to c n It is interpreted as "one of the following must be true." Using equations (3) and (6), for example, "if the item is on XX on the right-hand transport rack (meaning a in each case), then in the following cases it is either stopped there or on YY on the left-hand transport rack (meaning c in each case)." Equation (4) is "from l1 to l n This can be interpreted as "only one of these will be true." n If all conditions are False, the left side of equation (4) becomes "0". That is, the left side of equation (4) is either "1" or "0". Equation (4) can be used to show, for example, that "at most one item can be placed in each transport box on the transport rack (each transport box means l)". This means that the same item 150 cannot exist in the same transport box 22a at the same time. If an item 150 does not enter any of the transport boxes 22a, the left side of equation (4) becomes "0". Equation (5) is "from l1 to l nThis is interpreted as "exactly one of these will be true." Equation (5) can be used to show, for example, that "a certain item is always located in either the receiving lane, the transport shelf, or the destination floor (each location representing l)." In the following explanation, when the term "entrance" is used to describe the constraints, it refers to receiving lane 21. Also, when the term "item" is used to describe the constraints, it refers to item 150.

[0028] [Steps and Phases] In this explanation, the initial state of the logistics warehouse 1 is assumed to be as shown in Figure 3(a), with the left transport rack 22B raised and the right transport rack 22A lowered. The route calculation unit 13 performs calculations using a three-phase operation that enables the lateral movement of the goods 150, and one lifting and lowering operation of the transporter 22 as one step. The route calculation unit 13 uses the "three phases, one step" operation as its basic operation and repeats this operation. As shown in Figure 6, in each phase, the goods 150 can move horizontally to an adjacent position. The number of goods that move horizontally in one phase is not particularly limited, and it is also possible for no goods to move horizontally. The route calculation unit 13 may omit phases in which no horizontal movement occurs when calculating the transport route in later calculations without allocating time to them. When the three phases are completed, the step switches. At the timing of the step change, the transport shelves 22A and 22B are switched between the "left transport shelf raised state (see Figure 3(a))" and the "right transport shelf raised state (see Figure 3(b))". This repetitive basic operation is based on the inventors' discovery that even if the switching operation of transport shelves 22A and 22B occurs continuously, the movement of the article 150 does not progress, whereas even if the horizontal movement of the article 150 is performed continuously, the movement of the article 150 does progress. Furthermore, the inventors have found that even if horizontal movement is performed four or more times consecutively, the movement of the article 150 does not progress (with some exceptions), so they adopted 3 as the appropriate number of phases in one step. The reason for the number of phases being 3 is that, during the time when vertical movement is not performed within transport shelves 22A and 22B (during one step), horizontal movement to the right occurs a maximum of once, and left movement occurs a maximum of twice (with some exceptions), so the sum of these is 3.

[0029] The variables used to indicate steps and phases are explained below. (7) below is a variable that indicates "the i-th item is lined up at the entrance in phase p of step t". (8) is a variable that indicates "the i-th item is on the target floor in phase p of step t". (9) is a variable that indicates "the i-th item is in transport box j on the left transport shelf in phase p of step t". Note that "j" which identifies transport box 22a is the identification number shown in the circle in Figure 3. (10) is a variable that indicates "the i-th item is in transport box j on the right transport shelf in phase p of step t". In the following explanation, "phase p of step t" may be abbreviated as "(t,p)" to indicate time. Note that the subscript is "0-origin". Also, the start is "step 0, phase 0". Therefore, (t,p) transitions as follows: "(0,0)→(0,1)→(0,2)→(1,0)→(1,1)→…". At the timing of the step t change, the switching operation of the transport shelves 22A and 22B is performed. If step t is even, it indicates that the "left transport shelf is raised (see Figure 3(a))", and if step t is odd, it indicates that the "right transport shelf is raised (see Figure 3(b))". To represent the transition of (t,p), the variable shown in (11) is used. (11) is a variable that returns the next step and phase of (t,p). Specifically, the variable in (11) is shown in Figure 7(a).

number

[0030] [Entrance constraints] The constraints relating to the entrance (i.e., the receiving lane 21) are explained below. The base logic formula includes the logic formulas (12) and (13), which represent the entrance constraints, as initial constraints relating to the initial state. Formula (12) is interpreted as "if item i is lined up at the entrance at (t,p), then it was lined up before that as well." Formula (13) is interpreted as "if item i is lined up at the entrance at (t,p), then item i+1 is also lined up." The specific details of formula (12) are shown in Figure 7(b). The specific details of formula (13) are shown in Figure 7(c). Note that "M" represents the maximum vertical movement of the conveyor racks 22A and 22B. The meaning of "M" remains the same in the following explanation.

number

[0031] [Objective-level constraints] This section explains the constraints regarding the destination floor of automated warehouse 100. The standard logic formula includes the logic formula (14), which represents the destination floor constraint, as an arrival constraint regarding the arrival of goods at the destination floor. Formula (14) is interpreted as "if goods i have arrived at the destination floor at (t,p), then remain so thereafter." The specific details of formula (14) are shown in Figure 8(a).

number

[0032] [Constraints on transport boxes for transport shelves] This section describes the constraints on the transport boxes 22a of transport shelves 22A and 22B. The basic logical formula includes the transport box constraints, expressed as movement constraints on the movement of goods, in the form of formulas (15) and (16). Formula (15) is interpreted as "at (t,p), the transport box j on the left transport shelf cannot contain more than two goods." Formula (16) is interpreted as "the transport box j on the right transport shelf cannot contain more than two goods." Note that "N" represents the number of goods. The same applies to subsequent logical formulas. Formula (17) shows the range of possible values ​​for (t,p).

number

[0033] [Constraints on the existence of goods] The constraints regarding the existence of an item within transport system 2 are explained. The basic logical formula includes, as a movement constraint, the logical formula (18) which shows the existence constraint regarding the existence of an item during its movement. Formula (18) is interpreted as "At (t,p), item i is either lined up at the entrance, in a transport rack, or has reached the destination floor." Formula (19) shows the range of possible values ​​for (t,p).

number

[0034] [Auxiliary function (position of transport box)] Auxiliary functions are set to show the relationship between the transport boxes 22a of transport shelves 22A and 22B. (20) shown below is an auxiliary function that shows "a transport box on the left transport shelf that can move from transport box j on the right transport shelf". (21) shown below is an auxiliary function that shows "a transport box on the right transport shelf that can move from transport box j on the left transport shelf". (22) shown below is an auxiliary function that shows "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 shows "a transport box on the right transport shelf that is stopped at the entrance floor at step t".

number

[0035] The specific details of the auxiliary function (20) are shown in Figure 9(a). The specific details of the auxiliary function (21) are shown in Figure 9(b). The specific details of the auxiliary function (22) are shown in Figure 9(c). The specific details of the auxiliary function (23) are shown in Figure 9(d). If step t is even, the left transport shelf is in the "upward position (see Figure 3(a))" state. Therefore, the relationship between the transport box 20a of the right transport shelf 22A and the transport box 22a of the left transport shelf 22B is shown in Figure 3(a). Also, for the transport boxes 22a of transport shelves 22A and 22B that are stopped on the 2nd floor, which is the entrance floor, the right transport shelf 22A has "identification number 1" and the left transport shelf 22B has "identification number 0", as shown in Figure 3(a). If step t is odd, the right transport shelf is in the "upward position (see Figure 3(b))" state. 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 Figure 3(b). Furthermore, for the transport boxes 22a on transport shelves 22A and 22B that are stopped on the second floor, which is the entrance floor, the transport box 22a on the right transport shelf 22A is "identification number 0" and the transport box 22a on the left transport shelf 22B is "identification number 1", as shown in Figure 3(b).

[0036] [Movement Restrictions (Entrance)] This section explains the constraints on the movement of items when they are lined up at the entrance. The standard logic formula includes the logic formula (24), which shows the movement constraint of items on the entrance side, as a movement constraint. Formula (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 or still lined up at the entrance." The specific details of formula (24) are shown in Figure 8(b).

number

[0037] [Movement constraints (transport shelves)] This section describes the constraints on the movement of items when they are located on transport shelves 22A and 22B. Here, we explain the basic conditions for movement constraints on transport shelves 22A and 22B. Of the three phases, the first two phases involve movement to the left, and the last phase involves movement to the right. Figure 10(a) shows the relationship between the specific phases and the direction of movement. By setting these conditions, as shown in Figure 10(b), it becomes possible to eliminate the operation in which item A on transport shelf 22B and item B on transport shelf 22A suddenly swap places in the next phase when each item A and B are moving horizontally. The standard logical formula includes the logical formulas (25) and (26) as movement constraints, which show the movement constraints for items placed in the immovable transport box on the right-hand transport shelf 22A. Formula (25) is interpreted as, "When item i is in transport box "0" on the right-hand transport shelf at (t,p) where t is an even number, in the next phase next(t,p), it will be in the same transport box "0"." Equation (26) is interpreted as "when item i is in transport box "3" on the right-hand transport rack in (t,p) when t is odd, it will be in the same transport box "3" in the next phase next(t,p)." The specific details of equations (25) and (26) are shown in Figure 11(a). When t is even, the bottom transport box 22a of "identification number 0" on the right-hand transport rack 22A is not adjacent to any other transport boxes 22a, the automated warehouse 100, or the receiving lane 21 (see Figure 11(b)). When t is odd, the top transport box 22a of "identification number 3" on the right-hand transport rack 22A is not adjacent to any other transport boxes 22a, the automated warehouse 100, or the receiving lane 21 (see Figure 11(c)). Therefore, items placed in the transport boxes 22a of "identification numbers 1 and 3" cannot move to any location in the next phase and remain in place.

number

[0038] The standard logic formula includes the logic formulas (27) and (28) as movement constraints, which show the movement constraints for items placed in transport boxes that are allowed to move to the left on floors other than the entrance floor of the right-hand transport rack 22A. Formula (27) is interpreted as "When an item i in transport box j of the right-hand transport rack transitions from (t,0) to (t,1), it moves to the left or remains in the same transport box j." Formula (28) is interpreted as "When an item i in transport box j of the right-hand transport rack transitions from (t,1) to (t,2), or from (t,2) to (t+1,0), it remains in the same transport box j." The specific details of formulas (27) and (28) are shown in Figure 12(a). When t is an even number, as shown in Figure 12(b), the transport boxes 22a with "identification numbers 2,3" on the right-hand transport rack 22A correspond to the transport boxes 22a that are allowed to move to the left on floors other than the entrance floor, the 2nd floor. When t is an odd number, as shown in Figure 12(c), the transport boxes 22a with "identification numbers 1 and 2" on the transport rack 22A on the right side correspond to the transport boxes 22a that can move to the left, except on the 2nd floor which is the entrance floor.

number

[0039] The standard logic formula includes the logic formulas (29), (30), and (31) as movement constraints, which show the movement constraints of an item placed in a transport box stopped at the entrance floor of the right-hand transport rack 22A. Formula (29) is interpreted as "When an item i in transport box j of the right-hand transport rack transitions from (t,0) to (t,1), it moves to the left or remains in the same transport box j." Formula (30) is interpreted as "When an item i in transport box j of the right-hand transport rack transitions from (t,1) to (t,2), or from (t,2) to (t+1,0), it remains in the same transport box j if it was there immediately before." Equation (31) is interpreted as follows: "When an item i in a transport box j on the right-hand transport rack transitions from (t,1) to (t,2), or from (t,2) to (t+1,0), if it was not there immediately before, it moves to the left or remains in the same transport box j." When t is even, as shown in Figure 13(a), the transport box 22a with "identification number 1" on the right-hand transport rack 22A corresponds to the transport box 22a that is stopped on the 2nd floor, which is the entrance floor. When t is odd, as shown in Figure 12(b), the transport box 22a with "identification number 0" on the right-hand transport rack 22A corresponds to the transport box 22a that is stopped on the 2nd floor, which is the entrance floor.

number

[0040] The standard logic formula includes the logic formula (32), which shows the movement constraint for an item placed in an immovable transport box on the left transport rack 22B. Formula (32) is interpreted as "when item i is in transport box "3" on the left transport rack when t is even (t,p), in the next phase next(t,p), it will be in the same transport box "3"." The specific details of formula (32) are shown in Figure 14(a). When t is even, the top transport box 22a of "identification number 3" on the left transport rack 22B is not adjacent to any other transport boxes 22a, the automated warehouse 100, or the receiving lane 21 (see Figure 14(b)). Therefore, an item placed in transport box 22a of "identification number 3" cannot move to any location in the next phase and remains in place. When t is odd, there are no immovable transport boxes 22a on the left transport rack 22B (see Figure 14(c)).

number

[0041] The base logic formula includes the logic formulas (33), (34), and (35) as movement constraints, which show the movement constraints of items placed in the transport box on the target floor of the left transport rack 22B. Formula (33) is interpreted as "When an item i in transport box j of the left transport rack transitions from (t,0) to (t,1), it moves to the left or remains in the same transport box j." Formula (34) is interpreted as "When an item i in transport box j of the left transport rack transitions from (t,1) to (t,2), or from (t,2) to (t+1,0), it remains in the same transport box j if it was there immediately before." Equation (35) is interpreted as follows: "When an item i in a transport box j on the left transport shelf transitions from (t,1) to (t,2), or from (t,2) to (t+1,0), if it was not there immediately before, it moves to the left or remains in the same transport box j." When t is even, as shown in Figure 15(a), the transport boxes 22a with "identification numbers 0,1,2" on the left transport shelf 22B correspond to the transport boxes 22a that are stopped at the target floor. When t is odd, as shown in Figure 15(b), the transport boxes 22a with "identification numbers 0,1,2,3" on the left transport shelf 22B correspond to the transport boxes 22a that are stopped at the target floor.

number

[0042] The standard logic formula includes, as a movement constraint, the logic formula (36) which shows the movement constraint of an item placed in a transport box that is stopped on a floor other than the destination floor of the left transport rack 22B. Formula (36) is interpreted as "an item i in transport box j of the left transport rack remains in the same transport box j when transitioning from (t,0) to (t,1) or from (t,1) to (t,2)". The specific content of formula (36) is shown in Figure 16(a). When t is even, as shown in Figure 16(b), the transport boxes 22a with "identification numbers 0,1,2" on the left transport rack 22B correspond to transport boxes 22a that are stopped on a floor other than the destination floor. When t is odd, as shown in Figure 16(c), the transport boxes 22a with "identification numbers 0,1,2,3" on the left transport rack 22B correspond to transport boxes 22a that are stopped on a floor other than the destination floor.

number

[0043] The standard logical formula includes, as a movement constraint, the logical formula (37) which shows the movement constraint for an item placed in a transport box that is not on the destination floor of the left transport rack 22B and is on a floor from which movement to the right is impossible. Formula (37) is interpreted as "When item i in transport box j of the left transport rack transitions from (t,2) to (t+1,0), it remains in the same transport box j." The specific content of formula (37) is shown in Figure 17(a). When t is even, as shown in Figure 17(b), there are no floors on the left transport rack 22B that are not the destination floor and from which movement to the right is impossible. When t is odd, as shown in Figure 17(c), transport box 22a with "identification number 0" on the left transport rack 22B corresponds to transport box 22a that is not on the destination floor and from which movement to the right is impossible.

number

[0044] The standard logic formula includes the logic formulas (38) and (39) as movement constraints for items placed in a transport box that is not the destination floor of the left transport rack 22B, is able to move to the right, and is not the entrance floor. Formula (38) is interpreted as "When item i in transport box j of the left transport rack transitions from (t,2) to (t+1,0), if it is not there in phase 0, it remains in the same transport box j." Formula (39) is interpreted as "When item i in transport box j of the left transport rack transitions from (t,2) to (t+1,0), if it is there in phase 0, it either moves to the right or remains in the same transport box j." The specific details of formulas (38) and (39) are shown in Figure 18(a). When t is an even number, as shown in Figure 18(b), the transport boxes 22a with "identification numbers 1 and 2" on the left transport rack 22B correspond to transport boxes 22a that can be moved to the right, not to the destination floor, and are not on the entrance floor. When t is an odd number, as shown in Figure 18(c), the transport boxes 22a with "identification numbers 2 and 3" on the left transport rack 22B correspond to transport boxes 22a that can be moved to the right, not to the destination floor, and are not on the entrance floor.

number

[0045] Here, (40) shown below is an auxiliary variable indicating that "the item is in the transport box j on the entrance floor of the right-hand transport rack (p=2)". Using this auxiliary variable, equations (41) and (42) show that the item is in the transport box 22a, which is on the second floor of the entrance floor of the right-hand transport rack 22A, based on De Morgan's laws. When t is even, as shown in Figure 19(a), the transport box 22a with "identification number 1" on the right-hand transport rack 22A corresponds to the transport box 22a on the entrance floor. When t is odd, as shown in Figure 19(b), the transport box 22a with "identification number 0" on the right-hand transport rack 22A corresponds to the transport box 22a on the entrance floor.

number

[0046] The standard logic formula includes the logic formulas (43), (44), and (45) which, as movement constraints, indicate the movement constraints of an item placed in a transport box that is not the destination floor of the left transport rack 22B, is able to move to the right, and is stopped at the entrance floor. Formula (43) is interpreted as "When an item i in transport box j of the left transport rack transitions from (t,2) to (t+1,0), if it is not there in phase 0, it remains in the same transport box j." Formula (44) is interpreted as "When an item i in transport box j of the left transport rack transitions from (t,2) to (t+1,0), if it is there in phase 0, and the transport box to its right is empty, it either moves to the right or remains in the same transport box j." Equation (45) is interpreted as follows: "When item i in transport box j on the left transport shelf transitions from (t,2) to (t+1,0), if it is there in phase 0, and there is something in the transport box to its right, it will remain in the same transport box j." When t is even, as shown in Figure 20(a), transport box 22a with "identification number 0" on the left transport shelf 22B corresponds to transport box 22a that can move to the right, not the destination floor, and is stopped at the entrance floor. When t is odd, as shown in Figure 20(b), transport box 22a with "identification number 1" on the left transport shelf 22B corresponds to transport box 22a that can move to the right, not the destination floor, and is stopped at the entrance floor.

number

[0047] [Initial constraints and arrival constraints] Let's explain the initial constraints. Condition (46) below is True because it indicates that "all items are initially lined up at the entrance." Let's explain the arrival constraints. Condition (47) below is True because it indicates that "after M vertical movements of the transport rack, all items must have arrived at the destination floor."

number

[0048] [When there are consecutive items going to the second floor] When items with the same entry and destination floors pass through the conveyor 22 consecutively, four phases are required (for example, if there are two items) to pass through the conveyor 22 without stopping. For example, as shown in Figure 21(a), the item in the foreground can reach the destination floor (2nd floor) in three phases of horizontal movement, but the item in the background cannot reach the destination floor without four phases of horizontal movement. Thus, such bypasses are not scheduled in a 3-phase 1-step system. Therefore, the path calculation unit 13 treats multiple consecutive items as a single item. As shown in Figure 21(b), the path calculation unit 13 treats two items as a single item, such as "150B". In this case, "150B" can reach the destination floor in three phases of horizontal movement. Note that there is no particular limit to the number of items that can be grouped together; three or more items may be grouped together.

[0049] [Movement Restrictions (Entrance)] The base logic formula includes the logic formulas (48), (49), and (50) as movement constraints, which indicate movement constraints at the entrance. Formula (48) is interpreted as "item i at the entrance can move to the right-hand transport rack only during phase 0." Formula (49) is interpreted as "item i at the entrance remains at the entrance during phase 1." Formula (50) is interpreted as "item i at the entrance remains at the entrance during phase 2."

number

[0050] [Movement constraints (transport rack on the right)] The standard logic formula includes the logic formulas (51) and (52) as movement constraints, which show the movement constraints for the transport box on the entrance floor of the right-hand transport rack. Formula (51) is interpreted as "When t is even and transitioning from (t,1) to (t,2), item i in the transport box on the entrance floor of the right-hand transport rack will always move to the left-hand transport rack." Formula (51) is interpreted as "When t is odd and transitioning from (t,1) to (t,2), item i in the transport box on the entrance floor of the right-hand transport rack will always move to the left-hand transport rack." Note that there are "no constraints" when transitioning from (t,0) to (t,1) or from (t,2) to (t+1,0). When t is even, as shown in Figure 19(a), the transport box 22a with "identification number 1" on the right-hand transport rack 22A corresponds to the transport box 22a on the entrance floor. When t is an odd number, as shown in Figure 19(b), the transport box 22a with "identification number 0" on the transport rack 22A on the right corresponds to the transport box 22a on the entrance floor.

number

[0051] [Movement constraints (left-hand transport rack)] The standard logic formula includes the logic formulas (53) and (54) as movement constraints, which show the movement constraints for the transport boxes on the destination floor and entrance floor of the left transport rack. Formula (53) is interpreted as "When t is even and transitioning from (t,2) to (t+1,0), item i in the transport box on the destination floor and entrance floor of the left transport rack must move to the left." Formula (54) is interpreted as "When t is odd and transitioning from (t,2) to (t+1,0), item i in the transport box on the destination floor and entrance floor of the left transport rack must move to the left." Note that there are "no constraints" when transitioning from (t,0) to (t,1) or from (t,1) to (t,2). As shown in Figure 20(a), the transport box 22a with "identification number 0" on the left transport rack 22B corresponds to the transport box 22a that is stopped on the destination floor and entrance floor. If t is an odd number, as shown in Figure 20(b), the transport box 22a with "identification number 1" on the transport rack 22B on the left corresponds to the transport box 22a that is stopped on the destination floor and the entrance floor.

number

[0052] [Optimal Solution Search Using SAT] Next, the optimal solution search unique to SAT will be described. "S M " is defined as "the set of constraints (clauses) obtained when M is given". If S M has a solution, this can be interpreted as "all articles can reach the destination floor within M vertical movements of the conveyor shelf". If S M has no solution, this can be interpreted as "all articles cannot reach the destination floor within M vertical movements of the conveyor shelf". For example, if "S0, S1, … S m-1 " has no solution, and "S m , …" has a solution, then "m" is the optimal value.

[0053] [MaxSAT] Next, the content unique to MaxSAT will be described. For the purpose of describing MaxSAT, variables in (55) and (56) are prepared. (55) shown below is a variable indicating that "all articles 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)→(t,1)→(t,2)→(t+1,0), the article has performed k+1 horizontal movements". It should be noted that when the path calculation unit 13 calculates the MaxSAT problem, the above constraint conditions calculated as the SAT problem shall also be calculated in the same manner. [Formula]

[0054] [Hard Clauses Related to Soft Clauses] We will now explain the hard section, which is related to the soft section. First, we will explain the variable in (55) above. (55) represents the cost of moving the transport racks 22A and 22B up and down, and a "weight: 1" can be set. The logical formula shown in equation (57) holds true for this variable. "N" means the number of items. The meaning of "N" will remain the same in the following explanation. Equation (57) is interpreted as "all items have arrived at the target floor in phase 0 of step t". The specific details of equation (57) are shown in Figure 22(a).

number

[0055] Let's explain the variable in (56) above. This variable is used in a negative form, as shown in (58). (58) shows the cost of horizontal movement of an item, and a "weight: 1" can be set. Equation (59) is interpreted as "no horizontal movement of the item occurred during the transition from (t,0)→(t,1)→(t,2)→(t+1,0)".

number

[0056] Regarding horizontal movement from the entrance, equation (60) holds true. Equation (60) is interpreted as "if item i is lined up at the entrance at (t,0) and is on the right-hand transport shelf in the next step (t+1,0), the horizontal movement cost is 1." A specific example of equation (60) is shown in Figure 22(b). When t is even, as shown in Figure 19(a), the transport box 22a with "identification number 1" on the right-hand transport shelf 22A corresponds to the transport box 22a from which the item moves from the entrance. When t is odd, as shown in Figure 19(b), the transport box 22a with "identification number 0" on the right-hand transport shelf 22A corresponds to the transport box 22a from which the item moves from the entrance.

number

[0057] Regarding horizontal movement from the entrance, equation (61) holds true. Equation (61) is interpreted as "if item i is lined up at the entrance at (t,0) and is on the left-hand transport shelf in the next step (t+1,0), the horizontal movement cost is 2." A specific example of equation (61) is shown in Figure 23(a). When t is even, as shown in Figure 20(a), the transport box 22a with "identification number 0" on the left-hand transport shelf 22B corresponds to the transport box 22a from which the item moves from the entrance. When t is odd, as shown in Figure 20(b), the transport box 22a with "identification number 1" on the left-hand transport shelf 22B corresponds to the transport box 22a from which the item moves from the entrance.

number

[0058] Regarding horizontal movement from the entrance, equation (62) holds true. Equation (62) is interpreted as, "If item i is lined up at the entrance at (t,0) and arrives at the destination floor in the next step (t+1,0), then the horizontal movement cost is 3." A specific example of equation (62) is shown in Figure 23(b).

number

[0059] Regarding horizontal movement from the entrance, equation (63) holds true. Equation (63) is interpreted as "if item i is on the right-hand transport shelf at (t,0) and on the left-hand transport shelf in the next step (t+1,0), the horizontal movement cost is 1." A specific example of equation (63) is shown in Figure 24(a). When t is even, as shown in Figure 25(a), the transport boxes 22a with "identification numbers 1, 2, 3" on the right-hand transport shelf 22A are the source transport boxes 22a, and the transport boxes 22a with "identification numbers 0, 1, 2" on the left-hand transport shelf 22B are the destination transport boxes 22a. When t is odd, as shown in Figure 25(b), the transport boxes 22a with "identification numbers 0, 1, 2" on the right-hand transport shelf 22A are the source transport boxes 22a, and the transport boxes 22a with "identification numbers 1, 2, 3" on the left-hand transport shelf 22B are the destination transport boxes 22a.

number

[0060] Regarding horizontal movement from the entrance, equation (64) holds true. Equation (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 equation (64) is shown in Figure 24(b). When t is even, as shown in Figure 26(a), the transport boxes 22a with "identification numbers 1, 2, 3" on the right-hand transport shelf 22A are the transport boxes 22a from which the movement began. When t is odd, as shown in Figure 26(b), the transport boxes 22a with "identification numbers 0, 1, 2" on the right-hand transport shelf 22A are the transport boxes 22a from which the movement began.

number

[0061] Regarding horizontal movement from the entrance, equation (65) holds true. Equation (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 equation (65) is shown in Figure 27(a). When t is even, as shown in Figure 28(a), the transport boxes 22a with "identification numbers 0,1,2" on the left transport shelf 22B are the transport boxes 22a from which the movement began. When t is odd, as shown in Figure 28(b), the transport boxes 22a with "identification numbers 1,2,3" on the left transport shelf 22A are the transport boxes 22a from which the movement began.

number

[0062] Regarding horizontal movement from the entrance, equation (66) holds true. Equation (66) is interpreted as "if item i is on the left-hand 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 equation (66) is shown in Figure 29. When t is even, as shown in Figure 28(a), the transport boxes 22a with "identification numbers 0,1,2" on the left-hand transport shelf 22B are the transport boxes 22a from which the movement began. When t is odd, as shown in Figure 28(b), the transport boxes 22a with "identification numbers 1,2,3" on the left-hand transport shelf 22A are the transport boxes 22a from which the movement began.

number

[0063] Regarding the horizontal movement of multiple items in succession from the entrance to the target floor on the second floor (as shown in Figure 21 above), we prepare the variable (67). This variable is set to have a weight of "s-1", where s is the number of consecutive items. Also, equations (68) and (60) hold true. "Item i" is a bundled item formed by combining 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 a weight of "s-1", and equation (69) is set to a weight of "3".

number

[0064] Next, with reference to Figure 30, an example of the processing content showing the control method by the control device 10 will be described. As shown in Figure 30, when the item 150 moves in the order of receiving lane 21, conveyor 22, and automated warehouse 100, or when it moves in the order of automated warehouse 100, conveyor 22, and outbound lane 121, the item information acquisition unit 12 acquires item information indicating the initial state and completed state of movement of the item 150 (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 standard logical expression based on constraint conditions (step S20).

[0065] At this time, the route calculation unit 13 calculates whether scheduling is possible with M or fewer vertical movements of the transport shelves 22A and 22B as a SAT problem. The route calculation unit 13 calculates such that the base logic formula includes movement constraints regarding the movement of the item 150, initial constraints regarding the initial state of the item 150, and arrival constraints regarding the item 150 reaching its destination. That is, the route calculation unit 13 calculates the transport route information so that it satisfies the base logic formula based on the basic constraints (entrance, destination floor, lift box, presence of item) and movement constraints (movement from entrance → transport shelf → 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 the following: 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. The path calculation unit 13 calculates soft clauses (costs for vertical movement of transport shelves 22A and 22B, and horizontal movement of item 150) in addition to the constraints calculated as a SAT problem as described above.

[0066] The motion control unit 11 controls the transport operation of the item 150 based on the transport path information calculated in step S20 (step S30). This completes the control process shown in Figure 30.

[0067] Next, the operation and effects of the control device 10 and control method of the logistics warehouse 1 according to this embodiment will be described.

[0068] In the control device 10 of the logistics warehouse 1, the item information acquisition unit 12 acquires item information indicating the initial and completed states of item 150's movement when the item 150 moves in the order of receiving lane 21, conveyor 22, and automated warehouse 100, or when it moves in the order of automated warehouse 100, conveyor 22, and outbound lane 121. The route calculation unit 13 calculates transport route information from the item information so as to satisfy a standard logical formula based on constraints. In this case, the route calculation unit 13 can calculate what transport route the item 150 should take between its initial state and its completed state. At this time, the route calculation unit 13 can easily eliminate constraints on the transport route by calculating the standard logical formula so as to satisfy the standard logical formula based on constraints. As a result, the route calculation unit 13 can calculate an appropriate transport route with less computational load. Thus, the computational load when calculating the transport route for transporting item 150 can be reduced.

[0069] The path calculation unit 13 defines the constraints as a satisfactionability determination problem, and the base logic formula may include movement constraints regarding the movement of article 150, initial constraints regarding the initial state of article 150, and arrival constraints regarding the arrival of article 150 at its destination.

[0070] The conveyor 22 is a vertical conveyor that performs vertical conveyance by moving the goods 150 laterally while alternately raising and lowering the conveyor boxes 22a of adjacent conveyor shelves 22A and conveyor boxes 22a of conveyor shelf 22B. The path calculation unit 13 may perform calculations by considering the three phases of operation that enable the lateral movement of the goods 150, and one raising and lowering operation of the conveyor 22 as one step. Thus, due to the structure of the vertical conveyor, there are cases in which efficient movement is possible by making about three consecutive lateral movements, but no movement of goods occurs even if the raising and lowering operation is performed continuously. Therefore, by making the lateral movement into an appropriate number of phases, three, and the raising and lowering operation into one step, the path calculation unit 13 can easily calculate an efficient conveyance path.

[0071] The path calculation unit 13 may define the acquired multiple transport path information as a satisfaction maximization problem and calculate at least one of the following: a solution that satisfies all hard clauses and maximizes the sum of the weights of the satisfying soft clauses, and a solution that satisfies all hard clauses and minimizes the sum of the weights of the unsatisfied soft clauses. In this case, the path calculation unit 13 can select the transport path that satisfies the hard clauses and clears the necessary constraints, based on the weights of the soft clauses, which moves the goods most efficiently.

[0072] When items with the same floor number in the receiving lane 21 and the shipping lane 121, and the same floor number as the target position in the automated warehouse 100, pass through the conveyor 22 consecutively, the path calculation unit 13 may treat the consecutive items 150 as a single item (see Figure 21). For example, if there is a constraint on the number of consecutive lateral movements of an item 150, it is possible that the later item 150 among the consecutive items 150 may not be able to reach the target position. In contrast, by treating the consecutive items 150 as a single item, the path calculation unit 13 can ensure that the later item 150 also reaches the target position.

[0073] The control method for the logistics warehouse 1 includes: an item information acquisition step S10 that acquires item information indicating the initial state and completed state of movement of an item 150 when the item 150 moves in the order of receiving lane 21, conveyor 22, and automated warehouse 100, or when the item moves in the order of automated warehouse 100, conveyor 22, and outbound lane 121; a path calculation step S20 that calculates transport path information from the item information so as to satisfy a standard logical expression based on constraints; and a transport control step S30 that controls the transport operation of the item 150 based on the transport path information.

[0074] According to this control method for logistics warehouse 1, similar functions and effects as those of the control device 10 described above can be obtained.

[0075] Next, as described above, we will explain the processing method that can reduce the computational load while further improving transport efficiency by calculating transport path information to satisfy a standard logical formula based on constraints, with reference to Figures 31 to 43.

[0076] As described above, the control device 10 formulates the movement of the item 150 based on the basic operation concept of "3 phases and 1 step," as shown in Figure 31. Figure 31(a) shows two phases of leftward movement and one phase of rightward movement. Figure 31(b) shows one step of vertical movement. The part of the warehouse body 101 adjacent to the transport rack 22B becomes the goal position 120 for the item 150.

[0077] In addition to the above, the control device 10 is capable of performing the following calculations. First, the automated warehouse 100 is provided with a temporary placement area 125 adjacent to the conveyor 22. The temporary placement area 125 serves as the goal position 120 for the item 150 in Figure 31, and also as an area for temporarily placing the item 150 during its transport. As a result, as shown in Figure 32, the control device 10 enables the movement of the item 150 in "3 phases and 1 step" using the temporary placement area 125. As shown in Figure 32(a), it is possible to move two areas in one phase of rightward movement. The path calculation unit 13 calculates transport path information so as to satisfy a first standard logical expression regarding constraints on the entry of the item 150 into the temporary placement area 125, and a second standard logical expression regarding constraints on the movement of the item 150 into the temporary placement area 125. Hereafter, the formulation of the movement of the item 150, focusing on the movement to the temporary placement area 125, will be explained in detail.

[0078] [Variable definitions] This expresses the presence of item 150 at a given location in the temporary placement area 125. Equation (70) is a variable that indicates "the i-th item is on the j-th floor of the temporary placement area in phase p of step t". As shown in Figure 33, the temporary placement area 125 is represented as "buff". For the sake of formalization, the first floor of the temporary placement area 125 is represented as "j=0". That is, the temporary placement areas 125 on the first to fourth floors are represented as "buff0, buff1, buff2, buff3".

number

[0079] [Auxiliary Functions] Figure 33(a) shows the state where the left transport shelf 22B of the transporter 22 is raised. Figure 33(b) shows the state where the right transport shelf 22B of the transporter 22 is raised. When lateral movement occurs between the left transport shelf 22B of the transporter 22 and the temporary storage area 125, the floor after the movement changes depending on whether the left transport shelf 22B is down or up. Therefore, the floor after the movement is expressed in a simplified form. Equations (71) to (73) show the "floor of the temporary storage area that can be moved from the j-th floor of the left transport shelf at step t". Equations (74) to (76) show the "floor of the left transport shelf that can be moved from the j-th floor of the temporary storage area at step t". Note that when t is even, the state is as shown in Figure 33(a), and when t is odd, the state is as shown in Figure 33(b). This defines the floor of the temporary storage area 125 that can be moved from the vertical transporter.

[0080]

number

[0081] When lateral movement occurs between the right-hand transport rack 22A of the transporter 22 and the temporary storage area 125, the floor to which the movement occurs depends on whether the right-hand transport rack 22A is lowered or raised. Therefore, the floor to which the movement occurs is expressed in a simplified form. Equations (77) to (79) show the "floor level of the temporary storage area that can be reached from the j-th floor of the right-hand transport rack 22A at step t". Equations (80) to (82) show the "floor level of the right-hand transport rack that can be reached from the j-th floor of the temporary storage area at step t". Equation (83) shows the "floor level of the temporary storage area that can be reached from the receiving lane at step t".

number

[0082] As described above, the path calculation unit 13 calculates the transport path information by referring to the above equations (71) to (83) as reference theoretical equations (auxiliary logical equations) for the constraints on the transport rack 22B.

[0083] [Box constraints in the temporary placement area] Each transport box 22a in the temporary placement area can only contain one item 150. Equation (84) shows this constraint. Equation (85) explains t and p in equation (84).

number

[0084] [Constraints on the existence of goods] The constraint on the existence of item 150 is obtained by adding the temporary placement area 125 to the constraint (equation (18)) when the temporary placement area 125 is not considered. Equation (86) shows the constraint on the existence of item 150 when the temporary placement area 125 is considered. Equation (86) is interpreted as "At (t,p), item i is either lined up at the entrance, in a transport shelf, in a temporary placement area, or has reached the destination floor."

number

[0085] As described above, the route calculation unit 13 calculates transport route information to satisfy equations (84) to (86), which are first standard logical expressions relating to constraints on the loading of goods 150 into the temporary storage area 125.

[0086] [Auxiliary variables for existence constraints] A variable is prepared to represent whether item 150 exists in the left-hand transport rack 22B of the transport machine 22 at a location on the same floor as the entrance floor, which is the receiving lane 21 (the hatched location in Figures 34(a) and 34(b)). Equation (87) indicates that "in phase 2 of step t, the item exists at the same floor as the entrance floor in the left-hand transport rack." The hatched locations in Figures 34(a) and 34(b) indicate the locations to which the auxiliary variable applies. Using this auxiliary variable, equations (88) and (89) show, based on De Morgan's laws, that the item is in the transport box 22a, which is on the second floor of the entrance floor of the left-hand transport rack 22B. Equations (88) and (89) are constraints on the existence of item 150.

number

[0087] A variable is prepared to indicate whether item 150 is present in the temporary storage area 125. The grayed-out locations in Figures 34(a) and (b) indicate the locations to which the auxiliary variable applies. Equation (90) indicates that "an item is present in the temporary storage area in phase p of step t". Using this auxiliary variable, equations (91) and (92) show that items are present on each level of the temporary storage area 125, based on De Morgan's laws. Equations (91) and (92) are constraints on the presence of item 150.

number

[0088] [Entrance constraints] Basically, the same constraints are used for the entrance as when the temporary placement area 125 is not considered. However, different constraints are applied to the items 150 immediately following and after an item moving to the same destination floor as the entrance floor (item going to the second floor). First, the constraints applied to the item 150 immediately following the item 150 going to the second floor are shown. Equations (93) and (94) show the movement constraints for the item 150 immediately following in Phase 0. Equation (93) 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 either on the right-hand transport shelf at (t,1) or remains lined up at the entrance." Equation (94) is interpreted as, "If item i is lined up at the entrance at (t,0) and item i-1 is lined up at the entrance at (t,0), then item i remains lined up at the entrance at (t,1)." Equation (95) shows the immediate constraint for moving 150 items in Phase 1. Equation (95) is interpreted as "If item i is lined up at the entrance at (t,1), then item i remains lined up at the entrance at (t,2)." Equations (96) to (100) show the immediate constraint for moving 150 items in Phase 2. Equation (96) is interpreted as "If item i is lined up at the entrance at (t,2) and item i-1 is not lined up at the entrance at (t,0), then item i remains lined up at the entrance at (t+1,0)." Equation (97) is interpreted as "If item i is lined up at the entrance at (t,2), item i-1 is lined up at the entrance at (t,0), and item i-1 is on the target floor at (t+1,0), then at (t+1,0) item i is either on the left storage shelf, on the right transport shelf, in the temporary placement area, or remains lined up at the entrance." Equation (98) is interpreted as "If item i is lined up at the entrance at (t,2), item i-1 is lined up at the entrance at (t,0), and item i-1 is on the left storage shelf at (t+1,0), then item i is on the right transport shelf at (t+1,0) or remains lined up at the entrance." Equation (99) is interpreted as "If item i is lined up at the entrance at (t,2), item i-1 is lined up at the entrance at (t,0), and item i-1 is on the right storage shelf at (t+1,0), then item i remains lined up at the entrance at (t+1,0)." Equation (100) is interpreted as "If item i is lined up at the entrance at (t,2), and item i-1 is lined up at the entrance at (t,0), then item i remains lined up at the entrance at (t+1,0)."

number

[0089] Next, we show the constraints that apply to item 150 further behind. The movement constraints for item 150 further behind in Phase 0 are the same as equations (93) and (94). The movement constraints for item 150 further behind in Phase 1 are the same as equation (95). The movement constraints for item 150 further behind in Phase 2 are the same as equations (96), (98) to (100), except that equation (97) is changed to equation (101). Equation (101) is interpreted as "If item i is lined up at the entrance at (t,2), item i-1 is lined up at the entrance at (t,0), and item i-1 is in the temporary placement area at (t+1,0), then at (t+1,0), item i is either on the left storage shelf, on the right transport shelf, or still lined up at the entrance."

number

[0090] [Movement constraints on the conveyor shelf on the left side of the conveyor] This section describes the constraints when an item 150 moves from the left-hand transport rack 22B to its target floor. The difference from not considering the temporary placement area is the possibility that the item 150 is in the temporary placement area 125. First, we show the constraints when the i-th item 150 is in a position to move to the target floor within the left-hand transport rack 22B at step t, phase p. The positions subject to the constraints are those indicated by hatching in Figures 35(a) and (b). Equations (102) and (103) show the movement constraints in phase 0. Equation (102) is interpreted as, "When an item i in the transport box j of the left-hand transport rack transitions from (t,0) to (t,1), if the item was in the temporary placement area in phase 1, it will remain in the same transport box j." Equation (103) is interpreted as follows: "If item i is on the left storage shelf at (t,0) and there are no items in the temporary placement area at (t,1), then item i is either on the destination floor at (t,1) or remains on the left transport shelf." "When item i is in transport box j on the left transport shelf, if the temporary placement area is empty in phase 1 when transitioning from (t,0) to (t,1), it will either move to the destination floor or remain in the same transport box j." Equations (104) to (106) show the movement constraints in phases 1 and 2. Equation (104) is interpreted as follows: "When item i is in transport box j on the left transport shelf, if it is there in phase p-1 when transitioning from (t,p) to the next phase (t,p), it will remain in the same transport box j." Equation (105) is interpreted as "When item i in transport box j on the left transport rack transitions from (t,p) to the next phase next(t,p), if it is not there in phase p-1 and there is an item in the temporary storage area, it remains in the same transport box j." Equation (106) is interpreted as "When item i in transport box j on the left transport rack transitions from (t,p) to the next phase next(t,p), if it is not there in phase p-1 and the temporary storage area is empty, it either moves to the destination floor or remains in the same transport box j."

number

[0091] Next, the constraints for Phase 0 and Phase 1 are shown for the case where the i-th item 150 is not in a position to move to the target floor of the transport rack 22B in step t, phase p, and is not the entrance floor (2nd floor). The positions subject to the constraints are the positions shown by hatching in Figures 36(a) and (b). Equation (107) shows the movement constraints for item 150 in Phase 0. Equation (107) is interpreted as "When item i in transport box j of the transport rack on the left transitions from (t,0) to (t,1), it either moves to the temporary placement area or remains in the same transport box j." Equations (108) and (109) show the movement constraints for item 150 in Phase 1. Equation (108) is interpreted as "When item i in transport box j of the transport rack on the left transitions from (t,p) to the next phase next(t,p), if it was there in Phase p-1, it remains in the same transport box j." Equation (109) is interpreted as follows: "When item i in transport box j on the left transport rack transitions from (t,1) to (t,2), if it was not there in phase 0, it either moves to the temporary placement area or remains in the same transport box j."

number

[0092] The constraints on the floor corresponding to the entrance floor (2nd floor) are shown. The positions subject to the constraints are the positions indicated by hatching in Figures 37(a) and (b). In Phase 0, equation (107) is the movement constraint for item 150. In Phase 1, equations (108) and (109) are the movement constraints for item 150. In Phase 2, equations (108), (110), and (111) are the movement constraints for item 150. Equation (110) is interpreted as, "When item i in transport box j on the left transport shelf transitions from (t,2) to (t+1,0), if it was not there in Phase 1 and the temporary placement area is empty, it will either move to the temporary placement area or remain in the same transport box j." Equation (111) is interpreted as follows: "When item i in transport box j on the left transport rack transitions from (t,2) to (t+1,0), if it is not there in phase 1 and there is an item in the temporary placement area, it remains in the same transport box j."

number

[0093] [Movement constraints in temporary placement areas] Equation (112) shows the constraint when the i-th item 150 is in the temporary storage area 125 and is in a position to move to the target floor of the transport rack 22B in step t, phase p. Equation (112) is interpreted as "When item i, which is on the j-th floor of the temporary storage area, transitions from (t,p) to the next phase next(t,p), it moves to the target floor." The positions subject to the constraint are shown in gray in Figures 38(a) and (b). Equation (113) shows the constraint when the i-th item is in the temporary storage area 125 and is not in a position to move to the target floor of the transport rack 22B in step t, phase p, and the transport rack 22B on the left is raised and the temporary storage area 125 is on the lowest floor. The positions subject to the constraint are shown in gray in Figure 38(c). Equation (113) is interpreted as "When item i is on the jth floor of the temporary placement area, it remains on the same jth floor when transitioning from (t,p) to the next phase next(t,p)."

number

[0094] When the i-th item 150 is in the temporary storage area 126 and is not in a position to move to the target floor of the transport rack in step t, phase p, and the left lift of the transporter is raised and the temporary storage area is not the lowest floor, and it is phase 0 and phase 1, the constraint is given by equation (113). The positions subject to the constraint are those shown in gray in Figures 39(a) and (b). The constraints when it is phase 2, the right transport rack 22A is raised, and the temporary storage area 125 is the lowest floor are shown by equations (114) and (115). The positions subject to the constraint are those shown in gray in Figure 39(c). Equation (114) is interpreted as, "When item i on the j-th floor of the temporary storage area transitions from (t,2) to (t+1,0), if it was not there in phase 0, it remains on the j-th floor." Equation (115) is interpreted as follows: "When item i on the jth floor of the temporary storage area transitions from (t,2) to (t+1,0), if it was there in phase 0, it either moves to the storage shelf on the left or remains on the jth floor."

number

[0095] The constraints when Phase 2 and the temporary storage area is on the 3rd and 4th floors are shown in equations (114), (116), and (117). Equation (116) is interpreted as follows: "When item i on the jth floor of the temporary storage area transitions from (t,2) to (t+1,0), if it was there in Phase 0, and there is an item on the left storage shelf, it will either move to the left storage shelf or remain on the jth floor." Equation (117) is interpreted as follows: "When item i on the jth floor of the temporary storage area transitions from (t,2) to (t+1,0), if it was there in Phase 0, and the left storage shelf is empty, it will either move to the left storage shelf, move to the right storage shelf, or remain on the jth floor." The positions subject to the constraints are those shown in gray in Figures 40(a) and (b). The constraints when Phase 2 and temporary placement area 125 is on the entrance floor (2nd floor) are shown in equations (114), (115), (118) to (121). The locations subject to the constraints are shown in gray in Figures 40(c) and (d). By using the above movement constraints, it becomes possible to move items to temporary placement area 125. Equation (118) is interpreted as, "When item i on the jth floor of the temporary placement area transitions from (t,2) to (t+1,0), if it was there in Phase 0, if the storage shelf on the left is empty at (t+1,0), or if there is an item on the storage shelf on the left at (t,2), it will either move to the storage shelf on the left or remain on the jth floor." Equation (119) is interpreted as follows: "When item i on the jth floor of the temporary storage area transitions from (t,2) to (t+1,0), if it was there in phase 0, if the left storage shelf is empty at (t+1,0), if the left storage shelf is empty at (t,2), or if there is an item in the right storage shelf at (t,2), it will either move to the left storage shelf or remain on the jth floor." Equation (120) is interpreted as follows: "When item i on the jth floor of the temporary storage area transitions from (t,2) to (t+1,0), if it was there in phase 0, if the left storage shelf is empty at (t+1,0), if the left storage shelf is empty at (t,2), if the right storage shelf is empty at (t,2), or if there is an item in the right storage shelf at (t+1,0), it will either move to the left storage shelf or remain on the jth floor."Equation (121) is interpreted as follows: "When item i on the jth floor of the temporary storage area transitions from (t,2) to (t+1,0), if it was there in phase 0, and if the left storage shelf is empty at (t+1,0), if the left storage shelf is empty at (t,2), if the right storage shelf is empty at (t,2), or if the right storage shelf is empty at (t+1,0), it will either move to the right storage shelf, move to the left storage shelf, or remain on the jth floor."

number

[0096] As described above, the route calculation unit 13 calculates transport route information so as to satisfy the second standard logical formulas, equations (112) to (121), which are constraints on the movement of the article 150 to the temporary placement area 125.

[0097] [Soft clauses and related hard clauses] If the i-th item 150 is lined up in the receiving lane 21 at step t, phase 0, and is in the temporary placement area 125 at step t+1, phase 0, then the horizontal movement cost is 3. Constraints are shown in equation (122).

number

[0098] For the horizontal movement of an item 150 that moves immediately after a non-consecutive item 150 going to the second floor, we prepare equation (123). Equation (123) shows the horizontal movement cost of item 150, and we can set the "weight: 1" as in the case where we do not consider the temporary placement area 125. If the i-th item 150 is lined up in the receiving lane 21 at step t, phase 0, and is in the temporary placement area at step t+1, phase 0, the horizontal movement cost is 4. We then show constraints on equation (124).

number

[0099] Equation (125) is provided for the horizontal movement of 150 consecutive items going to the second floor. Equation (125) shows the horizontal movement cost of 150 items and is set to "weight: s-1". Here, s is the number of consecutive items 150. If the i-th item (an item consisting of multiple consecutive items) is lined up in the receiving lane 21 at step t, phase 0, and is at the target floor of the storage shelf in the warehouse main unit 101 at step t+1, phase 0, the horizontal movement cost is s+2. Relevant constraints are shown in equations (126) and (127). Equation (126) is set to "weight: s-1". Equation (127) shows that the "horizontal movement cost: s+3".

number

[0100] Equation (128) is prepared for the horizontal movement of item 150 immediately following a series of items 150 going to the second floor. Equation (128) shows the horizontal movement cost of item 150 and is set to "weight: 1". Here, s is the number of consecutive items 150. If the i-th item (an item that combines multiple consecutive items) is lined up in the receiving lane 21 at step t, phase 0, and the (i+1)th item 150 (the item immediately following the item that combines multiple consecutive items) is at the target floor of the storage shelf at step t+1, phase 0, the horizontal movement cost is s+3. Relevant constraints are shown for equations (129) and (130). Figure 41 shows the situation to which equations (129) and (130) apply. Here, there are three consecutive items 150 going to the second floor. Therefore, "s=3". The (i+1)th item 150 (the item immediately following the item that combines multiple consecutive items) is an item 150 going to the fourth floor. The path calculation unit 13 evaluates the number of horizontal movements using equations (129) and (130) for a situation where, after items 150 to be transported to the second floor are transported continuously, items 150 to be transported to the fourth floor move to the temporary placement area 125. Equation (129) is set to "weight: 1". Equation (130) indicates that a "horizontal movement cost: s + 3" is incurred.

number

[0101] If the i-th item 150 is on the right-hand transport rack 22A of the transporter 22 in step t, phase 0, and is in the temporary placement area in step t+1, phase 0, the horizontal movement cost is 2. The constraints in this case are shown in equation (131). The situation in which the number of horizontal movements is evaluated using equation (131) is shown in Figures 42(a) and (b). The path calculation unit 13 evaluates the number of horizontal movements using equation (131) for the situation in which the item 150 on the right-hand transport rack 22A moves to the temporary placement area 125.

number

[0102] If the i-th item 150 is on the left-hand transport rack 22B of the transporter 22 in step t, phase 0, and is in the temporary placement area 125 in step t+1, phase 0, then the horizontal movement cost is 1. The constraints in this case are shown by equation (132). The situation in which the number of horizontal movements is evaluated using equation (132) is shown in Figures 42(c) and (d). The path calculation unit 13 evaluates the number of horizontal movements using equation (132) for the situation in which item 150, which is on the left-hand transport rack 22B, moves to the temporary placement area 125.

number

[0103] If the i-th item 150 is in the temporary placement area 125 in step t, phase 0, and is on the left-hand transport rack 22B lift of the transporter 22 in step t+1, phase 0, the horizontal movement cost is 1. Constraints are shown in equation (133). The situation in which the number of horizontal movements is evaluated in equation (133) is shown in Figures 43(a) and (b). The path calculation unit 13 evaluates the number of horizontal movements in equation (133) for the situation in which item 150, which is in the temporary placement area 125, moves to the left-hand transport rack 22B.

number

[0104] If the i-th item 150 is in the temporary placement area 125 in step t, phase 0, and is on the right-hand transport rack 22A of the transporter 22 in step t+1, phase 0, the horizontal movement cost is 2. Constraints are shown in equation (134). The situation in which the number of horizontal movements is evaluated in equation (134) is shown in Figures 43(c) and (d). The path calculation unit 13 evaluates the number of horizontal movements in equation (134) for the situation in which item 150, which is in the temporary placement area 125, moves to the right-hand transport rack 22A.

number

[0105] Within the constraints described above, the route calculation unit 13 can calculate the transport route with the fewest number of operations while allowing movement to temporarily place the item in the temporary placement area 125. The route calculation unit 13 may search for transport route information that minimizes the horizontal (lateral) cost of the item 150.

[0106] As described above, the automated warehouse 100 is provided with a temporary storage area 125 adjacent to the conveyor 22. The route calculation unit 13 calculates transport route information so as to satisfy a first standard logical expression (e.g., expressions (84) to (86)) relating to constraints on the entry of goods 150 into the temporary storage area 125 and a second standard logical expression (e.g., expressions (112) to (121)) relating to constraints on the movement of goods 150 into the temporary storage area. In this way, the route calculation unit 13 can efficiently search for a transport route using the temporary storage area 125 by easily eliminating operations that are constrained in the transport route by using the first and second standard logical expressions. As a result, the computational load when calculating a transport route for transporting goods 150 can be reduced.

[0107] The conveyor 22 is a vertical conveyor that performs vertical conveyance by moving the items 150 laterally while alternately raising and lowering the conveyor rack 22B adjacent to the temporary placement area 125, and the conveyor rack 22A adjacent to the conveyor rack 22B. The path calculation unit 13 calculates conveyance path information by referring to auxiliary logical formulas (for example, formulas (71) to (83)) related to constraints on the conveyor rack 22B. As a result, the path calculation unit 13 can efficiently search for a conveyance path using the temporary placement area 125 while easily eliminating operations that are constrained in relation to the conveyor rack 22B by using a third reference logical formula.

[0108] The route calculation unit 13 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 150. In this case, the route calculation unit 13 can adopt the transport route that moves the item 150 most efficiently based on the cost of its lateral movement.

[0109] The present invention is not limited to the embodiments described above.

[0110] The SAT problem and the various constraints of MaxSAT described above are merely examples and can be modified as appropriate. Furthermore, the number of floors in the automated warehouse 100, the conveyors 22, the receiving lane 21, and the shipping lane 121 can also be changed as appropriate, and the constraints may be modified accordingly.

[0111] For example, the logistics warehouse is not limited to the one shown in Figure 1. For instance, multiple automated warehouses may be provided in parallel for a pair of receiving lanes 21 and shipping lanes 121. Also, the conveyor does not have to be of the type of vertical conveyor with a pair of storage shelves that move up and down alternately, as shown in Figure 2. For example, a rotary conveyor (a conveyor in which storage shelves move in a circular motion one level at a time in a constant direction, and when the storage shelves are not moving in a circular motion, goods can move between the storage shelves) may be used. In addition, escalator-type and traction-type conveyors may be used. In this case, the control device only needs to calculate the conveying path information so as to satisfy a standard logical formula based on the constraints of the conveyor.

[0112] [Form 1] An automated warehouse for storing goods, A transport lane for transporting multiple items arranged in a line, A control device for a logistics warehouse, comprising a conveyor installed between the conveyor lane and the automated warehouse, When the article moves in the order of the transport lane, the transport machine, and the automated warehouse, an article information acquisition unit acquires article information indicating the initial state and completed state of the article's movement. A path calculation unit calculates transport path information from the aforementioned item information so as to satisfy a standard logical formula based on constraints, The system includes an operation control unit that controls the transport operation of the logistics warehouse based on the transport route information, The automated warehouse is provided with a temporary storage area adjacent to the conveyor, The aforementioned path calculation unit, A first standard logical formula relating to constraints on the storage of the items in the temporary storage area, A control device for a logistics warehouse that calculates the transport route information such that it satisfies a second standard logical formula relating to constraints on the movement of the items to the temporary placement area. [Form 2] The conveying machine is a vertical conveying machine that performs vertical conveying by moving the articles laterally while alternately raising and lowering a first conveying shelf adjacent to the temporary placement area and a second conveying shelf adjacent to the first conveying shelf. The path calculation unit performs calculations by considering the three phases of movement that enable the lateral movement of the article, and one lifting and lowering movement of the conveyor as one step. A control device for a logistics warehouse according to Embodiment 1, wherein the hierarchy of the temporary placement area that is movable from the vertical conveyor is defined. [Form 3] The conveying machine is a vertical conveying machine that performs vertical conveying by moving the articles laterally while alternately raising and lowering a first conveying shelf adjacent to the temporary placement area and a second conveying shelf adjacent to the first conveying shelf. The control device for a logistics warehouse according to Embodiment 1 or 2, wherein the route calculation unit calculates the transport route information by referring to an auxiliary logical expression relating to constraints on the first transport shelf. [Form 4] The aforementioned path calculation unit, The multiple transport path information obtained is defined as a sufficiency maximization problem, A control device for a logistics warehouse according to any one of the embodiments 1 to 3, which searches for transport route information that minimizes the lateral cost of the aforementioned articles. [Explanation of Symbols]

[0113] 1...Logistics warehouse, 10...Control device, 12...Item information acquisition unit, 13...Route calculation unit, 21...Inbound lane (transport lane), 22...Transport machine, 22A...Transport shelf (second transport shelf), 22B...Transport shelf (first transport shelf), 100...Automated warehouse, 121...Outbound lane (transport lane), 150...Items.

Claims

1. An automated warehouse for storing goods, A transport lane for transporting multiple items arranged in a line, A control device for a logistics warehouse, comprising a conveyor installed between the conveyor lane and the automated warehouse, When the article moves in the order of the transport lane, the transport machine, and the automated warehouse, an article information acquisition unit acquires article information indicating the initial state and completed state of the article's movement. A path calculation unit calculates transport path information from the aforementioned item information so as to satisfy a standard logical formula based on constraints, The system includes an operation control unit that controls the transport operation of the logistics warehouse based on the transport route information, The automated warehouse is provided with a temporary storage area adjacent to the conveyor, The aforementioned path calculation unit, A first standard logical formula relating to constraints on the storage of the articles in the temporary storage area, A control device for a logistics warehouse that calculates the transport route information such that it satisfies a second standard logical formula relating to constraints on the movement of the items to the temporary placement area.

2. The conveying machine is a vertical conveying machine that performs vertical conveying by moving the articles laterally while alternately raising and lowering a first conveying shelf adjacent to the temporary placement area and a second conveying shelf adjacent to the first conveying shelf. The path calculation unit performs calculations by considering the three phases of movement that enable the lateral movement of the article, and one lifting and lowering movement of the conveyor as one step. The control device for a logistics warehouse according to claim 1, wherein the hierarchy of the temporary placement area that is movable from the vertical conveyor is defined.

3. The conveying machine is a vertical conveying machine that performs vertical conveying by moving the articles laterally while alternately raising and lowering a first conveying shelf adjacent to the temporary placement area and a second conveying shelf adjacent to the first conveying shelf. The control device for a logistics warehouse according to claim 1, wherein the route calculation unit calculates the transport route information by referring to an auxiliary logical expression relating to constraints on the first transport shelf.

4. The aforementioned path calculation unit, The multiple transport path information obtained is defined as a sufficiency maximization problem, A control device for a logistics warehouse according to claim 1, which searches for transport route information that minimizes the lateral cost of the article.

Images