JP7627465B2 - Control device for logistics warehouse and control method for logistics warehouse - Google Patents

Description

The present invention relates to a control device for a logistics warehouse and a control method for a logistics warehouse.

Conventionally, a logistics warehouse for storing items is known, for example, as described in Patent Document 1. This logistics warehouse carries in items via a transport lane and stores them in an automated warehouse. This logistics warehouse also transports and removes items stored in the automated warehouse at a specified time.

JP 2018-81008 A

A large number of items are stored in the automated warehouse. Therefore, the control device needs to calculate efficient transport routes when storing and retrieving items. However, there is a problem with calculating such transport routes, in that the calculation load becomes enormous.

The present invention therefore aims to provide a control device for a logistics warehouse and a control method for a logistics warehouse that can reduce the computational load when calculating a transport route for transporting goods.

A control device for a logistics warehouse according to one aspect of the present invention is a control device for a logistics warehouse that includes an automated warehouse for storing items, a transport lane for transporting a plurality of lined up items, and a transport machine provided between the transport lane and the automated warehouse, and includes an item information acquisition unit that acquires item information indicating an initial state and a completed state of the item when the item moves in the order of the transport lane, the transport machine, and the automated warehouse, or when the item moves in the order of the automated warehouse, the transport machine, and the transport lane, a route calculation unit that calculates transport route information from the item information so as to satisfy a reference logical expression based on a constraint condition, and an operation control unit that controls the transport operation of the logistics warehouse based on the transport route information.

In the control device for the logistics warehouse, the item information acquisition unit acquires item information indicating the initial movement state and the completed movement state of the item when the item moves in the order of the transport lane, the transport machine, and the automated warehouse, or when the item moves in the order of the automated warehouse, the transport machine, and the transport lane. The path calculation unit calculates transport path information from the item information so as to satisfy a reference logical formula based on the constraint conditions. In this case, the path calculation unit can calculate what transport path the item should take between the initial movement state and the completed item state. At this time, the path calculation unit calculates so as to satisfy the reference logical formula based on the constraint conditions, and can easily eliminate operations that are restricted in the transport path by calculating the reference logical formula. As a result, the path calculation unit can calculate an appropriate transport path with a small calculation load. As a result, the calculation load when calculating a transport path for transporting items can be reduced.

The path calculation unit defines the constraint conditions as a satisfiability problem, and the reference formula may include movement constraints on the movement of the item, initial constraints on the initial state of the item, and arrival constraints on the arrival of the item at the destination.

The conveyor is a vertical conveyor that performs vertical conveyance by moving items horizontally while alternately raising and lowering multiple adjacent conveyor boxes, and the path calculation unit may perform calculations using a three-phase operation that allows items to move horizontally, and one lifting and lowering operation of the conveyor as one step. In this way, due to the structure of the vertical conveyor, there are cases where efficient movement is possible by performing about three consecutive horizontal movements, but consecutive lifting and lowering operations do not result in movement of items. Therefore, the path calculation unit makes it easier to calculate an efficient conveyance path by dividing the horizontal movement into an appropriate number of phases, such as three, while treating the lifting and lowering operation as one step.

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

When items whose number of floors of the conveyor lane and whose target position in the automated warehouse are the same pass through the conveyor in succession, the path calculation unit may treat the consecutive items as a single item. For example, if there is a restriction on the number of consecutive lateral movements of an item, there is a possibility that the rear item of the consecutive items will not be able to reach the target position as it is. In response to this, the path calculation unit can treat the consecutive items as a single item, allowing the rear item to reach the target position as it is.

A method for controlling a logistics warehouse according to one aspect of the present invention is a method for controlling a logistics warehouse that includes an automated warehouse for storing items, a transport lane for transporting a plurality of items arranged in a predetermined order, and a transport machine provided between the transport lane and the automated warehouse, and includes an item information acquisition step for acquiring item information indicating an initial state and a completed state of the movement of the item when the item moves in the order of the transport lane, the transport machine, and the automated warehouse, or when the item moves in the order of the automated warehouse, the transport machine, and the transport lane, a route calculation step for calculating transport route information from the item information so as to satisfy a reference logical formula based on a constraint condition, and a transport control step for controlling the transport operation of the item based on the transport route information.

This logistics warehouse control method can achieve the same effects and benefits as the control device described above.

The present invention can reduce the computational load when calculating a transport path for transporting items.

1 is a schematic side view showing a logistics warehouse equipped with a control device according to an embodiment of the present invention. 1 is a schematic diagram showing a configuration of a logistics warehouse according to an embodiment of the present invention; This is a diagram showing a model of a logistics warehouse. FIG. 2 is a block diagram of a control device according to the present embodiment. This is a diagram showing a model of a logistics warehouse. This is a diagram showing a model of a logistics warehouse. FIG. 11 is a diagram illustrating the specific content of a logical expression. FIG. 11 is a diagram illustrating the specific content of a logical expression. FIG. 11 is a diagram illustrating the specific content of a logical expression. 1A is a diagram showing the relationship between phases and movement directions, and FIG. 1B is a diagram showing a model of a logistics warehouse. 1A is a diagram illustrating a specific example of a logical expression, and FIGS. 1B and 1C are diagrams illustrating a model of a logistics warehouse. 1A is a diagram illustrating a specific example of a logical expression, and FIGS. 1B and 1C are diagrams illustrating a model of a logistics warehouse. This is a diagram showing a model of a logistics warehouse. 1A is a diagram illustrating a specific example of a logical expression, and FIGS. 1B and 1C are diagrams illustrating a model of a logistics warehouse. This is a diagram showing a model of a logistics warehouse. 1A is a diagram illustrating a specific example of a logical expression, and FIGS. 1B and 1C are diagrams illustrating a model of a logistics warehouse. 1A is a diagram illustrating a specific example of a logical expression, and FIGS. 1B and 1C are diagrams illustrating a model of a logistics warehouse. 1A is a diagram illustrating a specific example of a logical expression, and FIGS. 1B and 1C are diagrams illustrating a model of a logistics warehouse. This is a diagram showing a model of a logistics warehouse. This is a diagram showing a model of a logistics warehouse. This is a diagram showing a model of a logistics warehouse. FIG. 11 is a diagram illustrating the specific content of a logical expression. FIG. 11 is a diagram illustrating the specific content of a logical expression. FIG. 11 is a diagram illustrating the specific content of a logical expression. This is a diagram showing a model of a logistics warehouse. This is a diagram showing a model of a logistics warehouse. FIG. 11 is a diagram illustrating the specific content of a logical expression. This is a diagram showing a model of a logistics warehouse. FIG. 11 is a diagram illustrating the specific content of a logical expression. 4 is a flowchart showing the processing contents of the control device.

The following describes an embodiment of the present invention in detail with reference to the drawings.

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

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 outgoing 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 outgoing side of the logistics warehouse 1 has the same configuration as the receiving side except that the flow of the goods 150 flows through the automated warehouse 100, the conveyor 22 (outgoing elevator 104), and the outgoing lane 121, so the description will be omitted. As shown in Figure 2, the logistics warehouse 1 includes a conveyor system 2 that conveys the goods 150 and a control device 10 that controls the conveyor system 2. The conveyor system 2 includes the receiving lane 21, the conveyor 22, and the conveyor 23 of the automated warehouse 100. Of these, the conveyor 22 is a device that constitutes the above-mentioned receiving elevator 105. The receiving lane 21 is a device that conveys the goods 150 horizontally and transfers them to the conveyor 22. The receiving lane 21 is provided for a specific stage of the conveyor 22. The conveyor 23 is a device that receives items from the conveyor 22 and conveys them horizontally on each floor of the automated warehouse 100. The conveyor 23 is provided on each floor (here, the fourth floor) of the receiving walkway 103.

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

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

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

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

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

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

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

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

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

The route calculation unit 13 also defines the multiple transport route information acquired as a Maximum Satisfaction Problem (MaxSAT problem). The MaxSAT problem is a problem of finding a variable ratio that maximizes the number of satisfied clauses for a set of clauses given as input. The MaxSAT problem is solving an optimization problem, that is, finding an optimal solution that satisfies constraints. For example, in response to the question, "What is the shortest time for all 150 items to arrive at the destination floor?", the answer is "10 seconds. The specific schedule is...". The route calculation unit 13 calculates at least one of a solution that satisfies all hard clauses and maximizes the sum of the weights of the satisfied soft clauses, and a solution that satisfies all hard clauses and minimizes the sum of the weights of the unsatisfied soft clauses. A hard clause is a clause that must be satisfied. A soft clause is one that you want to be filled as much as possible, and the degree to which it is filled is expressed as a weight (a positive integer).

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

Equation (3) and equation (6) are interpreted as "If all of _a1 to _am are true in the current state, then any of _c1 to _cn must be true." Using equation (3) and equation (6), for example, it is possible to show that "If an item is at XX on the right transport shelf (representing each a), in the next state, it will stay there or be at YY on the left transport shelf (representing each c)." Equation (4) is interpreted as "Of _l1 to _ln , at most one is True." If all _l1 to _ln are False, the left side of equation (4) is "0." That is, the left side of equation (4) is "1" or "0." Using equation (4), for example, it is possible to show that "At most one item is placed in each transport box (each transport box represents l) on the transport shelf." This means that the same item 150 cannot be present in the same transport box 22a at the same time. If an item 150 does not fit into any of the transport boxes 22a, the left side of formula (4) is "0". Formula (5) is interpreted as "exactly one of _l1 to _ln is True". Using formula (5), it is possible to express, for example, that "an item is always present in either the storage lane, the transport shelf, or the destination floor (each location represents l)". In the following description, when the term "entrance" is used to explain the constraint conditions, it means the storage lane 21. Furthermore, when the term "baggage" is used to explain the constraint conditions, it means the item 150.

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

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

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

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

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

[Luggage presence constraints]
The constraint condition regarding the presence of luggage somewhere in the transport system 2 will be explained. The reference logical formula includes the logical formula of formula (18) which indicates the presence constraint regarding the presence of luggage while the luggage is moving as a movement constraint. Formula (18) is interpreted as "at (t, p), luggage i is either lined up at the entrance, in a transport rack, or has reached the destination floor." Formula (19) indicates the range of values that (t, p) can take.

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

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

[Movement constraints (entrance)]
The constraint conditions for the movement of luggage when luggage is lined up at the entrance will be described. The reference logical formula includes the logical formula (24) which indicates the movement constraint of luggage on the entrance side as the movement constraint. The formula (24) is interpreted as "if luggage i is lined up at the entrance at (t, p), then in the next phase next(t, p), it will be on the transport shelf on the right side or will remain lined up at the entrance." The specific content of the formula (24) is shown in FIG. 8(b).

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

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

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

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

The reference logical formula includes, as a movement constraint, the logical formulas of formula (33), formula (34), and formula (35) which indicate the movement constraint of the luggage placed in the transport box of the left transport shelf 22B at the destination floor. Formula (33) is interpreted as "when the luggage i in the transport box j of the left transport shelf 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 the luggage i in the transport box j of the left transport shelf 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 "when a transition occurs from (t, 1) to (t, 2) or from (t, 2) to (t+1, 0), if the package i in the box j on the left-side transport shelf was not there immediately before, it moves to the left or remains in the same box j." When t is an even number, as shown in FIG. 15(a), the box 22a with the "identification number 0, 1, 2" on the left-side transport shelf 22B corresponds to the box 22a stopped at the target floor. When t is an odd number, as shown in FIG. 15(b), the box 22a with the "identification number 0, 1, 2, 3" on the left-side transport shelf 22B corresponds to the box 22a stopped at the target floor.

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

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

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

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

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

[Initial and arrival constraints]
The initial constraint will be described. The following (46) is True because it indicates that "all baggage is initially lined up at the entrance." The arrival constraint will be described. The following (47) is True because it indicates that "after M up-down movements of the transport rack, all baggage must have arrived at the destination floor."

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

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

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

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

[Optimal solution search possible with SAT]
Next, the unique optimal solution search of SAT will be explained. Let "S _M " be "a set of constraints (clauses) obtained when M is given." If S _M has a "solution," it can be interpreted as "all packages can reach the destination floor within M up and down movements of the rack." If S _M has a "no solution," it can be interpreted as "all packages will not reach the destination floor within M up and down movements of the rack." For example, if "S ₀ , S ₁ , ... S _m-1 " has "no solution" and "S _m , ..." has "a solution," then "m" is the optimal value.

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

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

The variable in (56) above will be explained. This variable is used in a negative form as shown in (58). (58) indicates the cost of horizontal movement of luggage, and "weight: 1" can be set. Equation (59) is interpreted as "during the transition from (t, 0) to (t, 1) to (t, 2) to (t+1, 0), no horizontal movement of luggage is performed."

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

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

Regarding horizontal movement from the entrance, formula (62) holds. Formula (62) is interpreted as "if baggage i is lined up at the entrance at (t, 0) and arrives at the destination floor at the next step (t+1, 0), the horizontal movement cost is 3." A specific example of formula (62) is shown in FIG. 23(b).

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

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

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

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

Regarding horizontal movement when multiple pieces of luggage are consecutively traveling from the entrance to the destination floor on the second floor (the situation shown in FIG. 21 above), a variable (67) is prepared. This variable is set to "weight: s-1", where s is the number of consecutive pieces of luggage. Furthermore, equations (68) and (60) hold true. "Luggage i" is a bundle of multiple consecutive pieces of luggage. Equations (68) and (69) are interpreted as "the horizontal movement cost of s consecutive pieces of luggage going to the second floor is S+2". Equation (68) is set to "weight: s-1", and equation (69) is set to "weight: 3".

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

At this time, the route calculation unit 13 calculates whether the schedule can be performed with the up-down movement of the transport shelves 22A and 22B M times or less as a SAT problem. The route calculation unit 13 calculates the reference logical formula to include a movement constraint regarding the movement of the item 150, an initial constraint regarding the initial state of the item 150, and an arrival constraint regarding the arrival of the item 150 at the destination. In other words, the route calculation unit 13 calculates the transport route information to satisfy the reference logical formula based on the basic constraints (entrance, destination floor, lift box, and presence of luggage) and the movement constraint (entrance → transport shelf → movement to destination floor). Furthermore, the route calculation unit 13 calculates the multiple transport route information obtained as a MaxSAT problem. The route calculation unit 13 calculates at least one of a solution that satisfies all hard clauses and maximizes the sum of 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 the soft clauses (the cost of vertical movement of the transport shelves 22A and 22B and the horizontal movement of the item 150) in addition to the constraints calculated as the above-mentioned SAT problem.

The operation 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 FIG. 30.

Next, we will explain the operation and effects of the control device 10 and control method of the logistics warehouse 1 according to this embodiment.

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

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

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

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

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

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

This control method for the logistics warehouse 1 can achieve the same effects and advantages as the control device 10 described above.

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

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

For example, the logistics warehouse is not limited to the one shown in FIG. 1. For example, multiple parallel automated warehouses may be provided for a pair of incoming lanes 21 and outgoing lanes 121. Furthermore, the conveyor does not have to be a vertical conveyor with a pair of storage shelves that move up and down alternately as shown in FIG. 2. For example, a rotary type conveyor (a conveyor in which the storage shelves move in a fixed direction one level at a time and in which articles can be moved between the storage shelves when the storage shelves do not move in a circular motion) may be used. Alternatively, an escalator type or traction type conveyor may be used. In this case, the control device may calculate the conveyor route information so as to satisfy a reference logical expression based on the constraint conditions applicable to the conveyor.

Reference Signs List 1: logistics warehouse, 10: control device, 12: item information acquisition unit, 13: route calculation unit, 21: storage lane (transport lane), 22: transport machine, 100: automated warehouse, 121: delivery lane (transport lane), 150: item.

Claims (6)

An automated warehouse for storing items;
A conveying lane for conveying a plurality of the arranged articles;
A control device for a logistics warehouse comprising a conveyor provided between the conveying lane and the automated warehouse,
an item information acquisition unit that acquires item information indicating an initial movement state and a movement completion state of the item when the item moves in the order of the transport lane, the transport machine, and the automated warehouse, or when the item moves in the order of the automated warehouse, the transport machine, and the transport lane;
a route calculation unit that calculates transport route information from the item information so as to satisfy a reference logical expression based on a constraint condition;
and an operation control unit that controls the transport operation of the logistics warehouse based on the transport route information. The path calculation unit defines the constraint condition as a satisfiability determination problem;
The control device for a logistics warehouse according to claim 1 , wherein the criteria formula includes a movement constraint regarding the movement of the item, an initial constraint regarding an initial state of the item, and an arrival constraint regarding the arrival of the item at a destination. The conveyor is a vertical conveyor that vertically conveys the articles by moving the articles in a lateral direction while alternately raising and lowering adjacent conveying boxes,
3. The control device for a logistics warehouse according to claim 1 or 2, wherein the path calculation unit performs calculations by considering three-phase operation that enables the item to move in the lateral direction and one lifting and lowering operation of the conveyor as one step. The path calculation unit is
The plurality of pieces of transportation route information obtained are defined as a satisfiability maximization problem;
A solution that satisfies all hard clauses and maximizes the sum of the weights of the soft clauses it satisfies.
and calculating at least one of a solution that satisfies all hard clauses and minimizes the sum of weights of unsatisfied soft clauses. The control device for a logistics warehouse according to any one of claims 1 to 4, wherein when items whose number of floors of the transport lane and whose number of floors of the target position in the automated warehouse are the same pass through the transport machine in succession, the path calculation unit regards the consecutive multiple items as one item. An automated warehouse for storing items;
A transport lane for transporting a plurality of the items arranged in a predetermined order;
A control method for a logistics warehouse including a conveyor provided between the conveying lane and the automated warehouse,
an item information acquisition step of acquiring item information indicating an initial movement state and a movement completion state of the item when the item moves in the order of the transport lane, the transport machine, and the automated warehouse, or when the item moves in the order of the automated warehouse, the transport machine, and the transport lane;
a route calculation step of calculating transport route information from the item information so as to satisfy a reference logical expression based on a constraint condition;
A control method for a logistics warehouse, comprising: a transport control step of controlling a transport operation of the item based on the transport route information.

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