DELIVERY SYSTEM, DELIVERY METHOD, NON-TRANSITORY COMPUTER READABLE MEDIUM

A delivery system includes a storage shelf, a delivery robot capable of moving to the storage shelf and delivering an article to the storage shelf, a detection unit that detects an obstacle present near the storage shelf, and a control unit that controls an operation of the delivery robot. The control unit is configured to, when the detection unit detects an obstacle present in a predetermined area near the storage shelf and the control unit determines that the delivery robot can deliver an article to the storage shelf, determine a stop position and a stop direction of the delivery robot relative to the storage shelf based on a position of the detected obstacle and a position of the storage shelf.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from Japanese patent application No. 2023-067819, filed on Apr. 18, 2023, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND

The present disclosure relates to a delivery system, a delivery method, and a program.

Japanese Unexamined Patent Application Publication No. 2022-061816 discloses a technology in which when a vehicle, such as an automated guided vehicle (AGV), delivers a package to a locker of an end user, the vehicle stores the package in the locker.

SUMMARY

When a delivery robot stores an article in a storage shelf, the delivery robot needs to stop in a predetermined area near the storage shelf. However, when an obstacle is present in the predetermined area near the storage shelf, the delivery robot may not be able to determine an appropriate stop position in the predetermined area near the storage shelf. Therefore, the delivery robot cannot execute an operation for storing the article in the storage shelf.

The present disclosure has been made in view of the above-described problem and provides a delivery system capable of delivering an article to a storage shelf and storing it in the storage shelf as much as possible without having to remove an obstacle present in a predetermined area in front of the storage shelf.

A delivery system according to one aspect of the present disclosure includes:a storage shelf;a delivery robot capable of moving to the storage shelf and delivering an article to the storage shelf;a detection unit configured to detect an obstacle present near the storage shelf; anda control unit configured to control an operation of the delivery robot,in which the control unit is configured to, when the detection unit detects an obstacle present in a predetermined area near the storage shelf and the control unit determines that the delivery robot is able to deliver an article to the storage shelf, determine a stop position and a stop direction of the delivery robot relative to the storage shelf based on a position of the detected obstacle and a position of the storage shelf, and then stop the delivery robot at the determined stop position in the determined stop direction to store the article in the storage shelf.

A delivery method according to one aspect of the present disclosure includes, when a detection unit detects an obstacle present in a predetermined area near a storage shelf and it is determined that a delivery robot is able to deliver an article to the storage shelf, determining a stop position and a stop direction of the delivery robot relative to the storage shelf based on a position of the detected obstacle and a position of the storage shelf, and then stopping the delivery robot at the determined stop position in the determined stop direction to store the article in the storage shelf.

A program according to one aspect of the present disclosure causes a computer to, when a detection unit detects an obstacle present in a predetermined area near a storage shelf and it is determined that a delivery robot is able to deliver an article to the storage shelf, determine a stop position and a stop direction of the delivery robot relative to the storage shelf based on a position of the detected obstacle and a position of the storage shelf, and then stop the delivery robot at the determined stop position in the determined stop direction to store the article in the storage shelf.

According to the present disclosure, it is possible to provide a delivery system and the like capable of delivering an article to a storage shelf and storing it in the storage shelf as much as possible without having to remove an obstacle present in a predetermined area in front of the storage shelf.

DESCRIPTION OF EMBODIMENTS

Specific embodiments to which the present disclosure is applied will be described hereinafter in detail with reference to the drawings. However, the present disclosure is not limited to the following embodiments. Further, for the clarification of the description, the following descriptions and the drawings are simplified as appropriate.

First Embodiment

A delivery system according to a first embodiment will be described below with reference to the drawings.

FIG.1is a schematic perspective view for explaining an outline of a delivery system1. The delivery system1can be used for a last one mile in logistics, that is, a logistics service from a final base to an end user. The delivery system1includes a delivery robot10and a storage shelf30. The storage shelf30, which is also referred to as a smart post, allows a delivery robot to complete delivery without having to hand an article to an end user. For example, the storage shelf is installed in each room of an apartment building where end users live. A resident (an end user) can access an article stored in the storage shelf from inside the room, and take an article out of the storage shelf or put an article into the storage shelf.

The delivery robot10moves to a plurality of storage shelves30disposed at various places, stops in front of each of the storage shelves30, and stores an article20in each of the storage shelves30. This operation can also be referred to as delivery. Further, the delivery robot10moves to a plurality of storage shelves30disposed at various places, stops in front of each of the storage shelves30, and takes the article20out of the storage shelf30, and conveys the article20taken out. This operation can also be referred to as a pickup. The delivery robot10(or the storage shelf30) includes a mechanism for delivering articles to and from the storage shelf30. The delivery robot10also includes various types of sensors, and it can detect storage shelves, roads, and obstacles, and move autonomously. A known object recognition technique can be used. The present disclosure proposes a delivery system and a delivery method capable of performing delivery as much as possible even when an obstacle is present near a storage shelf.

The storage shelf30may include a plurality of shelves (not shown) capable of housing articles. The storage shelf30, for example, is disposed in front of each room of a building or an apartment building, and includes a door (not shown) on the front surface thereof. The door can be opened automatically when the delivery robot10stops in front of the storage shelf30. The door may be, for example, a horizontally openable shutter, a vertically openable shutter, a single swing door, or a double swing door.

The delivery robot10includes a base part11including a plurality of wheels13(may be collectively referred to as a carriage part130), a storage part12provided on the base part11and in which a large number of articles20can be stored, and a mounting table15which is provided on the base part11and on which each of the articles20is mounted. The base part11may be a substantially rectangular elongated plate-like member. Further, one or more sensors18that detect or capture an image of an object or the like present in all directions of the delivery robot and detect a position of an obstacle on a road, a position of a storage shelf, or the like are provided at any place in the delivery robot10(the base part11in this example). The sensor18may be, for example, a camera. In some embodiments, for example, a traveling robot60(seeFIG.8) including a sensor (e.g., a sensor18such as a camera) that travels through an apartment building or another delivery robot including a sensor that performs another delivery may be provided separately from the delivery robot10. The traveling robot60may, for example, move through a passage in an apartment building and monitor whether or not obstacles are present on the passage. The traveling robot60can communicate monitoring information to the delivery robot through a wireless network. In another embodiment, a fixed monitoring camera70(a sensor18) (seeFIG.8) installed near the storage shelf30(e.g., the ceiling of a passage in an apartment building) may be provided.

The mounting table15includes a mechanism for mounting one article20taken out of the storage part12and storing this article20on one desired shelf of the storage shelf30. Further, the mounting table15can be moved up and down along a vertical direction, and includes an extendable arm (not shown) which can be extended and contracted on a horizontal direction axis, and the extendable arm is configured so as to be movable in the front-rear and right-left directions. In some embodiments, the mounting table15may be configured so as to be rotatable about a vertical axis. The mounting table15may also be configured so as to be movable in all directions) (360° in a state in which an article is mounted thereon. However, as shown inFIG.1, since the storage part12is disposed on one side of the base part11, the mounting table15cannot be moved in a certain direction of the storage part12(also referred to as a rear side in this specification). Note that the delivery robot30is used to deliver articles to and from the storage shelf30, and does not include a mechanism for removing obstacles.

Note that the delivery system1may include a management server (not shown) that controls the travelling of the delivery robot10. In this case, the management server includes a control unit100connected to the delivery robot through a network. Further, in another embodiment, the control unit of the management server and the control unit of the delivery robot can achieve the present disclosure by distributing the functions thereof.

FIG.2is a block diagram for explaining functions of the delivery system. The delivery system1includes the control unit100. The control unit100may be provided in the delivery robot10or a management server. The control unit100receives a sensor signal from the sensor18connected thereto through a wired or wireless network and controls a normal operation of the delivery system that includes the delivery robot including the carriage part130, an elevating part151, an extendable arm152, and the like. In some embodiments, the control unit100can control a door on the front surface of the storage shelf and an operation of a manipulator provided inside the door.

The carriage part130includes the base part11, the driving wheels13rotatably provided in the base part11, and motors1301that rotatably drive the respective driving wheels13. Each of the motors1301rotates a respective one of the driving wheels13through a speed reducer or the like. Each of the motors1301rotates a respective one of the driving wheels13in accordance with a control signal sent from the control unit100. Each of the motors1301rotates a respective one of the driving wheels13in accordance with a control signal sent from the control unit100, thereby enabling the base part11to move to any position. Note that the above-described configuration of the carriage part130is merely an example, and the configuration of the carriage part130is not limited to this example. For example, the number of driving wheels of the carriage part130and the number of driven wheels of the carriage part130may be any number, and any configuration in which the base part11can be moved to any position can be used.

The mounting table15moves up and down by the elevating part151extending and contracting along the vertical axis. The elevating part151includes a rotating apparatus1511. The extendable arm152is attached to the mounting table15. The extendable arm152includes an arm body and a driving apparatus1521. The driving apparatus1521, which is attached to an internal part (not shown) of the mounting table15, moves the arm body in the horizontal direction. The driving apparatus1521may further include a mechanism that rotates the arm body around the axis.

The sensor18is provided at any place in the delivery robot10including the carriage part130and the like. The sensor18is also referred to as a detection unit, and is, for example, a camera and can acquire captured images. The sensor18can detect the presence of passages, obstacles, people, storage shelves, and the like. The sensor18may include a movement detection sensor that detects movement of the carriage part130and a height detection sensor that detects a height of the mounting table15. In some embodiments, the sensor18may be attached to another traveling robot instead of a delivery robot, or may be fixed to a building or the like. In this case, like in the above case, the sensor18may be connected to the control unit100of the delivery robot10through a wireless network.

The control unit100controls a normal operation of the delivery system that includes the delivery robot including the carriage part130, the elevating part151, the extendable arm152, and the like. The control unit100can control the rotation of each of the driving wheels13and move the base part11to any position by transmitting a control signal to each of the motors1301of the carriage part130. The control unit100can change a height position of the mounting table15by transmitting a control signal to the rotating apparatus1511of the elevating part151. The control unit100can also change a horizontal position of the arm body by transmitting a control signal to the driving apparatus1521of the extendable arm152.

The control unit100may control the movement of the base part11by performing well-known control such as feedback control and robust control based on information about the rotations of the driving wheels13detected by a rotation sensor(s) provided in the driving wheels13. Further, the control unit100may control the operations of the carriage part130, the elevating part151, and the extendable arm152based on information such as information about a distance(s) detected by a distance sensor such as a camera or an ultrasonic sensor provided in the base part11and information about a map of the moving environment. The control unit100determines, based on the position of an obstacle detected by the camera and the position of a storage shelf, a stop position of the delivery robot and a stop direction of the delivery robot (i.e., a direction which the delivery robot is facing when it stops) relative to the storage shelf.

The control unit100includes, for example, a microcomputer including a control program executed by a Central Processing Unit (CPU)101that performs control processing, arithmetic processing, etc., a memory102including a Read Only Memory (ROM) that stores arithmetic programs etc., and an interface unit (I/F)103that inputs and outputs signals to and from the outside. The CPU101, the memory102, and the interface unit103are connected to one another through a data bus or the like.

FIG.3is a perspective view for explaining a stop position of a delivery robot relative to an obstacle.

InFIGS.1and3, an obstacle40is placed in a predetermined area near the storage shelf30, for example, at the front left side of the storage shelf. The control unit100of the delivery robot10detects a position of the obstacle40and a position of the storage shelf30by the sensor18. The control unit100determines a stop position and a stop direction of the delivery robot relative to the storage shelf as shown inFIG.3based on the detected position of the obstacle and the detected position of the storage shelf. Specifically, as shown inFIG.3, the delivery robot10stops in front of the storage shelf30so that the storage part12of the delivery robot10is positioned so as to be located on the side thereof opposite to the side thereof near the obstacle40(the side thereof far from the obstacle) and the left side of the delivery robot10faces the storage shelf30. Further, the delivery robot10can stop as close as possible to the storage shelf30so that a length that the extendable arm is extended is reduced as much as possible. Then, the control unit100of the delivery robot10controls the extendable arm152and the elevating part151based on the position of the storage shelf30transmitted by the sensor18. As a result, the mounting table15can store the article20in the intended shelf of the storage shelf30.

FIG.4is a perspective view for explaining a stop position of the delivery robot relative to an obstacle.

InFIG.4, the obstacle40is placed in a predetermined area near the storage shelf30, for example, at the front right side of the storage shelf. The control unit100of the delivery robot10detects a position of the obstacle40and a position of the storage shelf30by the sensor18, and the control unit100determines a stop position and a stop direction of the delivery robot relative to the storage shelf as shown inFIG.4based on the detected position of the obstacle and the detected position of the storage shelf. Specifically, as shown inFIG.4, the delivery robot10stops in front of the storage shelf30so that the storage part12of the delivery robot10is positioned so as to be located on the side thereof opposite to the side thereof near the obstacle40(the side thereof far from the obstacle) and the right side of the delivery robot10faces the storage shelf30. Further, the delivery robot10can stop as close as possible to the storage shelf30so that a length that the extendable arm is extended is reduced as much as possible. Then, the control unit100of the delivery robot10controls the extendable arm152and the elevating part151based on the position of the storage shelf30transmitted by the sensor18. As a result, the mounting table15can store the article20in the intended shelf of the storage shelf30.

FIG.5is a perspective view for explaining a stop position of the delivery robot relative to an obstacle.

InFIG.5, two obstacles40are respectively placed at the front left side and the front right side of the storage shelf30. The control unit100of the delivery robot10detects a position of each of the two obstacles40and a position of the storage shelf30by the sensor18, and the control unit100determines a stop position and a stop direction of the delivery robot relative to the storage shelf as shown inFIG.5based on the detected positions of the obstacles and the detected position of the storage shelf. Specifically, as shown inFIG.5, the delivery robot stops in front of the storage shelf30between the two obstacles40so that the storage part12is positioned so as to be located far from the storage shelf30and the front side of the delivery robot10faces the storage shelf30. Further, the delivery robot10can stop as close as possible to the storage shelf30so that a length that the extendable arm is extended is reduced as much as possible. Then, the control unit100of the delivery robot10controls the extendable arm152and the elevating part151based on the position of the storage shelf30transmitted by the sensor18. As a result, the mounting table15can store the article20in the intended shelf of the storage shelf30. However, since there is a risk that the passage in front of the storage shelf might be blocked when the delivery robot stops in front of the storage shelf so that the front side of the delivery robot faces the storage shelf as shown inFIG.5, the control unit preferentially selects to stop the delivery robot in front of the storage shelf so that the left side of the delivery robot faces the storage shelf as shown inFIG.3or the right side of the delivery robot faces the storage shelf as shown inFIG.4.

FIG.6is a perspective view for explaining a position of an obstacle relative to a storage shelf where the delivery robot can deliver an article to the storage shelf.

As shown inFIG.6, two storage shelves30are arranged side by side next to a wall50of a building or the like. The obstacle40is disposed so that it protrudes forward from the inside of the right storage shelf30. Therefore, the delivery robot10cannot stop in a substantially parallel manner in front of the left storage shelf30so that the left side of the delivery robot faces the storage shelf as shown inFIG.3or the right side of the delivery robot faces the storage shelf as shown inFIG.4. Further, another obstacle40is disposed slightly in front of the left storage shelf30. Therefore, the delivery robot10cannot stop in a substantially parallel manner in front of the left storage shelf30so that the front side of the delivery robot10faces the storage shelf30as shown inFIG.5. However, the control unit100of the delivery robot10may detect the positions of the two obstacles, the position of the wall50, and the positions of the two storage shelves30from the captured image, and may determine that it is possible to deliver an article by stopping the delivery robot10so that it is positioned diagonally in front of the left storage shelf30as shown inFIG.7(seeFIG.7).

FIG.7is a top view for explaining a position of the delivery robot relative to an obstacle where the delivery robot can deliver an article to the storage shelf.

The delivery robot10can stop so that the base part11faces the left storage shelf30and the delivery robot10is positioned diagonally to the front surface of the left storage shelf30while avoiding the two obstacles40. Further, the delivery robot10makes the mounting table15, which is configured so that it can be rotated about the vertical axis, face the storage shelf30, or the delivery robot10makes the mounting table15face the storage shelf30and moves it in the horizontal direction, whereby the delivery robot10can store an article in the storage shelf.

In some embodiments, when a wide storage shelf formed by integrating two storage shelves with each other such as those shown inFIG.6has a plurality of possible storage spaces (e.g., a right storage shelf30R and a left storage shelf30L), the control unit100can determine a position corresponding to the storage space where no obstacle is present (inFIG.6, the left storage shelf30L) as a stop position of the delivery robot.

In another embodiment, when a storage shelf formed by integrating two storage shelves with each other such as those shown inFIG.6has a plurality of possible storage spaces (e.g., the right storage shelf30R and the left storage shelf30L), the sensor18that detects whether or not an article is stored in a storage place may be provided in each storage shelf. By this configuration, when the sensor18detects that the article is stored in a storage place where no obstacle is present (the left storage shelf30L in this example), the control unit100takes predetermined measures to move the article to a storage place where the obstacle is present (the right storage shelf30R in this example). For example, predetermined measures may include sending a request (e.g., an email, a message) to a communication terminal of a specific person (e.g., a caretaker, a resident) so that an article stored in a storage place where no obstacle is present (e.g., the left storage shelf30L) to a storage place where an obstacle is present (e.g., the right storage shelf30R). Alternatively, a manipulator (not shown) provided inside the storage shelf30moves an article to a storage place where an obstacle is present (e.g., the right storage shelf30R). For example, each of the right storage shelf30R and the left storage shelf30L includes a manipulator. The manipulator provided in the right storage shelf30R can move an article to the left storage shelf30L through a passage (not shown) in the storage shelf.

FIG.8is a perspective view for explaining a position of an obstacle relative to a storage shelf where the delivery robot cannot deliver an article to the storage shelf.

As shown inFIG.8, two obstacles40are disposed in front of the storage shelf30. The control unit100of the delivery robot10detects a position of each of the two obstacles40and a position of the storage shelf30by the sensor18of the traveling robot60or the fixed monitoring camera70connected through a wireless or a wired network. However, the control unit100may determine that the delivery robot10cannot deliver an article to the storage shelf30based on the position of each of the obstacles40and the position of the storage shelf30detected by the sensor18, the maximum length of the extendable arm of the delivery robot10(not shown inFIG.8), the size of the delivery robot and the range of movement thereof, and the like. In this case, the delivery robot stops delivering an article to the storage shelf30and moves in order to deliver another article.

By the delivery system according to the first embodiment described above, whether or not an article can be delivered to the storage shelf may be determined based on the position of the obstacle and the position of the storage shelf detected by the sensor, the maximum length of the extendable arm of the delivery robot, the size of the delivery robot and the range of movement thereof, and the like. When the delivery system determines that an article can be delivered to the storage shelf, it may determine a stop position and a stop direction of the delivery robot relative to the storage shelf.

Second Embodiment

FIG.9is a diagram for explaining an outline of a delivery system1a. The delivery system1aincludes a storage shelf30aand a delivery robot10a. The delivery robot10conveys an article and stores it in the storage shelf30. The delivery robot10atakes an article out of the storage shelf30aand conveys the article taken out. Although not shown inFIG.9, the delivery robot10amay include the storage part12as shown inFIG.1. Further, the storage shelf30aand the delivery robot10aaccording to the second embodiment include an engagement mechanism described later so that an article can be put into a storage shelf and taken out of the storage shelf safely. InFIG.9, descriptions of the same components as those in the first embodiment will be omitted as appropriate.

The storage shelf30ahouses an article not shown. Examples of the article may include a returnable box. The storage shelf30aincludes a housing311, support members312, and guide rails313. The support member312supports an article housed in the storage shelf30a.

The guide rail313engages a groove156provided in a mounting table15aof the delivery robot10a. The guide rail313extends in the vertical direction. The guide rail313may be a plate-like member provided so as to be parallel to a front surface of the storage shelf30a. The plate-like member protrudes inwardly from the housing311. The guide rails313may be provided on each of the left and right sides of the housing311, or may instead be provided on one of the left and right sides thereof.

The delivery robot10aincludes the mounting table15a, a carriage part130a, an elevating part151a, an extendable arm152a, and an engagement detection sensor155. The mounting table15ais a table on which an article can be placed and is also referred to as a top plate. The groove156extending in the vertical direction is provided on a side surface of the mounting table15a. When the mounting table15ais moved up from below by an operation of the elevating part151a, the groove156is engaged with the guide rail313of the storage shelf30a. The groove156may be provided on each of the right-side surface and the left-side surface of the mounting table15a.

The delivery robot10ais moved in the horizontal direction by the movable carriage part130a. The elevating part151ais provided on the carriage part130a. The elevating part151amoves the mounting table15aup and down. The extendable arm152aextends and contracts in the horizontal direction. The extendable arm152atakes an article out of the storage shelf30aand places the article on the mounting table15a, and stores the article on the mounting table15ain the storage shelf30.

The engagement detection sensor155is provided in the groove156. The engagement detection sensor155detects that the guide rail313is engaged with the groove156. When the guide rail313is engaged with the groove156, the guide rail313is engaged with the mounting table15a. The engagement detection sensor155is, for example, a photo interrupter or a photo reflector. In this case, the engagement detection sensor155includes a light emitting unit and a light receiving unit. When the light from the light emitting unit is blocked by the guide rail313, the engagement detection sensor155may detect that the guide rail313is engaged with the mounting table15. When the light from the light emitting unit is reflected by the guide rail313, the engagement detection sensor155may detect that the guide rail313is engaged with the mounting table15a. Note that the engagement detection sensor155may be a sensor (e.g., a contact sensor, a magnetic sensor) that detects a force received from the guide rail313.

As shown inFIG.10, the delivery robot10aincludes a control unit100aand a safety control unit157. The control unit100acontrols normal operations of the carriage part130a, the elevating part151a, and the extendable arm152a. The safety control unit157stops (e.g., urgently stops) the operation of the elevating part151abased on a result of detection by the engagement detection sensor155. The safety control unit157may also stop the operations of the carriage part130aand the extendable arm152a.

The groove156extending in the vertical direction is provided on the side surface of the mounting table15a. The groove156is provided so as to extend from the lower surface of the mounting table15ato the upper surface thereof. The groove156is engageable with the guide rail313.

The carriage part130aincludes a base part11a, a pair of right and left driving wheels13and a pair of front and rear driven wheels13rotatably disposed in the base part11a, and a pair of motors1301that rotationally drive the respective driving wheels13. Each of the motors1301rotates a respective one of the driving wheels13through a speed reducer or the like. Each of the motors1301rotates a respective one of the driving wheels13in accordance with a control signal sent from the control unit100a. Each of the motors1301rotates a respective one of the driving wheels13in accordance with a control signal sent from the control unit100a, thereby enabling the base part11ato move to any position.

The mounting table15amoves up and down by the elevating part151aextending and contracting along the vertical axis. The elevating part151amay be formed as a telescopic expanding/contracting mechanism that extends and contracts in the vertical direction. The extendable arm152ais attached to the mounting table15a. The extendable arm152aincludes an arm body and a driving apparatus1521a. The driving apparatus1521a, which is attached to a guide rail mechanism (not shown) in the mounting table15a, moves the arm body in the horizontal direction. The driving apparatus1521amay further include a mechanism that rotates the arm body around the axis.

The engagement detection sensor155is provided in the groove156. The engagement detection sensor155may be provided on each of the left and right sides of the mounting table15a. The engagement detection sensor155can detect that the groove156is engaged with the guide rail313. The delivery robot10amay further include a movement detection sensor that detects movement of the carriage part130aand a height detection sensor that detects a height of the mounting table15a.

The control unit100acontrols normal operations of the carriage part130a, the elevating part151a, and the extendable arm152a. The control unit100acan control the rotation of each of the driving wheels13and move the base part11ato any position by transmitting a control signal to each of the motors1301of the carriage part130a. The control unit100acan control a height position of the mounting table15aby transmitting a control signal to the rotating apparatus1511of the elevating part151a. The control unit100acan also control a horizontal position of the arm body by transmitting a control signal to the driving apparatus1521aof the extendable arm152a.

The control unit100amay control the movement of the base part11aby performing well-known control such as feedback control and robust control based on information about the rotations of the driving wheels13detected by a rotation sensor(s) provided in the driving wheels13. Further, the control unit100amay control the operations of the carriage part130a, the elevating part151a, and the extendable arm152abased on information such as information about a distance(s) detected by a distance sensor such as a camera or an ultrasonic sensor provided in the base part11aand information about a map of the moving environment.

The control unit100ais mainly composed of, for example, hardware such as a microcomputer including the Central Processing Unit (CPU)101that performs control processing, arithmetic processing, and the like, the memory102including Read Only Memory (ROM) that stores a control program, an arithmetic program, and the like executed by the CPU101, and the interface unit (I/F)103that inputs and outputs signals from and to the outside. The CPU101, the memory102, and the interface unit103are connected to one another through a data bus or the like.

The safety control unit157acquires a result of detection by the engagement detection sensor155. The safety control unit157may further acquire a result of detection by a sensor other than the engagement detection sensor155. The safety control unit157stops the operation of the elevating part151awhen a first condition including that the guide rail313is not engaged with the mounting table15ais satisfied.

Like the control unit100a, the safety control unit157may include a processor, a memory, and the like. The safety control unit157may be a Programmable Logic Controller (PLC). The control unit100amay include the safety control unit157.

The first condition may further include that a height of the mounting table15ais greater than or equal to a predetermined height h1. When the safety control unit157stops the operation of the elevating part151a, the safety control unit157may stop the supply of power to the elevating part151a.

Note that when the guide rail313is engaged with the mounting table15a, it is not necessary to extend the elevating part151ain some cases. For example, when the mounting table15ais configured so that it can be tilted, the guide rail313can, upon the mounting table15abeing tilted, engage therewith. Further, for example, when the guide rail313is provided on one side of the storage shelf30, the guide rail313can be engaged with the mounting table15aby the delivery robot10amoving in a direction parallel to the front surface of the storage shelf30a. In such a case, the first condition may not include a condition regarding the height of the mounting table15a.

As described above, the delivery system according to the second embodiment can detect whether or not the mounting table is engaged with the storage shelf, thereby safely storing an article. Therefore, in the second embodiment, the control unit100adetermines a stop position of the delivery robot relative to the storage shelf so that the mounting table can be engaged with the storage shelf.

For example, the control unit100adetermines, based on the position of the detected obstacle, a stop position of the delivery robot relative to the storage shelf and a stop direction in which the delivery robot stops in front of the storage shelf so that either a left side or a right side of the delivery robot faces the storage shelf (seeFIGS.3and4), the stop position and the stop direction enabling the groove formed in the mounting table of the delivery robot to be engaged with the guide rail of the storage shelf.

Further, the control unit100adetermines, based on the position of the detected obstacle, a stop position of the delivery robot relative to the storage shelf and a stop direction in which the delivery robot stops in front of the storage shelf so that the front side of the delivery robot faces the storage shelf (seeFIG.5), the stop position and the stop direction enabling the groove formed in the mounting table of the delivery robot to be engaged with the guide rail of the storage shelf. However, since there is a risk that the passage of an apartment building etc. might be blocked when the delivery robot stops in front of the storage shelf so that the front side of the delivery robot faces the storage shelf, the control unit100may preferentially select to stop the delivery robot so that either the left side or the right side of the delivery robot faces the storage shelf (seeFIGS.3and4).

In another embodiment, the control unit100may determine, based on the detected position of the obstacle, a stop position of the delivery robot relative to the storage shelf and a stop direction relative to the storage shelf in which the groove formed in the mounting table of the delivery robot cannot be engaged with the guide rail of the storage shelf and an article can be stored in the storage shelf. As described above, since the mounting table15aof the delivery robot is configured to be rotatable 360 degrees, the delivery robot may stop so that it is positioned diagonally in front of the storage shelf and store an article in the storage shelf by means of the extendable arm or the like. In this case, the extendable arm is extended longer than in the case where the groove can be engaged with the guide rail.

Although the delivery system has been described in the above embodiments, the present disclosure is also applicable to a delivery method using the components of the delivery system.

The above-described program includes instructions (or software codes) that, when loaded into a computer, cause the computer to perform one or more of the functions described in the example embodiments. The program may be stored in a non-transitory computer readable medium or a tangible storage medium. By way of example, and not a limitation, non-transitory computer readable media or tangible storage media can include a random-access memory (RAM), a read-only memory (ROM), a flash memory, a solid-state drive (SSD) or other types of memory technologies, a CD-ROM, a digital versatile disc (DVD), a Blu-ray (Registered Trademark) disc or other types of optical disc storage, a magnetic cassette, a magnetic tape, and a magnetic disk storage or other types of magnetic storage devices. The program may be transmitted on a transitory computer readable medium or a communication medium. By way of example, and not a limitation, transitory computer readable media or communication media can include electrical, optical, acoustical, or other forms of propagated signals.

Note that the present disclosure is not limited to the above-described embodiments and may be changed as appropriate without departing from the scope and spirit of the present disclosure. A plurality of examples described above can also be executed by combining them with one another as appropriate.