FIG. 5 based on the detected positions of the obstacles and the detected position of the storage shelf. Specifically, as shown in FIG. 5, the delivery robot stops in front of the storage shelf 30 between the two obstacles 40 so that the storage part 12 is positioned so as to be located far from the storage shelf 30 and the front side of the delivery robot 10 faces the storage shelf 30. Further, the delivery robot 10 can stop as close as possible to the storage shelf 30 so that a length that the extendable arm is extended is reduced as much as possible. Then, the control unit 100 of the delivery robot 10 controls the extendable arm 152 and the elevating part 151 based on the position of the storage shelf 30 transmitted by the sensor 18. As a result, the mounting table 15 can store the article 20 in the intended shelf of the storage shelf 30. 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 in FIG. 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 in FIG. 3 or the right side of the delivery robot faces the storage shelf as shown in FIG. 4.

FIG. 6 is 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 in FIG. 6, two storage shelves 30 are arranged side by side next to a wall 50 of a building or the like. The obstacle 40 is disposed so that it protrudes forward from the inside of the right storage shelf 30. Therefore, the delivery robot 10 cannot stop in a substantially parallel manner in front of the left storage shelf 30 so that the left side of the delivery robot faces the storage shelf as shown in FIG. 3 or the right side of the delivery robot faces the storage shelf as shown in FIG. 4. Further, another obstacle 40 is disposed slightly in front of the left storage shelf 30. Therefore, the delivery robot 10 cannot stop in a substantially parallel manner in front of the left storage shelf 30 so that the front side of the delivery robot 10 faces the storage shelf 30 as shown in FIG. 5. However, the control unit 100 of the delivery robot 10 may detect the positions of the two obstacles, the position of the wall 50, and the positions of the two storage shelves 30 from the captured image, and may determine that it is possible to deliver an article by stopping the delivery robot 10 so that it is positioned diagonally in front of the left storage shelf 30 as shown in FIG. 7 (see FIG. 7).

FIG. 7 is 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 robot 10 can stop so that the base part 11 faces the left storage shelf 30 and the delivery robot 10 is positioned diagonally to the front surface of the left storage shelf 30 while avoiding the two obstacles 40. Further, the delivery robot 10 makes the mounting table 15, which is configured so that it can be rotated about the vertical axis, face the storage shelf 30, or the delivery robot 10 makes the mounting table 15 face the storage shelf 30 and moves it in the horizontal direction, whereby the delivery robot 10 can 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 in FIG. 6 has a plurality of possible storage spaces (e.g., a right storage shelf 30R and a left storage shelf 30L), the control unit 100 can determine a position corresponding to the storage space where no obstacle is present (in FIG. 6, the left storage shelf 30L) 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 in FIG. 6 has a plurality of possible storage spaces (e.g., the right storage shelf 30R and the left storage shelf 30L), the sensor 18 that detects whether or not an article is stored in a storage place may be provided in each storage shelf. By this configuration, when the sensor 18 detects that the article is stored in a storage place where no obstacle is present (the left storage shelf 30L in this example), the control unit 100 takes predetermined measures to move the article to a storage place where the obstacle is present (the right storage shelf 30R 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 shelf 30L) to a storage place where an obstacle is present (e.g., the right storage shelf 30R). Alternatively, a manipulator (not shown) provided inside the storage shelf 30 moves an article to a storage place where an obstacle is present (e.g., the right storage shelf 30R). For example, each of the right storage shelf 30R and the left storage shelf 30L includes a manipulator. The manipulator provided in the right storage shelf 30R can move an article to the left storage shelf 30L through a passage (not shown) in the storage shelf.

FIG. 8 is 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 in FIG. 8, two obstacles 40 are disposed in front of the storage shelf 30. The control unit 100 of the delivery robot 10 detects a position of each of the two obstacles 40 and a position of the storage shelf 30 by the sensor 18 of the traveling robot 60 or the fixed monitoring camera 70 connected through a wireless or a wired network. However, the control unit 100 may determine that the delivery robot 10 cannot deliver an article to the storage shelf 30 based on the position of each of the obstacles 40 and the position of the storage shelf 30 detected by the sensor 18, the maximum length of the extendable arm of the delivery robot 10 (not shown in FIG. 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 shelf 30 and 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. 9 is a diagram for explaining an outline of a delivery system 1a. The delivery system 1a includes a storage shelf 30a and a delivery robot 10a. The delivery robot 10 conveys an article and stores it in the storage shelf 30. The delivery robot 10a takes an article out of the storage shelf 30a and conveys the article taken out. Although not shown in FIG. 9, the delivery robot 10a may include the storage part 12 as shown in FIG. 1. Further, the storage shelf 30a and the delivery robot 10a according 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. In FIG. 9, descriptions of the same components as those in the first embodiment will be omitted as appropriate.

The storage shelf 30a houses an article not shown. Examples of the article may include a returnable box. The storage shelf 30a includes a housing 311, support members 312, and guide rails 313. The support member 312 supports an article housed in the storage shelf 30a.

The guide rail 313 engages a groove 156 provided in a mounting table 15a of the delivery robot 10a. The guide rail 313 extends in the vertical direction. The guide rail 313 may be a plate-like member provided so as to be parallel to a front surface of the storage shelf 30a. The plate-like member protrudes inwardly from the housing 311. The guide rails 313 may be provided on each of the left and right sides of the housing 311, or may instead be provided on one of the left and right sides thereof.

The delivery robot 10a includes the mounting table 15a, a carriage part 130a, an elevating part 151a, an extendable arm 152a, and an engagement detection sensor 155. The mounting table 15a is a table on which an article can be placed and is also referred to as a top plate. The groove 156 extending in the vertical direction is provided on a side surface of the mounting table 15a. When the mounting table 15a is moved up from below by an operation of the elevating part 151a, the groove 156 is engaged with the guide rail 313 of the storage shelf 30a. The groove 156 may be provided on each of the right-side surface and the left-side surface of the mounting table 15a.

The delivery robot 10a is moved in the horizontal direction by the movable carriage part 130a. The elevating part 151a is provided on the carriage part 130a. The elevating part 151a moves the mounting table 15a up and down. The extendable arm 152a extends and contracts in the horizontal direction. The extendable arm 152a takes an article out of the storage shelf 30a and places the article on the mounting table 15a, and stores the article on the mounting table 15a in the storage shelf 30.

The engagement detection sensor 155 is provided in the groove 156. The engagement detection sensor 155 detects that the guide rail 313 is engaged with the groove 156. When the guide rail 313 is engaged with the groove 156, the guide rail 313 is engaged with the mounting table 15a. The engagement detection sensor 155 is, for example, a photo interrupter or a photo reflector. In this case, the engagement detection sensor 155 includes a light emitting unit and a light receiving unit. When the light from the light emitting unit is blocked by the guide rail 313, the engagement detection sensor 155 may detect that the guide rail 313 is engaged with the mounting table 15. When the light from the light emitting unit is reflected by the guide rail 313, the engagement detection sensor 155 may detect that the guide rail 313 is engaged with the mounting table 15a. Note that the engagement detection sensor 155 may be a sensor (e.g., a contact sensor, a magnetic sensor) that detects a force received from the guide rail 313.

As shown in FIG. 10, the delivery robot 10a includes a control unit 100a and a safety control unit 157. The control unit 100a controls normal operations of the carriage part 130a, the elevating part 151a, and the extendable arm 152a. The safety control unit 157 stops (e.g., urgently stops) the operation of the elevating part 151a based on a result of detection by the engagement detection sensor 155. The safety control unit 157 may also stop the operations of the carriage part 130a and the extendable arm 152a.

The groove 156 extending in the vertical direction is provided on the side surface of the mounting table 15a. The groove 156 is provided so as to extend from the lower surface of the mounting table 15a to the upper surface thereof. The groove 156 is engageable with the guide rail 313.

The carriage part 130a includes a base part 11a, a pair of right and left driving wheels 13 and a pair of front and rear driven wheels 13 rotatably disposed in the base part 11a, and a pair of motors 1301 that rotationally drive the respective driving wheels 13. Each of the motors 1301 rotates a respective one of the driving wheels 13 through a speed reducer or the like. Each of the motors 1301 rotates a respective one of the driving wheels 13 in accordance with a control signal sent from the control unit 100a. Each of the motors 1301 rotates a respective one of the driving wheels 13 in accordance with a control signal sent from the control unit 100a, thereby enabling the base part 11a to move to any position.

The mounting table 15a moves up and down by the elevating part 151a extending and contracting along the vertical axis. The elevating part 151a may be formed as a telescopic expanding/contracting mechanism that extends and contracts in the vertical direction. The extendable arm 152a is attached to the mounting table 15a. The extendable arm 152a includes an arm body and a driving apparatus 1521a. The driving apparatus 1521a, which is attached to a guide rail mechanism (not shown) in the mounting table 15a, moves the arm body in the horizontal direction. The driving apparatus 1521a may further include a mechanism that rotates the arm body around the axis.

The engagement detection sensor 155 is provided in the groove 156. The engagement detection sensor 155 may be provided on each of the left and right sides of the mounting table 15a. The engagement detection sensor 155 can detect that the groove 156 is engaged with the guide rail 313. The delivery robot