Patent Publication Number: US-2022227576-A1

Title: Trash box

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority to Japanese Patent Application No. 
     2021-008015 filed on Jan. 21, 2021, incorporated herein by reference in its entirety. 
     BACKGROUND 
     1. Technical Field 
     This disclosure relates to a trash box. 
     2. Description of Related Art 
     Generally, trash is temporarily accumulated in a trash box, and after that, the trash is collected from the trash box and carried to a trash collection site or the like. Japanese Unexamined Patent Application Publication No. 2009-096636 (JP 2009-096636 A) discloses a trash box including a freely openable and closable base plate provided on a bottom surface of the trash box. The trash box is fixed to a wall distanced from a floor face. 
     SUMMARY 
     With the use of a trash box described in JP 2009-096636 A, the trash accumulated inside the trash box can be collected from the bottom surface of the trash box. However, since the trash box is fixed to the wall at a distance from the floor face, an input port via which trash is put into the trash box is placed at a high position, so that it is difficult for short people such as children to put trash into the trash box. 
     This disclosure is accomplished in view of the above circumstances, and an object of this disclosure is to provide a trash box that can maintain a balance between collection of trash from the lower side of a trash box and convenience for a user who puts trash into the trash box. 
     One aspect to achieve the above object is a trash box is a trash box including a trash box main body in which trash is accommodate. A top surface or a side surface of the trash box main body includes an input port via which the trash is put into the trash box main body. A bottom surface of the trash box main body includes an opening-closing portion. The trash box main body is placed such that the opening-closing portion faces a reference plane that is a floor face or ground. The trash box main body is changeable in height from the reference plane. The trash box configured as such can achieve a height of the trash box main body, the height being suitable to collect trash from the lower side of the trash box, and a height of the trash box main body, the height being suitable for a person to put trash into the trash box. This makes it possible to balance collection of trash from the lower side of the trash box with convenience for a user who puts trash into the trash box. 
     In the one aspect, the trash box main body may be changeable between a first state where the trash box main body is distanced from the reference plane at a predetermined distance and a second state where a distance between the trash box main body and the reference plane is shorter than the predetermined distance. The predetermined distance may be larger than a height of an autonomous mobile robot configured to collect trash falling from the trash box main body when the opening-closing portion is opened. 
     With such a configuration, it is possible to solve a problem that the input port is placed too high for a user to put trash into the trash box, and it is also possible to achieve collection of the trash by the autonomous mobile robot. 
     In the one aspect, the trash box may include a driving device configured to change a height of the trash box main body. With such a configuration, the height of the trash box main body is automatically changeable, thereby making it possible to improve the convenience of the trash box. 
     In the one aspect, when a state where the autonomous mobile robot comes near an installation position of the trash box main body is detected, the driving device may change a state of the trash box main body to the first state. With such a configuration, in a case where the autonomous mobile robot arrives, the height of the trash box main body can be changed automatically so that the autonomous mobile robot can move under the trash box main body. 
     In the one aspect, when a state where a person comes near the installation position of the trash box main body is detected, the driving device may change the state of the trash box main body to the second state. With such a configuration, in a case where a person arrives, the height of the trash box main body can be changed automatically to a height suitable for the person to put trash into the trash box. 
     In the one aspect, when a state where a person shorter than a predetermined threshold comes near the installation position of the trash box main body is detected, the driving device may change the state of the trash box main body to the second state. With such a configuration, in a case where a person who does not require a height change in the trash box main body, it is possible to restrain the trash box main body from being unnecessarily changed in height. 
     In the one aspect, the driving device may change the height of the trash box main body in response to a recognition result of a gesture or a voice of a person. With such a configuration, it is possible to improve the convenience of the trash box. 
     In the one aspect, the driving device may change the height of the trash box main body in response to an operation on an operating portion provided in the trash box. With such a configuration, it is possible to improve the convenience of the trash box. 
     With this disclosure, it is possible to provide a trash box that can maintain a balance between collection of trash from the lower side of the trash box and convenience for a user who puts trash into the trash box. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Features, advantages, and technical and industrial significance of exemplary embodiments of the disclosure will be described below with reference to the accompanying drawings, in which like signs denote like elements, and wherein: 
         FIG. 1  is a schematic view illustrating one exemplary configuration of a trash collection system according to an embodiment; 
         FIG. 2  is a schematic view illustrating a state where a trash box main body is lowered; 
         FIG. 3  is a block diagram illustrating constituents of a trash box of the embodiment, the constituents being related to a height control of the trash box main body and discharge of trash; 
         FIG. 4  is a schematic view illustrating a state where an opening-closing portion is opened; 
         FIG. 5  is a perspective view illustrating a schematic configuration of an autonomous mobile robot according to the embodiment; 
         FIG. 6  is a side view illustrating a schematic configuration of the autonomous mobile robot according to the embodiment; 
         FIG. 7  is a block diagram illustrating a schematic system configuration of the autonomous mobile robot according to the embodiment; and 
         FIG. 8  is a flowchart illustrating an example of an operation of the trash box according to the embodiment. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     With reference to drawings, the following describes an embodiment of the present disclosure. 
       FIG. 1  is a schematic view illustrating one exemplary configuration of a trash collection system  1  according to an embodiment. As illustrated in  FIG. 1 , the trash collection system  1  includes a trash box  2  and an autonomous mobile robot  10 . Note that, in  FIG. 1 , a collection box  30  placed on a placement portion  130  provided in an upper part of the autonomous mobile robot  10  is also illustrated. The trash box  2  is provided in a given environment such as a house, a facility, a storeroom, a factory, the outdoors, and so on, for example. 
     The trash box  2  includes a trash box main body  20  and a sliding mechanism  25 . The trash box main body  20  is a container in which trash  31  is accommodated. In  FIG. 1 , a section of the trash box main body  20  is illustrated. The trash box main body  20  has, for example, a cuboid shape, a columnar shape, or the like, but these are just examples. The trash box main body  20  may have other shapes. 
     The trash box main body  20  illustrated in  FIG. 1  has an input port  21  and a discharge port  22 . The input port  21  is an opening via which people or the like put trash  31  into the trash box main body  20 . In the example illustrated in  FIG. 1 , the input port  21  is provided on a top surface of the trash box main body  20 , but the input port  21  may be provided on a side surface of the trash box main body  20 . 
     The discharge port  22  is an opening via which the autonomous mobile robot  10  collects the trash  31  inside the trash box main body  20 . An opening-closing portion  23  is provided in the discharge port  22 . The opening-closing portion  23  is a door (cover) provided in the discharge port  22  and can change the state of the discharge port  22  between a closed state (see  FIG. 1 ) and an opened state (see  FIG. 4 ). In the example illustrated in  FIG. 1 , the opening-closing portion  23  is a single swing door. However, the opening-closing portion  23  may be a double door or may be configured to open and close the discharge port  22  by three or more doors. Further, the opening-closing portion  23  is not limited to a configuration in which the discharge port  22  is opened and closed by rotating a door. The opening-closing portion  23  may be configured to open and close the discharge port  22  by sliding a door. That is, the opening-closing portion  23  should be any component configured to change the state of the discharge port  22  between the closed state and the opened state, and the opening-closing portion  23  can employ a well-known given configuration as its specific configuration. Note that, in the example illustrated in  FIG. 1 , the input port  21  is not provided with an opening-closing portion, but the input port  21  may be also provided with an opening-closing portion. 
     The discharge port  22  and the opening-closing portion  23  are provided on a predetermined surface of the trash box main body  20 , more specifically, a bottom surface of the trash box main body  20 . As illustrated in  FIG. 1 , the trash box main body  20  is provided by use of a sliding mechanism  25  such that the opening-closing portion  23  and the discharge port  22  face a reference plane  32  that is a floor face or ground, that is, the predetermined surface on which the opening-closing portion  23  is provided faces the reference plane  32 . The trash box main body  20  is attached to the sliding mechanism  25 . As illustrated in  FIG. 1 , for example, the sliding mechanism  25  includes a support  251 , a slider  252 , and a slider driving device  253 . The support  251  is a support configured to support the trash box main body  20 . The support  251  supports the trash box main body  20  such that the height of the trash box main body  20  is changeable. More specifically, the height of the trash box main body  20  is changed by the slider  252  and the slider driving device  253  provided in the support  251 . The slider  252  is a component linearly moving in the up-down direction in the support  251  and is attached to the trash box main body  20 . Accordingly, the trash box main body  20  moves in the up-down direction along with the movement of the slider  252 , so that the installation height of the trash box main body  20  changes. The position of the slider  252  is changed by the slider driving device  253 . The slider driving device  253  includes an actuator such as a motor, and a controller configured to control the actuator. Note that the controller may have a function as a computer. That is, the controller may include a processor and a memory. 
       FIG. 1  is a schematic view illustrating a state where the trash box main body  20  is raised. In the meantime,  FIG. 2  is a schematic view illustrating a state where the trash box main body  20  is lowered. As illustrated in  FIG. 1 , in a case where the trash box main body  20  is raised, a space into which the autonomous mobile robot  10  enters is formed below the trash box main body  20 . Accordingly, when the opening-closing portion  23  is opened, the autonomous mobile robot  10  can receive the trash  31  falling from the trash box main body  20 . However, in this case, the trash box main body  20  is raised, and therefore, it might be difficult for people to reach the input port  21 . Particularly, it is difficult for a short user to reach the input port  21 . Accordingly, it might be difficult for the short user to put trash into the trash box main body  20 . In the meantime, as illustrated in  FIG. 2 , in a case where the trash box main body  20  is lowered, the input port  21  is also lowered, so that a user  90  can easily put trash into the trash box main body  20 . Note that, in the example illustrated in  FIG. 2 , the trash box main body  20  floats from the reference plane  32 , but the trash box main body  20  may be lowered to the height at which the trash box main body  20  makes contact with the reference plane  32 . 
     As such, the trash box main body  20  can be changed between a first state (hereinafter referred to as a raised state) where the trash box main body  20  is distanced from the reference plane  32  at a predetermined distance and a second state (hereinafter referred to as a lowered state) where the distance between the trash box main body  20  and the reference plane  32  is shorter than the predetermined distance. Here, the predetermined distance is larger than the height of the autonomous mobile robot  10  configured to collect the trash  31  falling from the trash box main body  20  when the opening-closing portion  23  is opened. This configuration can solve the problem that the input port is placed too high for a user to put trash into the trash box, as described above, and can achieve collection of the trash  31  by the autonomous mobile robot  10 . 
       FIG. 3  is a block diagram illustrating constituents of the trash box  2  of the present embodiment, the constituents being related to a height control of the trash box main body  20  and discharge of trash. As illustrated in  FIG. 3 , the trash box  2  includes a sensor  24  in addition to the opening-closing portion  23  and the sliding mechanism  25 . The sensor  24  may be provided in the trash box main body  20  or may be provided in the support  251 . 
     The sensor  24  is a sensor configured to recognize approach of an object and the object thus approaching the trash box  2 . The sensor  24  particularly detects whether the object thus approaching the trash box  2  is a person or the autonomous mobile robot  10 . Further, the sensor  24  also detects whether the object has arrived at a predetermined position or not. Here, the predetermined position is, specifically, a collecting position at which the trash  31  accommodated in the trash box main body  20  is collected, and more specifically, a position right under the opening-closing portion  23 . The sensor  24  may be a camera and an image processor configured to process an image captured by the camera, for example, or may be a well-known sensor. 
     In the present embodiment, the slider driving device  253  of the sliding mechanism  25  changes the position of the slider  252 , that is, the position of the trash box main body  20  in the up-down direction, based on a detection result from the sensor  24 . That is, the slider driving device  253  changes the height of the trash box main body  20 . More specifically, when the sensor  24  detects the autonomous mobile robot  10  coming near the installation position of the trash box main body  20  (e.g., within a predetermined range from the installation position of the trash box main body  20 ), the slider driving device  253  changes the state of the trash box main body  20  to the raised state. Hereby, in a case where the autonomous mobile robot  10  arrives, the height of the trash box main body  20  can be changed automatically so that the autonomous mobile robot  10  moves under the trash box main body  20 . Further, when the sensor  24  detects a person coming near the installation position of the trash box main body  20 , the slider driving device  253  changes the state of the trash box main body  20  to the lowered state. Hereby, in a case where a person arrives, the height of the trash box main body  20  can be changed automatically to a height suitable for the person to put trash into the trash box main body  20 . Note that, only when the sensor  24  detects a person coming near the installation position of the trash box main body  20 , the person being shorter than a predetermined threshold, the slider driving device  253  may change the state of the trash box main body  20  to the lowered state. This configuration can restrain the height of the trash box main body  20  from being changed unnecessarily in a case where a person who does not require a height change in the trash box main body  20 . 
     Further, the opening-closing portion  23  of the present embodiment is changed from the closed state to the opened state based on the detection result from the sensor  24 . That is, when the sensor  24  detects the autonomous mobile robot  10  arriving at a predetermined position (the collecting position to collect the trash  31 ), the opening-closing portion  23  opens the door that has closed the discharge port  22 , so that the discharge port  22  is opened. The opening-closing portion  23  may include an actuator such as a motor, for example, and may be changed between the opened state and the closed state by the actuator. Note that, when a predetermined time passes after the opening-closing portion  23  is brought into the opened state, the opening-closing portion  23  may shift to the closed state. Further, when the sensor  24  detects the autonomous mobile robot  10  leaving from the predetermined position, the opening-closing portion  23  may shift to the closed state. Note that the opening-closing portion  23  may not include an electrical drive mechanism for the operation of the door. For example, the opening-closing portion  23  may be opened by the deadweight of the door of the opening-closing portion  23 , elastic force of an elastic member, or the like. In this case, for example, when a fastener configured to prevent opening of the door of the opening-closing portion  23  operates in response to a detection result, the opening-closing portion  23  may be opened by the deadweight, the elastic force, or the like. Further, in terms of closing of the opening-closing portion  23 , the opening-closing portion  23  may be closed by a person or a robot instead of automatic door closing of the trash box  2 . 
       FIG. 4  is a schematic view illustrating a state where the opening-closing portion  23  is opened. As illustrated in  FIG. 4 , in the present embodiment, when the autonomous mobile robot  10  arrives at the predetermined position, the sensor  24  detects this, and the opening-closing portion  23  is opened. Hereby, the trash  31  accommodated in the trash box main body  20  falls down, so that the trash  31  is put on the placement portion  130  of the autonomous mobile robot  10 . Note that, in  FIG. 4 , the collection box  30  in which the collected trash  31  is put is placed on the autonomous mobile robot  10 , but the trash  31  may be directly placed on the autonomous mobile robot  10  without using the collection box  30 . 
     Next will be described the autonomous mobile robot  10 .  FIG. 5  is a perspective view illustrating a schematic configuration of the autonomous mobile robot  10  according to the present embodiment.  FIG. 6  is a side view illustrating a schematic configuration of the autonomous mobile robot  10  according to the present embodiment.  FIG. 7  is a block diagram illustrating a schematic system configuration of the autonomous mobile robot  10  according to the present embodiment. 
     The autonomous mobile robot  10  according to the present embodiment is a robot configured to autonomously move in a movement environment such as a house, a facility, a storeroom, a factory, or the indoors, for example. The autonomous mobile robot  10  collects the trash  31  in the trash box  2  and carries the trash  31  to a predetermined place. The autonomous mobile robot  10  travels on the reference plane  32 , for example. The autonomous mobile robot  10  according to the present embodiment includes a movable moving portion  110 , an expansion-contraction portion  120  configured to expand and contract in the up-down direction, the placement portion  130  configured to support an object (the trash  31 ) placed thereon, a controlling portion  100  configured to control the autonomous mobile robot  10 , including controls of the moving portion  110  and the expansion-contraction portion  120 , and a wireless communication portion  140 . 
     The moving portion  110  includes a robot main body  111 , a pair of right and left driving wheels  112  and a pair of front and rear driven wheels  113  rotatably provided in the robot main body  111 , and a pair of motors  114  configured to rotationally drive the driving wheels  112 . The motors  114  rotates the driving wheels  112 , respectively, via respective speed reducers or the like. When the motors  114  rotate the driving wheels  112  in response to a control signal from the controlling portion  100 , the robot main body  111  is allowed to move forward, move rearward, and rotate. Hereby, the robot main body  111  can move to a given position. Note that the configuration of the moving portion  110  is just one example, and the moving portion  110  is not limited to this. For example, any numbers of the driving wheels  112  and the driven wheels  113  in the moving portion  110  can be provided, and the moving portion  110  can employ any configuration, provided that the moving portion  110  can move the robot main body  111  to a given position. 
     The expansion-contraction portion  120  is an expansion-contraction mechanism configured to expand and contract in the up-down direction. The expansion-contraction portion  120  may be configured as a telescopic expansion-contraction mechanism. The placement portion  130  is provided in an upper end part of the expansion-contraction portion  120 , and the placement portion  130  is raised and lowered by operation of the expansion-contraction portion  120 . The expansion-contraction portion  120  includes a driving device  121  such as a motor, and the expansion-contraction portion  120  is driven by the driving device  121  so as to expand and contract. That is, the placement portion  130  is raised and lowered by the driving of the driving device  121 . The driving device  121  drives the expansion-contraction portion  120  in response to a control signal from the controlling portion  100 . Note that, instead of the expansion-contraction portion  120 , the autonomous mobile robot  10  may employ a well-known given mechanism configured to control the height of the placement portion  130  provided on the upper side of the robot main body  111 . 
     The placement portion  130  is provided in an upper part (a distal end) of the expansion-contraction portion  120 . The placement portion  130  is raised and lowered by the driving device  121  such as a motor and is used to place the trash  31  carried by the autonomous mobile robot  10  on the placement portion  130 . Note that, as illustrated in  FIG. 1 , the collection box  30  in which the collected trash  31  is put may be placed on the placement portion  130 . However, as described above, the trash  31  may be directly placed on the placement portion  130  without using the collection box  30 . In order to carry the trash  31 , the autonomous mobile robot  10  moves together with the trash  31  (the collection box  30 ) with the trash  31  (the collection box  30 ) being supported by the placement portion  130 . Hereby, the autonomous mobile robot  10  carries the trash  31  (the collection box  30 ). 
     The placement portion  130  is made of a plate material, for example. In the present embodiment, the shape of the plate material, that is, the shape of the placement portion  130 , is a discoid shape with a flat top surface, for example, but may be any other shapes. 
     The wireless communication portion  140  is a circuit configured to perform wireless communication so as to communicate with a server, other robots, and so on as needed. For example, the wireless communication portion  140  includes a wireless transmission-reception circuit and an antenna. In a case where the trash box  2  has a communication function, the autonomous mobile robot  10  may communicate with the trash box  2  by the wireless communication portion  140 . Note that the wireless communication portion  140  may be omitted in a case where the autonomous mobile robot  10  does not communicate with other devices. 
     The controlling portion  100  is a device configured to control the autonomous mobile robot  10  and includes a processor  101 , a memory  102 , and an interface  103 . The processor  101 , the memory  102 , and the interface  103  are connected to each other via data buses and the like. 
     The interface  103  is an input-output circuit to be used to communicate with other devices such as the moving portion  110 , the expansion-contraction portion  120 , and the wireless communication portion  140 . 
     The memory  102  is constituted by a volatile semiconductor memory and a nonvolatile semiconductor memory in combination, for example. The memory  102  is used to store software (computer programs) including one or more orders and executed by the processor  101 , data to be used for various processes of the autonomous mobile robot  10 , and so on. 
     The processor  101  performs a process (described later) of the controlling portion  100  by reading out the software (the computer programs) from the memory  102  and executing the software (the computer programs). 
     The processor  101  may be, for example, a microprocessor, a microprocessor unit (MPU), a central processing unit (CPU), or the like. The processor  101  may include a plurality of processors. Thus, the controlling portion  100  is a device functioning as a computer. 
     Note that the programs can be stored by use of various types of non-transitory computer readable media and supplied to the computer. The non-transitory computer readable media include various types of tangible storage media. Examples of the non-transitory computer readable media include magnetic recording media (e.g., a flexible disk, a magnetic tape, a hard disk drive), optical magnetic recording media (e.g., a magneto-optical disk), a CD read-only memory (CD-ROM), a CD-R, a CD-R/W, and a semiconductor memory (e.g., a mask ROM, a programmable ROM (PROM), an erasable PROM (EPROM), a flash ROM, and a random access memory (RAM)). Further, the programs can be supplied to the computer by various types of transitory computer readable media. Examples of the transitory computer readable media include an electrical signal, an optical signal, and an electromagnetic wave. The transitory computer readable media can supply the programs to the computer via a wired communication channel such as an electric wire or an optical fiber, or a wireless communication channel. 
     Next will be described the process of the controlling portion  100 . The controlling portion  100  controls the operation of the autonomous mobile robot  10 . For example, the controlling portion  100  controls the moving portion  110  and the expansion-contraction portion  120 . The controlling portion  100  controls the rotation of the driving wheels  112  by transmitting control signals to the motors  114  of the moving portion  110 , and hereby, the controlling portion  100  can move the robot main body  111  to a given position. Further, the controlling portion  100  can control the height of the placement portion  130  by transmitting a control signal to the driving device  121  of the expansion-contraction portion  120 . 
     The controlling portion  100  may control the movement of the autonomous mobile robot  10  by performing a well-known control such as a feedback control or a robust control based on rotation information or the like of the driving wheels  112  that is detected by respective rotation sensors provided in the driving wheels  112 . Further, the controlling portion  100  may autonomously move the autonomous mobile robot  10  by controlling the moving portion  110  based on information such as distance information detected by a range sensor or map information on the movement environment. The range sensor is, for example, a camera, an ultrasonic sensor, or the like provided in the autonomous mobile robot  10 . In the present embodiment, the controlling portion  100  controls the autonomous mobile robot  10  such that the autonomous mobile robot  10  moves to a predetermined position near the installation position of the trash box  2 , that is, the collecting position (e.g., a position right under the opening-closing portion  23 ) to collect the trash  31  in the trash box  2 . Then, the controlling portion  100  controls the autonomous mobile robot  10  such that the autonomous mobile robot  10  moves to a predetermined place when the autonomous mobile robot  10  receives the trash  31  dropped from the discharge port  22  of the trash box main body  20 . Hereby, the trash  31  is carried by the autonomous mobile robot  10  to the predetermined place. Note that the autonomous mobile robot  10  may grasp completion of receipt of the trash  31  by a signal from a sensor such as weight sensor configured to weighing the placement portion  130  or may grasp completion of receipt of the trash  31  by a notification transmitted from other devices such as the trash box  2 . 
     Next will be described one example of the operation of the trash box  2  according to the present embodiment.  FIG. 8  is a flowchart illustrating an example of the operation of the trash box  2  according to the present embodiment. The following description is made along  FIG. 8 . 
     In step S 100 , whether or not an object approaches the trash box  2  is detected. When the object approaches the trash box  2 , it is determined in step S 101  whether the object thus approaching the trash box  2  is a person or not. In a case where the object thus approaching the trash box  2  is a person, the process proceeds to step S 102 . On the other hand, in a case where the object thus approaching the trash box  2  is not a person, the process proceeds to step S 103 . In step S 102 , the slider driving device  253  changes the state of the trash box main body  20  to the lowered state. Note that, in a case where the trash box main body  20  is already in the lowered state, the process in step S 102  is omitted. On the other hand, in step S 103 , it is determined whether the object thus approaching the trash box  2  is the autonomous mobile robot  10  or not. In a case where the object thus approaching the trash box  2  is the autonomous mobile robot  10 , the process proceeds to step S 104 . On the other hand, in a case where the object thus approaching the trash box  2  is not the autonomous mobile robot  10 , the process is ended. In step S 104 , the slider driving device  253  changes the state of the trash box main body  20  to the raised state. Note that, in a case where the trash box main body  20  is already in the raised state, the process in step S 104  is omitted. After step S 104 , it is determined in step S 105  whether the position of the autonomous mobile robot  10  is the collecting position or not. When the autonomous mobile robot  10  arrives at the collecting position, the process proceeds to step S 106 . In step S 106 , the opening-closing portion  23  is opened. Hereby, the trash  31  accommodated in the trash box main body  20  falls down, so that the trash  31  is placed on the autonomous mobile robot  10 . That is, the trash  31  is placed on the placement portion  130  of the autonomous mobile robot  10  or the collection box  30  on the placement portion  130 . Accordingly, even in a case where the autonomous mobile robot  10  does not include arms having a complicated configuration, the autonomous mobile robot  10  can easily collect the trash. After that, in step S 107 , the opening-closing portion  23  is closed. 
     As described above, the trash box main body  20  of the trash box  2  according to the present embodiment is changeable in height from the reference plane  32 . Accordingly, a state suitable for the autonomous mobile robot  10  to collect the trash  31  from the lower side of the trash box main body  20  and a state suitable for people to put trash into the trash box  2  can be both achieved. That is, collection of the trash  31  by the autonomous mobile robot  10  from the lower side of the trash box main body  20  can be balanced with convenience for a user who puts the trash  31  into the trash box  2  (that is, the trash box main body  20 ). Note that, in the embodiment, the trash box main body  20  is changeable between the first state where the trash box main body  20  is distanced from the reference plane  32  at the predetermined distance and the second state where the distance between the trash box main body  20  and the reference plane  32  is shorter than the predetermined distance. However, the trash box main body  20  may be changeable between the first state where the trash box main body  20  is distanced from the reference plane  32  at the predetermined distance and a third state where the distance between the trash box main body  20  and the reference plane  32  is longer than the predetermined distance. Hereby, the height of the trash box main body  20  can be set to a height suitable for the autonomous mobile robot  10  to collect the trash  31  or to a height higher than that and suitable for people to put trash into the trash box main body  20 . 
     Further, in the above embodiment, the height of the trash box main body  20  is changed automatically by the slider driving device  253 , but the trash box  2  may not necessarily include a constituent configured to automatically change the height of the trash box main body  20 . That is, the height of the trash box main body  20  may be changed manually. 
     Further, the slider driving device  253  changes the height of the trash box main body  20  based on a detection result on the approach of a person or the autonomous mobile robot  10  as a trigger, but other triggers may be used. For example, the slider driving device  253  may change the height of the trash box main body  20  in response to a recognition result of a gesture or a voice of a person. More specifically, in a case where the sensor  24  or the like detects a predetermined gesture that instructs to change the state of the trash box main body  20  to the raised state, the slider driving device  253  may raise the trash box main body  20 . Similarly, in a case where the sensor  24  or the like detects a predetermined gesture that instructs to change the state of the trash box main body  20  to the lowered state, the slider driving device  253  may lower the trash box main body  20 . Further, in a case where a sensor configured to perform voice recognition (e.g., a microphone and a voice recognition processor) or the like detects a predetermined voice that instructs to change the state of the trash box main body  20  to the raised state, the slider driving device  253  may raise the trash box main body  20 . Similarly, in a case where the sensor configured to perform voice recognition or the like detects a predetermined voice that instructs to change the state of the trash box main body  20  to the lowered state, the slider driving device  253  may lower the trash box main body  20 . Further, the slider driving device  253  may change the height of the trash box main body  20  in response to an operation to an operating portion that is a switch (e.g., a button, a lever, or the like) provided in the trash box  2  and operated by physical force (physical contact). Note that the slider driving device  253  may use only either one of the triggers or may use some of the triggers. 
     Note that the disclosure is not limited to the above embodiments, and various modifications can be made within a range that does not deviate from the gist of the disclosure. For example, in the above embodiment, the position of the autonomous mobile robot  10  is detected by use of the sensor  24  included in the trash box  2 , but this detection may be performed based on a notification received by the trash box  2  from other devices. For example, this notification may be a notification transmitted from the autonomous mobile robot  10  to notify the position of the autonomous mobile robot  10 , a notification transmitted from a server configured to manage the position of the autonomous mobile robot  10 , or a notification transmitted from a sensor or the like provided on the reference plane  32  or the like. Further, the opening-closing portion  23  may be opened when a switch provided in the trash box  2  so as to open the opening-closing portion  23  is operated. This switch may be a button or a lever to be operated by physical force (physical contact). Further, the switch may be provided on the bottom surface of the trash box main body  20  and may be operated by the autonomous mobile robot  10  by use of the placement portion  130 .