Patent Publication Number: US-2020298408-A1

Title: Robot system

Description:
TECHNICAL FIELD 
     The present disclosure relates to a robot system. 
     BACKGROUND ART 
     Conventionally, a remote control robot system capable of causing a robot to perform a necessary work by an operator remotely manipulating the robot in a work environment is known. 
     For example, Patent Document 1 proposes a robot system capable of switching an operation mode from an automatic operation mode in which a robot is operated according to a preset task program to a manual operation mode in which an operator manipulates the robot by manually operating a user interface, such as a master arm. This system is possible, when an abnormality, such as the program prepared beforehand is not able to cause the robot to perform a given work, to cause the robot to perform the work by switching the operation mode from the automatic operation mode to the manual operation mode. 
     REFERENCE DOCUMENT OF CONVENTIONAL ART 
     Patent Document 
     [Patent Document 1] JP2003-311661A 
     DESCRIPTION OF THE DISCLOSURE 
     Problems to be Solved by the Disclosure 
     Meanwhile, for example, when a target work ranges a wide variety of operations or the target work requires a plurality of operation processes, it is efficient to prepare tens of robots which carry out the operations or processes simultaneously. However, when the system described above is applied to the plurality of robots, the same number of user interfaces as the robots must be prepared in order for operators to perform the manual operation. 
     Therefore, the present disclosure aims at providing a robot system suitable for remotely controlling a plurality of robots. 
     SUMMARY OF THE DISCLOSURE 
     In order to solve the above problems, a robot system according to the present disclosure includes a plurality of robot bodies, a plurality of operation devices, each configured to accept operation and generate operational information for causing the robot body to operate, a plurality of motion controllers provided corresponding to the plurality of robot bodies, respectively, and configured to control operation of the corresponding robot body in response to the operational information, a plurality of operation target selectors provided corresponding to the plurality of operation devices, respectively, and configured to receive an operation for selecting any of the plurality of robot bodies and request a permission to operate the selected robot body based on the operation information from the corresponding operation device, as a target to be operated, and an operation permitting device having a determinator configured to receive the permission request from the operation target selector and determine whether a permission is to be granted for the permission request, and when the determinator grants the permission, enable the operation of the selected robot body based on the operation information from the corresponding operation device. When the permission request is received from the operation target selector, and the operation of the robot body selected by the operation target selector based on the operational information from a different operation device from the operation device corresponding to the operation target selector is permitted, the determinator prohibits the permission to the permission request, or otherwise, grants the permission to the permission request. 
     According to this configuration, for example, even when an abnormality occurs to some of the plurality of robots and the operation is to be switched to the manual operation, it is possible to operate all the robots from one operation device, if the permission is granted from the operation permitting device. Therefore, it becomes unnecessary to prepare the same number of operation devices for the operators to manipulate the robot bodies as the number of robot bodies. 
     Moreover, in response to the reception of the permission request from the operation target selector, when the robot body selected by the operation target selector is permitted to operate based on the operational information from a different operation device from the operation device corresponding to the operation target selector, the permission to the permission request is prohibited. Thus, it is avoidable that one robot body is simultaneously manipulated from the plurality of operation devices. 
     Therefore, the robot system suitable for remotely controlling a plurality of robots, can be provided. 
     The robot system may include a plurality of request generators provided corresponding to the plurality of motion controllers, respectively, and configured to generate an operation request for requesting the operation information, and a request informer configured to inform that the request generator generates the operation request. According to this configuration, the operator is able to immediately know for which motion controller the operation request is generated. 
     The robot system may include a memory configured to store automatic operational information for causing the robot body to operate automatically. Before the request generator generates the operation request, an operation mode of the motion controller may be an automatic mode in which the operation of the robot body is controlled using the automatic operational information, and when the request generator generates the operation request, the operation mode may be switched from the automatic mode to a manual mode in which the operation of the robot body is controlled using the operational information. 
     The robot system may include a memory configured to store automatic operational information for causing the robot body to operate automatically. While the robot body operates automatically using the automatic operational information stored in the memory, the motion controller may control the operation of the robot body by using both the automatic operational information and the operational information, when the operational information is received from the operation device. 
     The operation device may be configured to be specifiable of a workpiece that is an object to be worked by the robot body, and the operational information may include workpiece information specified by the operation device. The motion controller may control the corresponding robot body in response to the operational information so that the robot body operates to perform a work to the workpiece specified by the operation device. 
     Effect of the Disclosure 
     The present disclosure can provide the robot system suitable for remotely controlling a plurality of robots. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic diagram illustrating a configuration of a robot system according to a first embodiment. 
         FIG. 2  is a view illustrating a configuration of a slave arm provided with an end effector. 
         FIG. 3  is a view illustrating a plurality of slave arms and a work environment for the slave arms. 
         FIG. 4  is a view illustrating an environment of operators stationed at operator interface systems. 
         FIG. 5  is a schematic diagram illustrating a configuration of a control system of the robot system illustrated in  FIG. 1 . 
         FIG. 6  is a view illustrating one example of a block diagram of the control system of a motion controller illustrated in  FIG. 5 . 
         FIG. 7  illustrates one example of an image displayed on a second monitoring device. 
         FIG. 8  is a view illustrating a robot body according to another embodiment. 
     
    
    
     MODES FOR CARRYING OUT THE DISCLOSURE 
     First Embodiment 
     Hereinafter, a robot system according to a first embodiment of the present disclosure is described with reference to the drawings. A robot system  100  according to this embodiment is a system utilizing a robot of a master-slave type. In the robot system  100 , as an operator who is located at a position distant from a workspace of a slave arm  1  (outside the workspace) moves a master arm  2  (see  FIG. 4 ) to input an instruction, the slave arm  1  moves corresponding to the instruction to perform a specific work. Moreover, in the robot system  100 , the slave arm  1  can also automatically perform a given work, without the operator&#39;s operation of the master arm  2 . 
     An operation mode in which the slave arm  1  is operated according to the instruction inputted through the master arm  2  is herein referred to as a “manual mode.” Note that the “manual mode” also includes a case where a part of the operation of the slave arm  1  under operation based on the instruction inputted by the operator operating the master arm  2  is automatically corrected. Moreover, an operation mode in which the slave arm  1  is operated according to the preset task program is referred to as an “automatic mode.” 
     Further, the robot system  100  of this embodiment is configured to be able to correct operation of the slave arm  1  to be carried out automatically during the automatic operation of the slave arm  1  by reflecting the manipulation of the master arm  2  to the automatic operation of the slave arm  1 . An operation mode in which the slave arm  1  is operated according to the preset task program in a state where the instruction inputted through the master arm  2  can be reflected to the operation of the slave arm  1  is herein referred to as a “correctable automatic mode.” Note that the “automatic mode” is distinguished from the “correctable automatic mode” in that the operation of the master arm  2  is not reflected to the operation of the slave arm  1  when the operation mode in which the slave arm  1  is operated is the automatic mode. 
     First, referring to  FIG. 1 , a configuration of the robot system  100  according to this embodiment is described.  FIG. 1  is a schematic diagram illustrating one example of the configuration of the robot system  100  according to this embodiment. As illustrated in  FIG. 1 , the robot system  100  includes a plurality of slave robots  10 , and a plurality of operator interface systems  20  including the respective master arms  2 . As illustrated in  FIG. 1 , as one example, the robot system  100  of this embodiment includes six slave robots  10  and four operator interface systems  20 . Note that the number of slave robots  10  and the number of operator interface systems  20  provided to the robot system  100 , are not limited to the number of this configuration. Moreover, these six slave robots  10  and four operator interface systems  20  are connected to an operation permitting device  8 , which will be described later. Below, each component of the robot system  100  is described in detail. 
     (Configuration of Slave Robot) 
     As illustrated in  FIG. 1 , each slave robot  10  includes a slave arm  1 , an end effector  16  attached to a tip end of the slave arm  1 , and a control device  3  which governs operation of the slave arm  1  and the end effector  16 . The slave arm  1  and the end effector  16  correspond to a “robot body” of the present disclosure. In this embodiment, although all the six slave robots  10  have the same configuration, they may have different configurations. 
       FIG. 2  is a view illustrating a configuration of the slave arm with the end effector  16  attached. The slave arm  1  includes a pedestal  15 , an arm part  13  supported by the pedestal  15 , and a wrist part  14  which is supported at a tip end of the arm part  13  and to which the end effector  16  is attached. As illustrated in  FIG. 2 , the slave arm  1  is an articulated robotic arm having six joints JT 1 -JT 6 , and is constructed by sequentially coupling a plurality of links  11   a - 11   f . In more detail, at the first joint JT 1 , the pedestal  15  and a base-end part of the first link  11   a  are coupled to each other rotatably on an axis extending in the vertical direction. At the second joint JT 2 , a tip-end part of the first link  11   a  and a base-end part of the second link  11   b  are coupled to each other rotatably on an axis extending in the horizontal direction. At the third joint JT 3 , a tip-end part of the second link  11   b  and a base-end part of the third link  11   c  are coupled to each other rotatably on an axis extending in the horizontal direction. At the fourth joint JT 4 , a tip-end part of the third link  11   c  and a base-end part of the fourth link  11   d  are coupled to each other rotatably on an axis extending in the longitudinal direction of the fourth link  11   c . At the fifth joint JT 5 , a tip-end part of the fourth link  11   d  and a base-end part of the fifth link  11   e  are coupled to each other rotatably on an axis perpendicular to the longitudinal direction of the link  11   d . At the sixth joint JT 6 , a tip-end part of the fifth link  11   e  and a base-end part of the sixth link  11   f  are rotatably coupled to each other in a twisted fashion. 
     A mechanical interface is provided to a tip-end part of the sixth link  11   f . An end effector  16  corresponding to the type of work is detachably attached to the mechanical interface. In this embodiment, the end effector  16  is a hand capable of holding a workpiece W described later (see  FIG. 7 ). 
     Moreover, in this embodiment, a first camera device  17  is provided to a tip end of the slave arm  1 . The first camera device  17  is supported by a part of the slave arm  1  near the tip end, for example, by a support part  18  fixed to the sixth link  11   f . The first camera device  17  is disposed so as to be oriented in a direction extending from the sixth joint JT 6  to the end effector  16 . That is, the first camera device  17  is disposed so as to image the workpiece W which is an object to be held by the end effector  16 , before and after holding. 
     The arm part  13  of the slave arm  1  is comprised of a coupling body of the links and joints, including the first joint JT 1 , the first link  11   a , the second joint JT 2 , the second link  11   b , the third joint JT 3 , and the third link  11   c , described above. Moreover, the wrist part  14  of the slave arm  1  is comprised of a coupling body of the links and joints, including the fourth joint JT 4 , the fourth link  11   d , the fifth joint JT 5 , the fifth link  11   e , the sixth joint JT 6 , and the fourth link  11   f , described above. 
     The joints JT 1 -JT 6  are each provided with a drive motor M (see  FIG. 6 ) as one example of an actuator which relatively rotates two members connected through the joint. For example, the drive motor M is a servo motor which is servo-controlled by the control device  3 . Moreover, the joints JT 1 -JT 6  are each provided with a rotation sensor E (see  FIG. 6 ) for detecting a rotational position of the drive motor M, and a current sensor C (see  FIG. 6 ) for detecting current which controls the rotation of the drive motor M. For example, the rotation sensor E is an encoder. 
       FIG. 3  is a view illustrating a plurality of slave arms  1  and a work environment for the slave arms. In this embodiment, for example, the slave arms  1  are disposed near respective shelves  19  provided in a warehouse. Each slave arm  1  performs a work to hold the workpiece W in the container placed on the shelf  19  one by one and to take out the workpiece W from the container. 
     For example, the control device  3  illustrated in  FIG. 1  includes a processor (not illustrated), such as a microcontroller, an MPU, a PLC (Programmable Logic Controller), or a logic circuit, and a memory  6  comprised of such as a ROM and a RAM. The control device  3  is provided with a motion controller  31  and a request generator  32  (see  FIG. 5 ) as its functional blocks. For example, these functional blocks are implemented by the processor of the control device  3  reading and executing a program stored in the memory  6 . The motion controller  31  controls operation of the slave arm  1  in response to operation information from the corresponding master arm  2  which will be described later. The request generator  32  generates an operation request for requesting the operation information. These will be described later in detail. 
     (Configuration of Operator Interface System) 
     Next, the operator interface systems  20  are described with reference to  FIG. 4 .  FIG. 4  is a view illustrating an environment of the operators stationed at the operator interface systems  20 . Each operator interface system  20  includes the master arm  2  described above, an input device  7 , and a first monitoring device  4 . The first monitoring device  4  is a monitor for displaying an image which is imaged by the first camera device  17 . In this embodiment, although the four operator interface systems  20  have the same configuration, they may have different configurations. 
     The master arm  2  is a device which is installed outside the workspace of the slave arm  1  and accepts an operational instruction from the operator. Since the master arm  2  has a similarity structure to the slave arm  1 , description of the configuration of the master arm  2  is omitted. However, the master arm  2  may have a non-similarity structure to the slave arm  1 . The operational information is generated by moving the master arm  2 , and the generated operational information is sent to the control device  3  through the operation permitting device  8 . In the robot system  100  of this embodiment, when the operational information is sent to the control device  3  while the operation mode in which the slave arm  1  is operated is the manual mode, the slave arm  1  is controlled by the control device  3  so that it follows the motion of the master arm  2 . When the operational information is sent to the control device  3  while the operation mode in which the slave arm  1  is operated is the correctable automatic mode, the operation of the slave arm  1  in the middle of the automatic operation is corrected using the operational information. The master arm  2  corresponds to an “operation device” of the present disclosure. 
     The input device  7  is installed outside the workspace together with the master arm  2 , and accepts the operational instruction from the operator. The input device  7  is configured to be operable, and, for example, it includes a switch, an adjustment knob, a control lever, or a potable terminal such as a tablet computer. The input device  7  includes an operation target selector  71 , a mode selector  72 , and an operational information selector  73 . 
     The operation target selector  71  accepts an operation for selecting one from the plurality of slave arms  1 . Thus, it requests, the operation permitting device  8  described later, for a permission to operate the selected slave arm  1  as an operation target based on the operational information from the corresponding master arm  2 . The mode selector  72  and the operational information selector  73  will be described later in detail. 
     (Second Camera Device and Second Monitoring Device) 
     Returning to  FIG. 1 , the robot system  100  further includes a plurality of (in the illustrated example, six) second camera devices  51 , and the second monitoring device  52 . As illustrated in  FIG. 1 , the six second camera devices  51  are provided corresponding to the six slave robots  10 . Each second camera device  51  is installed in the space where the corresponding slave arm  1  is provided. Each second camera device  51  is disposed at a position slightly distant from the slave arm  1  so that it images a work situation of the corresponding slave robot  10 . 
     The six second camera devices  51  are all connected to the second monitoring device  52 . The second camera device  51  and the second monitoring device  52  may not be directly connected to each other, or may be connected through another device. Moreover, the second camera device  51  and the second monitoring device  52  may be connected to each other wiredly or wirelessly. 
     The second monitoring device  52  is a monitor for the operators confirming the work situations of the slave arms  1 . The second monitoring device  52  is installed in the space where the master arm  2  is provided, and at a position which is visible from each operator who operates the corresponding operator interface system  20 . As illustrated in  FIG. 4 , the second monitoring device  52  includes six display parts  53 , six request informers  54 , and six connection informers  55 , corresponding to the six slave robots  10 . 
     The images imaged by the six second camera devices  51  are displayed on the six display parts  53 , respectively. Therefore, the operator can confirm the operations of the six slave arms  1  at once by watching the second monitoring device  52 . 
     The request informer  54  receives the operation request from the request generator  32  of the control device  3 , and informs that the request generator  32  generated the operation request. As illustrated in  FIG. 4 , in this embodiment, the request informer  54  is provided above the corresponding display part  53 . Moreover, in this embodiment, the request informer  54  is a light emitter. By receiving the operation request from the control device  3 , the request informer  54  corresponding to the control device  3  lights or blinks. Therefore, the operator is informed that there is an operation request from the slave robot  10  corresponding to the request informer  54 . 
     The connection informer  55  informs a connection relation between the slave robot  10  and the operator interface system  20 . In more detail, the manipulation of the slave robot  10  from the operator interface system  20  becomes possible when permission is granted from the operation permitting device  8 . When the operation permitting device  8  permits the operation of the slave robot  10 , the connection informer  55  corresponding to this slave robot  10  informs the operator interface system  20  of which the operation of the slave robot  10  is enabled. 
     As illustrated in  FIG. 4 , in this embodiment, the connection informer  55  is a liquid crystal display provided below the corresponding display part  53 , and displays the corresponding operator interface system  20  so as to be distinguishable from others. For example, in  FIG. 4 , “D” is displayed on the connection informer  55  corresponding to the request informer  54  denoting the number “2.” This means that the operator interface system  20  corresponding to the indication of “D”, and the slave robot  10  corresponding to the request informer  54  denoting the number “2” are connected to each other. 
     (Operation Permitting Device) 
     In this embodiment, the operation permitting device  8  has a determinator  81  which receives the permission request from the operation target selector  71  of the input device  7 , and determines whether the permission is to be granted for the permission request. The operation permission device  8  enables the operation of the selected slave robot  10  based on the operational information from the corresponding master arm  2 , when the determinator  81  grants the permission. 
       FIG. 5  is a schematic diagram illustrating a configuration of a control system of the robot system  100 . Note that, in  FIG. 5 , internal configurations of only one slave robot  10  and one operator interface system  20 (A) are illustrated, and other slave robots  10  and other operator interface systems  20 (B-D) are omitted. Moreover, the end effector  16  is also omitted in  FIG. 5 . 
     When the permission request is received from the operation target selector  71 , and the operation of the slave robot  10  selected by the operation target selector  71  based on the operational information from a master arm  2  different from the master arm  2  corresponding to the operation target selector  71  is permitted, the determinator  81  prohibits the permission to the permission request, or otherwise, it grants the permission to the permission request. 
     In detail, when the determinator  81  issues the permission to the permission request from the operation target selector  71 , the operational information generated by the master arm  2  of the operator interface system  20  including this operation target selector  71  is sent to the motion controller  31  of the slave robot  10  selected by the operation target selector  71 . Moreover, when the determinator  81  permits the operation of the slave robot  10 , it sends to the connection informer  55  information for identifying the operator interface system  20  which is now enabled to manipulate the slave robot  10 . 
     Moreover, when the determinator  81  issues the permission to the permission request from the operation target selector  71 , the image from the first camera device  17  which images the slave robot  10  selected by the operation target selector  71  is sent to the first monitoring device  4  of the operator interface system  20  including the operation target selector  71 . 
     Moreover, when the determinator  81  issues the permission to the permission request from the operation target selector  71 , the operational instruction to the mode selector  72  and the operational information selector  73  of the operator interface system  20  including the operation target selector  71  is sent to the motion controller  31  of the slave robot  10  selected by the operation target selector  71 . 
     Moreover, when the determinator  81  issues the permission to the permission request from the operation target selector  71 , the operational instruction to the mode selector  72  and the operational information selector  73  of the operator interface system  20  including the operation target selector  71  is sent to the motion controller  31  of the slave robot  10  selected by the operation target selector  71 . 
     Note that, although in  FIG. 5  each element (e.g., the master arm  2 ) of the operator interface system  20  and the element (e.g., the motion controller  31 ) of the control device  3  are connected with each other by the mechanical switch, this configuration is only illustrated schematically, and therefore, the present disclosure is not limited to this configuration. 
     As illustrated in  FIG. 5 , the mode selector  72  is for the operator to select the operation mode in which the slave arm  1  is operated from the automatic mode, the correctable automatic mode, and the manual mode described above. The operational information selector  73  is to select operational information used by the motion controller  31  when operating the slave arm  1  in the automatic mode or the correctable automatic mode from a plurality of operational information for operating the slave arm  1 . 
     The memory  6  of the control device  3  is a readable and writable recording medium, and information for causing the slave arm  1  to automatically perform a given operation is stored as the stored operational information  61 . The stored operational information  61  does not need to be all the information required for causing the slave arm  1  to automatically perform the given operation, and may be a part of the information. Moreover, the stored operational information  61  may be any kind of information as long as it is information related to the operation of the slave arm  1 . For example, the stored operational information  61  may be orbital information including time series data of rotational positions of the drive motor M, or may be path information indicative of the postures of the slave arm  1  (the rotational positions of the drive motor M) at intermittent time points of a given time interval. For example, the stored operational information  61  may include a speed of the slave arm  1  along the orbit. 
     At least one stored operational information  61  is stored in the memory  6 , and, for example, one of the stored operational information is teaching information  61   a  which is stored by operating the slave arm  1  so that the slave arm  1  performs a given work by this teaching operation. Although in this embodiment the stored operational information  61  as the teaching information  61   a  is information which is stored by operating the master arm  2  to instruct the operation of the slave arm  1 , it is not limited to this configuration but may be stored by using any kind of teaching methods. For example, the stored operational information  61  as the teaching information  61   a  may be information stored by using direct teaching. Note that although in the robot system  100  according to this embodiment the memory  6  is provided integrally with the control device  3 , but it may be provided separately from the control device  3 . 
     Below, a control of the operation of the slave arm  1  by the motion controller  31  is described with reference to  FIG. 5 . 
     One of the at least one stored operational information  61  stored in the memory  6  is sent to the motion controller  31  as automatic operational information for causing the slave arm  1  to operate automatically. Moreover, the operational information generated by operating the master arm  2  is sent to the motion controller  31 . 
     The motion controller  31  uses one or both of the automatic operational information and the operational information according to the operation mode selected by the mode selector  72 . 
     When the operation mode selected by the mode selector  72  is the manual mode, the motion controller  31  uses the operational information. In more detail, when the operation mode in which the slave arm  1  is operated is the manual mode, the motion controller  31  does not use the stored operational information  61  in the memory  6 , but controls the operation of the slave arm  1  according to the operational information (inputted instruction) sent by operating the master arm  2 . 
     Moreover, when the operation mode selected by the mode selector  72  is the automatic mode, the motion controller  31  uses the automatic operational information. In more detail, when the operation mode in which the slave arm  1  is operated is the automatic mode, the motion controller  31  does not use the operational information sent from the master arm  2 , but controls the operation of the slave arm  1  using the automatic operational information sent from the memory  6  according to the preset task program. 
     Moreover, when the operation mode selected by the mode selector  72  is the correctable automatic mode, the motion controller  31  uses both the automatic operational information and the operational information. Note that, when the operation mode is the correctable automatic mode and the operational information is not sent to the motion controller  31 , the motion controller  31  uses only the automatic operational information. In more detail, when the operation mode in which the slave arm  1  is operated is the correctable automatic mode, the motion controller  31  controls the operation of the slave arm  1  using both the automatic operational information and the operational information in response to the operational information received while the slave arm  1  is operating automatically using the automatic operational information. Therefore, the slave arm  1  performs operation related to the automatic operational information, i.e., operation corrected from the operation which is to be performed automatically. 
     Below, the correction of the operation of the slave arm  1  when the operation mode in which the slave arm  1  is operated is the corrected automatic operation mode is described with reference to  FIG. 6 .  FIG. 6  is a view illustrating one example of a block diagram of the control system of the motion controller  31 . 
     The motion controller  31  includes an adder  31   a , subtracters  31   b ,  31   e  and  31   g , a position controller  31   c , a differentiator  31   d , and a speed controller  31   f , and controls the rotational position of the drive motor M of the slave arm  1  according to an instruction value based on the automatic operational information and an instruction value based on the operational information. 
     The adder  31   a  generates a positional instruction value which is corrected by adding the correction instruction value based on the operational information to the positional instruction value based on the automatic operational information. The adder  31   a  sends the corrected positional instruction value to the subtracter  31   b.    
     The subtracter  31   b  subtracts a present position value detected by the rotation sensor E from the corrected positional instruction value to generate an angular deviation. The subtracter  31   b  sends the generated angular deviation to the position controller  31   c.    
     The position controller  31   c  generates a speed instruction value from the angular deviation sent from the subtracter  31   b  by using calculation processing based on a given transfer function and a given proportionality coefficient. The position controller  31   c  sends the generated speed instruction value to the subtracter  31   e.    
     The differentiator  31   d  differentiates the present position value information detected by the rotation sensor E to generate an amount of change in the rotational angle of the drive motor M per unit time, i.e., a present speed value. The differentiator  31   d  sends the generated present speed value to the subtracter  31   e.    
     The subtracter  31   e  subtracts the present speed value sent from differentiator  31   d  from the speed instruction value sent from the position controller  31   c  to generate a speed deviation. The subtracter  31   e  sends the generated speed deviation to the speed controller  31   f.    
     The speed controller  31   f  generates a torque instruction value (current instruction value) from the speed deviation sent from the subtracter  31   e  by using a calculation processing based on a given transfer function and a given proportionality coefficient. The speed controller  31   f  sends the generated torque instruction value to the subtracter  31   g.    
     The subtracter  31   g  subtracts the present current value detected by the current sensor C from the torque instruction value sent from the speed controller  31   f  to generate a current deviation. The subtracter  31   g  sends the generated current deviation to the drive motor M to drive the drive motor M. 
     Thus, the motion controller  31  controls the drive motor M to control the slave arm  1  so that the slave arm  1  performs the operation corrected from the operation related to the automatic operational information. Note that, when the operation mode of the slave arm  11  is the automatic mode, the positional instruction value based on the automatic operational information is sent to the subtracter  31   b , and when the operation mode of the slave arm  11  is the manual mode, the positional instruction value based on the operational information is sent to the subtracter  31   b.    
     When the slave arm  1  performs the corrected operation, the memory  6  automatically stores the corrected operational information for causing the slave arm  1  to perform the corrected operation, as the stored operational information  61 . However, when the slave arm  1  performs the corrected operation, the memory  6  may be selectable of whether the corrected operational information is to be stored as the stored operational information  61 . In this case, for example, after the corrected operation of the slave arm  1  is finished, the control device  3  may inquire the input device  7  whether the corrected operation is to be stored. 
     The motion controller  31  can use the corrected operational information stored in the memory  6  as the stored operational information  61 , as automatic operational information for the subsequent operations. In this embodiment, the motion controller  31  controls the operation of the slave arm  1  by using the latest stored operational information  61  stored in the memory  6  as the automatic operational information. 
     Next, one example of a flow of operation of the robot system  100  according to this embodiment is described. As illustrated in  FIG. 3 , suppose that the six slave robots  10  perform the work to take out the workpiece W from the shelf  19  in the automatic mode. If some of the slave robots  10  (e.g., the slave robot  10  at the center of the upper row in  FIG. 2 ) illustrated in  FIG. 3  become impossible to continue the work due to a certain reason, the request generator  32  of this slave robot  10  generates an operation request for requesting the operational information. The operation request is sent to the request informer  54  corresponding to this slave robot  10 , and the request informer  54  then informs that there is an operation request from the request generator  32 . 
     In response to the notification from the request informer  54 , the operator operates the operation target selector  71  to select the slave robot  10  for which the operation request is issued. Thus, when the operation permitting device  10  grants permission to the permission request sent from the operation target selector  71 , image information is sent to the first monitoring device  4  from the first camera  17  which images the corresponding slave robot  10 . 
       FIG. 7  illustrates one example of the image displayed on the first monitoring device  4 . The operator manually operates the master arm  2  while watching the first monitoring device  4  to take out the workpiece W from the shelf by using the slave robot  10 . 
     Note that, in this embodiment, the operation mode of the motion controller is switched from the automatic mode to the manual mode or the correctable automatic mode at a timing where the request generator  32  generates the operation request. However, the timing at which the operation mode of the motion controller is switched is not limited to this configuration. For example when the operation permitting device  10  grants permission to the permission request sent from the operation target selector  71 , a screen for urging the operator to select any one of the manual mode, the automatic mode, and the correctable automatic mode may be displayed on the first monitoring device  4 . For this screen, the mode selector  72  may be operated to switch the operation mode. 
     Alternatively, the operator may operate not the master arm  2  but another operation device, while watching the first monitoring device  4 . For example, the operation device may be configured so that the workpiece W, such as a mouse, which is displayed on the first monitoring device  4  and is a work object may be specified. For example, the top workpiece may be specified among the workpieces W displayed on the first monitoring device  4 . The operational information may include workpiece information specified by the operation device, and the motion controller  71  may control the corresponding slave arm  1  so that this slave arm  1  automatically performs the work to the workpiece W specified by the operation device, in response to the operational information. 
     As described above, in the robot system  100  according to this embodiment, for example, even when an abnormality occurs to some of the plurality of slave robots  10  and the operation is to be switched to the manual operation, it is possible to operate all the slave robots  10  from one master arm  2 , if the permission is granted from the operation permitting device  8 . Therefore, it becomes unnecessary to prepare the same number of master arms  2  for the operators to operate the slave robots  10  as the number of slave robots  10 . 
     Moreover, in response to the reception of the permission request from the operation target selector  71 , when the slave robot  10  selected by the operation target selector  71  is permitted to operate based on the operational information from a different master arm  2  from the master arm  2  corresponding to the operation target selector  71 , the permission to the permission request is prohibited. Thus, it is avoidable that one slave robot  10  is simultaneously manipulated from the plurality of master arms. 
     Therefore, the robot system suitable for remotely manipulating the plurality of robots can be provided. 
     Moreover, in this embodiment, since the request generator  32  generates the operation request for requesting the operational information, and the request informer  54  informs that the operation request is generated by the request generator  32 , the operator is able to immediately know which slave robot  10  is requested by the operation request. 
     Moreover, in this embodiment, the operation of the slave arm  1  during operation is correctable on real time by using the master arm  2 . Therefore, a partial correction of the operation of the slave arm  1  can be performed easily. Moreover, since the corrected operational information for performing the corrected operation is stored in the memory  6  as the stored operational information, the slave arm  1  can automatically perform the corrected operation, without the necessity of performing the correction by performing the same operation each time using the master arm  2 . Therefore, the operation taught to the slave arm  1  is easily correctable. 
     Moreover, since in this embodiment the automatic mode is selectable by the mode selector  72  as the operation mode of the motion controller  31 , if the correction of the operation of the slave arm  1  is not needed, the automatic mode can be selected to prevent that the master arm  2  is operated unintentionally and the operation of the slave arm  1  is corrected. Moreover, since the manual mode is selectable by the mode selector  72  as the operation mode of the motion controller  31 , the slave arm  1  can be operated, without using the stored operational information  61  stored in the memory  6 . 
     Moreover, in this embodiment, since the motion controller  31  controls the operation of the slave arm  1  using the latest stored operational information stored in the memory  6  as the automatic operational information, each time the correction of the slave arm  1  is repeated using the master arm  2 , the operation of the slave arm  1  can be gradually brought close to the target operation. 
     The motion controller  31  does not necessarily use the latest stored operational information  61  stored in the memory  6  as the automatic operational information. For example, the operational information selector  73  may select the stored operational information  61  which is used by the motion controller  31  as the automatic operational information, from a plurality of stored operational information  61  stored in the memory  6 . In this case, the same stored operational information  61  may be used each time as the automatic operational information until another stored operational information  61  which is used as the automatic operational information is selected by the operational information selector  73 . According to this configuration, even when the latest stored operational information  61  stored in the memory  6  is not optimal as the information for operating the slave arm  1 , the operational information selector  73  can use the stored operational information  61  when the correction is made appropriately as the automatic operational information. 
     Moreover, the robot system  100  may be provided with a status information acquirer (not illustrated) which acquires status information indicative of a situation of the slave arm  1  in the workspace, and the motion controller  31  may select and use the stored operational information  61  suitable for operating the slave arm  1  as the automatic operational information based on the status information acquired by the status information acquirer. For example, the status information includes the position or the posture of the slave arm  1  in the workspace, or information utilized for recognizing the situation around the slave arm  1 . For example, the information utilized for recognizing the situation around the slave arm  1  is a time window or a timing where the slave arm  1  is operated, or temperature or humidity of the workspace. For example, when the slave robot  10  is a sealing robot which applies sealing agent with viscosity, the viscous resistance of the sealing agent may vary with working hours. In such a case, the stored operational information  61  suitable for the viscous resistance of the sealing agent is selected as the automatic operational information based on the status information, and therefore, the correction of the operation of the slave arm  1  can be made more easily. 
     Other Embodiments 
     The present disclosure is not limited to the embodiment described above, and various modifications are possible without departing from the spirit of the present disclosure. 
     For example, although in the above embodiment the articulated robotic arm having the six joints JT 1 -JT 6  is illustrated as the robot body of the present disclosure, the robot body of the present disclosure is not be limited to this configuration, and may have any kind of configuration.  FIG. 8  is a view illustrating a robot body  9  according to another embodiment. This robot body  9  includes a linear-motion part  92  which linearly moves along a pole  91  extending in the vertical direction, and an articulated robot  93  supported by the linear-motion part  92 . In this case, the motion controller of the present disclosure may control not only the operation of the articulated robot  93  but the operation of the linear-motion part  92  in the vertical direction. 
     Moreover, although in the above embodiment the master arm  2  is described as one example of the operation device of the present disclosure, the operation device of the present disclosure may have another configuration, such as a joystick, for example. 
     Moreover, the configurations of the request informer  54  and the connection informer  55  are not limited to the configurations described above. 
     For example, the request informer  54  may not be a light emitter, but may be a liquid crystal display which displays that there is a request. The request informer  54  and the connection informer  55  may not be provided to the second monitoring device  52 , and may be provided to each operator interface system  20 . 
     Moreover, although in the embodiment the operating parts, such as the mode selector  72  and the operational information selector  73  are provided to a single input device  7 , they may be provided to different input devices. 
     DESCRIPTION OF REFERENCE CHARACTERS 
     
         
           1 : Slave Arm 
           2 : Master Arm 
           3 : Control Device 
           4 : First Monitoring Device 
           6 : Memory 
           7 : Input Device 
           8 : Operation Permitting Device 
           10 : Slave Robot 
           11 : Slave Arm 
           16 : End Effector 
           17 : First Camera Device 
           31 : Motion Controller 
           32 : Request Generator 
           51 : Second Camera Device 
           52 : Second Monitoring Device 
           53 : Display Part 
           54 : Request Informer 
           71 : Operation Target Selector 
           81 : Determinator 
           100 : Robot System