Patent Publication Number: US-2021178597-A1

Title: Robot system that operates through a network firewall

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The subject matter disclosed generally relates to the field of mobile two-way teleconferencing. 
     2. Background Information 
     Robots have been used in a variety of applications ranging from remote control of hazardous material to assisting in the performance of surgery. For example, U.S. Pat. No. 5,762,458 issued to Wang et al. discloses a system that allows a surgeon to perform minimally invasive medical procedures through the use of robotically controlled instruments. One of the robotic arms in the Wang system moves an endoscope that has a camera. The camera allows a surgeon to view a surgical area of a patient. 
     Tele-robots such as hazardous waste handlers and bomb detectors may contain a camera that allows the operator to view the remote site. Canadian Pat. No. 2289697 issued to Treviranus, et al. discloses a teleconferencing platform that has both a camera and a monitor. The platform includes mechanisms to both pivot and raise the camera and monitor. The Treviranus patent also discloses embodiments with a mobile platform, and different mechanisms to move the camera and the monitor. 
     There has been marketed a mobile robot introduced by InTouch Technologies, Inc., the assignee of this application, under the trademark RP-7. The InTouch robot is controlled by a user at a remote station. The remote station may be a personal computer with a joystick that allows the user to remotely control the movement of the robot. Both the robot and remote station have cameras, monitors, speakers and microphones to allow for two-way video/audio communication. The robot camera provides video images to a screen at the remote station so that the user can view the robot&#39;s surroundings and move the robot accordingly. 
     The InTouch robot system typically utilizes a broadband network such as the Internet to establish a communication channel between the remote station and the robot. The robot can be located at a facility which has a firewall between the facility local network and the Internet. The firewall can inhibit remote access to the robot through the broadband network. It would be desirable to provide a system that would allow access to a remote robot that is protected by a local area network firewall. 
     BRIEF SUMMARY OF THE INVENTION 
     A remote controlled robot system that includes a robot and a remote control station that communicate through a communication network. The robot moves in response to robot control commands transmitted by the remote control station. The robot may be coupled to the communication network by a firewall. A communication server establishes communication between the robot and the remote control station. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an illustration of a robotic system; 
         FIG. 2  is a schematic of an electrical system of a communication server; 
         FIG. 3  is a schematic of an electrical system of a robot; 
         FIG. 4  is a further schematic of the electrical system of the robot; 
         FIG. 5  is an illustration of a robot; 
         FIG. 6  is a graphical user interface of a remote station. 
         FIG. 7  is an illustration of a robot head. 
     
    
    
     DETAILED DESCRIPTION 
     Disclosed is a remote controlled robot system that includes a robot and a remote control station that communicate through a communication network. Communication with the robot is limited by a firewall coupled to the communication network. A communication server establishes communication between the robot and the remote control station so that the station can send commands to the robot through the firewall. 
     Referring to the drawings more particularly by reference numbers,  FIG. 1  shows a robotic system  10  that can be used to conduct a remote visit. The robotic system  10  includes a robot  12 , a base station  14  and a remote control station  16 . The remote control station  16  may be coupled to the base station  14  through a network  18 . By way of example, the network  18  may be either a packet switched network such as the Internet, or a circuit switched network such has a Public Switched Telephone Network (PSTN) or other broadband system. The base station  14  may be coupled to the network  18  by a modem (not shown) or other broadband network interface device. By way of example, the base station  14  may be a wireless router. Alternatively, the robot  12  may have a direct connection to the network thru for example a satellite. 
     The remote control station  16  may include a computer  22  that has a monitor  24 , a camera  26 , a microphone  28  and a speaker  30 . The computer  22  may also contain an input device  32  such as a joystick or a mouse. The control station  16  is typically located in a place that is remote from the robot  12 . Although only one remote control station  16  is shown, the system  10  may include a plurality of remote stations. In general any number of robots  12  may be controlled by any number of remote stations  16  or other robots  12 . For example, one remote station  16  may be coupled to a plurality of robots  12 , or one robot  12  may be coupled to a plurality of remote stations  16 , or a plurality of robots  12 . 
     Each robot  12  includes a movement platform  34  that is attached to a robot housing  36 . Also attached to the robot housing  36  is a camera  38 , a monitor  40 , a microphone(s)  42  and a speaker(s)  44 . The microphone  42  and speaker  30  may create a stereophonic sound. The robot  12  may also have an antenna  46  that is wirelessly coupled to an antenna  48  of the base station  14 . The system  10  allows a user at the remote control station  16  to move the robot  12  through operation of the input device  32 . The robot camera  38  is coupled to the remote monitor  24  so that a user at the remote station  16  can view a subject such as a patient. Likewise, the robot monitor  40  is coupled to the remote camera  26  so that the patient can view the user. The microphones  28  and  42 , and speakers  30  and  44 , allow for audible communication between the patient and the user. 
     The remote station computer  22  may operate Microsoft OS software and WINDOWS XP or other operating systems such as LINUX. The remote computer  22  may also operate a video driver, a camera driver, an audio driver and a joystick driver. The video images may be transmitted and received with compression software such as MPEG CODEC. 
     The flow of information between the robot  12  and the control station  16  may be limited by a firewall  50  on the robot side of the system and/or a firewall  51  on the control station side of the system. By way of example, the robot  12  and/or control station  16  may be located at a facility that contains one or more firewalls that control communication between the facility local area network and the network  18 . The system  10  includes a communication server  52  that can establish communication between the robot  12  and the remote control station  16 . 
     The system may have the following hierarchy to establish communication between the robot  12  and the remote control station  16 . The remote control station  16  may transmit an initial request to access a robot  12  by transmitting one or more packets to an internal IP address of the robot  12 . It being understood that each robot may have a unique IP address. If the robot  12  is not on the same network as the remote station  16 , this communication will fail. 
     If the initial attempt to access the robot is unsuccessful with the internal IP address, the remote control station  16  may transmit a request to the robot&#39;s external IP address. This may be done in either TCP or UDP protocol. If this attempt is unsuccessful, for example if the firewall prevents access to the robot, the remote control station may send a query to the communication server  52  which can then establish communication between the remote station  16  and the robot  12 . 
     Many firewalls employ port address translation (“PAT”) to disguise an outgoing message. For example, if a device such as the robot sends a message with a source port number of 9000 the firewall  50 / 51  can change the source port number to 47501. The firewall  50 / 51  will then only allow incoming messages to pass through if addressed to the translated port (e.g., 47501). Additionally, the firewall  50 / 51  may also only allow incoming messages if the message packet came from a source port recently communicated to by the robot, and the destination port of the packet matches the source port of a packet recently received from the source. 
     Each robot  12  may establish a constant link with a communication port of the server  52 . Alternatively, each robot may periodically poll the server  52 . With either method the server knows the last known IP address of robots and control stations, as well as the peer to peer UDP ports open on each. Upon receiving a query from a remote control station  16 , the server  52  can forward both IP and port information on both the robot  12  and the remote station, so that both the remote station  16  and robot  12  can simultaneously send to peer to peer packets to each other, bypassing problems caused by PAT tables. The last known IP address may be the PAT address provided by the firewall  50 . Upon receiving a query from a remote control station  16 , the server  52  can forward the PAT address to the remote station  16 , so that the station  16  can establish a peer to peer communication with the robot  12 . 
     Alternatively, or in the event a peer to peer communication cannot be established, the server  52  can provide a conduit for communication between the remote control station  16  and the robot  12 . For example, packets directed to the communication server  52 , which then can be retransmits the packets to the robot  12  using the last known IP address. In this mode, the server  52  can establish UDP connectivity with both the remote control station  16  and the robot  12 . The server  52  instructs the robot  12  and the remote station  16  to open a UDP socket and transmit UDP packets to a specified server port. 
     The server  52  provides a conduit to allow communication between a plurality of control stations and a single robot, a single control station and a plurality of robots, or a plurality of control stations with a plurality of robots. 
       FIG. 2  shows an embodiment of a communication server  52 . The server may include one or more processors  60  connected to one or more memory devices  62 . The memory device  62  may include both volatile and non-volatile memory such as read only memory (ROM) or random access memory (RAM). The processor  60  is capable of operating software programs in accordance with instructions and data stored within the memory device  62 . 
     The processor  60  may be coupled to a communication port  64 , a mass storage device  66 , a monitor  68  and a keyboard  70  through a system bus  72 . The communication port  64  may include an ETHERNET interface that allows data to be transmitted and received in TCP/IP or UDP format. The system bus  72  may be PCI or another conventional computer bus. The mass storage device  66  may include one or more disk drives such as magnetic or optical drives. 
     Without limiting the scope of the invention the term computer readable medium may include the memory device  42  and/or the mass storage device  46 . The computer readable medium will contain software programs in binary form that can be read and interpreted by the computer. In addition to the memory device  62  and/or mass storage device  66 , computer readable medium may also include a diskette, a compact disc, an integrated circuit, a cartridge, or even a remote communication of the software program. 
     The server  52  may contain a number of graphical user interfaces that allow a user to control communication between the remote station and the robot. The server  52  can control robot access for a designated time period. For example, the server can limit the time a particular remote station can control a robot to two hours of access time. The server allows a system operator to charge a robot access fee or other form of compensation that is divisible by units of time. 
     In alternative embodiments, the server  52  may also be a network appliance rather than a full computer with an operating system. Alternatively, the server  52  may in fact be a distributed network of physical servers or network devices, each at different IP addresses, for which a given robot  12  and remote station  16  may be connected to different physical devices, and those physical devices share data about the systems connected to the devices. In cases where a server  52  is used as a data conduit, one of the following may occur: (a) either the robot  12  or remote station  16  is instructed to disconnect from one physical device and re-connect to the same physical device to which the other device is connected, or (b) the data within the server network is transmitted from one server to another as necessary. In addition, the server  52  may have a router, firewall or similar device, with sufficient port forwarding and/or packet management to effect the same behavior as if residing on the public internet, for purposes of communication with the robots  12  and remote stations  16 . 
       FIGS. 3 and 4  show an embodiment of a robot  12 . Each robot  12  may include a high level control system  150  and a low level control system  152 . The high level control system  150  may include a processor  154  that is connected to a bus  156 . The bus  156  is coupled to the camera  38  by an input/output (I/O) port  158 . The monitor  40  is coupled to the bus  156  by a serial output port  160  and a VGA driver  162 . The monitor  40  may include a touchscreen function that allows the patient to enter input by touching the monitor screen. 
     The speaker  44  is coupled to the bus  156  by a digital to analog converter  164 . The microphone  42  is coupled to the bus  156  by an analog to digital converter  166 . The high level controller  150  may also contain random access memory (RAM) device  168 , a non-volatile RAM device  170  and a mass storage device  172  that are all coupled to the bus  156 . The mass storage device  172  may contain medical files of the patient that can be accessed by the user at the remote control station  16 . For example, the mass storage device  172  may contain a picture of the patient. The user, particularly a health care provider, can recall the old picture and make a side by side comparison on the monitor  24  with a present video image of the patient provided by the camera  38 . The robot antennae  46  may be coupled to a wireless transceiver  174 . By way of example, the transceiver  174  may transmit and receive information in accordance with IEEE 802.11b. 
     The controller  154  may operate with a LINUX OS operating system. The controller  154  may also operate MS WINDOWS along with video, camera and audio drivers for communication with the remote control station  16 . Video information may be transceived using MPEG CODEC compression techniques. The software may allow the user to send e-mail to the patient and vice versa, or allow the patient to access the Internet. In general the high level controller  150  operates to control communication between the robot  12  and the remote control station  16 . 
     The remote control station  16  may include a computer that is similar to the high level controller  150 . The computer would have a processor, memory, I/O, software, firmware, etc. for generating, transmitting, receiving and processing information. The high level controller  150  may be linked to the low level controller  152  by serial ports  176  and  178 . The low level controller  152  includes a processor  180  that is coupled to a RAM device  182  and non-volatile RAM device  184  by a bus  186 . Each robot  12  contains a plurality of motors  188  and motor encoders  190 . The motors  188  can actuate the movement platform and move other parts of the robot such as the monitor and camera. The encoders  190  provide feedback information regarding the output of the motors  188 . The motors  188  can be coupled to the bus  186  by a digital to analog converter  192  and a driver amplifier  194 . The encoders  190  can be coupled to the bus  186  by a decoder  196 . Each robot  12  also has a number of proximity sensors  198  (see also  FIG. 1 ). The sensors  198  can be coupled to the bus  186  by a signal conditioning circuit  200  and an analog to digital converter  202 . 
     The low level controller  152  runs software routines that mechanically actuate the robot  12 . For example, the low level controller  152  provides instructions to actuate the movement platform to move the robot  12 . The low level controller  152  may receive movement instructions from the high level controller  150 . The movement instructions may be received as movement commands from the remote control station or another robot. Although two controllers are shown, it is to be understood that each robot  12  may have one controller, or more than two controllers, controlling the high and low level functions. 
     The various electrical devices of each robot  12  may be powered by a battery(ies)  204 . The battery  204  may be recharged by a battery recharger station  206  (see also  FIG. 1 ). The low level controller  152  may include a battery control circuit  208  that senses the power level of the battery  204 . The low level controller  152  can sense when the power falls below a threshold and then send a message to the high level controller  150 . 
       FIG. 5  shows an embodiment of the robot  12 . The robot  12  may include a holonomic platform  250  that is attached to a robot housing  250 . The holonomic platform  250  provides three degrees of freedom to allow the robot  12  to move in any direction. 
     The robot  12  may have a pedestal assembly  254  that supports the camera  38  and the monitor  40 . The pedestal assembly  254  may have two degrees of freedom so that the camera  38  and monitor  40  can together be swiveled and pivoted as indicated by the arrows. 
     The camera  38  and monitor  40  may in accordance with a closed loop control system. The platform  250  is located within a platform reference coordinate system that may have axes X p , Y p  and Z p . By way of example, the y-axis Y p  may extend from a nose of the platform  250 . The camera  38  is fixed to a camera reference coordinate system that may have axes X c , Y c  and Z c . The y-axis Y may extend perpendicular from the camera lens. When the robot is initialized, the y-axis Y c  of the camera coordinate system may be aligned with the y-axis Y p  of the platform coordinate system. A forward pivoting of the joystick  32  (shown in  FIG. 1 ) may cause a corresponding movement of the platform  250  in the direction of the y-axis Y p  in the platform coordinate system. 
     The robot may have a drive vector that may have axes X d , Y d , and Z d  that is mapped to the camera coordinate system, the platform coordinate system or some other system. By way of example, the y-axis Y p  may extend in the direction of forward motion. Mapping includes the process of transforming an input command into a directional movement relative to one or more coordinate systems. The robot controller may perform certain algorithms to translate input commands to platform movement in accordance with a specified mapping scheme. For example, when the drive vector is mapped to the camera coordinate system the controller computes the drive vector of the input command relative to the camera coordinate system. In a platform mapping scheme the input drive vector is computed relative to the platform coordinate system. In yet another scheme the drive vector can be computed relative to another coordinate system, such as a world coordinate system (e.g. coordinate system relative to the ground) that is independent of the camera or platform coordinate systems. Mapping the drive vector to the camera coordinate system may be desirable because all movement would be relative to the image viewed by the user, providing a system that is intuitive to use. 
     A twisting of the joystick  32  may cause the camera  38  to swivel as indicated by arrows  4 . For example, if the joystick  32  is twisted +45 degrees the camera  38  will pivot +45 degrees. Swiveling the camera  38  also moves the y-axis Y c  of the camera coordinate system, because the y-axis Y is fixed to the camera. This may be different than the drive direction. The remote station computer may operate a program to generate a command that will automatically rotate the platform  250  to realign the y-axis Y p  of the platform coordinate system with the y-axis Y c  of the camera coordinate system. For the above example, the platform  250  is rotated +45 degrees. This approach keeps the platform  250  aligned with the camera  38 , so that any subsequent movement of the robot will be intuitive relative to the image provided by the camera. For example, a forward pivot of the joystick will induce a forward movement of the robot as viewed through the monitor of the remote station. In this driving scheme, the platform may not be aligned with the head. The computer may generate trajectory planning for the platform coordinate system to move into alignment with the head coordinate system over a period of time or distance traveled, with or without an initial delay in time or some distance. 
     The system may be configured so that pivotal movement of the joystick  32  may be mapped to a corresponding directional movement of the robot. For example, pivoting the joystick along a +45 degree may cause the robot to move in a +45 degree direction relative to the y-axis Y c  of the camera coordinate frame. Alternatively, the camera may pan +45 degrees and the platform  250  may rotate +45 degrees before forward movement by the robot. The automatic panning and platform rotation causes the robot to move in a forward direction as depicted by the image provided by the camera. The robot may have a mode wherein the user can twist the joystick to pan the camera during robot movement such that the movement is not in the direction the camera is pointing. This allows the user to visually pan while moving the robot. The joystick may have a spring return that automatically returns the position of the stick when released by the user. This causes the camera to be aligned with the direction of movement. 
     In general the robot may have a number of different mapping schemes and relative, dependent or independent, movement between the camera, the platform and drive direction. Relative movement between the camera and platform may occur in a camera based mapping scheme, a platform based mapping scheme, or some other scheme. 
     Although, the automatic platform rotation commands have been described as be generated by the remote station computer, it is to be understood that the robot may determine the commands and signals necessary to re-orient the platform  250  and/or the camera  38 . The robot  12  may include a potentiometer (not shown) that tracks the position of the camera and provides feedback to the low level controller  180 . The low level controller  180  may automatically rotate the platform to align the y-axes Y c  and Y p  or otherwise compensate for camera movement. A mode button (not shown) may allow the operator to place the system in either a tracking mode or a normal mode. In the tracking mode the robot moves relative to the camera coordinate system so that movement is intuitive relative to the screen even when the camera is panned. In normal mode the robot moves within the platform coordinate system. 
     The system may be the same or similar to a robotic system provided by the assignee InTouch-Health, Inc. of Santa Barbara, Calif. under the name RP-7. The system may also be the same or similar to the system disclosed in U.S. Pat. No. 6,925,357 issued Aug. 2, 2005, which is hereby incorporated by reference. 
       FIG. 6  shows a display user interface (“DUI”)  300  that can be displayed at the remote station  16 . The DUI  300  may include a robot view field  302  that displays a video image provided by the camera of the robot. The DUI  300  may also include a station view field  304  that displays a video image provided by the camera of the remote station  16 . The DUI  300  may be part of an application program stored and operated by the computer  22  of the remote station  16 . The display user interface and the various features and functions provided by the interface may be the same or similar as the DUI provided by the RP-7 system. 
     In operation, the robot  12  may be placed in a home or a facility where one or more patients are to be monitored and/or assisted. The facility may be a hospital or a residential care facility. By way of example, the robot  12  may be placed in a home where a health care provider may monitor and/or assist the patient. Likewise, a friend or family member may communicate with the patient. The cameras and monitors at both the robot and remote control stations allow for teleconferencing between the patient and the person at the remote station(s). 
     The robot  12  can be maneuvered through the home or a facility by manipulating the input device  32  at a remote station  16 . The robot  10  may be controlled by a number of different users. To accommodate for this the robot may have an arbitration system. The arbitration system may be integrated into the operating system of the robot  12 . For example, the arbitration technique may be embedded into the operating system of the high-level controller  150 . 
     By way of example, the users may be divided into classes that include the robot itself, a local user, a caregiver, a doctor, a family member, or a service provider. The robot  12  may override input commands that conflict with robot operation. For example, if the robot runs into a wall, the system may ignore all additional commands to continue in the direction of the wall. A local user is a person who is physically present with the robot. The robot could have an input device that allows local operation. For example, the robot may incorporate a voice recognition system that receives and interprets audible commands. 
     A caregiver is someone who remotely monitors the patient. A doctor is a medical professional who can remotely control the robot and also access medical files contained in the robot memory. The family and service users remotely access the robot. The service user may service the system such as by upgrading software, or setting operational parameters. 
     The robot  12  may operate in one of two different modes; an exclusive mode, or a sharing mode. In the exclusive mode only one user has access control of the robot. The exclusive mode may have a priority assigned to each type of user. By way of example, the priority may be in order of local, doctor, caregiver, family and then service user. In the sharing mode two or more users may share access with the robot. For example, a caregiver may have access to the robot, the caregiver may then enter the sharing mode to allow a doctor to also access the robot. Both the caregiver and the doctor can conduct a simultaneous tele-conference with the patient. 
     The system  10  can be used for doctor proctoring where a doctor at the remote station provides instructions and feedback to a doctor located in the vicinity of the robot. For example, a doctor at the remote location can view a patient and assist a doctor at the patient location in a diagnosis. Likewise, the remote doctor can assist in the performance of a medical procedure at the robot location. 
     The arbitration scheme may have one of four mechanisms; notification, timeouts, queue and call back. The notification mechanism may inform either a present user or a requesting user that another user has, or wants, access to the robot. The timeout mechanism gives certain types of users a prescribed amount of time to finish access to the robot. The queue mechanism is an orderly waiting list for access to the robot. The call back mechanism informs a user that the robot can be accessed. By way of example, a family user may receive an e-mail message that the robot is free for usage. Tables I and II, show how the mechanisms resolve access request from the various users. 
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE I 
               
               
                   
               
               
                   
                 Access 
                 Medical 
                 Command 
                 Software/Debug  
                 Set 
               
               
                 User 
                 Control 
                 Record 
                 Override 
                 Access 
                 Priority 
               
               
                   
               
             
            
               
                 Robot 
                 No 
                 No 
                 Yes (1) 
                 No 
                 No 
               
               
                 Local 
                 No 
                 No 
                 Yes (2) 
                 No 
                 No 
               
               
                 Caregiver 
                 Yes 
                 Yes 
                 Yes (3) 
                 No 
                 No 
               
               
                 Doctor 
                 No 
                 Yes 
                 No 
                 No 
                 No 
               
               
                 Family 
                 No 
                 No 
                 No 
                 No 
                 No 
               
               
                 Service 
                 Yes 
                 No 
                 Yes 
                 Yes 
                 Yes 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                 TABLE II 
               
             
            
               
                   
               
               
                 Requesting User  
               
            
           
           
               
               
               
               
               
               
            
               
                   
                 Local  
                 Caregiver  
                 Doctor  
                 Family  
                 Service 
               
               
                   
               
            
           
           
               
               
               
               
               
               
               
            
               
                 Current  
                 Local  
                 Not Allowed  
                 Warn current user  
                 Warn current user  
                 Warn current user  
                 Warn current user  
               
               
                 User  
                   
                   
                 of pending user  
                 of pending user  
                 of pending user  
                 of pending user  
               
               
                   
                   
                   
                 Notify requesting  
                 Notify requesting  
                 Notify requesting  
                 Notify requesting  
               
               
                   
                   
                   
                 user that system is  
                 user that system is  
                 user that system is  
                 user that system is  
               
               
                   
                   
                   
                 in use  
                 in use  
                 in use  
                 in use  
               
               
                   
                   
                   
                 Set timeout  
                 Set timeout = 5 m  
                 Set timeout = 5 m  
                 No timeout  
               
               
                   
                   
                   
                   
                   
                 Call back  
                 Call back  
               
               
                   
                 Caregiver  
                 Warn current  
                 Not Allowed  
                 Warn current user  
                 Warn current user  
                 Warn current user  
               
               
                   
                   
                 user of pending  
                   
                 of pending user  
                 of pending user  
                 of pending user  
               
               
                   
                   
                 user.  
                   
                 Notify requesting  
                 Notify requesting  
                 Notify requesting  
               
               
                   
                   
                 Notify  
                   
                 user that system is  
                 user that system is  
                 user that system is  
               
               
                   
                   
                 requesting user  
                   
                 in use  
                 in use  
                 in use  
               
               
                   
                   
                 that system is in  
                   
                 Set timeout = 5 m  
                 Set timeout = 5 m  
                 No timeout  
               
               
                   
                   
                 use.  
                   
                 Queue or callback  
                   
                 Callback  
               
               
                   
                   
                 Release control  
                   
                   
                   
                   
               
               
                   
                 Doctor  
                 Warn current  
                 Warn current user  
                 Warn current user  
                 Notify requesting  
                 Warn current user  
               
               
                   
                   
                 user of pending  
                 of pending user  
                 of pending user  
                 user that system is  
                 of pending user  
               
               
                   
                   
                 user  
                 Notify requesting  
                 Notify requesting  
                 in use  
                 Notify requesting  
               
               
                   
                   
                 Notify  
                 user that system is  
                 user that system is  
                 No timeout  
                 user that system is  
               
               
                   
                   
                 requesting user  
                 in use  
                 in use  
                 Queue or callback  
                 in use  
               
               
                   
                   
                 that system is in  
                 Set timeout = 5 m  
                 No timeout  
                   
                 No timeout  
               
               
                   
                   
                 use  
                   
                 Callback  
                   
                 Callback  
               
               
                   
                   
                 Release control  
                   
                   
                   
                   
               
               
                   
                 Family  
                 Warn current  
                 Notify requesting  
                 Warn current user  
                 Warn current user  
                 Warn current user  
               
               
                   
                   
                 user of pending  
                 user that system is  
                 of pending user  
                 of pending user  
                 of pending user  
               
               
                   
                   
                 user  
                 in use  
                 Notify requesting  
                 Notify requesting  
                 Notify requesting  
               
               
                   
                   
                 Notify  
                 No timeout  
                 user that system is  
                 user that system is  
                 user that system is  
               
               
                   
                   
                 requesting user  
                 Put in queue or  
                 in use  
                 in use  
                 in use  
               
               
                   
                   
                 that system is in  
                 callback  
                 Set timeout = 1 m  
                 Set timeout = 5 m  
                 No timeout  
               
               
                   
                   
                 use  
                   
                   
                 Queue or callback  
                 Callback  
               
               
                   
                   
                 Release  
                   
                   
                   
                   
               
               
                   
                   
                 Control  
                   
                   
                   
                   
               
               
                   
                 Service  
                 Warn current  
                 Notify requesting  
                 Warn current user  
                 Warn current user  
                 Not Allowed  
               
               
                   
                   
                 user of pending  
                 user that system is  
                 of request  
                 of pending user  
                   
               
               
                   
                   
                 user  
                 in use  
                 Notify requesting  
                 Notify requesting  
                   
               
               
                   
                   
                 Notify  
                 No timeout  
                 user that system is  
                 user that system is  
                   
               
               
                   
                   
                 requesting user  
                 Callback  
                 in use  
                 in use  
                   
               
               
                   
                   
                 that system is in  
                   
                 No timeout  
                 No timeout  
                   
               
               
                   
                   
                 use  
                   
                 Callback  
                 Queue or callback  
                   
               
               
                   
                   
                 No timeout 
               
               
                   
               
            
           
         
       
     
     The information transmitted between the station  16  and the robot  12  may be encrypted. Additionally, the user may have to enter a password to enter the system  10 . A selected robot is then given an electronic key by the station  16 . The robot  12  validates the key and returns another key to the station  16 . The keys are used to encrypt information transmitted in the session. 
     The robot  12  and remote station  16  transmit commands through the broadband network  18 . The commands can be generated by the user in a variety of ways. For example, commands to move the robot may be generated by moving the joystick  32  (see  FIG. 1 ). Table III provides a list of control commands that are generated at the remote station and transmitted to the robot through the network. 
     
       
         
           
               
             
               
                 TABLE III 
               
             
            
               
                   
               
               
                 Control Commands 
               
            
           
           
               
               
               
            
               
                 Command 
                 Example 
                 Description 
               
               
                   
               
               
                 drive 
                 drive 10.0 0.0 5.0 
                 The drive command directs the  
               
               
                   
                   
                 robot to move at the specified  
               
               
                   
                   
                 velocity (in cm/sec) in the (x,  
               
               
                   
                   
                 y) plane, and turn its facing at 
               
               
                   
                   
                 the specified rate  
               
               
                   
                   
                 (degrees/sec). 
               
               
                 goodbye 
                 goodbye 
                 The goodbye command  
               
               
                   
                   
                 terminates a user session and 
               
               
                   
                   
                 relinquishes control of the  
               
               
                   
                   
                 robot 
               
               
                 gotoHomePosition 
                 gotoHomePosition  
                 The gotoHomePosition  
               
               
                   
                 1 
                 command moves the head to a 
               
               
                   
                   
                 fixed “home” position (pan  
               
               
                   
                   
                 and tilt), and restores zoom to 
               
               
                   
                   
                 default value. The index value  
               
               
                   
                   
                 can be 0, 1, or 2. The exact 
               
               
                   
                   
                 pan/tilt values for each index  
               
               
                   
                   
                 are specified in robot 
               
               
                   
                   
                 configuration files. 
               
               
                 head 
                 head vel pan 5.0  
                 The head command controls  
               
               
                   
                 tilt 10.0 
                 the head motion. It can send 
               
               
                   
                   
                 commands in two modes,  
               
               
                   
                   
                 identified by keyword: either 
               
               
                   
                   
                 positional (“pos”) or velocity  
               
               
                   
                   
                 (“vol”). In velocity mode, the 
               
               
                   
                   
                 pan and tilt values are desired  
               
               
                   
                   
                 velocities of the head on the 
               
               
                   
                   
                 pan and tilt axes, in degree/sec. 
               
               
                   
                   
                 A single command can 
               
               
                   
                   
                 include just the pan section, or  
               
               
                   
                   
                 just the tilt section, or both. 
               
               
                 keepalive 
                 keepalive 
                 The keepalive command  
               
               
                   
                   
                 causes no action, but keeps the 
               
               
                   
                   
                 communication (socket) link  
               
               
                   
                   
                 open so that a session can 
               
               
                   
                   
                 continue. In scripts, it can be  
               
               
                   
                   
                 used to introduce delay time 
               
               
                   
                   
                 into the action. 
               
               
                 odometry 
                 odometry 5 
                 The odometry command  
               
               
                   
                   
                 enables the flow of odometry 
               
               
                   
                   
                 messages from the robot. The  
               
               
                   
                   
                 argument is the number of 
               
               
                   
                   
                 times odometry is to be  
               
               
                   
                   
                 reported each second. A value  
               
               
                   
                   
                 of 0 turns odometry off. 
               
               
                 reboot 
                 reboot 
                 The reboot command causes  
               
               
                   
                   
                 the robot computer to reboot 
               
               
                   
                   
                 immediately. The ongoing  
               
               
                   
                   
                 session is immediately broken 
               
               
                   
                   
                 off. 
               
               
                 restoreHeadPosition 
                 restoreHeadPosition 
                 The restoreHeadPosition  
               
               
                   
                   
                 functions like the 
               
               
                   
                   
                 gotoHomePosition command,  
               
               
                   
                   
                 but it homes the head to a 
               
               
                   
                   
                 position previously saved with  
               
               
                   
                   
                 gotoHomePosition. 
               
               
                 saveHeadPosition 
                 saveHeadPosition 
                 The saveHeadPosition  
               
               
                   
                   
                 command causes the robot to 
               
               
                   
                   
                 save the current head position  
               
               
                   
                   
                 (pan and tilt) in a scratch  
               
               
                   
                   
                 location in temporary storage  
               
               
                   
                   
                 so that this position can be  
               
               
                   
                   
                 restored. Subsequent calls to  
               
               
                   
                   
                 “restoreHeadPosition” will  
               
               
                   
                   
                 restore this saved position.  
               
               
                   
                   
                 Each call to saveHeadPosition  
               
               
                   
                   
                 overwrites any previously  
               
               
                   
                   
                 saved position. 
               
               
                 setCameraFocus 
                 setCameraFocus  
                 The setCameraFocus  
               
               
                   
                 100.0 
                 command controls focus for  
               
               
                   
                   
                 the camera on the robot side.  
               
               
                   
                   
                 The value sent is passed “raw” 
               
               
                   
                   
                 to the video application  
               
               
                   
                   
                 running on the robot, which 
               
               
                   
                   
                 interprets it according to its  
               
               
                   
                   
                 own specification. 
               
               
                 setCameraZoom 
                 setCameraZoom  
                 The setCameraZoom command  
               
               
                   
                 100.0 
                 controls zoom for the camera  
               
               
                   
                   
                 on the robot side. The value  
               
               
                   
                   
                 sent is passed “raw” to the  
               
               
                   
                   
                 video application running on  
               
               
                   
                   
                 the robot, which interprets it  
               
               
                   
                   
                 according to its own  
               
               
                   
                   
                 specification. 
               
               
                 shutdown 
                 Shutdown 
                 The shutdown command shuts  
               
               
                   
                   
                 down the robot and powers 
               
               
                   
                   
                 down its computer. 
               
               
                 stop 
                 stop 
                 The stop command directs the  
               
               
                   
                   
                 robot to stop moving 
               
               
                   
                   
                 immediately. It is assumed this 
               
               
                   
                   
                 will be as sudden a stop as 
               
               
                   
                   
                 the mechanism can safely  
               
               
                   
                   
                 accommodate. 
               
               
                 timing 
                 Timing 3245629  
                 The timing message is used to  
               
               
                   
                 500 
                 estimate message latency. 
               
               
                   
                   
                 It holds the UCT value  
               
               
                   
                   
                 (seconds + milliseconds) of the  
               
               
                   
                   
                 time the message was sent, as  
               
               
                   
                   
                 recorded on the sending 
               
               
                   
                   
                 machine. To do a valid test, 
               
               
                   
                   
                 you must compare results in 
               
               
                   
                   
                 each direction (i.e., sending  
               
               
                   
                   
                 from machine A to machine B, 
               
               
                   
                   
                 then from machine B to  
               
               
                   
                   
                 machine A) in order to account  
               
               
                   
                   
                 for differences in the clocks  
               
               
                   
                   
                 between the two machines.  
               
               
                   
                   
                 The robot records data  
               
               
                   
                   
                 internally to estimate average  
               
               
                   
                   
                 and maximum latency over the  
               
               
                   
                   
                 course of a session, which it 
               
               
                   
                   
                 prints to log files. 
               
               
                 userTask 
                 userTask “Jane  
                 The userTask command  
               
               
                   
                 Doe” “Remote  
                 notifies the robot of the current 
               
               
                   
                 Visit” 
                 user and task. It typically is  
               
               
                   
                   
                 sent once at the start of the 
               
               
                   
                   
                 session, although it can be sent  
               
               
                   
                   
                 during a session if the user 
               
               
                   
                   
                 and/or task change. The robot  
               
               
                   
                   
                 uses this information for 
               
               
                   
                   
                 record-keeping. 
               
               
                   
               
            
           
         
       
     
     Table IV provides a list of reporting commands that are generated by the robot and transmitted to the remote station through the network. 
     
       
         
           
               
             
               
                 TABLE IV 
               
             
            
               
                   
               
               
                 Reporting Commands 
               
            
           
           
               
               
               
            
               
                 Command 
                 Example 
                 Description 
               
               
                   
               
               
                 abnormalExit 
                 abnormalExit 
                 This message informs the  
               
               
                   
                   
                 user that the robot software  
               
               
                   
                   
                 has crashed or otherwise  
               
               
                   
                   
                 exited abnormally. Te robot  
               
               
                   
                   
                 software catches top-level  
               
               
                   
                   
                 exceptions and generates this 
               
               
                   
                   
                 message if any such  
               
               
                   
                   
                 exceptions occur. 
               
               
                 bodyType 
                 bodyType 3 
                 The bodyType message  
               
               
                   
                   
                 informs the station which  
               
               
                   
                   
                 type body (using the  
               
               
                   
                   
                 numbering of the mechanical 
               
               
                   
                   
                 team) the current robot has.  
               
               
                   
                   
                 This allows the robot to be  
               
               
                   
                   
                 drawn correctly in the station  
               
               
                   
                   
                 user interface, and allows for 
               
               
                   
                   
                 any other necessary body- 
               
               
                   
                   
                 specific adjustments. 
               
               
                 driveEnabled 
                 driveEnabled true 
                 This message is sent at the  
               
               
                   
                   
                 start of a session to indicate 
               
               
                   
                   
                 whether the drive system is  
               
               
                   
                   
                 operational. 
               
               
                 emergencyShutdown 
                 emergencyShutdown 
                 This message informs the  
               
               
                   
                   
                 station that the robot software 
               
               
                   
                   
                 has detected a possible  
               
               
                   
                   
                 “runaway” condition (an  
               
               
                   
                   
                 failure causing the robot to  
               
               
                   
                   
                 move out of control) and is  
               
               
                   
                   
                 shutting the entire system  
               
               
                   
                   
                 down to prevent hazardous  
               
               
                   
                   
                 motion. 
               
               
                 odometry 
                 odometry 10 20 340 
                 The odometry command  
               
               
                   
                   
                 reports the current (x, y) 
               
               
                   
                   
                 position (cm) and body  
               
               
                   
                   
                 orientation (degrees) of the  
               
               
                   
                   
                 robot, in the original  
               
               
                   
                   
                 coordinate space of the robot  
               
               
                   
                   
                 at the start of the session. 
               
               
                 sensorGroup 
                 group_data 
                 Sensors on the robot are  
               
               
                   
                   
                 arranged into groups, each  
               
               
                   
                   
                 group of a single type  
               
               
                   
                   
                 (bumps, range sensors,  
               
               
                   
                   
                 charge meter, etc.) The  
               
               
                   
                   
                 sensorGroup message is sent  
               
               
                   
                   
                 once per group at the start of  
               
               
                   
                   
                 each session. It contains the 
               
               
                   
                   
                 number, type, locations, and 
               
               
                   
                   
                 any other relevant data for  
               
               
                   
                   
                 the sensors in that group. The  
               
               
                   
                   
                 station assumes nothing  
               
               
                   
                   
                 about the equipment carried  
               
               
                   
                   
                 on the robot; everything it  
               
               
                   
                   
                 knows about the sensors  
               
               
                   
                   
                 comes from the sensorGroup 
               
               
                   
                   
                 messages. 
               
               
                 sensorState 
                 groupName state  
                 The sensorState command  
               
               
                   
                 data 
                 reports the current state  
               
               
                   
                   
                 values for a specified group  
               
               
                   
                   
                 of sensor. The syntax and 
               
               
                   
                   
                 interpretation for the state  
               
               
                   
                   
                 data is specific to each group. 
               
               
                   
                   
                 This message is sent once for  
               
               
                   
                   
                 each group at each sensor 
               
               
                   
                   
                 evaluation (normally several  
               
               
                   
                   
                 times per second). 
               
               
                 systemError 
                 systemError  
                 This message informs the  
               
               
                   
                 driveController 
                 station user of a failure in one  
               
               
                   
                   
                 of the robot&#39;s subsystems.  
               
               
                   
                   
                 The error_type argument  
               
               
                   
                   
                 indicates which subsystem  
               
               
                   
                   
                 failed, including  
               
               
                   
                   
                 driveController,  
               
               
                   
                   
                 sensorController, headHome. 
               
               
                 systemlnfo 
                 systemlnfo wireless  
                 This message allows regular  
               
               
                   
                 45 
                 reporting of information that 
               
               
                   
                   
                 falls outside the sensor  
               
               
                   
                   
                 system such as wireless  
               
               
                   
                   
                 signal strength. 
               
               
                 text 
                 text “This is  
                 The text string sends a text  
               
               
                   
                 some text” 
                 string from the robot to the 
               
               
                   
                   
                 station, where the string is  
               
               
                   
                   
                 displayed to the user. This 
               
               
                   
                   
                 message is used mainly for  
               
               
                   
                   
                 debugging. 
               
               
                 version 
                 version 1.6 
                 This message identifies the  
               
               
                   
                   
                 software version currently 
               
               
                   
                   
                 running on the robot. It is  
               
               
                   
                   
                 sent once at the start of the 
               
               
                   
                   
                 session to allow the station to  
               
               
                   
                   
                 do any necessary backward 
               
               
                   
                   
                 compatibility adjustments. 
               
               
                   
               
            
           
         
       
     
     The processor  154  of the robot high level controller  150  may operate a program that determines whether the robot  12  has received a robot control command within a time interval. For example, if the robot  12  does not receive a control command within 2 seconds then the processor  154  provides instructions to the low level controller  150  to stop the robot  12 . Although a software embodiment is described, it is to be understood that the control command monitoring feature could be implemented with hardware, or a combination of hardware and software. The hardware may include a timer that is reset each time a control command is received and generates, or terminates, a command or signal, to stop the robot. 
     The remote station computer  22  may monitor the receipt of video images provided by the robot camera. The computer  22  may generate and transmit a STOP command to the robot if the remote station does not receive or transmit an updated video image within a time interval. The STOP command causes the robot to stop. By way of example, the computer  22  may generate a STOP command if the remote control station does not receive a new video image within 2 seconds. Although a software embodiment is described, it is to be understood that the video image monitoring feature could be implemented with hardware, or a combination of hardware and software. The hardware may include a timer that is reset each time a new video image is received and generates, or terminates, a command or signal, to generate the robot STOP command. 
     The robot may also have internal safety failure features. For example, the robot may monitor communication between the robot controller and the robot servo used to operate the platform motors. The robot monitor may switch a relay to terminate power to the platform motors if the monitor detects a lack of communication between the robot controller and the motor servo. 
     The remote station may also have a safety feature for the input device  32 . For example, if there is no input from the joystick for a certain time interval (e.g. 10 seconds) the computer  22  may not relay subsequent input unless the user presses a button for another time interval (e.g. 2 seconds), which reactivates the input device. 
       FIG. 7  shows another embodiment of the robot as a robot head  350  that can both pivot and spin the camera  38  and the monitor  40 . The robot head  350  can be similar to the robot  12  but without the platform  250 . The robot head  350  may have actuators  352  and linkages  354  to pivot the camera  38  and monitor  40  about a pivot axis  4 , and spin the camera  38  and monitor  40  about a spin axis  5 . The pivot axis may intersect the spin axis. Having a robot head  350  that both pivots and spins provides a wide viewing area. The robot head  350  may be in the system either with or instead of the mobile robot  12 . The robot head can be particularly useful for doctor proctoring. The head can be located at a medical facility such as an emergency room or a doctor&#39;s office. A doctor at the remote location can assist in the diagnosis and medical treatment of a patient located at the robot location. The doctor can move the head to view the patient through control commands from the remote control station. Doctor proctoring can also be performed with a mobile robot  12 . 
     While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative of and not restrictive on the broad invention, and that this invention not be limited to the specific constructions and arrangements shown and described, since various other modifications may occur to those ordinarily skilled in the art.