Abstract:
An apparatus provides selective communication between multiple programmable robot controllers and one or more teaching devices connected by a network. The network controls communication between the teaching devices and the controllers including active tasks and passive tasks for preventing communication of active tasks between any of the controllers and more than one of any of the teaching devices. The network permits communication of the passive tasks between any of the controllers and one of the teaching devices communicating active tasks with another one of the controllers.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. provisional patent application Ser. No. 60/658,476 filed Mar. 4, 2005. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to a flexible connection of teaching devices to programmable controllers. A network is used for selectively connecting one teaching device to two or more controllers, or selecting one of at least two teaching devices for connection to selected ones of a plurality of controllers. 
         [0003]    Generally, one teaching pendant is hard wired to one programmable controller. If it is desired to communicate with a second programmable controller, then the teaching pendant is manually disconnected from the first programmable controller, or robot, for manual connection to the second controller, or robot. 
         [0004]    The prior art requires a teach pendant to be connected to a robot controller at all times and is generally dedicated to the control of that one programmable robot controller. In some cases multiple robots are connected to the same controller in which case one pendant can control multiple robots. However, this is limited to the number of robots that a single controller can accept. It is also limited in that it is difficult or impossible for the robot manufacturer to configure inventory to meet the needs of any combination or permutation of robot arms and controllers. 
         [0005]    Another shortcoming of the prior art is that there is only ever one teach pendant that can be used. 
         [0006]    The present invention is aimed at one or more of the problems identified above. 
       SUMMARY OF THE INVENTION 
       [0007]    In one aspect of the invention, a robot system is provided with a single teach pendant for communicating with multiple programmable controllers or multiple robots controlled by a single programmable controller. This is especially advantageous in a situation where one controller controls multiple robots, such as a dual arm system, allowing the teaching pendant to select either robot. However, in this case there is only one controller involved. 
         [0008]    In another aspect of the invention, a system is provided for multiple teaching devices to communicate with multiple programmable controllers. When a teaching device is communicating with a programmable controller, the teaching device can also communicate with other programmable controls to perform non-motion functions. Therefore, a teaching device can log into the robot controller from a PC and do operations that don&#39;t specifically relate to jogging or teaching points. This is unique in that the pendant can do all operations just like a dedicated pendant once it is logged in, providing a single interface for multiple controllers. 
         [0009]    The shortcomings of the prior art systems are avoided by allowing the pendant to make connection via a network (Ethernet, wireless, any such connection) to any robot controller that is designated to be part of the overall system. This allows a system to be configured with multiple robot controllers and one or multiple pendants. In such a system any pendant can connect to and operate any controller. With this approach as many teach pendants as are required at a given time to do teaching operations can be provided. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0010]    The above, as well as other, advantages of the present invention will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment when considered in the light of the accompanying drawings in which: 
           [0011]      FIG. 1  is a schematic block diagram of a system in accordance with the present invention utilizing one teach pendant; 
           [0012]      FIG. 2  is a schematic block diagram of a system in accordance with the present invention utilizing two teach pendants; 
           [0013]      FIG. 3  is the block diagram of  FIG. 2  showing one combination of connections between the teach pendants and the controllers according to the present invention; 
           [0014]      FIG. 4  is an example of a user display for selecting a programmable controller on a teach pendant of the present invention; and 
           [0015]      FIG. 5  is an example of a user display illustrating multiple controllers available for remote log in on a teach pendant of the present invention. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0016]    U.S. provisional patent application Ser. No. 60/658,476 filed Mar. 4, 2005 is hereby incorporated herein by reference. 
         [0017]      FIG. 1  shows a system  10  according to the present invention having a single teaching device such as a teach pendant  11  connected to a network  12  (Ethernet, wireless, any such connection). A plurality of programmable controllers are also connected to the network  12  such as a controller # 1   13 , a controller # 2   14  and a controller # 3   15 . Three controllers are shown by way of example, however, as little as two, or more than three controllers can be utilized. The system  10  permits the teach pendant  11  to be selectively connected to one or more of the controllers  13 ,  14  and  15  through the network  12 . 
         [0018]    The single teach pendant  11  is coupled to one of the robot controllers, for example the controller  13 , preferably by logging in to the controller  13  via the network  12  for actively performing a variety of tasks such as jogging, running and displaying programs. While logged in to the controller  13 , the pendant  11  may remotely log in to a second controller, e.g. the controller  14 , for passive tasks such as monitoring operations. The pendant  11  displays both operating menus for each of the controllers  13 ,  14  while in dual communication. 
         [0019]    Additionally, the single teach pendant  11  may remotely log in to a third controller, the controller  15 , for passive tasks while displaying the operating menu for each of the controllers  13 ,  14 , and  15 . The single teach pendant  11  may remotely log in to any number of controllers for performing passive tasks and display the corresponding operating menu for each controller connected. The teach pendant  11  can be of the type described in U.S. Pat. No. 6,560, 513, entitled Robotic System with Teach Pendant” issued May 6, 2003, incorporated herein by reference. 
         [0020]      FIG. 2  shows a system  20  according to the present invention that incorporates all of the components of the system  10  and adds a second teaching device such as a teach pendant  21  connected to the network  12 . The system  20  permits the pendant  21  to be selectively connected to one or more of the controllers  13 ,  14  and  15  through the network  12  while protecting against simultaneous connection of the pendants  11  and  21  to each of the controllers  13 ,  14  and  15  through the network  12 . The system according to the present invention can selectively connect each of a plurality of teach pendants to each of a plurality of programmable controllers. 
         [0021]    In this embodiment, each of the multiple teach pendants  11 ,  21  is logged in to the individual controllers  13 ,  14  respectively and may remotely log in to the other controller and/or the additional controller  15  for performing passive tasks. Each teach pendant  11 ,  21  may remotely log in to any number of controllers for performing passive tasks and display the corresponding operating menu for each controller connected. 
         [0022]    The remotely logged in teach pendant  11 ,  21  is capable of, but not limited to, inputting the following directives:
       request web pages from the remote robot,   start/stop monitors on the remote robot,   input keys and commands to the remote robot,   input watchdog characters and sequence numbers to the remote robot,   start a RPC connection to the remote robot and get/set data, and   keep the RPC connection to the master robot.       
 
         [0029]    And is capable of, but not limited to, directing the remote robot to output and display of following directives:
       The remote robot will send web pages to the pendant, and   The remote robot will send PMON packets to the pendant.       
 
         [0032]    With reference to  FIG. 3 , the network  12  can include a server that runs a program that prevents the simultaneous connection of the teach pendant  11  and the teach pendant  21  to the same controller for performing active tasks. The network  12  has an active tasks portion  22  and a passive tasks portion  23  for the teach pendant  11  and has an active tasks portion  24  and a passive tasks portion  25  for the teach pendant  21 . For example, assume that the teach pendant  11  is connected to the controller  13  for active tasks through the active tasks portion  22  as shown in  FIG. 3 . Then the active tasks portion  24  will prevent connection of the teach pendant  21  to the controller  13  for active tasks, but does permit connection of the teach pendant  21  to the controllers  14  and  15  for active tasks as shown in  FIG. 3 . In a similar manner, the teach pendant  11  is connected to the controller  13  through the passive tasks portion  23  and the teach pendant  21  is connected to the controllers  14  and  15  for passive tasks through the passive tasks portion  25 . However, it may be important that the user of either of the teach pendants to know how a controller connected to the other teach pendant is operating. Thus, the server in the network  12  can permit connection of the teach pendant  11  to the controllers  14  and  15  through the passive tasks portion  23  and connection of the teach pendant  21  to the controller  13  through the passive tasks portion  25 . 
         [0033]    Not shown are the typical emergency stop switch and deadman switch which are needed to secure the safety of an operator. In a preferred embodiment, the emergency stops of the multiple teaching devices are interlocked through hardware circuits to stop all robots when one emergency stop is activated. 
         [0034]    The teach pendant  11 ,  21  also includes a teach pendant control module (not shown) which provides communication with each of the controllers  13 ,  14  and  15  including visual and audio feedback to the operator and means for and inputting receiving data.  FIGS. 4 and 5  illustrate displays that are generated at the teach pendant allowing the operator to choose between a series of multiple individual log in&#39;s ( FIG. 4 ) and a multiple display, such as a list and corresponding picture, for the log in&#39;s ( FIG. 5 ). To aid the operator during communication, each programmable controller may be assigned unique names and/or colors on the pendant display indicating whether or not a connection is made and what type of connection, direct or remote. This display may be a user designed web page or direct link. If a direct log in connection between the robot and the teaching device is lost, the robot will stop and the display on the teaching device will indicate the disconnection. Alternatively, if the programmable controller of the designated robot is shut down or removed, the teaching device will connect to a default programmable controller and display this connection. For example, if the controller  14  is a default controller and the controller  13  is shut down, the network  12  will substitute the controller  14  for communication of active tasks with the teach pendant  11 . 
         [0035]    As shown in  FIG. 4 , the teach pendant  11 ,  21  has a display  30  including a central screen  31  for generating a visual display of an icon  32  identifying the robot to which the teach pendant is connected. An instruction above the icon  32  directs the user to press ENTER to change the display to a different robot to be selected. As shown in  FIG. 5 , the central screen  31  has multiple icons  32  through  35  each representing a different robot to be selected. 
         [0036]    As with the emergency stops, the networking of the multiple programmer controllers with the multiple teaching devices allows the robot system to notify all connected devices, including remote PC&#39;s, input devices, and processors, certain operating directives. These operating directives can include: 1) that only a teaching device can activate programs and only at a safe speed; 2) that only a teaching device can activate programs and may be doing so at full program speed; or 3) that all teaching devices are disabled and devices other than a teaching device can activate programs. Each teaching pendant displays such notifications. 
         [0037]    In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.