Move robot in auto mode with fence open

    Hi!

    Is it possible to move the robot in AUTO mode with the fence (door) open? Without any hardware, wiring modification.

    To understand the conditions. We are building a laser cutter with a fanuc robot. The cell is not transparent. The robot can only move in auto mode when the cell's door is closed.

    We are using it now in T1 with the teach pendant.

    I am writing a custom HMI interface that can be accessed from a PC. I have a button that starts a selected program. Right now I am using a karel code to set F[1] flag to ON. The MACRO option uses this signal to run the program. The problem is that MACRO only works in AUTO mode.

    I want a "TEST program" with laser OFF to simulate the movement for the cut. So for it I want to

    • move the robot
    • without teach pendant
    • with door open

    Then if the move path is correct I can close the door and start cutting.

  • Go to Best Answer

    1) Is it possible to move the robot in AUTO mode with the fence (door) open? Without any hardware, wiring modification.

    The robot is an entity, directed by the programmer. The robot doesn't the surrounds until you teach them. The robot doesn't know it is inside a cell with a laser cutting tool. So, the answer to your question is YES, you can RUN a program when the robot is in auto mode with the door open. I bet you, 90% or more of the robot programmers do when they are testing the program , but also ( I hope) they are by themselves with the perimeter of the cell of the cell close and with the E-stop on their hands. You can stand OUTSIDE the robot reach safely


    2)The problem is that MACRO only works in AUTO mode.

    Can you show us the macro ? Why ca not run in manual ?


    3)I want a "TEST program" with laser OFF to simulate the movement for the cut. So for it I want to

    • move the robot
    • without teach pendant
    • with door open

    Then if the move path is correct I can close the door and start cutting.


    STEP 1

    counter = zero

    label a

    you are holding the pendant on teach mode. Door open

    You program the path and run in manual, then you touch up points

    If counter is less than 1 million jump to label a


    Once the motions, etc , are inserted on your brain do

    STEP 2

    label b

    you are holding the pendant in auto mode, no tool active, Door open

    You program the path and run in manual, then you touch up points

    If counter is less than 1 million jump to label b

    STEP 3

    This is why we get pay good money

    Repeat step 3 but turn the laser on and off gradually (in sectors, one at the time) Door close this time. Trust you abilities

    For example turn the laser on on the very first point, and off a couple of centimeters later, just to see how starts and the keep going

    Retired but still helping

    Do not run it in auto with the door open. :gaah: Someone will get hurt.

    Just pickup the TP in teach mode, select your program from the list and, hold Deadman shift and press the fwd button. Make sure the laser is off.

    You can run the program in T1 if you manually start it from the pendant, not using a macro start.

    Fabian Munoz

    I can't show you the macro. It's not a macro program. It's a "SETUP > MACRO" assign to a FLAG.

    for example:

    program HOME assigned to FLAG[1]. If I set FLAG[1]=ON, the HOME program starts.



    I know how to run the robot manually but the main problem is that the worker who will use the laser cutter he doesn't know anything about robots. That's why I am creating a HMI screen where you can choose the program from a list, you can set the position register using textbox, you can disable or enable the laser permission IO with a button and at the end you can start the robot program.

    It is mandatory to run the robot with a press of a button ON the HMI. Not manually, not from TP.

    The programs with the paths are generated by a computer program and it is different for each cut. The operator can't change this program. He just has to run it with a touch of a button. Still not from TP.


    HawkME

    No one can get hurt. The "door" rather a "window" where you can see the robot from a distance. You can't get close to it. It is only there to protect your eyes if you cut with the laser. But if the laser is on, there is no way you could get hurt. Also if the door is open, you can't turn on the laser.

    Just to clarify my statements.

    You said "We are building a laser cutter with a fanuc robot.".

    All my answers are based on integration not production

    Don't let a human decide on the program from a list. Put identification devices to automatically read the fixture that you are working from. Yes, you could use the operator to confirm that but never to actually select

    Retired but still helping

    Putting this simply for anybody just skimming this thread:

    DO NOT RUN THE ROBOT IN AUTO WITHOUT THE FENCE CIRCUIT ENABLED!!!!

    Not even macros and especially not as a long-term solution. Running the robot in Auto with the fence open or an incomplete fence is something we integrators/programmers try really hard to avoid even when commissioning a new piece of equipment. Trying to do it as a permanent solution for production is completely insane and I'm refraining from cussing you out merely because I assume you just didn't know/haven't learned this yet.

    If this window is actually out of reach of the robot and is properly interlocked with the laser itself, then you just need to make the physical wiring change to remove it (and only the window) from your robot fence circuit. You should also do a proper safety/risk assessment of the cell prior to and after making any changes like this.

    Edited once, last by Erik Olsen (July 28, 2022 at 8:27 PM).

    • Best Answer

    I'm guessing this "window" opens and closes, and has dual channel safety switches that activate when the window is closed, or in the safe position. I am also guessing that it was designed to provide a safety barrier from the risk of blasting your eye's out from a high power laser. Hence the window is a guard for the laser, not the robot, if in fact it is out of the reach from the robot.

    If my guesses are correct, then the solution is obvious, the window safety switches need to be tied into the safety circuit for the laser, not the robot.

    If you only have one safety circuit for the laser and the the robot, then you need to divide them.

    When a safety system is poorly designed and difficult to use, people will find a way around it. This post is an excellent example of that.

    It will be much cheaper to properly fix your safety circuit than to pay for the operator that gets crushed by the robot or shoots their eye out.

    There is actually another big problem: LASER

    Normally a laser cell should be completely shielded by a wall. Windows to look inside normally are very small and very expensive.

    Using a camera system mounted to the tool could solve the problem by having everything sealed and also see the path.

    For simulation of the movement a simulation tool would be very helpful


    So it is not possible to do this from the software side. I was just curious only about this. Thank you for your answers. I think we will change the safety circuit for this "window" to the laser only.

    FYI: There is no possible way for the robot to crush the operator or to shoot their eye out.
    There is a big cell around the robot, from this "window" you can only see it from distance. If it's open, the laser can't be turned on by safety.

    MOM

    We have a camera inside the cell right now but it's far away with a big field of view so we can see the whole robot but we can't see if it would cut into a previously cut hole.

    So to summarize, the cheapest way would be to change the safety circuit. Or to put a camera on the laser head itself.

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