Different positions in 2 robots with same TP program

    Hello you all,


    I recently received a new P50iB Fanuc robot in my coating line. This new Robot cell is a "clone" of the first one I had installed, a replica of the first coating line. Same dimensions, same parameters, same supplier, same tool offset, same all.


    What we did after installation is that all coating routines (TP programs) were copied from Robot 1 to Robot 2, but unfortunately the robot position in each point of the programs is not the same between robots. This is creating coating defects because of not following the original points the program was intended to follow.


    I have several questions and I hope you can help me:


    1. Why do you think this happens? There should be a logical explanation for this.


    2. Is there any solution for this? If not I will have to make a coating routine for the same product twice (the should be coated in both coating lines)

  • Jump to the most helpful post

    Quote from Sergei Troizky

    To what extend "This new Robot cell is a "clone" of the first one?"

    Did you copy sysvars.sv file from the first one?

    A "clone" in terms of: the same company built the coating line with the same drawings of the first one (two years apart).

    They have equal dimensions, equal distribution, equal robot mount, equal AHUs, equal conveyor, equal sensors, etc. They even share the fixtures for the products.


    Regarding the copy of sysvars.sv I would need to check with the integrator, but I dont think so (is there any way to know at this point?). The only things I copied were the TP programs that I created in robot 1 for coating the different products.

    Are the machines physically identical? Even a small change in the mounting position of the robot can make a difference and its obvious they did not teach a proper user and tool frame so all bets are off.

    Quote from HawkME

    Are the machines phiscally identical? Even a small change in the mounting position of the robot can make a difference and its obvious the did not teach a proper user and tool frame so all bets are off.

    Yes they are phisically identical, at least theoretically. The even share the curing conveyor, after coating another robot transfers the pieces from the coating line to the curing line.

    How far off are they? Can you take the robots to the same real world position, maybe with the paint nozzle at the corner of a frame. Then compare positions on the position screen. Make sure orientation is the same when doing this test.

    Quote from HawkME

    How far off are they? Can you take the robots to the same real world position, maybe with the paint nozzle at the corner of a frame. Then compare positions on the position screen. Make sure orientation is the same when doing this test.

    I will try this during the weekend, right now the coating line is in series production. What I did as containment action was to run the program in Robot 1 then mark the piece in a point with a reference and then compare that same point in Robot 2, after that I made a program shift until the 2 positions were "the same".


    The program shift that helped me was X: -20.00; Y: -35:00; Z: -5.00; in milimeters.


    I'm sorry for the ignorance but how would I know I'm at the corner of the frame?

    • Helpful

    I just meant the corner of the machine frame or any physical corner easy to line up with.


    It looks like your off by about 1.5". That could easily be a difference in the tool frame or user frame caused by a real physical difference.


    You would have to take some measurements to find out what's different, either the tool or the relationship of the robot base to the part you are painting. Then correct in the tool or user frame.


    If the system was setup with a proper user and tool frame this wouldn't happen. Unfortunately most programmers neglect this step.

    I really appreciate your replies, I will make manual measurements of this during the weekend and I hope I can find a physical difference and then adjust the frames.


    I will reply as soon as I find out anything relevant!

    Hi again HawkME!


    I tried to find any physical dimensions that were different, and everything is the same, I mean with some slight tolerance, but the same. Distance from Axis 6 to paint gun is the same, orientation, home position, etc.


    I tried to make some changes and a new quesiton comes up, both robots when I'm in jogging mode they move the same in X, Y & Z. But when I make an offset in X it really moves in Y and viceversa... How come?

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