Posts by Leon

    Depending on how the robot is programmed the answers differs. what type of movements are used in the program PTP, LIN ,Spline? If i would have to guess it would be LIN.

    Then the second question are you using approximate motions? like C_DIS and C_VEL. if yes which one and what are the settings $apo.CVEL and $apo.CDIS.

    Could you post a (part of) program?

    Could you specify what controller you are using? then we can give more specific answers.

    But in general there are options you can try. The simplest would be something like this in your main program:

    DEFINE BOOL Switch
    IF Switch == 1 Then
    IF Switch == 0 Then

    Depending on the switch position a different subroutine is executed

    Hi, one option you can also look if you maybe have inside your current KPC already the DSE C33 Card

    unfortunately not, this is one of the older vkrc2.

    look inside the PC if you can see some capacitors swollen on the motherboard

    Capacitors seem fine. no swelling or leaking. funnily enough i have another vkrc2 with leaking capacitors that is running just fine (for now).

    KRC4 upgrade usually means everything needs to be exchanged, even the robot needs to be exchanged.

    Yes, and i don't mind to invest to keep everything reliable and serviceable. I just find it a waste of the robot itself. Mechanically these things are still good enough for our use.

    So the last 2 days i have been having some problems with the PC in one of our KRC2 controllers. (this use to be VKRC2 but is now running normal kss 4.97). During production the screen freezes or turns black. after a cold start everything seems to be fine again. 2 weeks ago i had a similar problem only then the freezing of the screen was temporary and i got this error: "KRC systemfault 14 tZYK"

    For now it only seems to happen after the robot is booted up in the morning. Within the first hour or something like that. After that no more issues

    I have already contacted kuka service about this and they suspect that the motherboard of the PC is showing its age. I agree with this diagnosis, but now come the problem. normally we would just have kuka swap out the PC and everything would be fine. But because kuka is now down to its last KRC2 PC's (of this type) they have gotten a lot more expensive (€6900).

    I see a few options:

    • Pay up and continue working (we are a production company after all)
    • Upgrade the PC to that off a KRC2 edition 05 (still old but at least it is running windows XP instead of 95). For a edtion 05 there are more parts available (for now)
    • Upgrade to KRC4. probably the best option for the long term, and the most expensive option.

    For now i am going to leave the controller powered on in the evenings. if the problem only occurs in a small window after booting, then i am going to make sure that i don't need to boot up the PC. if that works that would be a tempory fix, but i hopefully buy some extra time to figure out what the best way forward is. or better said what our budget allows.

    Am I right in thinking the higher the payload the more rigid the robot?

    Not necessarily, a heavier robot has the same rigidty problems as a small one (especially if you are using used ones). The mass of the robot it self does give some advantages as it works as a kind of damper.

    I myself use KR150 and KR210's for milling LLDPE (soft plastic) and there i can sometimes still see the effect of the low rigidity of the arm in the start of a cut.

    i also see no problem in milling polystyrene, but wood might become a problem. Don't forget that with the 30kg of payload that is available that needs to be divided in to your spindle + tool and the forces that you get from the milling itself.

    Well lets start with the basics. which control are you using. preferably with the software version. This is clearly stated in the topic "Read first".

    Have you correctly calibrated your tool?

    If you have then you can continue with base calibration. Measuring a base works best on a big surface. you start with x,y zero. then move to a positive point on the x-axis (as far as you can from zero). and last move to a positive point in the X/y plane. Again the further from zero the better.

    to check if tool and base are calibrated correctly, you can manually select them and then jog over the surface. Your tool TCP (tool center point) should move parallel to the surface when jogging in x and y.

    In your program check if you have the right tool and base selected.

    Another thing to consider is that with a cnc machines it is relatively simple to go from a calculated toolpath to a accurate cut product. With robots this is a lot more difficult. Robot base and tool must be calibrate perfectly to get an reasonably accurate cut.

    Robots are a lot less stiff and you will notice that.

    I have looked in to getting CAM software for our robots a few times and each time i come to the same conclusion: To expensive! (for us)

    I have gone for a different approach. Most of the product i have to cut need relatively simple work. a circle hole here, a slotted hole there. stuff like that. So i made some default functions to do just that. so in code you get simple commands like: cut_circle(60,6) which means cut a circle 60mm in diameter 6mm deep.

    I do get more complicated work now and then, but i can calculate those tool paths by hand. it is bit tedious but certainly not impossible. As long as i don't have to do that each week i am not buying cam software.

    SPS should always be running, but if i read your post correctly you assume that because the SPS is stopped that the main robot program also should be stopped and it is not?

    The SPS and the Main motion program are 2 completely different things and they can run independently of each other. So you can start the main program with the SPS stopped.

    What you are describing is impossible, the speed override on the KCP always changes the speed of the robot. it is kind of in the name "override".

    There are other ways to achieve what you are after, but that would require some more programming knowledge. you can find most of it in the "expert programming manual".7

    First, don't use the inline forms for your motions. if you program the motions yourself you can set speed once at the beginning with $vel.cp = paint_speed. instead of setting speed in each point.

    The variable paint_speed could then be changed when it is needed and in different ways depending on the controller and software that you are using.

    What is your goal? or better what are you trying to improve with this "system" because if you need real time control, then RSI is your only option. If it does not need to be real time, then what is the problem with writing different (motion) programs and calling them from a PLC (or something else).

    If you can formulate a bit better why you need this, it would make it a lot easier to point you in the right direction.

    First question: was this robot working before in automatic?

    Second: The error points to the device-net communication, it could be that a driver reset is necessary tot get it working again. But that is only if it was working before and somebody hasn't been messing with the device net configuration.

    Third: when you switch to automatic, can you turn on the drives? and then start is not working? or can you not start the drives also?

    Restore from an old back-up. If you don't have that you can reinstall Windows and kss if you have the software CD's (or if they are on the back-up drive.)

    If you dont have any of that. then your only option is to ask kuka. you can not ask for software here.

    From now on ill only ask you guys.

    Not a bad idea, but i would advise to ask kuka first. especially about stuff like this. asking costs nothing and in my experience they are always willing to give information if you ask.

    This forum has a lot of information and experienced people on it, but it is no replacement for kuka service.