Kuka KR6 Program override to 5% with input

    Hi,


    We have Kuka KR6 R900 sixx robot here with KRC4 compact controller. I am adding SICK S30B laser safety scanner and I have defined a warning zone(outer zone) and an alarm zone(inner zone). Inner warning zone is working like it should and stops robot when zone is entered(by safety inputs). But I would like following functionality when warning zone is entered:


    1. When someone enters warning zone robot program override should go to 5%
    2. When warning zone is left override should return to previous value.


    How can achieve this functionality with this controller? I do not want errors or stops when this warning zone is broken only robot to slow down. We have SafeOperation option 3.2 installed also if that is needed.


    Tero

    Though I have not tried exactly as you asked and not used SICK S30B before,
    but what comes to mind is the the variable $SR_OV_RED (Reduction factor of SafeRobot override control to speed limits 10-95 % in custom.dat which can be set in a real time in SPS.SUB to control the speed of the robot with a conditional statement as desired. Note that the $SR_VEL_RED must be set to true in this case. The problem here is, as default, the minimum is 10%


    But if 5% is necessary you could also use $OV_PRO in sps.sub instead.

    The SPS is NOT safety-qualified. If this speed reduction is being used for the safety of humans operating near the robot, then the SPS cannot be part of the solution. Only SafeOperation inputs, zones, and limits are legal for this.

    Quote from SkyeFire


    The SPS is NOT safety-qualified. If this speed reduction is being used for the safety of humans operating near the robot, then the SPS cannot be part of the solution. Only SafeOperation inputs, zones, and limits are legal for this.


    Thank you for this SkyeFire, I concentrated on answering question related to override with input in real-time, but did not see that the override has to do with "someone" entering the working area of robot. Only SafeOperation is legal in this case.

    Hi,


    Ok. We are going to define warning zone so far away that it does not need to be "legal". We will use alert zone as legal function and it will be defined further than robot reaches with tools. Do I understand correctly:


    1. We set $SR_OV_RED = 95 (in custom.dat)
    2. We set $SR_VEL_RED = TRUE (in custom.dat)
    3. We connect warning field1 output to one of robot inputs
    4. Then we modify value of $SR_OV_RED = 10 when input for warning field 1 is triggered
    5. After input is false we set $SR_OV_RED = 95 again


    Would this kind of program do:


    Def PLC()
    loop
    USER PLC
    if $in[10] = = true then
    $SR_OV_RED = 10
    else
    $SR_OV_RED = 95
    endif
    endloop
    end


    Kuka is new to me I have been working with Kawasaki robots earlier. So try to bare with me :icon_wink:


    Tero

    Edited once, last by terok ().

    It still won't be "legal", because that code can be easily modified or disabled without any sort of traceability.


    Also, I dont' know offhand if the $SR_ values can be modified "on the fly," but I strongly doubt it. The values are intended to be set once, then only switched on/off by the safety-qualified inputs coming from your safety circuit.

    Hi,



    You missed my point a little bit. This Warning zone that slows down robot is not even needed it is so far away from robots cell area(out of robots reach). It can be disabled or enabled. The area that does fulfill safety requirements is inner circle inside this warning zone and that uses safety inputs and causes emergency stop. So can you explain me how to switch SR_OV_RED on and off with sps.sub?


    Tero

    Hi,

    Ok pls tell me how to get this kind of functionality to happen with safety functions? I admit I should of made a better question and representation. I am working for a research and development institute. We are studying and researching new ways in the area of robotics. I have been assigned to study if this kind of functionality is possible by my boss. I will study this and make my report. And it is his decision if he assign our safety experts to see if it conforms to safety regulations or not. This is studied in our lab environment only not in production environment. I should of formed my question this way "I have a push button 10 feet away from robots reach area. When this button is pressed I would like robot slow down to 10% of its speed, and when it is released go back to 95%". Because this is the case actually. Now I mentioned safety scanner and my question was doomed. Thank you Davidina for help and pointing me to right direction. As currently using sps.sub has been only way to get this to work like intented. I originally tried using VRED safety function for this but it does alarm if triggered during motion.


    Tero

    Edited once, last by terok ().

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