Kuka robot project and difficulties

  • Hi Guys,


    I was recommended to come on here for advice on setting up my robot. I am mechanical engineering student who recently went a bit loopy an purchased a second had robotic arm during lockdown and have extended the family shed to fit the arm and I'm trying to convert it to milling on a "shoe-string" budget.


    It has been a somewhat complicated process as the Kuka had been highly engineered to work in a specific context and workspace and had three automation companies collaborating to achieve the final result (it was previously hung from the ceiling and used as a water jet cutter). Currently my friend Dave and I have been trying to figure out how to work backwards to make the robot a more standard set up to work for milling.


    Alema Automation, which has since been bought by kuka, was one of the companies working originally to set up the robot. The computer seems to run an Alema Automation program in the background and I don't have a password for it in expert mode. I was wondering if someone on here new the password.


    So far the servo controllers talking to each other and the pendant turns on, however some of the pervious iteration's inputs cause error codes ( it had an encoder on the first axis and another computer in the system, both of which are not being used or present).


    I am going to start to use Kuka work virtual to re program the hard drive to our application.


    Has anyone had to re-purpose a robot like this and if so were there any difficulties or things I should be considering.


    Cheers,

    Chris


    IMG_20201030_200004.jpg.5b91a80089d3bde9

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  • Hello, it would be helpful if you could post the controller and KSS versions.

    If this is a newer controller, the orientation change might be as simple as changing $robroot to Nullframe.


    As for milling with a used robot, depending on wear, you might need to remove material without hard change in direction (no 180 degrees turnaround on the spot) as gear backlash will momentarily mess up positioning.


    However you are going to generate milling code, make sure it avoids singularities.

  • Guys,


    I have been sucked into this vortex and at first I was like - Chris, are you serious?


    Chris bought this sight unseen for a crazy low price from an industry auction site. At the time we were all locked inside our homes for 23 Hours a day so the market was non existent.


    It has been turned ON for a around 100 days. 2500Hrs powered time. We think ex Government. Chris has the Midas Touch.


    I only have a partial copy of the hard drive at home as another friend is trying to clone this now.

    So i think the version is 5.4.13


    From.......//KRC1_CD\INTERNAT\KRCUPD/sp.reg

    ;===========================

    ;KRCVersion: V5.4 KUKA

    ;===========================

    ;Version: 5.4.13 KUKA

    ;Last changed: 11:38 10.07.2007

    ;Changed by: GST

    ;===========================


    My synopsis.


    • Chris is braver than me and I do stupid stuff daily but I would have been divorced if I put a stupid low bid on something thinking I would be out bid. ha ha I would like to be young again.
    • The Robot is like new. Amazing.
    • I know Chris and his dad from a car club and there are a few of us who are helping Chris realise a dream of building his own car.
    • His dad and Chris extended the shed to locate it out of the weather. Dad of the year i.m.o.
    • I think there a few bits missing. There is an encoder and wiring back to the controller but no where to attach it. The encoder is mounted on the primary vertical pivot point. We have an encoder fault error message. So I need to modify the code some how. There is a file called Postest.sub with boolean set high if encoder is OK. But i am sure there is more to this as the water jet cutter components were sold off separately. If only we knew.
    Code
    ; TmpPtOk is true if all other axis are Ok
    ; External axis checking
    IF ($EX_AX_NUM==1) THEN
    TmpPtOk=TmpPtOk AND ((RobAxisAct.E1>=(ParkPos.E1-ParkingThreshold)) AND (RobAxisAct.E1<=(ParkPos.E1+ParkingThreshold)))
    ENDIF
    RobAtPark=TmpPtOk


    • We have wired loops on the Alema Devicenet I/O to remove the hardware interlocks. All errors are gone for digital hardware. I would like to keep this remote Dig I/O it as it might be useful later down the road.
    • I really want Chris to learn and he is willing to help his mates at Uni so there are making this a very safe install as the controller will be outside of the shed as will the operator (Chris) behind interlocked doors.


  • I am not really familiar with this type off controller. It is obviously not a standard controller. But maybe i can help point in the right direction.

    • First to make things easier to diagnose write down the complete errors with numbers. the more information the better. some pictures could not hurt either
    • Second i can see from the picture you have 7 drives in your cabinet which means this machine had an extra axis in the past. You would have to change the configuration and turn off the extra axis (maybe even take the drive out, not really sure about that one but there are topics on this forum about adding and removing an extra axis).
    • Your first goal should be jogging the robot manually, i is not mentioned but i presume you cannot move the robot just yet.

    Every problem has a solution, that isn't the problem. The problem is the solution.

  • Most of the time, robots of that size cannot be "flipped" without also changing the counterbalance cylinder. As it stands, right now the counterbalance may be "countering" gravity in the wrong direction. Software changes won't fix this.


    The default password should be kuka -- all lowercase. Alema never changed the passwords in my experience.


    Take an Archive of the robot, then post the am.ini file. That'll tell us what options this robot is set up with.


    We definitely need the full details of the active fault messages. Hit "Ackn All", then post the messages that don't clear. And do not just post photos of the pendant, that's a good way to get people to bail out of the thread.


    Cloning the hard drive should be simple -- it should be a normal IDE/PATA drive, with two partitions, with Win98 installed. Probably formatted in NTFS. Definitely clone it before starting anything, that clone will be the only catastrophic recovery in the event the robot is "bricked," and there's a good chance of doing that by accident while you're trying to get this beast running.


    The "nuclear option" would be to re-install KSS from the D: partition, but that probably shouldn't be the first option.


    If you can get the password, probably a first step would be to use the Axis Configuration tool (under the Setup menu, IIRC) to remove whatever external axes the robot thinks it has, but no longer does. From the photo, it appears that the cabinet only has 6 servo amps, so this will be necessary to resolve any errors relating to "E1," "E2," etc.

  • A brief reply, more details later.


    Leon,

    No movement yet. Encoder error holding us back. I appreciate your interest.

    If we can get this going, it is going to be the best Christmas ever! :P


    Skyefire,

    Got it.

    We tried all sorts of P/W for Alema software. I guess it is encrypted in an .exe file so not much luck there either. (Not stored in plain text that I can see)


    am.ini



    I'll make a separate post on .ini files.

  • Skyefire,

    Got it.

    We tried all sorts of P/W for Alema software. I guess it is encrypted in an .exe file so not much luck there either. (Not stored in plain text that I can see)

    What Alema software? Are you trying to log into the robot, or some separate computer? Alema V6000 and V7000 always ran on a separate PC, and "puppeted" the robot through ProfiBus.


    Do you want to run the robot through the Alema software? Honestly, you'd be better off junking the Alema stuff altogether and running the robot directly. For one thing, all the Alema software I'm familiar with depending on a position program created using ProcessSimulate, which last I checked runs about $20k US per license.


    Errors:

    Line 33 of the spreadsheet indicates you're in Expert mode on the robot? And Line 31 shows you in Administrator.


    The Mastering errors are simply signalling that the robot needs its axes re-zero'd. I'm assuming you don't have an EMT? You can use the Dial Mastering option on the pendant, but you'll have to get the physical zero positions for each axis by feel, depressing the Mastering Pin with a non-metallic tool.


    Line 13 means that the robot is looking for a 7th axis (E1). You'll need to remove that. The easiest way is probably using the AxisConfig tool, which should be located under the SETUP menu tree. Change the number of external axes to 0.

  • Skyefire - Thanks


    You and Robot Forum have instilled a lot of confidence in us in a very short time.


    Alema S/W is on the PC and auto starts on boot after the Kuka loads. We don't really know what it does other that this system had a water jet cutter. I agree, we are better off without it. I think it might be as simple as getting into the services in WinXP and turning it off (Disable / manual???) or uninstalling the software.


    However IF there is a hand shake to the other computer, we need to modify the Kuka logic to mask that out. What application would I run to edit the logic?

    The 7th axis. We plan to remove this as soon as the HD is cloned. We can pretty much go to town on the software once we have a few backups.


    About us.

    I live about 1 hour from Chris. The Hard Drive is being cloned by another friend who is a further 1.5 hours away and he has young kids and a demanding day job.

    I worked on PLC's and motion controls years ago so I feel pretty confident we will make progress for Chris. Chris and his dad also help out many in our larger car group so I am sure Chris will return many a favour here at Robot Forum.

    FYI - we are in Melbourne Australia. We were in lockdown and now out and about but we are all trying to catch up on work and home projects so momentum on this really fun project will ebb and flow.


    Dave


    city-skyline-yarra-council-plan-898.jpg

  • Most of the time, robots of that size cannot be "flipped" without also changing the counterbalance cylinder. As it stands, right now the counterbalance may be "countering" gravity in the wrong direction. Software changes won't fix this.

    We are having serious discussions about mounting the Kuka upside down. Chris wants to make foam bucks for fibre glass to make replica cars. To me it makes sense to hang it up as he can make bigger patterns by machining foam on the floor. The Kuka should stay cleaner too. I have no idea how we are going to do this but Chris is one determined human tornado.

  • About mounting the robot upside down, it will depend on the mechanical arm type.


    I'm not sure, but if I recall correctly, the spring system is different between floor mounted and ceiling mounted robots.


    Robot shoud have a small metal plate placed somewhere near its base. This plate will have the ARM TYPE info.


    If You can check this info (and post here) will be easier to determine if is possible achive this mounting setup.

  • A long day of chasing wiring. Making sure we are right to go as soon as the hard drive is available.

    We had a deeper look at the counter balance and it appears we need to either make or modify the balance (spring) or Mount it upside down by cutting a hole in the roof of the shed and make a frame to lift it about a meter above the current roof height and somehow make a frame to hold it up there.


    Still a lot cheaper than a large CNC milling machine and a lot more fun.


    Chris, please thank your Mum and Dad for lunch. :)

  • Before you are going to cut holes in your roof it could not hurt to ask Kuka for a quote for a replacement balancing spring.

    I admit it might be more of a challenge (or a lot more fun as you like to put it) to hang the robot on the roof, but i always want to have a plan B.

    When you do decide to ceiling mount the robot, take in mind that a robot of this size needs a serious structure to be mounted to. Not just for its own weight but also the dynamic forces that it can create when accelerating en decelerating. If i am not mistaken in the robot specifications (you can download those from the kuka website) it should list the forces your mounting place should be able to withstand.

    Every problem has a solution, that isn't the problem. The problem is the solution.

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