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Robotics Hardware

Industrial Robot Arm Becomes Giant Catapult 149

Posted by Soulskill
from the excellent-gift-ideas dept.
wintersynth brings us a story about a group of enthusiasts who made a catapult out of a 2,800lb industrial robot arm. They used it to launch bowling balls, fireballs, and cans of beer toward a stationary target, and they controlled the catapult's aim with a graphical UI on a laptop. "I wanted to be able to control the rotation of the robot so we could aim the robot from the laptop, but I quickly realized that since the desert is so flat, we could do some basic ranging on the target too. I also wanted the targeting to be overlaid in 3d over a photograph of the target area. The software needed to control the robot like an MMO or RTS game. I suspect that video games, in general, have some of the most optimal control interfaces. I wanted to try a control scheme similar to the area effect spell targeting in World of Warcraft."
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Industrial Robot Arm Becomes Giant Catapult

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  • by User 956 (568564) on Thursday January 17, 2008 @11:31PM (#22089404) Homepage
    wintersynth brings us a story about a group of enthusiasts who made a catapult out of a 2,800lb industrial robot arm.

    And it's all thanks to the second amendment.
    • wintersynth brings us a story about a group of enthusiasts who made a catapult out of a 2,800lb industrial robot arm.

      And it's all thanks to the second amendment.
      Cyborg bears can't be far behind...
    • Well, if they combined this with a RealDoll, they might have something useful.
    • I thought you meant this [deviantart.com].
  • Hack a Day had this story yesterday, http://www.hackaday.com/2008/01/16/bowling-industrial-robot-style/ [hackaday.com]. Good to see it make slashdot, though. It's also interesting its on the "mana potion" energy drink site.
  • It's not a catapult. (Score:5, Informative)

    by zippthorne (748122) on Thursday January 17, 2008 @11:35PM (#22089430) Journal
    It's a trebuchet, as can clearly be seen from the sling which holds the bowling balls. It also does not have an optimal sling length, but that just makes the robot itself all the more impressive.
    • Re: (Score:3, Insightful)

      by Psychotria (953670)
      You're correct. Except that a trebuchet is still a catapult.
    • by donscarletti (569232) on Thursday January 17, 2008 @11:51PM (#22089540)

      It's a trebuchet, as can clearly be seen from the sling which holds the bowling balls. It also does not have an optimal sling length, but that just makes the robot itself all the more impressive.
      A trebuchet is powered by a counterweight, this thing is powered by some sort of mechanical actuators meaning that it certainly is not a trebuchet. As for slings, the Roman onager used slings despite being driven by torsion rather than counterweights. Of course back then a catapult was defined as a sinew torsion based crossbow that that fired a spear. A ballista was similar but fired rocks instead, though these days we call an onager a catapult, a catapult a ballista and don't really have a name for a ballista.
      • by Nefarious Wheel (628136) * on Friday January 18, 2008 @12:30AM (#22089776) Journal
        A trebuchet is powered by a counterweight, this thing is powered by some sort of mechanical actuators meaning that it certainly is not a trebuchet. As for slings, the Roman onager used slings despite being driven by torsion rather than counterweights. Of course back then a catapult was defined as a sinew torsion based crossbow that that fired a spear. A ballista was similar but fired rocks instead, though these days we call an onager a catapult, a catapult a ballista and don't really have a name for a ballista.

        There were non-counterweight trebuchets as well, called "traction" trebuchets. Instead of a counterweight you had a number of people tugging on ropes. I had one based on this model built for me for SCA combat as the result of a siege engine competition (Stormhold) some years ago. 60-90 metre throws with a cargo of softballs was customary with a 6 metre composite rattan arm. One advantage of a traction trebuchet is it's more mobile as you don't need to score or drag a tonne or so of counterweight along to the launch site.

        So to stay on topic, I think you could call the robot arm a form of trebuchet. I've not seen onagers with slings in my researches though, will look for that. Onagers btw were so named because of the bucking motion they make, mitigated by curved ends of their foundation rails. Onager = Donkey in Latin. They were also called "rocking donkeys".

        And another name for Ballista could be "ZOMG Look at the size of that effing crossbow!". They didn't always use rocks, some of them used mucking great iron bolts.

      • Re: (Score:2, Funny)

        by JustOK (667959)
        aren't ballistas the people who go to college for four years in order to serve drinks at starbucks?
      • by Mike1024 (184871)
        this thing is powered by some sort of mechanical actuators meaning that it certainly is not a trebuchet.

        Those are AC servo motors. From the colour of the robot and be blurry photos I think it's a KUKA KR 150-2 K [kuka.com] or something similar.
      • Your ideas intrigue me and I'd like to subscribe to your newsletter.

        P.S. Can I come over to your house and launch a piano from your trebuchet? (I assume you have a few)
    • Re: (Score:3, Funny)

      by Ours (596171)
      Indeed, source code for the robot states that correctly.
  • AWESOME. They do have a good point of the video game interface. Moving maps, with hotkeys...though I doubt they have the complexity for everything.
  • by Psychotria (953670) on Thursday January 17, 2008 @11:41PM (#22089476)
    to offer my services as a target for this thing. Catapult a beer my way every 15 minutes. Thanks.
  • by davidsyes (765062) * on Thursday January 17, 2008 @11:46PM (#22089504) Homepage Journal
    on the WRONG arm of the LAW
  • by iminplaya (723125) <iminplaya.gmail@com> on Thursday January 17, 2008 @11:55PM (#22089562) Journal
    gorilla.bas?
  • HD Camera (Score:5, Insightful)

    by Anonymous Coward on Friday January 18, 2008 @12:01AM (#22089602)
    Let me get this straight... they "Rented" the camera by buying it at Fry's and returning it?

    I'm sure some people will defend this tactic, but its stuff like this that causes awesome return policies at stores to be restricted, and prices to go up. (as recently happened at CostCo)

    I can't believe they posted that tidbit on the site...
    • by toadlife (301863)
      I bought a reciprocal saw the other day at Home Depot. One of the saws' outside packaging was missing - it was a return, but it as the only DeWalt left. I asked the store clerk to open it (it had anti-theft a lock on the handle) so I could make sure all the parts were there. Upon inspection I found that the instructions, and saw blades were missing and the saw itself was extremely dirty and had a gash on the front hole where the saw blade attaches. Some asshole had bought it, used it on a job and then retu
    • by plover (150551) * on Friday January 18, 2008 @12:28AM (#22089774) Homepage Journal

      Let me get this straight... they "Rented" the camera by buying it at Fry's and returning it?

      I'm sure some people will defend this tactic, but its stuff like this that causes awesome return policies at stores to be restricted, and prices to go up. (as recently happened at CostCo)

      Yeah, I was pissed at them when I read this too. I hope that when Fry institutes a 20% open-box charge on returns, that everybody look this guy up and send him a thank you note. Wrapped around a bowling ball.

      • Re:HD Camera (Score:5, Interesting)

        by wintersynth (915045) on Friday January 18, 2008 @01:05AM (#22089950)
        Okay, I have to admit, we felt pretty bad about this "renting" tactic until we actually tried the camera. It was hands-down the worst HD camera I have ever used. I mean seriously, it had all sorts of proprietary software with weird codecs so that the footage was extremely difficult to transcode at high resolution.

        I felt absolutely no remorse returning that thing. I know, that still doesn't make it right, because we didn't know that going into it. But I hope it is at least a mitigating factor. Plus, I give Fry's tons of (non-"rented") business, and their awesome return policy is a big part of the reason.
      • I hope that when Fry institutes a 20% open-box charge on returns, that everybody look this guy up and send him a thank you note. Wrapped around a bowling ball.
        ...Delivered by catapult, I assume?
      • Re: (Score:3, Informative)

        by manamonkey (1222298)
        Our budget was $1K to get this all done and a great deal of that hinged on the resources we had available between the three of us. Our camera loan fell through last minute (literally) and we did not have time to research the purchase of a new one. If the cam was good we would have kept it, but it really was a piece of crap. We are about as far from trust-fund kids as you can get and that was not my first or last Fry's return for a piece of disappointing hardware.
    • And also where did they "borrow" an industrial robot? (and then get permission to use it as a toy?)

      You don't exactly see them sitting out on the street every day....
    • Watching the videos, they have a rather large generator, a boom forklift, the robot, the robot power controller, a pile of bowling balls, and an RV "target." There's serious money here; planning too. They didn't just boogey out into the desert after drinking a few beers one weekend. I fail to understand how they couldn't "budget" for a camcorder ... maybe borrow one from the neighbor or yell upstairs and ask to borrow mom's?

      What, they needed the HD camera to make their YouTube posting look better?
    • This is VERY common at Fry. They have a libral return policy that is NOT likely to change. The return policy is the main reason many people put up with shopping there. The place is a mess and staffed with people who don't know anything about the products being sold. But everyone knows that it they don't like whatever they bought they can just bring it back within 30 days no questions asked. My brother worked in IT for some company and they wanted to buy vidio cards for their computers. So he goes to F
  • by 4d4m (584216) on Friday January 18, 2008 @12:08AM (#22089636) Homepage Journal
    As we can see from Calculon, you aren't just stuck as a robot arm. Thespomat, David Duchovny - the sky is the limit.
  • "The software needed to control the robot [is] like an MMO or RTS game."

    Oh I can see it coming... "OMG fsking WALL HAX N00BZ!" ...shouted right before you get shelled by 16 pound bowling balls. :(

  • Seriously, they threw bowling balls 120 feet. Yawn.
    • by hey! (33014)
      Yes, but it is a prototype made with off the shelf components. Scale the motors up 20x and give it a hopper capable of holding a couple thousand incendiary bowling balls and it would be a lot more impressive.
  • a giant wooden badger?
  • Catapult? (Score:5, Funny)

    by Teufelsmuhle (849105) on Friday January 18, 2008 @12:20AM (#22089714)
    It's not a real catapult unless it's flinging cows or pianos.
  • ...is plug in the monkey [slashdot.org]!
  • Why waste beer? Oh the humanity!
  • Because honestly, for what that arm was, it could have fired alot further than they had it going. I built a floating arm trebuchet 2 years back for my high school senior project and it had a least twice the range of that arm.( It could fire a half gallon of water about 250 feet. )I admit, that may have been less weight than their arm was firing, but that was because I only had about 300 pounds of counterweight. Their problem is in the release time, and the sling could stand to be a bit longer. Its still pr
    • Nice idea, but there's something just so ... sexy about it being a giant robot arm.

      I like the vision-control guidance system too. Some MAJOR geek points in all of that in my book.
  • That's a recipe for an awesome game of beer pong.
  • They said they had some trouble determining the optimal movement of all the motors for maximum range. iirc, when trying to accelerate something, a 'whiplike" motion is preferred, similar to how a pitcher throws a fastball.
  • Ah, memories... (Score:4, Interesting)

    by Dr. Manhattan (29720) <sorceror171@@@gmail...com> on Friday January 18, 2008 @09:09AM (#22091868) Homepage
    I used to work for an industrial robot company. I worked on the big arms that carried spot-welding guns around, mostly for the auto industry. Those arms were strong - there was one case where the gun welded itself to the truck frame it was building (as will happen if you don't clean the tips enough) and the robot kept right on going, and ended up tossing a truck body into the aisle when it returned to rest. Thankfully, no one was hurt.

    But that incident, among others, spurred work to develop collision detection. They finally got some software running on the DSPs that'd estimate what the current to the motors should be, and measure what it actually was; too big a difference and the robot would halt. And then comes the fun part...

    I got to test it.

    For six months, my paid job was to take huge industrial robots and bang them into things.

    I'm pure software now, and it's fun and pays better... but I still think about those days with fondness.

    • Re: (Score:2, Interesting)

      by psychosmyth (1222402)
      Haha, Dodged a few castings from a DCpress recently. Rejected a bad cast and the arm just shook it in the air and tossed it across the floor at my feet. The operator had to reset it a few times. I swear it was mocking me.
  • by karlandtanya (601084) on Friday January 18, 2008 @09:21AM (#22091948)
    In the floorpan line of a well-known auto manufacturer, the safety folks wanted to test the OSHA safe stopping distance calculation used to place some light curtains.

    The way you protect workers from getting killed by a robot (and these things are way stronger than you think, even after seeing it fling rocks) is to put up light curtains around the robot.
    The OSHA safe stopping distance calculation is used to prove that the hazardous motion will stop in the time it takes the person to traverse the light curtain and come into contact with the equipment.

    So, the safety folks find the robot with the biggest, fastest moving load on the line--the floorpan skin transfer robot. A floorpan skin is basically a sixty-pound razor blade.
    The end effector held onto the floorpan skin with suction cups, which are a cost-effective and reliable method for the process.

    The robot guys set up a test, where they got all 6 axes of the robot moving in such a manner that the end effector achieved its maximum possible speed.
    Not something you'd normally do, but a worst-case scenario for use as safety systems challenge.
    We all wanted to see this robot haul ass, so the safety folks had us all standing back...
    Robot dude picked up the TP and initiated the path at 100% speed...
    Somebody waited for the arm to get to full extension and speed...and stuck their hand into the light curtain.

    The robot stopped almost instantly--well within the expected stopping distance.
    No way that person would have been injured by the robot.

    The skin (remember the sixty-pound razor blade) stopped a couple bays over.

    Hard clamps were added to the end effector and the test was repeated with improved results.

  • ...SCO already went under.

    rj
  • The Carnegie Science Center in Pittsburgh currently has a robotic arm that looks just like this, but it plays basketball [carnegiemuseums.org]. It is a basketball catapult.

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