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Industrial Robot Arm Becomes Giant Catapult

Posted by Soulskill on 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."

21 of 149 comments (clear)

  1. double entendre by User+956 · · Score: 5, Funny

    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.

    --
    The theory of relativity doesn't work right in Arkansas.
    1. Re:double entendre by SnowZero · · Score: 4, Insightful

      The right was granted in the age of muzzle loaders. ...and cannons[1], mortars[2], bombs[3], and landmines[4]. Most people seem to forget that.

      [1] [2] [3] [4]
    2. Re:double entendre by e4g4 · · Score: 4, Funny

      The right to bare arms does not give you the right to have nuclear warheads No, but it does give people the right to wear hideous hawaiian shirts, which is almost as bad.
      --
      The secret to creativity is knowing how to hide your sources. - Albert Einstein
    3. Re:double entendre by Crypto+Gnome · · Score: 3, Insightful

      .... the founding fathers' intention of keeping the population armed so that the people have a "last resort" should the government cease to act in the interests of the general populace.... It never ceases to amaze me ... Exactly specifically WHAT EXAMPLE OF "government ceasing to act in the interests of the general populace" are you all waiting for?

      Does "the president" need to DROP NUKES on The Continental US of A before people WAKE UP and DO SOMETHING?

      Or do you all think that "having a vietnam war" in the middle of the desert is in the interests of the general populace?
      --
      Visit CryptoGnome in his home.
    4. Re:double entendre by rohan972 · · Score: 3, Insightful

      Personally, I think it was in a different historical context, but the appropriate response is not reinterpretation of the constitution but amendment, for which there is a proper procedure. I think the US constitution (2nd amendment) is fairly clear and in the context of the revolution seems to mean full military armament. Taken in the context of a world in which nuclear weapons etc exist, I do not think this is a good idea. However, if the constitution is reinterpreted according to every change in technology (or other historical context) it ceases to be really usefull as a constitution as I understand it.

      Where we draw the line between personal nuclear arms and total weapons bans is not the point as I see it. The point is that the government is supposed to be regulated/limited by the constitution. Where the government is freed to reinterpret the constitution at will this is no longer the case and political liberty is effectively over. Under such a system, you no longer have rights in any real sense, you have priveleges granted or revoked by the government.

      I dont believe he ever said he wasn't scared of machetes.

      I put the comments about fear of inanimate objects and machetes in separate paragraphs for a reason. It is two separate points being (1) It is silly to fear inanimate objects, and (2) prohibition of firearms does not prevent murder or mass murder. Point (2) is not opinion, it is demonstrable fact. Sure it is easier with more advanced weapons, but that makes people equal, rather than the weak being subject to the violence of the strong.

      You're not afraid of inanimate objects designed specifically to kill people? how strange. You're getting at the 'guns dont kill people, people kill people' thing, and you know what? people using guns kill people with surprisingly more efficiency than people without guns killing people.

      No, I'm not afraid of objects designed specifically to kill people. I've owned guns in the past and they never struck fear into me. I've known other people, police etc that have guns and they didn't strike fear into me. In any case, firearms regulation where I live has given rise to a thriving illegal gun trade, according to media reports. I don't really see the point of the laws. Any anyone with high school level chemistry and some initiative can make high explosives anyway. For people that don't know how, there are always molotov cocktails. I can see it's possible to prevent people having nukes, but for personal weapons it just seems to be a waste of time to legislate against them.

      We are all surrounded by things that can kill, electricity, knives, cars. If we are going to let everyone buy petrol, without restriction and without license, then laws against personal firearms are just a farce.

      --
      http://marriedmansexlife.com/
  2. It's not a catapult. by zippthorne · · Score: 5, Informative

    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.

    --
    Can you be Even More Awesome?!
    1. Re:It's not a catapult. by donscarletti · · Score: 4, Informative

      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.
      --
      When Argumentum ad Hominem falls short, try Argumentum ad Matrem
    2. Re:It's not a catapult. by Nefarious+Wheel · · Score: 4, Interesting
      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.

      --
      Do not mock my vision of impractical footwear
  3. Re:I for one... by scottrocket · · Score: 4, Funny

    ...and the next time the mongols attack our shitty walls in their motorhomes, we'll be ready!

  4. Let me be the first by Psychotria · · Score: 3, Funny

    to offer my services as a target for this thing. Catapult a beer my way every 15 minutes. Thanks.

  5. I can see the future now, and you DON'T want to be by davidsyes · · Score: 4, Funny

    on the WRONG arm of the LAW

    --
    Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
  6. Graphical UI by iminplaya · · Score: 5, Funny

    gorilla.bas?

    --
    What?
  7. HD Camera by Anonymous Coward · · Score: 5, Insightful

    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...

    1. Re:HD Camera by plover · · Score: 4, Funny

      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.

      --
      John
    2. Re:HD Camera by wintersynth · · Score: 5, Interesting

      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.

    3. Re:HD Camera by manamonkey · · Score: 3, Informative

      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.

    4. Re:HD Camera by errxn · · Score: 4, Insightful

      Sorry, but you intended to return it from the very start. The lame excuse that the camera sucked does nothing to change that fact, and really just makes you seem like that much more of a tool.

      --
      In Soviet Russia, Chuck Norris will still kick your ass.
  8. Calculon proves even robot arms can move up by 4d4m · · Score: 4, Funny

    As we can see from Calculon, you aren't just stuck as a robot arm. Thespomat, David Duchovny - the sky is the limit.

  9. Catapult? by Teufelsmuhle · · Score: 5, Funny

    It's not a real catapult unless it's flinging cows or pianos.

  10. Ah, memories... by Dr.+Manhattan · · Score: 3, Interesting
    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.

    --
    PHEM - party like it's 1997-2003!
  11. Not the first robot to fling something. by karlandtanya · · Score: 4, Interesting
    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.

    --
    "Reality is that which, when you stop believing in it, it doesn't go away." - Philip K. Dick