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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."

3 of 149 comments (clear)

  1. 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.

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    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.
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  2. 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.