Ourobot: What Happens When A Snake Bot Swallows Its Own Tail

July 20, 2016 by Elliot Williams 21 Comments

For all their joking about “reinventing the wheel”, the team behind Ourobot made a very cool robot (German, automatic translation here). The team, at the University of Applied Sciences in “Bielefeld, Germany“, built their wheel out of twelve segments, each with its own servo motor, a 3D-printed case, and a pressure sensor mounted on the outside of the wheel. The latter, plus some clever programming, allows the robot wheel to vary its circular gate and climb up over obstacles automatically.

There are a bunch of interesting constraints in designing the control for this bot. The tracks on the ground, naturally, have to adjust their relative angles so that they lie each flat on the surface, even if that surface isn’t itself flat or level. The segments in the air are unconstrained, but the sum of all the servos’ interior angles has to add up to 1800 degrees, and these angles control where its center of gravity is.

Our head is spinning. The paper, “OUROBOT – A Self-Propelled Continuous-Track-Robot for Rugged Terrain” is unfortunately behind the IEEE paywall, but goes into detail if you can find it. Continue reading “Ourobot: What Happens When A Snake Bot Swallows Its Own Tail” →

3D Printering: G-Code Post Processing With Perl

July 20, 2016 by Moritz Walter 31 Comments

Most of our beloved tools, such as Slic3r, Cura or KISSlicer, offer scripting interfaces that help a great deal if your existing 3D printing toolchain has yet to learn how to produce decent results with a five headed thermoplastic spitting hydra. Using scripts, it’s possible to tweak the little bits it takes to get great results, inserting wipe or prime towers and purge moves on the fly, and if your setup requires it, also control additional servos and solenoids for the flamethrowers.

This article gives you a short introduction in how to post-process G-code using Perl and Slic3r. Perl Ninja skills are not required. Slic3r plays well with pretty much any scripting language that produces executables, so if you’re reluctant to use Perl, you’ll probably be able to replicate most of the steps in your favorite language.

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Simple Beetle Robot Uses Smoking Soldering Iron

July 20, 2016 by Al Williams 34 Comments

As robot projects go, [creative ideas km]’s isn’t going to impress many Hackaday readers. Still, as an art project or something to do with the kids, it might be fun. But the reason it caught our interest wasn’t the actual robot, but the improvised soldering iron used in its construction.

The robot itself isn’t really autonomous. It is just a battery, a motor, and a switch. The motor vibrations make the robot scoot around on its bent copper wire legs. Some hot glue holds it all together, but the electrical wiring is soldered.

If you look at the video below, you’ll see the soldering is done with an unusual method. A disposable lighter generates a flame that hits an attached copper wire with a coil wound in it. The coil acts as a heat exchanger, and the wire becomes a soldering iron tip.

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Hot Russian Tubes

July 20, 2016 by Elliot Williams 33 Comments

On the heels of our post on retro-Soviet transistor teardowns and die-shots, [nikitas] wrote in to tell us about a huge thread on rare vacuum devices of all varieties: oddball cathode-ray tubes, obscure Nixies, and strange Soviet valves. We thought the other forum post was overwhelming at just over 110 pages, but how about 391 pages (and counting) of blown-glass electronics?

If you read through the decaptholon, we mentioned that a particularly enthusiastic poster, [lalka], looked to be cataloguing every Soviet oscillator circuit. It turns out that he’s also the one behind this incredible (random) compendium of everything that’s had the air sucked out of it.

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