Hackaday Prize Entry: Octo, The Robotic Walker

Walkers like the Strandbeest are favorites due in part to their smooth design and fluid motion, but [Leandro] is going a slightly different way with Octo, an octopodal platform for exploring rough terrain. Octo is based on the Klann linkage which was developed in 1994 and intended to act as an alternative to wheels because of its ability to deal with rough terrain. [Leandro] made a small proof of concept out of soldered brass and liked the results. The next version will be larger, made out of aluminum and steel, and capable of carrying a payload.

The Strandbeest and Octo have a lot in common but differ in a few significant ways. Jansen’s linkage (which the Strandbeest uses) uses eight links per leg and requires relatively flat terrain. The Klann linkage used by Octo needs only six links per leg, and has the ability to deal with rougher ground.

[Leandro] didn’t just cut some parts out from a file found online; the brass proof of concept was drawn up based on an animation of a Klann linkage. For the next version, [Leandro] used a simulator to determine an optimal linkage design, aiming for one with a gait that wasn’t too flat, and maximized vertical rise of the leg to aid in clearing obstacles.

We’ve seen the Klann linkage before in a LEGO Spider-bot. We’re delighted to see [Leandro]’s Octo in the ring for the Wheels, wings, and walkers category of The Hackaday Prize.

[Hari] Prints an Awesome Spider Robot

Although we have strong suspicions that the model’s designer failed entomology, this spider robot is very cool. [Hari Wiguna] made one, and is justifiably thrilled with the results. (Watch his summary on YouTube embedded below.)

Thanks to [Regis Hsu]’s nice design, all [Hari] had to do was order a hexapod’s dozen 9g servos for around $20, print out the parts, attach an Arduino clone, and he was done. We really like the cutouts in the printed parts that nicely fit the servo horns. [Hari] says the calibration procedure is a snap; you run a sketch that sets all the servos to a known position and then tighten the legs in place. Very slick.

The parts should print without support on basically any printer. [Hari]’s is kinda janky and exhibits all sorts of layer-to-layer irregularities (sorry, man!) but the robot works perfectly. Which is not to say that [Hari] doesn’t have assembly skills — check out the world’s smallest (?) RGB LED cube if you think this guy can’t solder. Of course, you can entirely sidestep the 3D-printed parts and just fix a bunch of servos together and call it a robot. It’s harder to make building a four-legger any easier than these two projects. What are you waiting for?

Continue reading “[Hari] Prints an Awesome Spider Robot”

Giant Spider Roams The Streets

There is a giant spider the size of  a house stretching its massive, delicate legs as it parades through the French city of Nantes. Is the Arthropod Apocalypse upon us? Fortunately not, for this arachnid is the latest in a series of performance pieces by a French theatre company, La Machine.

Like the rest of La Machine’s productions, this spider is a large hydraulically controlled model driven not by a computer with a single operator but by a team of operators perched inside and underneath the mechanism who turn the operation of the spider’s legs into a piece of complex choreography. They in turn are aided by a team on the street who ensure that any manoeuvres are executed safely. The spider only gives the appearance of walking as it is supported on a hydraulic arm from a wheeled vehicle that carries its power plant, so freed of the requirement for support from its legs it can move with extreme grace.

The video below shows the spider inching its way underneath a set of tram cables. There is more video on the page linked above.

Continue reading “Giant Spider Roams The Streets”

Fail of the Week: Arachno∙fail∙ia

Going down the list (FCC, CE, UL, etc.) we can’t think of a regulating body that will test for this failure mode. Reportedly, a $1M irrigation system was taken down by a spider. And an itsy-bitsy spider at that.

This fail turned up as a quick image post over on /r/mildlyinteresting but I wasn’t the only electronics person attracted like a moth to a flame. Our friend [Sprite_TM] popped in to answer a question about conformal coating. Seems this board was sealed in a waterproof enclosure but was obviously not conformally coated.

fotw-spider-short-relay-diagram[Sprite_TM] also helped out with some armchair-engineering to guess at what happened. It’s not hard to tell that the footprint on the board looks like a set of mechanical relays all in a line. He looked up the most likely pinout for the relay.

We’ve superimposed that pinout on the board to help illustrate the failure. High voltage comes in on the pin shown with the red trace leading away from it. On either side of that pin are the connections for the low voltage coil which switches from normally closed (the pin in the upper right that is not connected to anything) to the normally open pin (which has the wide trace leading away from it).

So there sat the high voltage pin in between the coil pins when, along came a spider. It shorted the pins and presumably all the way back to the power supply for the low voltage rail. [Fugly_Turnip] (the OP) share some additional detail about the system and this failure; in addition to this card it fried the control module as well.

Another comment on the same thread shares a different story of two boards mounted next to each other with a bug shorting a 1/4″ air gap between two boards and causing similar carnage. Have you encountered Arachno-fail-ia of your own? Let us know below.


2013-09-05-Hackaday-Fail-tips-tileFail of the Week is a Hackaday column which celebrates failure as a learning tool. Help keep the fun rolling by writing about your own failures and sending us a link to the story — or sending in links to fail write ups you find in your Internet travels.

Hexapod Tank from Ghost in the Shell Brought to Life

Every now and then someone gets seriously inspired, and that urge just doesn’t go away until something gets created. For [Paulius Liekis], it led to creating a roughly 1:20 scale version of the T08A2 Hexapod “Spider” Tank from the movie Ghost in the Shell. As the he puts it, “[T]his was something that I wanted to build for a long time and I just had to get it out of my system.” It uses two Raspberry Pi computers, 28 servo motors, and required over 250 hours of 3D printing for all the meticulously modeled pieces – and even more than that for polishing, filing, painting, and other finishing work on the pieces after they were printed. The paint job is spectacular, with great-looking wear and tear. It’s even better seeing it in motion — see the video embedded below.

Continue reading “Hexapod Tank from Ghost in the Shell Brought to Life”

Learning Single-Filament Printing Strength from Arachnids

If you can get over how creepy spiders can be there’s a lot to learn from them. One of nature’s master-builders, they have long been studied for how they produce such strong silk. What we hadn’t realized is that it’s not strictly cylindrical in nature. The spider silk exhibits intermittent expansions to the diameter of the — for lack of a better word — extrusion. This project uses biomimickry to replicate the strength of that design.

The print head is actually four extruders in one. In the clip after the break you can see the black center filament’s rigidity is augmented with three white filaments positioned around it radially. The use of this knowledge? That’s for you to decide. As with some of the most satisfying engineering concepts, this is presented as an art installation. As if the rhythmic movements of that print head weren’t enough, they mounted it on a KUKA and plopped the entire thing down in the center of a room for all to see.

The demo isn’t the only awesome bit. You’ll want to click the link at the top to see the exploded-parts diagram porn found half-way down the page. All is beautiful!

Continue reading “Learning Single-Filament Printing Strength from Arachnids”

Six years, a giant robot, and a kickstarter

robot

Since 2007, [Jamie Mantzel] has been building a huge remote-controlled walking robot. If you’ve been following him on his YouTube channel and blog, you’ve seen the very beginnings of him building a lumber mill to create a workshop, making the legs for his robot, and improving his welding rig. This week, though, has been very special. [Jamie] has finally finished his giant robot project, bidding closed the fevered dream of a madman who awakes to a 10 foot robot in his yard.

The giant robot is constructed nearly entirely out of scrap aluminum. In the interest of simplicity, [Jamie] has come up with some interesting techniques to scale up conventional RC gear to power huge motors swinging giant legs: the steering motors are powered by manual switches, but these switches are activated by servos. A brilliantly simple solution to driving high-current loads if we do say so ourselves.

[Jamie]’s robot has garnered a lot of attention over the years, so much so that toy companies have licensed his designs for a line of battling combat spiderbots. [Jamie] believes his robots should be more educational, so he’s launched a Kickstarter for his own version as a kit. With this kit, getting the bug tank robot up and running isn’t simply a matter of pulling it out of the box and installing batteries; [Jamie]’s version is an actual kit with linkages that must be assembled. We know which version we’d want.

It’s an amazingly impressive project, and we’re glad to see such an awesome cat has finally realized his dream of a walking aluminum arachnid of death.