IMU Boards As Next-gen Motion Capture Suit?

This guy takes a drink and so does the virtual wooden mannequin. Well, its arm takes a drink because that’s all the researchers implemented during this summer project. But the demo really makes us think that suits full of IMU boards are the next generation of motion capture. Not because this is the first time we’ve seen it (the idea has been floating around for a couple of years) but because the sensor chips have gained incredible precision while dropping to bargain basement prices. We can pretty much thank the smartphone industry for that, right?

Check out the test subject’s wrist. That’s an elastic bandage which holds the board in place. There’s another one on this upper arm that is obscured by his shirt sleeve. The two of these are enough to provide accurate position feedback in order to make the virtual model move. In this case the sensor data is streamed to a computer over Bluetooth where a Processing script maps it to the virtual model. But we’ve seen similar 9-axis sensors in projects like this BeagleBone sensor cape. It makes us think it would be easy to have an embedded system like that on the back of a suit which collects data from sensor boards all over the test subject’s body.

Oh who are we kidding? [James Cameron’s] probably already been using this for years.

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Fail Of The Week: The Follies Of A Bootstrapped CNC Mill


Anyone who’s built their own CNC machine from scratch will tell you that it’s no walk in the park. Heck, even commercially available (but hobby priced) 3D printers are no picnic to get running reliably. This offering is the tale of how [Brian Amos] failed at building a CNC mill over and over again. But hey, that ‘over and over again’ part is what makes great hackers. He not only documented what didn’t work, but shows the hacks that he tried using to work through each scrape.

We think the most interesting bits are in his second post, but start with the first one (it’s a quick read) to get the background on the project. The real issues start with a common one: a bed that is severely unlevel compared to the cutting head’s axes. The solution is to use a sacrificial bed, milling it out to match the surface to the tool. This exposed the next issue which is a misaligned Z axis. Some give in the entire support structure means problems with slop and backlash. And there’s even a very creative spiral-cut coupler to help account for alignment issues between the lead screws and motors.

The nice thing about building a mill is that you can turn around a use it to mill more accurate replacement parts. Just keep telling yourself that as you toil away at a project that just won’t seem to work!

We’re already looking for next week’s fail post topic. Help keep the fun rolling by writing about your past failures and sending us a link to the story.

Stompy, The 18-foot, 2-ton Hexapod Is Ready For Production


Over at the Artisan’s Asylum hackerspace in Somerville, MA, something terrifically awesome is happening. They’re building an 18-foot diameter, 2-ton ridable hexapod that can walk over a car. It’s called Project Hexapod and they need your help.

Over the last year or so, the team behind Project Hexapod has developed an amazingly inexpensive hydraulic control system for each of the six legs and created a 1:1 model of the leg fastened to a wheeled cart to get the kinematics down pat. Now, with thousands of pounds of steel already watercut for the legs, they’re turning to the community for a little help with the welding.

The Project Hexapod team estimates they have about 1100 hours of welding time in front of them. They’re looking for a few people around the Boston area that are familiar with steel fabrication and are willing to work on a two-ton robot that can walk over a Volkswagen Beetle.

The guys have put up a little application form if you meet those basic requirements. You can also check out their Facebook page for any announcements and a whole lot of pictures.

Your Hackerspace Needs A Biology Lab; Here’s The Inspiration


When you think of Hackerspaces what pops to mind? For us it’s electronics first, then machining related stuff (3D printing, CNC milling), followed by welding, woodworking, auto mechanical, we could go on and on. But biology hacking doesn’t really make that list. The New York based Genspace is a strong case on why we should add a biology lab as a viable hackerspace option.

What are Hackerspaces other than a collection of tools and skilled members that helps to bring the mad scientists of the world out of their basements and into the light? Pretty much every Hackerspace teaches classes that are open to the public. This is basically a requirement of being a non-profit, but is also driven by the virtue of making knowledge open and available. Offering biology themed classes is an incredible tie-in for helping to see our young learners through to a career in the sciences.

Vice-President and Co-Founder [Daniel Grushkin] was inspired by college students who hack organisms for a one semester long project. He wanted to try his hand at it, but needed help with the resources. He gathered a few others who were interested and, with encouragement from NYC Resistor, they got Genspace up and running in Brooklyn. The organization holds safety as a top priority. Each new member learns about the Biosafety Level 1 guidelines used by the space. For less involved experiments they even use tools of their own making, like a glovebox similar to this one.


Bow Tie Kindly Suggests That You Back Off


Everyone’s had their “personal space bubble” burst. You just wanted a friendly conversation, but now some overzealous blockhead is standing on your shoes and breathing in your face, making you guess what he had for lunch. Fortunately, [Grissini] has created this sylish bowtie solution. Stand too close (within 19 inches) and the LEDs come to life, flashing a warning that indicates a personal space violation. [Grissini’s] tie is 3D printed to accommodate most of the electronics, which snugly snap into place. The rest of the wiring appears to run through the neck strap and connect up to a battery pack hidden elsewhere. You can check out a brief description and demonstration in a video after the break.

We’ve seen this hack for the ladies: [Jeri’s] dress performs a similar function. We’re unsure, however, if these LEDs can deter your average socially-awkward space invader. What we’d really like to see is someone take these hacks to their logical conclusion and make a wearable out of the non-lethal dazzler clone…hopefully the victim would back up a step or two before they spewed.

If you’re lonely and want to encourage people to come closer, maybe this LED bow tie will help. Or, who knows, maybe it’s yet another way to scare people off.

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