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June 19, 2008

Big Buck Bunny: open source animation

Earlier this year, I wrote about project Apricot, an open source game that is currently under development using Blender and the Crystal Space game engine. This isn't the only project that the Blender Institute has been funding recently. Big Buck Bunny, a completely open source animated film, was released at the end of May. It's an impressive case study for what can now be done on the Blender platform.

This Open movie project had as main targets:
Developing tools in Blender for editing and rendering hair, fur or grass
Improve character animation tools for cartoonish motion and deformation
Test Blender with giant outdoor environments, with large grassy fields and many trees with leaves
Further validate Blender as a professional animation creation suite

And secondary:

Create a great and good looking animation short, licensed freely as open content
Provide content for other artists to learn from or to re-use, including documentation and tutorials

And of course: Have lots of fun!

I recognized a few of the film's characters from some of the demos that have been released in the Apricot game development site. The beauty of open source is that a lot of these assets can be shared between projects. There's also something to be said for a development culture that embraces documentation and information sharing. Take this "bunny rig" character animation control demonstration, for example:

The Blender community has already been really good with program documentation, tutorials and howtos. The development of open source games and films, with all the techniques and artwork that is a part of that process, takes things one step further. Now you also have a chance to learn from the techniques that were used in the making of a larger film project, straight from Blender animation gurus. It's not every day you have an opportunity to download full artwork, scene, and animation assets for an entire film.

Big Buck Bunny
Blender - open source 3D content creation suite
Elephants Dream - the first open movie project, made using Blender

Previously: Open source game development

June 18, 2008

Ugly your bike

I've never been able to get comfortable with locking my bike to a rack and leaving it unattended. If you have a nice ride, no matter how nice of a lock you have, it always seems like you're just asking for someone to rip it off or monkey with it. A bike securely-locked but stripped naked to the frame is someone's really bad day.

The latest trend among bike aficionados here in Minneapolis is camouflage. The tactic is to try and out-ugly everything in sight, making other rides more appealing to the predator. It has the anti-theft advantage of riding a super-crappy, completely undesirable bike, but it's just a facade. In many instances, layers of duct tape, rust stickers, a nasty fender, and crackled paint are hiding a couple thousand dollars worth of high-performance machine.

MAKE Volume 11 had a comprehensive article on the subject, which is available in an online format. The photo above is from the bikehacks site. They've written on the subject a couple of times and have a few useful tips, including an "undo" feature: wrapping the frame in saran wrap before applying stickers and paint.

MAKE V11 - UGLY Your Bike
Ways To Ugly Your Bike
Ugly Your Bike #2: A Case Study

June 17, 2008

Twilight trounced - don't update your Wii until further notice

Nintendo's latest Wii update added a new feature that deletes any doctored Twilight-hack savegames that you have on your Wii. Seriously, Nintendo?

The Wii homebrew channel will still work, though you would need to install the channel before updating (since it requires the Twilight hack during its install process). For Wii homebrewers, the current recommendation would be to hold off on updating until a replacement hack method is made available.

The update contains a very specific addition that prevents this exact hack, so it sets up a bit of an arms race scenario. Someone will soon release a new variation of the hack that will bypass this security check and presumably Nintendo will fire back with another update. It's kind of a bummer, but it's pretty interesting to watch the dissection of this latest obstacle. Wii hackers at their best:

Okay, now this is just silly. Three functions have been added to the system menu. Guess what they do:
ipl::utility::ESMisc::DeleteSavedata((unsigned long long, EGG::Heap*))
ipl::utility::ESMisc::VerifySavedataZD((unsigned long long, EGG::Heap*))
WADCheckSavedataZD

We Are Not Impressed.

You can follow the progress over at hackmii.com. My guess is that a new homebrew method will be available in the next few days.

June 16 Wii update - hackmii.com

June 16, 2008

Controlling stepper motors

I've become so familiar with using standard DC and servo motors for my electronics projects that I've been neglecting a resource that I seem to have an unlimited supply of. There is a mountain of old floppy drives growing in the basement chock full of stepper motors waiting to do a robot's bidding.

The benefit to using stepper motors, besides the abundant availability in all sorts of junk electronics from printers to floppy drives, is that they can be controlled in precise increments. The only downside is that they are a little more complicated to use. For the electronics gurus in the room, controlling a stepper motor is probably old hat. For the rest of us, here are some handy links that'll help you resurrect some old peripheral guts.

Control of Stepping Motors by Douglas Jones
Use disk drive steppers from a parallel port
Tom Igoe's Stepper Motor Control - circuit variations and microcontroller (including Arduino) source
Arduino/Wiring Stepper Library

To use a stepper motor with the Arduino, check out Tom Igoe's documentation (third link). The circuit is straightforward— you'll only need the stepper, your Arduino, and a Darlington array (for unipolar motors). There's an additional tutorial that ties this all together here: Unipolar Stepper Motor Arduino Tutorial.

Go forth, make some cool stuff, and send us a link to your creations.

June 15, 2008

Home security with Twitter and a webcam

Shantanu Goel created a cool home security tool using Twitter and a linux application called Motion, a program that will monitor a webcam looking for differences between frames.

When Motion detects movement, it archives a photo of the event and has the option of triggering an external script. Shantanu combined this with a simple curl command that will ping your Twitter account when a motion event occurs. The end result is a tweet that tells you that motion was detected and checking Motion's integrated mini-http server will allow you to see if it's a false alarm or view the intrusion in real time.

I'm going to set this up at work so I can track down who keeps running off with my red stapler.

Keep Tab On Home Security With A Webcam And Twitter
Motion

June 14, 2008

GasPriceWatch - find cheaper pumps

I really don't drive that much, so when I fill up every month or two, the experience is normally accompanied by equal parts shock and foul language. The strange thing is that the price of gas is always significantly more expensive in the city, and every once in a while, you can happen across a random station that is selling fuel for more than 10 cents a gallon less than everyone else.

It's counter productive to drive all over looking for the cheapest pump, so instead you can use the GasPriceWatch Google Maps mashup to surf pump prices from home. Site visitors report in with updated pump prices, and hopefully there will be a good find along your normal commute route.

Google Maps Mania has a few links to some other maps-related gas tools that you may also be interested in. As for me, I'm sticking to pedaling.

GasPriceWatch
Finding Cheap Gas on Google Maps

June 13, 2008

Milk plastic

Casein, a protein found in milk, can be easily precipitated from standard moo juice with vinegar and turned into a malleable homemade plastic. Coffeebot wrote an Instructable that shows you how:

The final product is quite rigid when it's thick (1/8 inch or thicker), moderately pliable when it's a little thinner, and brittle if it's paper thin. It's also sandable and paintable.

I guess casein-based plastics used to be all the rage for buttons, jewelry and pens at the beginning of the 20th century.

Homemade Plastic From Milk [via MAKE]

June 12, 2008

HOWTO - scrub private data from your iPhone

Jonathan Zdziarski, author of iPhone Open Application Development, has been working on a forensics toolkit for law enforcement that allows the recovery of personal data from the iPhone. Apparently, the inspiration for this came from a discovery that refurbished iPhones, straight from the Apple store, often times contained personal information on the reformatted filesystem. This includes things like photos, contacts, and even more personal information that might have been in an email.

Just as you would scrub a hard disk before selling your computer, you should take a few minutes to clean the data from your iPhone if you're thinking of getting rid of it. Performing a normal restore just recreates the filesystem without completely scrubbing the drive's data, so to really clean a device before getting rid of it, you'll need to completely write over the disk. Jonathan has an article which walks you through a few simple steps to do just that. Writing over the entire disk takes quite a bit of time, so be prepared to let it sit for a couple of hours.

Making your iPhone Safe for Resale

June 11, 2008

YBox2 - a networked set-top box

The original YBox was a nifty little electronic gewgaw that made it easy to make a network appliance that displayed itself on a TV, all fit into an Altoids tin. The kits have been sold out for quite a while, but I'm excited to hear that it's been given a second life in the YBox2 platform.

Robert Quattlebaum undertook the task of creating the new version and teamed up with ladyada to help bring the new kits to the hacker masses. It's built around an 80MHz 32KB Propeller chip, supports NTSC and PAL, and comes prepackaged with a bootloader that allows you to upload new firmware over ethernet instead of requiring you to use a programmer cable.

This is an open hardware project, so you can either build it from scratch or purchase a kit from the adafruit store. All you'll need to do after that is write a cool widget for it and send an email my way so I can post it here. :)

YBox2 - DIY Networked Set-top Box

June 10, 2008

Free magazines for iPhone users (and fakers)

If you have an iPhone, or the handy User Agent Switcher for Firefox, there are a couple of sites that offer free digital versions of several popular magazines. I guess the idea is to try and capture email addresses, but you can cancel through the input boxes and get straight to the content fairly easily.

If you are using Firefox, you can fake your browser into reporting itself to web servers as an iPhone by downloading User Agent Switcher and adding an "iPhone" entry with the following user agent string under Tools->User Agent Switcher->Options:

Mozilla/5.0 (iPhone; U; CPU like Mac OS X; en) AppleWebKit/420.1 (KHTML, like Gecko) Version/3.0 Mobile/4A102 Safari/419 (United States)

Once you've switched to that user agent profile, most sites will think you are browsing from the iPhone platform and display the content that is targeted to that device - in this case, free magazines. The two sites that provide magazine content targeted to the iPhone are:

I should mention that there are a couple of racier magazines to be found in there, so I'll stamp this one with a potential NSFW factor. I'm sure you were going to just scroll right past and check out the Reader's Digest anyway, so it's probably not worth mentioning.

[via LifeHacker and Geek.Phatus.com]

June 9, 2008

Time lapse movies using a graphing caclulator

If you want to shoot time lapse movies with your DSLR, you need an intervalometer, a simple device which sends a signal to your camera to trigger the shutter at a timed interval. You can buy one for around $100, or you can write a few lines of basic and have your trusty TI calculator take timed photos for you, resulting in nifty movies like this:

Yonderknight has an Instructable for doing exactly this with a standard TI 83. You can connect a Canon EOS Rebel to the calculator with the standard 2.5mm data link socket, and the software just sends a 1 down the line once a second. Matt Coneybeare tool this a step further with his code for the TI-89, allowing the user to specify a duration and interval period.

Both howtos walk you through the whole process, including a couple of recommendations for importing and converting the image frames into a video. It should be pretty straightforward to adapt either of these methods to your specific TI platform and video needs.

Turn a TI-83 into an intervalometer
Time-lapse code for the TI-89

June 8, 2008

Star Wars music played by a floppy drive

I can't find any documentation for this, nor can I help posting it.

I assume it's a hardware hack that manually controls the floppy drive's stepper motor, but it'd make my day if this was done in software using standard I/O requests. Either way, the 3.5 inch FDD finally serves an important function again.

Star Wars Floppy Disk

June 7, 2008

Turn a Brita filter into a reusable activated carbon filter

We filter our drinking water at home, though it's not because there's a risk of giardia or heavy metals in the tap water where we live. Personally, I just like the taste of water that's been run through activated carbon. If your own water is safe from heavy metals, but you still like the way water tastes when it's been through something like a Britta filter, there's an easy way to convert the filter to be reusable, saving a ton of waste and a bit of money.

Your standard Brita pitcher filter contains two components, an ion exchange resin that is used to reduce heavy metals, and a bunch of activated carbon which is used to remove chlorine and various organic impurities that can affect the water's quality and taste. I'm not sure about how to go about recharging or replacing the ion exchange resin, but activated carbon is available in any pet store, where it is sold for aquarium water filtration.

Below is a link to an Instructable which shows you how to convert a Brita pitcher filter into a refillable carbon filter. You'll only need a couple standard tools to do the conversion, and when it's complete you'll have great tasting water, you'll be able to do refills for about 50 cents a cartridge, and you won't be tossing a one-time-use hunk of plastic in the landfill.

Refill A "Disposable" Brita Water Filter With Activated Carbon

June 6, 2008

Electronic embroidery

I'm told that one of the most popular projects at the CRAFT table at Maker Faire is our friend Becky Stern's electronic embroidery. If you're into crafting, all it takes is a little conductive thread and you can make your own fabric gadgets.

Becky posted an introduction to electronic embroidery on the CRAFT blog today and I think I just learned how to backstitch. Her introduction shows how to wire up a couple of LEDs and a switch, but there are a lot of directions to take this. Of particular interest is the LilyPad, a tiny sewable Arduino board that's about the size of a half dollar. There are also various sensors designed around this platform, including sew-friendly accelerometers. There must be a good running jacket idea in there somewhere.

Electronic Embroidery - CRAFT Video Podcast
Conductive Thread and LilyPad Components at SparkFun

June 5, 2008

DIY Slingbox

Using a standard DV cam, a Mac Mini, and the Quicktime Broadcaster utility, you can roll your own Slingbox-style TV streamer on the cheap. David Glover, realizing that his DV camera had an analog input and firewire output, put together a howto for doing just this:

Yesterday from a dusty shelf I discovered my Sony DV camera. And after playing with it for a while I discovered (or possibly re-discovered, as I might have just forgotten) that it has analogue video inputs that it will digitise and then spit out of the DV port.
So this gave me an idea - this is essentially what the Slingbox does, except the Slingbox outputs a network stream rather than DV video. But I have a Mac Mini sitting underneath my TV downstairs, and that has a DV port on it...

This is really handy if you want to catch a show on your computer while you are working from another room. Assuming you also have a DV camera and a spare Mac you can connect to your TV, it's also essentially free.

DIY Slingbox
QuickTime Broadcaster - Apple's free video transcoder and streaming utility

June 4, 2008

Use video RAM as swap in Linux

If you are into the headless or console experience, there are a couple of ways to put your machine's graphics card to good use. Most new boxes come with a GPU that has a substantial amount of RAM that is normally used for direct rendering. Using the Memory Technology Device (MTD) support in the Linux kernel, you can actually map the video card RAM to a block device and format it for swap use or as a ramdisk.

The Gentoo wiki has detailed instructions for doing this. The only tricky part is determining the video memory address, but after that it's a simple modprobe to load the MTD driver and you can run mkswap/swapon on the device just as if you were creating a normal swap disk. Considering many machines have 512MB of video RAM and it's waaaaay faster than disk, this could give you a pretty huge performance boost.

You can still use your graphics card in X, but you'll need to reserve a small chunk of that RAM for normal graphics use, use the VESA driver, and add inform the driver that it should only use that teensy portion of memory. "VideoRam 4096" in the XF86Config, for instance, will let you use your card in X and only eat the first 4MB of RAM. Everything after that 4MB is fair game for swap. Michal Schulz wrote a bit about calculating the memory address offsets to make this all work. It's the second link below, for those of you who aren't hardcore enough to deal with only the command line.

Use Memory On Video Card As Swap
Configuring X11 With A VRAM Storage Device

June 3, 2008

Google Earth has a Javascript API

Google released a plug-in, currently for Windows browsers only, that allows you to embed the Earth application inside the browser. Existing Google Maps mashups can use some of the functionality right away just by adding the G_SATELLITE_3D_MAP map type. Even more exciting is that you can interact more deeply with the map—including camera angles, KML layers, and 3D models—right from Javascript. I'm so eager to go find a PC to play around with this that I'll let the video speak for itself.

Also worth noting is that Google just released an official Maps API for Flash AS3. Call me a fanboy, but I think my head is spinning.

Google Earth API
Some Example Applications
Maps API for Flash

June 2, 2008

Wii Guitar Hero guitar as a real musical instrument

I've been trying to get better at Guitar Hero and I'm bothered by the fact that you dump so much time into learning a basically useless combination of finger twiddling tactics. At least with DDR you get some exercise, and other video games let you drive fast or kill things. Of course, I say this only because I completely fail at Guitar Hero and I'm jealous of everyone who was born with the appropriate twiddling genes that let you get past the easy level. Back to my point, though, wouldn't it be great if those gaming hours could be spent actually learning to play an instrument?

Josh Breckman posted the above video to Youtube a while ago and has gained quite a bit of notoriety for his hack that turns the Wii Guitar Hero controller into a real instrument. You don't play it like a legit guitar, of course, but by adjusting the tilt of the guitar and flexing the whammy bar, the 5 buttons can be used to toggle a variety of notes and effects.

Anyway, it turns out we get all 5 button states (obviously), up strokes and down strokes (separately), and 11 degrees of movement of the whammy bar.
I took this info and fed it into my handy synthesizer as I played and turned it into a sort of instrument. My keyboard has a pretty decent electric guitar sound, so it sounded sort of realistic. I used the wiimote's orientation and the whammy bar to add different "note banks" to let me play more than 5 notes.

I assume this is using a custom GlovePIE script to funnel commands to the software that's controlling the synth, but I don't really know much more about it than that. Josh says he'll be posting a tutorial soon. Until then, I'll be stabbing buttons while colored dots fly at me in three dimensions.

Wii Guitar Hero Synth Hack

June 1, 2008

AVR tri-color LED controller

A little while ago we posted about a fun LED scroller project made by Hackszine pal Kalanda. He wrote in today with an update about his latest howto project, a multi-color animated LED controller based on the AVR platform.

The new project based in AVR microcontrollers Its an "Habitat Mirror Hack" with RGB Leds (superflux). Its the Peggy Muppets Mirror.
I replace the regular bulbs that it has, with superflux RGB leds and i make a controller based on ATMEGA8 for control 16 rgb leds with 3 bits of color depth (8 colors). In my post you can download scheme, pcb and source code.

It looks like a fun project, and you could adapt it for other uses pretty easily. His site is in Spanish, and though I'd normally like to a Google Translate version, unfortunately Translate isn't converting the entire post, only the first paragraph. To get the full details, you'll have to cut and paste the text into Translate manually.

Thanks, Kalanda!

Kalanda's RGB Mirror: an AVR tri-color LED controller

May 31, 2008

Create a macro lens from an old 50mm

Lambert Smith has a great howto for converting a standard 50mm lens from an old SLR camera into a dedicated macro lens for your digital camera. By reversing the 50mm lens and using a number of extension tubes. The photo above is his conversion hack on a Canon Powershot G3, which has a non-interchangeable zoom lens. Custom adapters can be made by gluing filter rings back to back, so you can do this with a normal digital, a DSLR, or even a traditional film camera.

Once set up in this manner, your camera will have a fixed point of focus (unless you use a bellows). When taking a photo, you simply move the whole camera toward or away from the subject until it is in focus.

Reversed 50mm - A Dedicated Macro Lens