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June 26, 2008

Flight instruments for an RC plane

There are products available that will overlay flight data into a flight camera's video stream, but here's a clever and simple hack to do it on the cheap(er). To provide in-video flight data for a first person view aircraft, just build a mini flight instrument panel and position it in front of the camera.

One of the main problem with FPV is that you can get lost very, very easily. We are not really used to know our environment from a bird's eye view!
Here is one solution to find your way back home:
The device below includes a GPS receiver and a microcontroller (it's inside the blue heatshrink sleeve) grabs interesting data like latitude, longitude, altitude and speed from the NMEA sentences, calculates bearing to destination (the pilot) and displays relevant data to the "instruments" (micro servos with a needle!)

On the left: speed, in km/h
In the middle: bearing to destination - if the needle is vertical, you're on the way back home!
On the right: altitude, in meters (divided by 10)

This is something you could easily build yourself and you'd be able to add any features you wish. I'm thinking a data logging feature would be cool. That, or a geo-targeted pingpong ball deployer.

Aircraft Panel For First Person View

June 25, 2008

Image Fulgurator - subverting other people's photos

Berlin hacker Julius von Bismarck invented and patented the Image Fulgurator, a device so awesome that it can remotely insert images into other people's photos.

You aim the device at the same subject that another person is photographing, and when they snap a photo the resulting image will be manipulated with a separate, overlayed photo. The person taking the photo will have no idea anything happened until they examine their photo.

The result is pure magic. Here's a clip of the first public "image fulguration".

The device uses a standard 35mm camera body and lens as a projector. Instead of undeveloped film, the camera is loaded with exposed, developed slide film. A flash is built into the back of the camera, sending light backwards through the body, past the the slide and out the telephoto lens. A light sensor is used to trigger the flash when another camera's flash goes off. Thus, when someone else takes a photo, the Fulgurator zaps its slide's image onto the object for a few milliseconds.

In you want to make something like this, you can use some of the techniques that folks typically use to photograph lightning. Below is a link to a simple Arduino project that will give your SLR a light activated shutter release.

While you're at it, take a crack at making your own Fulgurator with a bit more stealth factor. I'm pretty sure I'd get tazed walking around downtown waving this thing around.

It'd almost be worth it.

Image Fulgurator by Julius von Bismarck [via The Future is Awesome]
Lightning Trigger for a Camera

June 24, 2008

Videos from past Shmoocons

You may have dug the videos of past DEFCON conferences that we posted back in May, but there's a whole other infosec conference, Shmoocon, which is held in D.C. every February.

ShmooCon is an annual East coast hacker convention hell-bent on offering three days of an interesting atmosphere for demonstrating technology exploitation, inventive software & hardware solutions, and open discussions of critical infosec issues.

It's a while until the next conference comes up, but there have been some great presentations at past conferences, most of which are available online. Peteris Krumins recently assembled links to all of the videos and presentation files that are available at the Shmoocon site (including the 2008 conference), posting them to his blog as a single big index.

A quick search on YouTube also turned up a series of videos by Scott Moulton from Shmoocon 2007 and 2008 on the topic of data recovery for both traditional hard disks and flash drives. It's pretty fascinating stuff, whether you're interested in this from a forensics or security perspective, or if you've ever just wondered what exactly goes into recovering important data from a crashed disk when you send it out to a data recovery shop.

Hacking Videos from Shmoocon
Scott Moulton's videos on data recovery for SSD flash drives and hard disks
Shmoocon Infosec Conference

Algorithm Geeks

If you've ever stumbled into a tricky coding or data representation problem, chances are good that someone has already figured it out. Usually the resolution is found by speaking with the Google, emailing your resident alpha-geek, or consulting Knuth's Art of Computer Programming (you know, the 50 pound box set that's been waiting patiently on your shelf for exactly this moment).

I stumbled across a fourth option this afternoon: the Algorithm Geeks user group. It's an easy way to parallelize your problem, running it past the brains of hundreds of alphas from around the world. Even if you aren't seeking help, maybe there's a post or two in there that you can contribute to. My inner nerd is probably showing, but it's pretty fun just reading through the posts and weighing the different proposed solutions.

Hack on!

Algorithm Geeks Google Group

How we made Google Apps Hacks

When Philipp Lenssen started writing Google Apps Hacks, we made up our minds that we'd develop the book in Google Docs. A while back, Philipp wrote up Part I of the story of how we made the book. From Writing a Book in Google Docs:

Currently, my editor Brian Jepson and I are collaboratively writing the book (tentatively titled) Google Office Hacks by O'Reilly using Google Docs. I wanted to outline the process we came up with, and maybe it's helpful for you too for certain needs.

I just wrote Part II of this story, and Philipp's posted it to the Google Blogoscoped blog. From From Google Docs to InDesign:

One of the tricky parts for us was getting the chapters into InDesign, the book layout program we use for our books and magazines. I know where we were coming from - Google Docs' HTML format - and where we were going to - InDesign's tagged text format.

From the Maker Shed:

Google Apps Hacks by Philipp Lenssen - all about Google Docs & Spreadsheets, Gmail, Google Calendar, Google Presentations, and more!
Price: $29.99
Buy it in the Maker Shed

June 22, 2008

Parallax scrolling in jQuery

Wynn Netherland wrote a plugin for jQuery that makes it easy to add a slick Parallax effect to a web site. For anyone who missed video games of the 80s, this is the old sidescroller technique that simulates depth by making things in the foreground move faster than the background. The jQuery Parallax plugin does this by easing the background position across several div layers, all at different rates.

To make it work, you just make a horizontally tile-able background image, and a horizontally tile-able alpha-transparent PNG for each foreground layer. These are each set as the background image of a separate div with the repeat-x attribute. The divs are absolutely positioned right on top of each other, and then a single line of jQuery code is used to set the animation speed for each layer.

It's a subtle and bandwidth friendly way to add a bit of visual polish to your site. Netherland is using this effect for his blog's masthead, and it looks pretty cool.

jQuery Parallax Scrolling (download)
jQuery
jQuery Easing library - you'll need this too

June 21, 2008

Twilight Hack for Wii v3.3

It's a good day for Wii homebrewers. The latest version of the Twilight Hack was released, fixing the problem Nintendo created with the Wii 3.3 fireware update. A quick turnaround time on this one:

Changelog for this release:
The Twilight Hack is now compatible with version 3.3 of the Wii System Menu.
Improvements in video configuration. The entire console should now be visible in all video modes, and scrolling has been improved.
For the USA version, the two variants of the hack have been packed into one save file. Just select the save slot that corresponds to your version of Twilight Pricess when you start the game.
New savegame icons by drmr. The new icons now show which region that version of the hack is for.
This version now tries to load boot.dol, and falls back to boot.elf if boot.dol is not found.
???????
Many, many bug fixes.

I think the "???????" refers to a little rhyme that is now embedded in the loader file. Here's a snippet:

Now these quick hack fixes have some beautiful holes, So we found them fast and easily met our goals. And I'm glad we got burned. Think of all the things we learned. For the people whose Wiis want new life! Go ahead and patch it. I think I'd like to have some fun. Maybe you'll find an undisclosed bug. Maybe that huge one.

Sounds a bit like a burn.

Twilight Hack v0.1beta1 (download)
How Nintendo's patch was exploited

June 20, 2008

Milkscanner - 3D scanning with LEGO and milk

Friedrich Kirschner's Milkscanner is a clever method for scanning 3D objects using only a webcam, some milk, and a camera rig made out of LEGO.

The basic idea is this: you place an object in a container, incrementally fill the container with milk, and take a photo after each tiny fill increment. The Milkscanner software mattes out the white part of the images, resulting in a silhouette "slice" of the object for each increment in the Z dimension. Each slice gives you information about the outer perimeter of the object at that depth (assuming the object is convex).

Milkscanner is able to output a depthmap from this information which you can use in Blender or MovieSandbox, an open source machinima filmmaking tool. Friedrich has been using the latter to produce some pretty fantastic work. Instead of small objects, however, he was able to scan a human using a bathtub which was filled with ink-tinted water.

The original version is written in C# and requires a Windows PC with the latest DirectX. If I read things correctly, there is a new version that will be released soon which is written using a cross platform drawing and image capture API. Hopefully this means that the new release will be available for Linux and OS X. Fingers crossed - this looks like fun.

Fluidscanner
Milkscanner binary and source downloads (distributed with MovieSandbox)

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