Laser triggered photography


Popped balloons or bullets fired into apples, anyone can photograph with a quick sound based camera rig. Lasers have been used forever in motion detection. And even door bell chimes have been used before for remote camera shutter releases. No, [SaskView] wanted to go further and created his Laser Triggered High-Speed Photography setup, to photograph (of all things) milk splashes. We liked the simplicity of the project however;  requiring no programmed microchips or overly complicated circuitry – rather he took a quick trip to the local dollar shop, used the amazing CHDK firmware, and he produced perfect results every time.

[Update: CHDK, not CHKD firmware. My mind must be elsewhere. Thanks jbot and agent smith]

Life size animatronic wolf tail


We’re not 100% sure the usefulness of this hack, but it is extremely interesting regardless and will probably make a lot of furries happy. WolfTronix presents their method for creating a realistic animatronic wolf tail. It uses an Atmel MCU controlling two servos alongside a mess of Klixx toys and paper clips to produce a nice wag motion. The guide is extremely detailed and looks to be fun, so long as you don’t mind the monotonous task of shaving off potentially hundreds of ‘nubs’ as they call them. Either way, you’ll definitely have the best (and only…) tail on the block.

Thanks [J. Peterson]

Subwoofer makes cornstarch dance

People tend not to think about the non-Newtonian properties of foodstuffs, but we’re glad at least one person did. When it comes to cornstarch, it’s indeterminate viscosity when mixed with water made it the perfect solution for a pretty neat trick: making a liquid move in reaction to a subwoofer. The unique motion can be attributed to the physical properties of the solution: when enough force is applied quickly, it acts as a solid. Otherwise, it flows like a liquid. The erratic bouncing of the sound waves combined with a little tactile manipulation create varying degrees and speeds of applied pressure, which in turn create a mass of flowing shapes that almost appear to be alive.

We’ve covered weird fluids before, but this is perhaps most similar to SnOil, a game that uses ferrofluids to achieve a similar result. SnOil, however, does not depend of vibrations to create shapes in the fluid, it uses small electromagnets and magnetically charges liquid instead. We love the ordered appearance of the SnOil unit, but the chaotic motion of the cornstarch and it’s non-Newtonian properties make it appear almost otherworldly. We wonder how ferrofluids would react in a situation similar to the cornstarch above, since it would respond to both the vibration and the voice coil’s magnetic field.

[via Neatorama]

More Wiimote hacking from Johnny Lee

Our friend [Johnny Lee] has been quite busy traveling and moving to a new city. He hasn’t had time to put together any new videos because of this. He’s been doing more Wiimote research though and has put together an extensive post about what he’s working on and thinking about.

Right before the move, he put together a demo for throwable displays. The square pieces of foamcore have retro-reflective tape added to each of the corners. The Wiimote sees the orientation of the square and adjusts the projected image to fit perfectly; even when you pick it up and throw it. He used it to add a trail to an airhockey puck. Embedded above is an earlier project where he used the Wiimote to track a foldable display and project accordingly.

[Johnny] has also been working on 3D tracking with two or more Wiimotes. Since the Wiimote is camera based, stereo triangulation is simple. Check out the video below from the University of Cambridge that uses two Wiimotes for motion capture.

Have a look at [Johnny Lee]’s full post for even more Wiimote ideas.

Twitter security cam

It seems that people keep coming up with ingenious things to with Twitter. Reminding you to water your plants is relatively inventive, but for shear practicality, [Shantanu Goel] created a security camera using a webcam, a few freeware apps, and a Twitter account.

To make this work, install Motion on a system running Linux. As its name suggests, Motion is a free motion-detecting application that monitors movement in a webcam’s field of view. Once installed, it should be configured to take a snapshot of the event whenever something moves; with the locate option turned on, it draws a square frame around the area where motion occurred. The program includes http server functionality, so the photos can be viewed from a remote location. When all of that is properly configured, motion can be set to trigger cURL, Wget, or [Goel]’s Perl script to post a message to Twitter about the event. From there the Twitter account can be configured to send text messages to a phone, creating a virtually instant notification of motion sensed by the webcam.

[via Hackszine]