Quick and easy wildlife camera

This wildlife camera is really easy to put together. You should keep it in mind if you’re ever tying to figure out what’s eating the heads off of all of your tulips. [Revoltlab] put it together, and although there’s one fatal flaw in this particular system, the concept is quite sound.

The build uses a camera, paired with an ultrasonic range finder. When something passes within the pre-set distance for the sensor, a servo motor clicks the shutter button on the camera. It’s all driven by an Arduino and powered from a 9V battery.

If you watch the video after the break you’ll discover the flaw we mentioned. This is a disposable film camera and requires winding between pictures. That hasn’t been implemented yet. But we’ve got an old digital camera with a broken LCD screen which would be perfect for the job. We’d have to do a bit more work to turn the camera on before taking the picture though.

There are a couple of possible upgrades to the idea. [Revoltlab] mentions removing the IR filter from the camera and adding an infrared flash for night-vision shots. But we would also recommend ditching the servo motor for a simple remote shutter solution as a way to avoid scaring the wildlife with the motor noise.

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3D whiteboard without the whiteboard

This one is so simple, and works so well, we’d call it a hoax if April 1st hadn’t already passed us by. But we’re confident that what [William Myers] and [Guo Jie Chin] came up with exists, and we want one of our own. The project is a method of drawing in 3 dimensions using ultrasonic sensors.

They call it 3D Paint, and that’s fitting since the software interface is much like the original MS Paint. It can show you the movements of the stylus in three axes, but it can also assemble an anaglyph — the kind of 3D that uses those red and blue filter glasses — so that the artists can see the 3D rendering as it is being drawn.

The hardware depends on a trio of sensors and a stylus that are all controlled by an ATmega644. That’s it for hardware (to be fair, there are a few trivial amplifier circuits too), making this an incredibly affordable setup. The real work, and the reason the input is so smooth and accurate, comes in the MATLAB code which does the trilateration. If you like to get elbow deep in the math the article linked above has plenty to interest you. If you’re more of a visual learner just skip down after the break for the demo video.

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Investigating parking assist sensors

While his wife was out-of-town [James] jumped at the opportunity to do some snooping around with her Chevy Tahoe’s parking assist sensors. We can understand how pulling parts out of someone’s car would make them none too happy. But we find it hilarious that it’s a leased company car he’s tinkering around with. But we’re glad he did, the ten-page write-up he published about the project is a fascinating read.

You can see the control board above which is housed beneath the passenger seat. It uses a Freescale microcontroller to read from the four bumper-mounted ultrasonic sensors. But just looking at what parts are used obviously isn’t enough to satisfy a hacker’s appetite for knowledge. [James] busted out a CAN bus tool to sniff the data packets. These sensors use a custom chip designed by GM, utilizing a single wire communications system. He figures out the communication scheme and builds an mbed based test rig to read them directly.

[via Dangerous Prototypes]