[ElectricSlim] likes taking “Jump Shots” – photographs where the subject is captured in midair. He’s created a novel method to catch the perfect moment with OpenCV and Processing. Anyone who has tried jump shot photography can tell you how frustrating it is. Even with an experienced photographer at the shutter, shots are as likely to miss that perfect moment as they are to catch it. This is even harder when you’re trying to take jump shots solo. Wireless shutter releases can work, but unless you have a DSLR, shutter lag can cause you to miss the mark.
[ElectricSlim] decided to put his programming skills to work on the problem. He wrote a Processing sketch using the OpenCV library. The sketch has a relatively simple logic path: “IF a face is detected within a bounding box AND the face is dropping in height THEN snap a picture” The system isn’t perfect, A person must be looking directly at the camera for the photo the face to be detected. However, it’s good enough to take some great shots. The software is also repeatable enough to make animations of various jump shots, as seen in [ElectricSlim’s] video.
We think this would be a great starting point for a trigger system. Use a webcam to determine when to shoot a picture. When the conditions pass, a trigger could be sent to a DSLR, resulting in a much higher quality frame than what most webcams can produce.
Continue reading “Perfect Jump Shots with OpenCV and Processing”
Looking for a light project to teach young hackers some very basic electronics? Here’s a quick and easy weekend project, a simple metal detector!
We all know 555 timers are very useful and pop up in a wide range of projects, but did you know a metal detector is one of them? [vonPongrac] stumbled upon this handy guide, a free eBook on 50 555 Circuits, which contains many cool project ideas, including a simple metal detector circuit. It’s a very basic concept that uses a coil of copper wire as a home-made choke — when metal or a magnet comes near the coil, it varies the output frequency, and the 555 timer in turn, varies the output sound, alerting you of the presence of something metal nearby.
After the break there’s a video of it during its testing phases. If you don’t have a 555 on hand (tisk tisk) but still want to have some treasure hunting fun you can also build one based on an Arduino.
Continue reading “DIY Metal Detector”
Although Dogs and other animals love to mark their territory with urine, this technique has been generally ignored by human beings. Despair no more, fellow homo sapiens, we have now developed the ability to check-in on foursquare through your information stream. This device is descriptively called “Mark your Territory.”
Although this is not currently available to buy in stores (although apparently $10,000 will get you one built), [Instructables] user [blorgggggg] has furnished directions on building your own. The system is powered by an Arduino and an Android phone. The urine tags have both a pointed end for sticking in grass and the like, and a sticky back to be used in a “more urban settings.”
The video after the break gives quite a bit of background trying to justify such a system in terms of communicating in the physical world, animals, et cetera, but it’s doubtful that this excuse will get you out of a public urination charge. You’ve been warned.
Ever wish you could DJ on the fly while using equipment that your already wearing? Well neither have we but heck now we can, cheaply and easily with the Wristwatch Turntables. While being functional and stylish, this interesting project is fairly easy to construct and if need be, even sports a full function digital watch.
The audio electronics are donated by a pair of talking / musical greeting cards. Both, “record your own” and “just deal with what we give you” types, though which ones you choose is left up to your taste. The greeting cards are then cut apart for their hidden goodies and then a little circuit bending action is performed to monkey with the amplifier of the sound module.
Potentiometers are added, buttons are relocated, and everything gets housed in a small box, with a wristwatch ran down the middle so you can wear the whole deal and blast your funky beats anywhere you may be. Join us after the break for a quick video.
Continue reading “Wristwatch Turntables”
New Project Hosting site
[Paul] wrote in to tell us about his brand new hack hosting service, HackHut. Based on WordPress with some modifications, it is definitely worth keeping an eye on as new features emerge.
Speaking of project hosting, Instructables are a common source of projects as well as complaints. Instructabliss by [Daid] is an often mentioned solution in our comments, and we thought we would bring it up so commenters don’t have to. We understand why it was made and think it was a clever hack, but we don’t officially endorse it. We survive on Ad revenue, if someone were doing this to us, it would hurt. We’re also not sure about the legalities of such a service, so keep us updated.
Grass Burning Robot
[Sebastian] brings us his grass burning, flame throwing robot. This robot takes in SVG files to create its burn path, and burns away. Not too many details, but be sure to check out the photos on his site.
We got a pleasant letter from [Eric Willhelm], the owner of Instructables. He wanted to shoot a token of good will our direction, in the form of an EPUB of some of the projects we’ve linked to in the last quarter of 2010. These are Ad-free and have all images included. You can download it and view it on the e-reader of your choice, or even in your browser with the appropriate plugin. The videos still link back to Instructables, but he thought our readership might enjoy having an ad-free experience. He says that link should work for about a month.
For those who really want ad free content and are willing to pay for it, Instructables has been putting out publications that are collections of instructables on certain topics. For example, [Eric] pointed out that they’ve compiled some that might be of interest to us like “Better living through microcontrollers” and “Amazing LED Projects“. Actually, there are a bunch of titles and it looks like some are free as well.
Thanks [Eric], I’m sure your actions gained a little respect, even from those who dislike Instructables generally due to ads and registration.
If you follow Instructables.com, it might seem like every third article lately is about Sugru, the nifty air-drying silicone putty that’s good for all manner of repairs and custom parts. It’s fantastic stuff (and we love their slogan, “Hack things better”), but one can’t (yet!) just drop in on any local hardware store to buy a quick fix…so [mikey77] has cooked up a recipe for a basic Sugru work-alike. His “Oogoo” (a name likely inspired by oobleck) is a simple mix of corn starch and silicone caulk.
A two-ingredient recipe would hardly seem adequate material for an article, but [mikey77]’s left no stone unturned, providing an extensive tutorial not only on mixing the compound, but how to add colors, cast and carve custom shapes, and how his home-made recipe compares to the name brand product. As a bonus, the article then drifts into a little Halloween project where he demonstrates etching conductive cloth, how to make conductive glue, and other hands-on shenanigans.