This is a neat project indeed. My guess is a small gearmotor, although I can think of a couple of ways to do it using a small motor similar to the vibration motor in a pager. Then a PWM drive to slow it down, and it is done, except if it needs to be checking for movement to tigger the motion.
But this project could indeed be the start of another fad.
He purchased the butterfly as seen in the photos, I'm not sure what the wings are made of but it looks like some fairly thin cloth/nylon/spandex type material. In the Instructable he says that the wings will be finished in fabric that matches the dress.
A moving mechanical butterfly in your hair would really turn some heads. It seems that DelFly is on to something similar although they could use some tips in making their ornithopters more "butterfly" looking. And, of course, remove the camera as well. Getting it to alight on top of the brides hair whilst in the course of reciting her vows would also get a few "wows".
Some of this technology has been perfected and mass marketed in the RC helicopter and airplane world. Minature recievers, lithum ion batteries, tiny servos made from motors and a leadscrew occuping less than 1/2 of a CC. The green led in this case tells the operator that the system is powered and ready. I would have modified a Ready to fly Blade MCX which costs $135 and includes a co-axial 4 channel helicopter, 4 channel radio, battery and charger...
The 100% solar-powered airplane Solar Impulse 2 is prepping for its upcoming flight, becoming the first plane to fly around the world without using fuel. It's able to do so because of above-average performance by all of the technologies that go into it, especially materials.
With major product releases coming from big names like Sony, Microsoft, and Samsung, and big investments by companies like Facebook, 2015 could be the year that virtual reality (VR) and augmented reality (AR) finally pop. Here's take a look back at some of the technologies that got us here (for better and worse).
Good engineering designs are those that work in the real world; bad designs are those that don’t. If we agree to set our egos aside and let the real world be our guide, we can resolve nearly any disagreement.
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