Helicopter challenge rings

Stand-up rings you can try to knock over or pick up with a remote-control helicopter toy.

MakerHome Day 75: http://makerhome.blogspot.com/2013/11/day-75-helicopter-challenge-rings.html

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#####Twitter: [twitter.com/mathgrrl](https://twitter.com/mathgrrl)

#####Hacktastic blog: [www.mathgrrl.com/hacktastic](http://www.mathgrrl.com/hacktastic)

#####Shapeways geekhaus store: [www.shapeways.com/shops/mathgrrl](https://www.shapeways.com/shops/mathgrrl)

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