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Cool video

Cool video

Cool video

(OP)
Link

KootK - hopefully, you will see this. I found this video from the same guy who had the tension instability video.

As I commented on the video, it seems if you add rotational stiffness to the rollers, it you could build up potential elastic torsional energy in the bar that would propel the bar at an even greater acceleration than the demonstration in the video shows. Like a modern and more compact catapult...or dare I say gun.

"It is imperative Cunth doesn't get his hands on those codes."

RE: Cool video

Interesting way to use stored strain energy in the steel bar.

BA

RE: Cool video

All about that potential energy baby! Even basic virtual work still feels like magic to me most of the time.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: Cool video

(OP)
I am curious how powerful you could make one of these launchers that is still small enough to hold with two hands. 20 years ago, we used to build potato launchers with pvc pipe; they were barely small enough to operate with one person. Kidz in the future will be using these "elastic energy guns". I am trademarking that name, so don't bother... tongue

"It is imperative Cunth doesn't get his hands on those codes."

RE: Cool video

That's how the counterbalance springs in my house windows work. Freakin' pain to wind them up to support the window correctly. Too much is just as irritating as too little. Fortunately there is enough friction in the frame to expand the window of useful preload.

RE: Cool video

(OP)
I kind of figured this mechanical system already exists somewhere. I wouldn't have guessed windows.

"It is imperative Cunth doesn't get his hands on those codes."

RE: Cool video

Having now watched the second video:

1. I'm still not sure what an "Eshelby Like force" is.
2. Where does this force come from? Does it require the tangent to the contact point to be non-vertical, hence the need for non-tight fit?

Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/

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