Very intriguing! I suppose there is a lot to be discovered about the=20
physical properties of the filler and the bag (bladder?)
It looks like it might scale well for tiny to large items.

First thoughts for testing in my lab:
     probably need a fabric filter to keep the media in the bag and out=20
of the vacuum source. Silk is a candidate.
     Have balloons & some electrically controlled valving from=20
Automotive emission experiments.
     Cannot completely close off airflow for a house hold vacuum=20
cleaner, it will heat to self destruct.
     Wood shop dust collector might have enough for testing.
     Stiffeners in or on the surface of the bag might allow testing with=20
fluids (or mixtures) rather than solid media.
     Pressure controlled stiffeners might be used to shape the grip.

I think it would be beneficial to all to report back here with any=20
successes or failures to implement this concept!

John Ferrell W8CCW

"The same prudence which in private life would forbid our paying our own=20
money for unexplained projects, forbids it in the dispensation of the=20
public moneys." --Thomas Jefferson


On 10/26/2010 10:19 PM, RussellMc wrote:
> Ken says:
>
> It's not actually a new idea.  Many years ago (I think when I was
> still at school) [ say 30+ years] I saw an article in a magazine
> (Popular Mechanics ?) describing a vice for holding irregularly-shaped
> objects based on this exact principle using a football bladder filled
> with sand to which a vacuum could be applied.  I can't remember
> whether it was a comercial product or a construction project.
>
> The major limitation that I see would be the durability of the "skin"
> and the likelihood that the filling would over time tend to break down
> and become less effective.
>
> I wonder if they tried full-cream milk powder.  My extensive
> experience in handling it (including a lot of work with high-speed
> vacuum de-aeration) is that it would potentially be even better than
> ground coffee as the particles are quite a bit smaller yet it locks up
> solid under vacuum.  You'd need to be careful to control humidity
> though.
>
>> http://www.gizmag.com/universal-robotic-gripper/16729/?utm_source=3DGizm=
ag+Subscribers&utm_campaign=3D49751b08ae-UA-2235360-4&utm_medium=3Demail
--=20
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