🚀 go-pugleaf

In article <BxxsAw.Kq7@aplcenmp.apl.jhu.edu>, doherty@aplcenmp.apl.jhu.edu (Kevin Doherty) writes...
>esm40@cd.amdahl.com (Ed McGettigan) writes:
> 
>>Does anyone know of any materials/liquids that harden when you apply
>>a voltage/current to them and revert when you turn it off?
> 
>  Think there's a whole family of such materials-called (I believe)
>electrorheologic materials.
> 
>  The ones I've heard of tend to be used in magnetic clutches and the
>like.  They consist of thick oils loaded with powdered steel-under the
>influence of a magnetic field the material 'solidifies' (the powder
>consolidates).  The stuff would likely behave the same if you ran a
>current thru it (because of the resulting magnetic field).  No problem
>that it's an insulator-one variety of this stuff uses mercury as a
>matrix.

I seem to remember seeing a paper a short while back that used this 
fluid in pads attached to the gripping surface of a robotic arm. The
hand grips the part and then volage is applied thereby securing a custom
gripper for the part. Kinda cool idea, huh!

chris