[bionet.general] Artificial limbs?

mathers@titan.trl.oz (Steven Mathers) (03/06/90)

 I remember seeing a segment on 'Beyond 2000' about a new plastic-ish
substance being developed.  This was about a year or so ago, now.  the
interesting property of this stuff is that in a natural state it is a
viscous white liquid, but whith the application of an electrical
current, it goes hard pretty quickly.  Almost instantaneously.  How hard
it gets depends on the voltage applied (if I remember correctly).  the
sugested use of this stuff is a substitute for eleaborate mechanical
gear and braking systems. phew.
Ok, my questions are:
What does anyone know about this stuff?  'Beyond 2000' is a fairly
glitzy show, so I didnt get any real particulars.
What is the progress on it's development?

It occured to me that it may have a use for developing elegant
artificial limbs/ robotics, given the following assumptions:
1) The electrical charge applied to render the substance hard is not
prohibitive.
2) That (Im reaching back to high school physics here) like most
substances -- except water -- this stuff will take up less volume when
it hardens.

My idea is to put the stuff in long thin tubes, in a sort of hydralic
cylinder type arrangement, and let the vaccume force caused by the
reduction in volume when the substance goes from liquid to solid, do the
work.  So this would be a sort of artificial muscle arrangement.  Whack
a bunch of these in an artificial limb, mimicking the important muscles
in an arm, say, and put these under the electrical control of nerve
impulses via some amplifiers.
What do you think?

wlanders@thunder.lakeheadu.ca ("Wendy L. Anderson") (03/07/90)

mathers@TITAN

  Your idea would only work if the plastic returns to the liquid state
 afer the electric current has been removed.  If I recall correctly such
 is not the case with the plastic outlined on "Beyond 2000".

Wendy
 wlanders@thunder.lakeheadu.ca