epmp09@castle.ed.ac.uk (J Hearns) (12/24/90)
Re the recent posting about force--feedback systems and fluids which change properties on bing subjected to electric fields. I beleive these are called electro-rheologic materials. Lotus uses them in its new generation of active suspension. I have seen film of a fluid which is held between two planar electrodes, then falls away when the current is switched off. There are also magnetic fluids which move inresponse to magnetic fields ( they have very fine magnetic particles in suspension, and are used to make specialised bearings I beleive). For more info, your best bet is probably Scientific American - I dimly remember an article on this stuff. Happy Christams all!