Re: Anisotropic friction to the extreme?

Yes it is possible and is being done.  Look carefully at windshield wiper 
blades you will see the sides are lubricated usually with graphite and the 
cut ends are exposed rubber. When the blade reaches the end of its travel 
the end comes into contact with the glass causing the blade to flip for 
the return trip. This is a physical effect using materials with different 
friction characteristics.

A second common application is in cross-country skis.  CC skis need the 
property of gliding in the forward direction and gripping in the back 
direction. [You probably haven't encountered this in Brazil so i recommend 
a trip to Norway next Summer.]  There are 3 methods that i am familiar 
with to accomplish this: 1. Ski waxes that grip snow crystals under 
pressure and loosen when pressure is released  There are a myriad of waxes 
for temperatures and snow conditions so this is an art as well as a 
science. 2. bristles, usually mohair, set into the ski bottoms so that the 
hair faces rearward ... glide forward, grip backwards[sort of like petting 
a cat against the grain].  3. a herring bone pattern on the ski bottom 
pointing forward lower friction in the forward direction.  There are 
probably advanced versions hence the trip to Norway[you can probably do it 
on the Web but you miss out on the cold] There is also a technique called 
skating such as in roller blading and ice and roller skating where only a 
low friction glide wax is used and the ski edges are used for forward 
propulsion. The principle here is vector force resolution.

In your case i would consider a physical composite of a low friction and 
high friction material engineered so thst force in the forward direction 
exposes the low friction surface and force in the backwards direction 
exposes the high friction material. This is very similar to the wiper 
blade operation