Saturday, March 3, 2007
another from the tutorials - the nasa gear
Here I used another tutorial to recreate the Nasa gear. Two carbon nanotube were inserted into the workspace with a chirality of n = 16, m = 0 (actually only one is inserted, the other is copied from it). The chirality describes the asymmetry of the carbon latice. For a more in depth explanation of carbon nanotubes check out Physical Properties of Carbon Nanotubes by R. Saito et. al. These are formed into gear mechanisms by "transmuting" two carbon atoms at regular intervals around the tube from sp2 to sp3. Four additional C-sp2 atoms are added to each transmuted couplet to create a hexagonal tooth. The remaining unbonded carbons were then hydrogenated. The tubes were then placed into an interlocking position. Again building the gears really didn't take too long, but running the simulation gave my outmoded laptop a work out. I think I am going to have to break out my other rig, much more crunching power there.