Редактирование: Molecular Machinery (раздел)

===SRG-II Speed Reducer Gear===

The SRG-II is another parallel-shaft speed reducer gear created by Mark Sims. It was designed and modeled completely from scratch using NanoEngineer-1 (Alpha 6). The goal of the SRG-II was to create a robust nanoscale gear complete with a casing and extended connector shafts. As you can see, the SRG-II looks every bit like a speed reducer gear. Although the casing is a single component, its atoms have been grouped into sections and hidden in the animated sequence above so that you can better visualize the casing arrangement.

The animation loop show a 9.6 picosecond segment of the first successful simulation of the SRG-II. The following parameters were used:

* Frames: 940
* Steps per Frame: 50.0 femtoseconds
* Temperature: 300K

As can be seen from this speed plot of the rotary motor attached to the pinion gear, the acceleration time was about 23 picoseconds. The duration of the simulation was 47 picoseconds.

Successfully simulating the SRG-II required two attempts. The first simulation of the SRG-IIa uncovered a design flaw in the casing, which was corrected in the SRG-IIb. The problem involved the top and bottom crossbeams that connected the front and back faces of the casing, which compressed the casing too tightly around the gears. Below you can see the difference between the casings of the SRG-IIa (left) and SRG-IIb (right). Notice the two upper and lower crossbeams missing from the SRG-IIb.

I also removed material from the left and right casing walls, creating four crossbeams at the corners. This reduced the number of atoms while maintaining the shape and rigidity of the casing structure. The rightmost image shows the casing, which is made of silicon carbide (SiC), a rigid material well suited for designing enclosures like this. It is displayed in '''''tubes display style''''' so that the two gears can be more easily seen. The gears are displayed in the '''''[http://en.wikipedia.org/wiki/Space-filling_model CPK display style]'''''.