Programmable positional assembly: The ability to place individual atoms precisely and in a reprogrammable way is the gateway to super low-cost and high performance manufacturing. This method of manufacturing is frequently referred to as “bottom-up”, because it would build products from the bottom up, as opposed to “top-down”, the traditional way of manufacturing products.
Molecular assembler: This is the machine that does the positional assembly. Think robot arm, but made out of somewhere between 3,000 and 4,000,000 atoms. Very few engineers or scientists have looked into molecular assembler designs. The most famous are Eric Drexler, Ralph Merkle, and Robert Freitas.
Parallel assembly: Because assemblers would be extremely small, you’d need billions and billions of them to build human-sized products in a reasonable timeframe. In parallel assembly, numerous assemblers would cooperate with one another to build useful products. They would all need to be programmed to work together in an organized way.
Diamondoid mechanosynthesis: Abbreviated as DMS, diamondoid mechanosynthesis refers to the chemical synthesis of diamondoid nanostructures based on positional assembly. One of the challenges of DMS would be removing the numerous hydrogen atoms that cover the surface of diamond structures, depositing carbon atoms in a designated pattern, then restoring that layer of hydrogen. Research is underway on the technology of DMS. You can read more on DMS at this web page.
Nanofactory: Sometimes fancifully referred to as a matter compiler, a nanofactory would be a manufacturing unit, possibly around the size of a microwave, that takes in simple hydrocarbons and electricity, converts them into feedstock, and uses many trillions of molecular assemblers to manufacture human-scale products. Most of the moving parts in nanofactories would be built out of diamond. Because nanofactories could have tremendous technological capabilities, it is important that they be regulated carefully. The regulation of nanocomputers is a particularly significant concern, due to the threat from AI, among other reasons.
Superproducts: Because nanofactories would build diamondoid products from the atoms up, they could arrange them for superior performance. Tiny structural flaws would be non-existent, making missiles and body armor extremely strong. If superproducts go entirely unregulated, anyone with a nanofactory will be able to build computers billions of times faster than today’s, engines thousands of times more powerful, and materials 10-100 times stronger.