| The principal goal of molecular nanotechnology (MNT) is to develop a manufacturing technology able to inexpensively manufacture most arrangements of atoms that are consistent with physical law. In terms of its precision, flexibility, and low cost, this will be the ultimate manufacturing technology in human history. Two central mechanisms have been proposed to achieve these goals at the molecular scale: (1) programmable positional assembly and (2) parallel assembly.
Programmable positional assembly at the molecular scale is the central mechanism for achieving both great flexibility in manufacturing and the ultimate in molecular manufacturing precision. (Positional assembly is a manufacturing procedure in which components used in a construction are held in known positions and are constrained to follow desired intermediate physical pathways throughout the entire construction sequence; Chapter 4.) Methods for achieving positional assembly at the molecular scale are currently under active investigation by many research groups worldwide. Some of this work, especially mechanosynthesis work focused on positional assembly of diamond and diamond surfaces, will be the subject of a future publication.
Parallel assembly, whether using self-assembly, large manipulator arrays, or other self-replicating systems, is the central mechanism for achieving low cost manufacturing. (Parallel assembly is a manufacturing procedure in which a large number of product components or product objects are manipulated simultaneously in order to build bigger, more complex, or more numerous product objects; Section 5.7.) Self-replicating machines can make massively parallel manufacturing possible. System architectures by which this goal could be achieved, including specific conceptual architectures for nanofactories or molecular assemblers that should be capable of both molecular manufacturing and mechanical self-replication, are one important objective of the present work.
This book also offers the first general review of the voluminous theoretical and experimental literature pertaining to physical selfreplicating systems since the NASA report and survey on self-replicating systems (SRS) which was published in the 1980s (more than 20 years ago).2 The principal focus here is on self-replicating machine systems. Most importantly, we are primarily concerned with “kinematic”3,4 self-replicating machines: machine systems in which actual physical objects, not merely patterns of information, undertake their own replication in physical space. |
