The transcript of an email interview Robert Freitas is up at lifeboat.com
What I found to be the highlights of the interview:
1. Culminating 5 years of intermittent effort Robert Freitas has finished his latest theoretical scaling study of a new diamondoid medical nanorobot called the "chromallocyte". This is the first full technical description of a cell repair nanorobot ever published.
One conceptually simple form of basic cell repair is chromosome replacement therapy (CRT), in which the entire chromatin content of the nucleus in a living cell is extracted and promptly replaced with a new set of prefabricated chromosomes which have been artificially manufactured as defect-free copies of the originals. The chromallocyte is a hypothetical mobile cell-repair nanorobot capable of limited vascular surface travel into the capillary bed of the targeted tissue or organ, followed by extravasation, histonatation, cytopenetration, and complete chromatin replacement in the nucleus of one target cell, and ending with a return to the bloodstream and subsequent extraction of the device from the body, completing the CRT mission....
2. In February, 2007, Robert Freitas and Ralph Merkle completed the core of a major three-year project to computationally analyze a comprehensive set of DMS reactions and tooltips that could be used to build diamond, graphene (e.g., carbon nanotubes), and all of the tools themselves including all necessary tool recharging reactions.
So far they have defined a total of 53 reaction sequences incorporating 252 reaction steps with 1,192 individual DFT-based reaction energies reported. (These reaction sequences range in length from 1-13 reaction steps (typically 4) with 0-10 possible pathological side reactions or rearrangements (typically 3) reported per reaction.) The reactions have been laid out in tables and systematized.
These reactions will form the core of our roadmap to develop diamond mechanosynthesis along a direct path that leads, ultimately, to the design and construction of the first diamondoid nanofactory.
3. Based on the computational chemistry work, their latest estimates suggest that an ideal research effort paced to make optimum use of available computational, experimental, and human resources would probably run at a $1-5M/yr level for the first 5 years of the program, ramp up to $20-50M/yr for the next 6 years, then finish off at a ~$100M/yr rate culminating in a simple working desktop nanofactory appliance in year 16 of a ~$900M effort.
4. Robert Freitas believes that early nanofactories necessarily will be extremely primitive. They will be very limited in the composition and complexity of products they can build and in the types of chemical elements and feedstocks they can handle. They will be fairly unreliable and will require significant supervision and maintenance. They will be relatively expensive to own and operate. Over a period of perhaps 10-20 years, nanofactory costs and capabilities will slowly improve and product costs will gradually drift downward toward the likely $1/kg regulatory floor, giving society some time to adjust to new threats as nanofactories become increasingly ubiquitous in our environment and economy.
5. The interview also discusses details about feedstock choices for nanofactories, ecophages and nanoshields.