Nanorobotics is the technology of creating machines or robots at or close to the microscopic scale of a nanometres (10^-9 metres). More specifically, nanorobotics refers to the still largely hypothetical nanotechnology engineering discipline of designing and building nanorobots. Nanorobots (nanobots, nanoids or nanites) would be typically devices ranging in size from 0.1-10 micrometers and constructed of nanoscale or molecular components. As no artificial non-biological nanorobots have so far been created, they remain a hypothetical concept at this time.

Another definition sometimes used is a robot which allows precision interactions with nanoscale objects, or can manipulate with nanoscale resolution. Following this definition even a large apparatus such as an atomic force microscope can be considered a nanorobotic instrument when configured to perform nanomanipulation. Also, macroscale robots or microrobots which can move with nanoscale precision can also be considered nanorobots.

Nanomachines are largely in the research-and-development phase, but some primitive molecular machines have been tested. An example is a sensor having a switch approximately 1.5 nanometers across, capable of counting specific molecules in a chemical sample. The first useful applications of nanomachines, if such are ever built, might be in medical technology, where they might be used to identify cancer cells and destroy them. Another potential application is the detection of toxic chemicals, and the measurement of their concentrations, in the environment. Recently, Rice University has demonstrated a single-molecule car which is developed by a chemical process and includes buckyballs for wheels. It is actuated by controlling the environmental temperature and by positioning a scanning tunneling microscope tip. Basic nanomachines are also in use in other areas. Nanotechnology coatings are already being used to make clothing with stain-resistant fibers and are used on swim suits to repel water, reduce friction with the water, and allow swimmers to go faster. Nanotech powders are being used to create high-performance sun-screen lotions and nanoparticles are helping to deliver drugs to targeted tissues in the body.

Nanorobotics theory

Since nanorobots would be microscopic in size, it would probably be necessary for very large numbers of them to work together to perform macroscopic tasks. These nanorobot swarms, both those which are incapable of replication (as in utility fog) and those which are capable of unconstrained replication in the natural environment (as in grey goo and its less common variants), are found in many science fiction stories, such as the Borg nanoprobes in Star Trek, nanogenes in the Doctor Who episode "The Empty Child", nanites in "I, Robot", "Stargate SG1" and nanobots in Red Dwarf. The T-1000 in Terminator 2: Judgment Day may be another example of a nanorobot swarm. The word "nanobot" (also "nanite", "nanogene", or "nanoant") is often used to indicate this fictional context and is an informal or even pejorative term to refer to the engineering concept of nanorobots. The word nanorobot is the correct technical term in the nonfictional context of serious engineering studies.

Some proponents of nanorobotics, in reaction to the grey goo scare scenarios that they earlier helped to propagate, hold the view that nanorobots capable of replication outside of a restricted factory environment do not form a necessary part of a purported productive nanotechnology, and that the process of self-replication, if it were ever to be developed, could be made inherently safe. They further assert that free-foraging replicators are in fact absent from their current plans for developing and using molecular manufacturing.

In such plans, future medical nanotechnology has been posited to employ nanorobots injected into the patient to perform treatment on a cellular level. Such nanorobots intended for use in medicine are posited to be non-replicating, as replication would needlessly increase device complexity, reduce reliability, and interfere with the medical mission. Instead, medical nanorobots are posited to be manufactured in hypothetical, carefully controlled nanofactories in which nanoscale machines would be solidly integrated into a supposed desktop-scale machine that would build macroscopic products.

The most detailed discussions of nanorobotics, including specific design issues such as sensing, power communication, navigation, manipulation, locomotion, and onboard computation, have been presented in the medical context of nanomedicine by Robert Freitas. Although much of these discussions remain at the level of unbuildable generality and do not approach the level of detailed engineering, the Nanofactory Collaboration^[1], founded by Robert Freitas and Ralph Merkle in 2000, is a focused ongoing effort involving 23 researchers from 10 organizations and 4 countries that is developing a practical research agenda^[2] specifically aimed at developing positionally-controlled diamond mechanosynthesis and a diamondoid nanofactory that would be capable of building diamondoid medical nanorobots.

Nubot

Nubot is an abbreviation for "Nucleic Acid Robots." Nubots are synthetic robotics devices at the nanoscale. Representative nubots include the several DNA walkers reported by Ned Seeman's group at NYU, Niles Pierce's group at Caltech, John Reif's group at Duke University, Chengde Mao's group at Purdue, and Andrew Turberfield's group at the University of Oxford.

Potential Applications

• Early diagnosis and targeted drug delivery for cancer^[3][4][5].
• Biomedical instrumentation^[6].
• Surgery^[7][8].
• Pharmacokinetics^[9].
• Diabetes^[10][11][12].

References

Bibliography

• K. Eric Drexler, Engines of Creation

• Robotic Spacecrafts
• Space Probes
• NASA Robot Links

Robotics in Medicine