Nanorobotics

Nanorobotics is the emerging technology field creating machines or robots whose components are at or close to the scale of a nanometer (10−9 meters). More specifically, nanorobotics refers to the nanotechnology engineering discipline of designing and building nanorobots, with devices ranging in size from 0.1-10 micrometers and constructed of nanoscale or molecular components.The names nanobots, nanoids, nanites, nanomachines or nanomites have also been used to describe these devices currently under research and development.

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 might be in medical technology. which could be used to identify and destroy cancer cells. Another potential application is the detection of toxic chemicals, and the measurement of their concentrations, in the environment. Rice University has demonstrated a single-molecule car developed by a chemical process and including buckyballs for wheels. It is actuated by controlling the environmental temperature and by positioning a scanning tunneling microscope tip.

Another definition is a robot that allows precision interactions with nanoscale objects, or can manipulate with nanoscale resolution. Such devices are more related to Microscopy or Scanning probe microscopy, instead of the description of nanorobots as molecular machine. Following the microscopy definition even a large apparatus such as an atomic force microscope can be considered a nanorobotic instrument when configured to perform nanomanipulation. For this perspective, macroscale robots or microrobots that can move with nanoscale precision can also be considered nanorobots.

Nanorobotics theory

According to Richard Feynman, it was his former graduate student and collaborator Albert Hibbs who originally suggested to him (circa 1959) the idea of a medical use for Feynman's theoretical micromachines (see nanotechnology). Hibbs suggested that certain repair machines might one day be reduced in size to the point that it would, in theory, be possible to (as Feynman put it) "swallow the doctor". The idea was incorporated into Feynman's 1959 essay There's Plenty of Room at the Bottom.

Since nanorobots would be microscopic in size, it would probably be necessary for very large numbers of them to work together to perform microscopic and macroscopic tasks. These nanorobot swarms, both those incapable of replication (as in utility fog) and those 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 and The Outer Limits episode The New Breed.


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 their current plans for developing and using molecular manufacturing do not in fact include free-foraging replicators.

The most detailed theoretical discussion of nanorobotics, including specific design issues such as sensing, power communication, navigation, manipulation, locomotion, and onboard computation, has been presented in the medical context of nanomedicine by Robert Freitas. Some of these discussions remain at the level of unbuildable generality and do not approach the level of detailed engineering.



Potential applications for nanorobotics in medicine include early diagnosis and targeted drug-delivery for cancer, biomedical instrumentation surgery,pharmacokinetics monitoring of diabetes, and health care.

In such plans, future medical nanotechnology is expected to employ nanorobots injected into the patient to perform work at a cellular level. Such nanorobots intended for use in medicine should be non-replicating, as replication would needlessly increase device complexity, reduce reliability, and interfere with the medical mission.

Nanotechnology provides a wide range of new technologies for developing customized solutions that optimize the delivery of pharmaceutical products. Today, harmful side effects of treatments such as chemotherapy are commonly a result of drug delivery methods that don't pinpoint their intended target cells accurately. Researchers at Harvard and MIT, however, have been able to attach special RNA strands, measuring nearly 10 nm in diameter, to nano-particles, filling them with a chemotherapy drug. These RNA strands are attracted to cancer cells. When the nanoparticle encounters a cancer cell, it adheres to it, and releases the drug into the cancer cell.This directed method of drug delivery has great potential for treating cancer patients while avoiding negative effects (commonly associated with improper drug delivery).


Another useful application of nanorobots is assisting in the repair of tissue cells alongside white blood cells. The recruitment of inflammatory cells or white blood cells (which include neutrophils, lymphocytes, monocytes and mast cells) to the affected area is the first response of tissues to injury.  Because of their small size nanorobots could attach themselves to the surface of recruited white cells, to squeeze their way out through the walls of blood vessels and arrive at the injury site, where they can assist in the tissue repair process. Certain substances could possibly be utilized to accelerate the recovery. The science behind this mechanism is quite complex. Passage of cells across the blood endothelium, a process known as transmigration, is a mechanism involving engagement of cell surface receptors to adhesion molecules, active force exertion and dilation of the vessel walls and physical deformation of the migrating cells. By attaching themselves to migrating inflammatory cells, the robots can in effect “hitch a ride” across the blood vessels, bypassing the need for a complex transmigration mechanism of their own.

Nanorobots

Teams around the world are working on creating the first practical medical nanorobot. Robots ranging from a millimeter in diameter to a relatively hefty two centimeters long already exist, though they are all still in the testing phase of development and haven't been used on people. We're probably several years away from seeing nanorobots enter the medical market. Today's microrobots are just prototypes that lack the ability to perform medical tasks.In the future, nanorobots could revolutionize medicine. Doctors could treat everything from heart disease to cancer using tiny robots the size of bacteria, a scale much smaller than today's robots. Robots might work alone or in teams to eradicate disease and treat other conditions. Some believe that semiautonomous nanorobots are right around the corner -- doctors would implant robots able to patrol a human's body, reacting to any problems that pop up. Unlike acute treatment, these robots would stay in the patient's body forever.

Another potential future application of nanorobot technology is to re-engineer our bodies to become resistant to disease, increase our strength or even improve our intelligence. Dr. Richard Thompson, a former professor of ethics, has written about the ethical implications of nanotechnology. He says the most important tool is communication, and that it's pivotal for communities, medical organizations and the government to talk about nanotechnology now, while the industry is still in its infancy.

Will we one day have thousands of microscopic robots rushing around in our veins, making corrections and healing our cuts, bruises and illnesses? With nanotechnology, it seems like anything is possible.

Medical Nanobots

Medicine is the on the most exciting applicaiton areas for anobots. It may become possible to inject a fleet of nanobots to perfom vital work inside a human body without resorting to surgery. Imagine toothpaste full of nanobots equipped to locate and destroy plaque or nanobots built to clean a diseased blood vessel.

Plaque Attack 
The diseased section of the blood vessel is covered with a type of plaque containing cholesterol.

Cryonics

This technology exists right now. You can arrange to have your body frozen to -321° Farenheit shortly after death in the hope that scientists in the future will be able to revive you and reverse whatever caused your death. Unfortunately, you can’t get frozen while you’re still alive and try to be revived, say, a week later; US law states that a person must be declared officially dead before they can legally be frozen. Otherwise you enter the tricky territory of assisted suicide (since the freezing process will kill you). Oh, also it runs around $150,000. But in the Utopian future, you won’t need money, right?

There are a number of exciting breakthroughs coming in the next few decades that may lead to much longer lifespans and even, possibly, immortality. Let’s just hope we’re all still alive when these discoveries happen!

Computer Brains

Why all this effort to save the body, when all you really need to save is the brain? That’s the seat of your consciousness, after all. If your body gives out, you could just implant your brain into a new one, cloned from your cells and kept in cold storage until it’s needed. The problem is that our delicate cerebral nerve tissue doesn’t do well after it’s been scarred by surgery. Paraplegics and quadraplegics only have some nerve damage; a brain transferred to a new body would mean all of its connections are severed and reattached.

A more achievable goal is to only transplant the sections of the brain that maintain memory, consciousness, and “identity.” A person would wake up in a new body with full control of their motor functions. At the University of Pittsburgh, over a dozen stroke victims have regained control of paralyzed limbs by receiving injections of brain cells — and not even from their own bodies. This means that the brain might be resilient enough to endure some kind of transplantation.

Nanotechnology

Aging is a cellular process, so the only way to stop it (or reverse it) may be on the cellular level. That’s where nanotechnology comes in. The term describes microscopic devices, materials, or even robots, that can revive cells, attack viruses, repair organs, even deliver precision drug or gene therapies. Nanorobots would also destroy cancer cells more effectively than any current treatment.

For example, in 2004, researchers at Rice University sent gold “nanoshells” after tumors in mice. The shells bonded to the cancers and, when heated by a laser, were destroyed — taking the cancer cells with them. If nanomachines can be shrunk to the size of molecules, they could theoretically medicate and repair a body indefinitely, which means immortality. Research into various forms of nanomedicine is taking place all over the world, at a cost of $4 billion a year.

Replacement Organs

From heart attacks to kidney failure, many of the causes of death come from one or more of our organs not working properly. One way to solve that problem is to clone replacement parts from your own cells ahead of time, so if you need a new lung, it’s ready to go. And since you’re implanting something made from your own DNA, there’s no risk of tissue rejection.

The technology for this already exists: heart valves, ears, and fingers have been successfully grown in a lab, and replacement bladders have been transplanted into patients in the United States. The doctors behind that triumph are awaiting full FDA approval for more operations. Human lifespans gained about 30 years when most infectious diseases were wiped out; ending tissue failure as a cause of death could add 30 more.