Have you ever wondered what it would be like to drive a steam-powered locomotive through your blood vessels? It is a weird thought, I must admit; I wonder, though, if it was the inspiration for the University of Stuttgart researchers Clemens Bechinger and Valentin Blickle, who invented the world’s smallest steam engine at a whopping 3 micrometers (1 micrometer is a 1000 times less than a millimeter).

The general thought is that the physics of the microscopic world differ from the physics of the macroscopic world. If you walk over a well mowed lawn it would only take you a few moments to cross the span of several feet; however, if you were a bug, those same few feet, would become a dense, nearly impassible jungle. Furthermore, we in the macroscopic world can easily pass through air or water, but at the microscopic level, gases and liquids are far more viscous. Bacteria, viruses and other cellular tissue have evolved efficient methods to maneuver through this viscosity, but this physical difference is a major limitation for the development of nanotechnology.

Although Bechinger and Blickle have not yet found a practical use for their invention, it does show that the technology and engineering we use in the real-world can actually be scaled down and successfully used in the microscopic world; this is a key step in the development of nanotechnology.

Korean scientists have also developed a 1 millimeter sized micro-robot which they hope can one day be utilized for extremely complex micro-surgeries and drug delivery directly to diseased tissue. In a lab, the researchers successfully maneuvered the small robot through an artificial blood vessel, with the use of a novel external magnetic field navigation system. This system allows the robots to travel in a method that is similar to how bacteria move: corkscrew-like motions for forward/backward movement and side-to-side or “translational” movement for changes in the left or right directions. Obviously, this technology is still in its infancy. One millimeter robots are probably still too large for many effective treatments in a living organism; however, it is definitely another important initial step in the development of nanotechnology.

The problem: do we really want nanotechnology? Obviously little tiny robots can revolutionize healthcare, lead to incredible innovations in vascular surgery, tumor resection and directed chemotherapy, but there many potential drawbacks and limitations that must be overcome. Inventing useful and functional robots that can perform these tasks is only part of the problem. Per surgery we could be dealing with hundreds of tiny robots in our bodies. How do we get the robots out of our bodies after surgery? Will they dissolve? Can they be programmed to remove themselves safely from the body? Or will they simply lie dormant in the body for the rest of our lives?

Furthermore, technology has made our lives easier, but with more technology, the likelihood of something going wrong becomes greater and greater. I recently leased a new car, which, in the first six months, had to be taken to the dealer due to random computer issues. What would the likely fail rate of nanotechnology be? Dealing with a car is one thing, but dealing with your health is something different.

I would hate to go into the hospital for surgery to remove a tumor, and then wind up with an amputated leg or worse, solely because I was injected with nano-robots infected with some computer virus. That would not be fun. Of course, fear is no reason not to push the envelope; however, I hope that before we begin using this type of technology, we contemplate and attempt to deal with all the possible consequences.