"I want to build a billion tiny factories, models of each other, which are manufacturing simultaneously. … The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom. It is not an attempt to violate any laws; it is something, in principle, that can be done; but in practice, it has not been done because we are too big." -Richard Feynman (1918-1988)
Engineering works with science to bring about new technologies. Sometimes it is hard to see the small changes and advances as they happen, but changes are always in the works. To really get a feel for the pace of change over the past few decades, think back fifty years or so. In 1960, the space program was just underway, but the biggest computers were slower than today’s pocket calculator. There was a phone booth on every corner because cell phones did not exist. And jet airplanes for commercial travel? There were a few, but most planes used propellers.
Technological changes have transformed our world. As science advances, so does technology. Think about the changes that have occurred since 1960. The amazing thing is that the rate of change is constantly accelerating.
New discoveries and advances provide a framework for future technological growth in many directions. The following sections highlight a few of the fields of technology that will likely be in the news for some time.
Nanotechnology
Physicist Richard Feynman’s address to the annual meeting of the American Physical Society at the California Institute of Technology in 1959 marked the beginning of what became the science of nanotechnology. His talk, entitled "There’s Plenty of Room at the Bottom," can be viewed on the internet at www.zyvex.com/nanotech/feynman.html.
According to the Center for Responsible Nanotechnology (www.crnano.org), nanotechnology is the engineering of functional systems at the molecular scale.
He called for better electron microscopes and explained that almost any problem could be solved if we could merely look at structure on a molecular level. At the time, computers were so large they filled entire rooms. Feynman spoke of miniaturizing them and the benefits that would result. He mentioned putting "mechanical surgeons" inside blood vessels to repair the body from the inside. Perhaps most exciting, he envisioned building tiny machines, atom by atom. Feynmann offered cash prizes for people who could achieve feats like making the page of a book so small it could only be read by an electron microscope. With this speech, Feynman got the whole field started, and a mad rush to "the bottom" has existed ever since.
How small is the playing field of nanotechnology? Imagine taking a human hair and reducing it down 50,000 to 100,000 times. You’d be in nanometer territory, one billionth of a meter, roughly the length of three to six atoms placed side by side.
Originally, nanotechnology referred to building working machines including motors, robots, and even computers that would be only a few nanometers wide. However, the meaning has changed a bit over time. Today, nanotechnology refers to manufacturing materials by controlling matter at the atomic or molecular scale—anything smaller than 100 nanometers wide, with novel properties.
"In living cells, there are tiny machines that put molecules together to make things like potatoes and trees. People are learning to do this, and when we get good at it, we’ll have machines that can make things like solar cells, computers, and spaceships. Like the machines that make the wood in trees, these machines will be able to make things with low cost and almost no pollution."
At the nanoscale, materials show different properties and behave differently from larger-scale materials. The website of the National Nanotechnology Initiative (www. nano.gov/html/facts/whatIsNano.html) points out that many natural processes and materials operate at the nanoscale. The strength of a spider web, water repellancy of leaves, and ability of a fly to walk on the ceiling are all nanoscale phenomena.
A key benefit of nanotechnology is that it is an improved manufacturing process. Control at the atomic level means that the process can be more efficient and, ultimately, less expensive. Because the field is so new, no one really knows where it is going. Predictions of its impact range from being able to make new and better tools, such as knives that never become dull, to making tiny, self-replicating robots the size of a grain of pollen—or smaller—that can run around and perform tasks independent from human guidance.
One of the possible applications of nanotechnology is in the manufacture of more efficient computers. Miniaturization has been one of the hallmarks of computer design and nanotechnology will allow miniaturization to unheard-of scales. Computers of the future may compare to today’s fastest machines the same way that our computers compare to the giant, plodding, tube-driven computers of the 1950s.
Molecular Medicine
Molecular medicine is another field that uses the small scale in practical applications. It studies and treats diseases on the molecular and cellular level by focusing on the biochemical processes at work. One example of the use of molecular medicine is in the study of catecholamines, which regulate immune and inflammatory responses in the body and regulate the "fight or flight" response. Catecholamines are neuro-transmitter chemicals in the brain; they include dopamine, epinephrine (adrenaline), and norepinephrine. Biochemist Julius Axelrod shared a Nobel Prize in Physiology or Medicine in 1970 with Bernard Katz and Ulf von Euler for work on the release and reuptake of catecholamines. The most interesting part of their work was the revelation that adrenaline is recycled (the "reuptake").
Epinephrine used as a drug treats cardiac arrest and is also used as a bronchodilator for asthmatics. It has a suppressive effect on the immune system. This is why allergy patients receiving immunotherapy are often given an epinephrine rinse prior to the allergen extract.
Axelrod’s story is a good example of how molecular medicine is in use today. In 1949, his work at the National Heart Institute on the effects of caffeine led him to an interest in the sympathetic nervous system and the study of epineph-rine and norepinephrine. His studies of the function of the nervous system at the molecular level led to development of drugs such as Prozac, which blocks the reuptake of the neuro-transmitter serotonin.
An application of nanotechnology in molecular medicine is a system used to perform DNA testing at the benchtop level. Using gold nanoparticles (typically 13-20 nanometers in diameter), the process simplifies molecular diagnostic testing and provides results to hospital laboratories that were formerly available only from large off-site labs. These instruments have diagnostic applications in blood screening, cardiovascular disease, neurodegenerative disorders, and oncology.
Robotics
What comes to mind when you hear the word "robot"? Anyone who has seen the Star Wars movies will most likely think immediately of C3PO or R2D2. While these robots make great movie characters, real robots are something completely different. Robots operating in manufacturing facilities generally look just like any other machine. Where they differ is in their controls. While other machines are controlled by a human operator, a robot has some degree of control over its motion. The robot has a computer with software that encodes the instructions for performing particular operations under specific conditions. In other words, a robot is a mechanical device controlled by a computer program that allows it to operate without direct human manipulation.
All robots have three basic parts: a computer, mechanical systems, and electronic systems. The computer is programmed to control the other parts of the robot and make decisions based on input. The mechanical systems are the devices that the robot uses to move and to manipulate objects. The electronic systems act as sensors and carry instructions from the computer to the mechanical and electronic components.
Currently, many robots are used to perform tasks that are repetitive and, therefore, fairly easy to program. They are very common on assembly lines, where a simple task is done repeatedly. The robot is able to determine when a part is in the correct position, and in some cases reposition it if necessary, and then perform the operation. Robots are also used to perform tasks that are too dangerous, or even impossible, for humans to perform. For example, robots have been used to disarm bombs, explore the Chernobyl nuclear reactor, and explore the ocean floor.
Fast Facts
One of the most amazing uses for a robot is the exploration of Mars. In 2003, NASA sent two robots, the Mars Exploration Rovers, to seek evidence about the history of water on Mars. These robots move across the surface using solar power and send photographs back to Earth. They also carry and use a number of instruments to analyze rocks and soil. The Rovers were initially designed to work for two months before wearing out, although the research team planned to use them as long as possible. At the time of this writing, in 2008, both Rovers continue to explore the surface of Mars and send information home to Earth.
The key difference between a robot and any other machine is the ability to make choices. For example, a remotely controlled toy car, which is operated by radio signals from a controller held by a person, is not a robot. A car that senses obstacles and changes direction to avoid them, on the other hand, could be considered a robot.
Despite how they are presented in movies, very few robots look at all like humans. A major reason for this is that walking on two legs is not a particularly efficient way to move from one place to another. Many robots—for example, welding robots on an automobile assembly line—do not need to move at all. For robots that do need to move from one place to another, wheels or tracks generally provide a stable and efficient platform. In situations where the ability to lift a leg over an obstacle is important, robot designers often use more than two legs. For example, Dante II, a robot built to explore inside volcanoes, has eight legs, closer to the design of a spider than that of a human.
One of the current challenges for robot designers actually has more to do with people than with the robots themselves. As robots are built for more and more tasks, they are more likely to be used by people with no training in dealing with them. Many designers believe that effective interaction will require communication methods that seem natural to humans. Toward this end, there is significant research underway involving speech recognition software that would allow verbal commands and responses. Nonverbal communication is important in human interactions, so roboticists are also working to develop gestures and even facial expressions for robots that would communicate with the general public. Research is even underway to give robots a personality.
New Energy Sources
As human civilizations become more complex, their demand for energy increases rapidly. The earliest agricultural cultures relied on human muscles to provide all the energy needed for food production and locomotion. As more complex societies found an increased need for energy, they harnessed the power of draft animals, the wind, and flowing water. In developed nations today, most energy comes from combustion of fossil fuels—coal, oil, and natural gas—along with smaller contributions from nuclear power and hydroelectric power.
Unfortunately, there are some limitations that accompany these energy sources. The combustion of fossil fuels is accompanied by pollution and is the greatest contributor of greenhouse gases in the atmosphere. Nuclear power generates radioactive waste that will remain dangerous for thousands of years. In addition, fossil fuels and nuclear fuels exist in limited amounts. Although we have not yet reached the end of their availability, we will someday. Hydroelectric power does not pollute but it does alter the flow of rivers as large dams are built. This introduces its own environmental problems. In addition, in many countries, very few suitable places remain in which water power can be tapped.
From the beginning of human history, some of the most important technological developments have involved new ways to produce or harness energy. This is certain to continue into the future. The demand for energy grows with population and advancements in other technologies and the limitations of our current sources means that new energy technologies will be needed. This will be a major focus of future research and development.
There is at least one country that uses almost no fossil fuels to produce electricity. Iceland produces about three-fourths of its electricity at hydroelectric power plants and about one-fourth from geothermal power plants. In addition, most of the heat for buildings is obtained from hot water from beneath the ground. Iceland is particularly suited for using geological sources of energy because it is located above several volcanoes.
Several alternative sources of energy already exist. They are very important in some regions of the world. For example, almost half of the electric power used in Denmark comes from wind power and about 40 percent of Brazil’s transportation fuel is ethanol. Overall, however, the world still relies predominantly on fossil fuels for its needs. One of the key considerations for alternative fuels is renewability. Unlike coal or oil, alternative fuels use resources that can be replaced.
Biofuels are produced from plant sources so they can be replaced by growing new crops. Ethanol, the most common biofuel today, can be produced from corn, sugar cane, or other plant materials. The main disadvantage of these fuel sources is that the crop production requires agricultural land that could be used for food production. In addition, the energy used in producing these fuels reduces their overall benefit. Research is underway to find ways to produce fuels from garbage, waste agricultural materials, and wood in order to tap resources that do not compete with food production.
Another research focus is on harnessing the natural motion of air and water to provide energy. In one way, this is not a new technology. Windmills and watermills were major power sources hundreds of years ago. Modern techniques are much more efficient, though. Wind turbines, with blades as long as 100 meters (330 feet), are used to produce electricity, which can then be transported through existing power lines.
Hydroelectric power plants already use the energy of falling water to produce electric power. Small-scale projects already exist that use the power of ocean waves and tides to generate electricity. The idea of wave generators for energy production has been around since the 1930s. Since ocean waves cause an elliptical motion, this can be harnessed to power mechanical motion, generating electricity, which is then piped ashore via undersea cable. There are many plans worldwide to use various designs for power, with the first U. S. plant being built by Pacific Gas and Electric Company off the coast of northern California. It’s not a big operation, consisting of only eight buoys, 21/2 miles offshore, but when the plant begins operating in 2012, estimates are that it can generate power for as many as 1,500 homes. Similar plans are in place for plants off the coasts of England, Portugal, and Scotland. Although the infrastructure can be expensive, once built, wind and water systems produce electric power using motion that has no cost.
Geothermal power is energy that is generated by using the heat stored beneath the surface of Earth. Currently geothermal plants provide less than 1 percent of the energy needs for the world.
Geothermal energy comes from beneath the earth. The planet’s interior is heated as radioactive materials break down (the same energy source we use in nuclear power plants). This heat slowly works its way toward the surface. Geothermal power plants use this heat to produce steam to run power plant turbines. Geothermal energy can also be used to heat buildings by pumping warm water into a heat pump and transferring its energy into the surrounding air.
One of the oldest sources of energy is once again becoming a prominent source of power—our sun. Solar energy is provided daily, free of charge, if we can find a way to make it work for us. Photovoltaic cells are familiar on calculators and landscape lighting. Large cells have been used to provide electrical power for homes and office buildings. So far, applications for generating electrical power for large-scale distribution have not been economical. In the future, improvements in the efficiency of the cell and reductions in production costs may provide a clean, reliable, and truly renewable source of electric power.
Solar cells are not the only means of harnessing the sun. Solar chimneys use sunlight to heat air so that it rises through a giant chimney. The moving air drives turbines that generate an electric current. An Australian company is currently planning a plant that will use a chimney to produce 200 megawatts of solar thermal power, providing electricity to around 200,000 Australian households.
The ultimate new technology for energy could come from the same reaction that powers the sun. In nuclear fusion, hydrogen atoms combine to form helium atoms, releasing large amounts of energy in the process. There are significant challenges to using nuclear fusion to provide power. The greatest is learning how to handle material at a temperature in excess of several million degrees. In 2006, a consortium of the European Union, India, Japan, China, Russia, South Korea, and the United States agreed to jointly build and operate a research project, known as ITER. The goal of the project, which will cost about $9 billion, is to "demonstrate the scientific and technological feasibility of fusion energy for peaceful purposes."
Fast Facts
According to the International Energy Agency (www.iea.org) in a statement released November 7 2007 if governments around the world stick with their existing energy use policies, the world’s energy needs will be well over 50 percent higher in 2030 than today. In the scenario presented, China and India together would account for 45 percent of the increase, as their energy use is set to more than double between 2005 and 2030.
Genetic Modification
Inside the cells of every living thing, genes carry instructions for cell activities. These genes, located in a section of the cell’s DNA, have the codes that tell the cell how to make proteins that perform many functions inside the cell. Genetic modification (also called genetic engineering) is the direct manipulation of the genes inside a living cell. The purpose of genetic modification is to change the way the cell functions.
Genetic engineering is done by isolating a gene in an existing organism that has the codes for a desirable trait. For example, some plants produce chemicals that are toxic to insects. The production of these pesticides is directed by one or more genes in the plant cell. The second step of genetic modification is insertion of the isolated gene into the DNA of a different organism. If the gene that directs production of an insecticide is implanted into the DNA of a plant that does not naturally produce it, the new plant—and its offspring—will have the ability to produce the compound.
Genetic engineering has been used to produce plants that resist certain pests. It has also been used in agriculture to develop crop plants, such as corn, that are immune to a particular herbicide. When the herbicide is used in a cornfield, it kills weeds but not the resistant crop. Genetic modification has been widely used to produce plants with specific characteristics, such as resistance to a particular disease, tolerance for frost, or extended freshness.
In the future, genetic engineering may be widely used in medicine. Proteins are hard to build in chemical manufacturing processes, but living cells produce proteins constantly. It may be possible to produce many protein-based drugs using genetically modified organisms. Bacteria and yeasts are easily managed in laboratory settings. Domestic animals, such as cattle, sheep, and goats, produce milk, which is a protein-rich substance. Genetic engineering may lead to production of useful compounds that can be isolated from the milk of these animals.
Fast Facts
People with diabetes do not correctly produce the protein insulin, which helps control sugar levels in the bloodstream. Until the 1980s, they had to use injections of insulin from cows or pigs. The first genetically engineered medicine was synthetic human insulin, approved by the United States Food and Drug Administration in 1982. Scientists used bacteria in which they inserted the directions for insulin manufacture. They were then able to use the bacteria to produce and harvest artificial insulin. Millions of people with diabetes now take human insulin produced by bacteria or yeast that is genetically identical to the insulin produced by human cells.
Researchers are currently looking for ways to modify genes within human cells. This may provide a new way to attack hereditary diseases. Gene therapy is a promising approach that offers a great deal of hope. The goal is to replace a defective gene with a healthy copy of the gene in order to correct a defective function in the cell. In 2000, a team of French scientists succeeded in curing young children suffering from a rare severe immune deficiency by inserting a therapeutic gene in the cells of their bone marrow.
Genetic engineering is just one of the many new technologies that you are likely to read about now and in the future.
