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| In 1995 about 700,000 robots were
operating in the industrialized world. Over 500,000 were used in Japan, about
120,000 in Western Europe, and about 60,000 in the United States. Many robot
applications are for tasks that are either dangerous or unpleasant for human
beings. In medical laboratories, robots handle potentially dangerous materials,
such as blood or urine samples(尿样). In other cases, robots are used in
repetitive, unchangeable tasks in which human performance might degrade over
time. Robots can perform these repetitive, high-precision operations 24 hours a
day without fatigue. A major user of robots is the automobile industry. General
Motors Corporation uses approximately 16,000 robots for tasks such as spot
welding(点焊), painting, machine loading, parts transfer, and assembly. Assembly
is one of the fastest gnawing industrial applications of robotics. It requires
higher precision than welding or painting and depends on low-cost sensor systems
and powerful inexpensive computers. Robots are used in electronic assembly where
they load microchips on circuit boards. Activities in environments that cause great danger to humans, such as locating sunken ships, cleanup of nuclear waste, exploring for underwater mineral deposits, and active volcano exploration, are ideally suited to robots. Similarly, robots can explore distant planets. NASA’s Galileo, an unmanned space probe, traveled to Jupiter in 1996 and performed tasks such as determining the chemical content of the Jovian atmosphere. Robots are being used to assist surgeons in installing artificial hips, and very high-precision robots can help surgeons with delicate operations on the human eye. |