Passage 1There are robots all around us. Some do very complicated jobs like flying airplanes and driving subway trains. And some do one simple job. When an automatic washing machine is switched on, water pours in. The machine waits until the water is hot before washing the clothes. It does this by “feedback”. Information about what is happening is “fed back” into the robot to tell it what to do next. Our eyes, ears and other senses are our feedback. They tell us what is going on around us. So robots are like people in two ways. They work and they have feedback. In some ways robots are better than people. They work quickly, but do not make mistakes. They do not get bored doing the same job over and over again. And they never get tired. So robots are very useful in factories. They can be taught to do many different jobs. First their electronic brains must be shown how the job is done. A person moves the robot’s “arms” and “hands” through each part of the job. The robot’s brain remembers each move. When the robot is put to work on its own, its brain controls the rods, wheels and motors that move its arm. When the robot is needed for a new job, its electronic memory is “wiped clean”. Then it is taught how to do its new work. If the robot’s hand stops working, or if something gets in the way, it cannot do the next part of the job. So it stops and signals for help. Then a human engineer attends to the fault. The most “intelligent” robots can move and see. Their eyes are cameras. Their metal fingers can feel shapes and even find out how hot and cold objects are. These robots have computer brains, linked to their eyes and finger, which control their actions.5. How does a robot work?