There are robots all around us.Some do very difficult as like flying airplanes and driving subway trains.And some do simple jobs.
When an automatic(自动的)washing machine is switched on ,water goes in.The machine waits until the water is hot before washing the clothes.It does this by“feedback(反馈)”.Information about what’s happening is “feedback” into the robot to tell it what to do next.
Our eyes,ears and other senses (感官) are our feedback.They tell us what’s happening around us.So robots are like people in two ways.They work and they have feedback.
But very few robots look like people Many are hidden away.Robots control (控制) the temperature of our houses,our cookers and our hot water systems.We can set the controls to the temperature we want.The robot does the rest .Its feedback usually comes from a thermostat (自动调温器).
One kind of thermostat is a strip(条带)of metal(金属),which bends when it gets hot.At the right temperature,it bends just enough to work a switch.This turns off the heat.As the air around it gets cool ,the metal gets straight,and this turns the heat on again.