Sense, think, act

Not every machine is a robot. A torch turns on when you flip a switch, but it does not sense or decide. A robot does all three of these:

• Sense: it gathers information about the world using sensors.
• Think: it decides what to do, using a controller running code.
• Act: it changes the world using actuators, like motors.

Example: a line-following car senses the dark line with a light sensor, decides which way to turn, and acts by driving its motors. Take away any one of the three and it stops being a robot.

Practice

Pick a robot you have seen, real or in a video. Write down what it senses, how it decides, and how it acts. If you cannot fill all three, is it really a robot?