.provide feedback to the controller about the robot's environment, a limited sense of sight and sound

Tell students that animals, including humans, use their senses to collect data from the environment. This collected data is used to help make decisions; for example, if you touch a hot stove, you will pull your hand away, or if you see that the street is clear of cars, you know it is okay to cross the street. These senses are important because they provide important feedback about the environment.

Have the class participate in naming the different senses humans use; sight, hearing, touch, taste, and smell. Have students share ideas on how humans collect data from the environment using these five senses. Ask: What do these senses tell you about your environment? Elicit answers from students that reflect decision-making. For example, touch can tell you if something is too hot or too cold. Hearing can tell you the type of environment you’re in. Sight can tell you how far away obstacles might be.

Introduce students to the idea that robots also use senses, in the form of sensors, to collect information from the environment. Ask: Why do robots need sensors? Explain that robots need sensors to make decisions about tasks, like how to move or where to go next. Just like a student needs to wait until there is no traffic to cross the street, a robot needs to have an understanding about its surroundings. Ask: How do humans use their senses to make observations about their surroundings? Answers should include seeing what’s around them, hearing noises that give them clues to what’s nearby, and feeling items that might be near them.

Ask students to each draw a map of the classroom or room they are in. Give them a few minutes to make their maps. After students have finished making their maps, ask: What senses did you use to make your maps? Most students will have relied heavily on their sense of sight. Ask: If you could not see, what other senses could you use? Explain that some robots make maps of their environment using their various senses.

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