Sensors, robots or micro:bit intro

A robot is a computer with a body. It senses the world, runs a program, and acts on what it learns. The same loop — input, process, output — runs inside every smart device, from a self-driving car to a pocket-sized board called the micro:bit.

What is a Sensor?

A sensor is a tiny part that turns something in the real world (light, heat, motion, sound) into a number a computer can read. Without sensors, a robot is blind and deaf. With sensors, the robot can react to what is happening around it.

Common Sensors and What They Detect

• Light sensor — measures brightness (is the room dark or sunny?)
• Temperature sensor — measures heat (is it hot or cold?)
• Accelerometer — detects tilt and shake (is the board moving?)
• Button — detects a press (did the user push it?)
• Microphone — picks up sound (is anyone clapping or talking?)
• Touch sensor — detects contact (did a finger touch the pin?)
• Compass — reads direction (which way is north?)

Input, Process, Output

1. Input — the sensor reads a signal from the world.
2. Process — the program decides what the signal means.
3. Output — the robot does something: a light flashes, a motor spins, a speaker beeps.

Meet the micro:bit

The micro:bit is a small, pocket-sized board built for learning. It has a 5x5 grid of red LEDs (output), two buttons labeled A and B (input), a USB port for power and code, and built-in sensors for light, temperature, motion, and direction. Edge pins around the bottom let you wire up extra sensors and motors.

Inputs vs. Outputs

• Inputs come IN to the board (button press, light reading, tilt).
• Outputs go OUT to the world (LED glow, speaker beep, motor spin).
• Some parts are sensors (read the world); others are actuators (act on the world).
• A program connects the two: when sensor X reads Y, do output Z.