Robotics

What is a Robot? — Sense → Think → Act

A robot is a machine that can sense its environment, think about what to do, and act on it. All robots follow this loop: SENSE (read sensors) → THINK (run code) → ACT (move motors). Even a self-driving car follows this loop thousands of times per second!

Sensors — How Robots Feel the World

Robots use sensors to gather data about their environment. Common sensors: ultrasonic (distance), infrared (line detection), accelerometer (tilt/movement), temperature, light, colour, and touch. Each sensor returns a value your code can use to make decisions.

Motors — Making Robots Move

Most robots move using DC motors (wheels) or servo motors (arms/joints). You control speed (0-100%) and direction (forward/backward for DC, angle 0-180° for servos). A two-wheeled robot steers by running the motors at different speeds!

Feedback Loops — Staying on Track

A feedback loop uses sensor readings to constantly correct the robot's behaviour. The robot checks what's happening, compares it to the goal, and adjusts. This is how robots stay on a line, hold a steady speed, or keep their balance!

State Machines — Robot Behaviour Logic

Complex robot behaviour is modelled as a state machine. The robot can be in one state at a time (EXPLORING, AVOIDING, CHARGING). Sensor events trigger transitions between states. State machines make robot logic clear, predictable, and easy to debug.

Pathfinding — Finding the Way

How does a robot find a path from A to B while avoiding walls? One answer: Breadth-First Search (BFS). BFS explores all nearby cells first, then farther cells, guaranteeing the shortest path. This is the same algorithm used in GPS navigation and game AI!

Mini Project — Simulated Delivery Robot

Let's build a complete simulated delivery robot! It navigates a grid map, picks up packages, avoids obstacles, and delivers them. It uses everything: state machine, pathfinding, sensors, and motor control — all in pure Python simulation.