Study guide — what to focus on

This module is curated — the teaching is a top free course (linked in the card above); our job is to point you at the right things, make you prove it, and certify you.

The plan

1. Watch the course (the card above). It drives real motors from an Arduino through an H-bridge — don't memorise the code, aim to understand the ideas below.
2. Focus on these — they're what the check tests and what you'll use for real:
   • A motor is not an LED — it draws far more current than a pin can give and kicks back voltage spikes, so it always sits behind a driver, never on a bare pin.
   • Direction = the H-bridge — four switches that flip the voltage polarity across the motor, so it can run forward or backward.
   • Speed = PWM — the same fast on/off duty-cycle trick you met with LEDs, now setting the motor's average power (it keeps torque, unlike just lowering the voltage).
   • The driver's pins — on an L298N, PWM the EN pin for speed and set the IN pins for direction.
   • Back-EMF & the flyback diode — when a coil switches off it fights back; a diode gives that current a safe path (integrated drivers include it).
   • Motor types — brushed DC (simple, cheap), BLDC (no brushes, electronically commutated by an ESC — quieter, longer-lived), and stepper (moves in fixed steps for precise open-loop positioning; microstepping smooths it out). Same rule for all: they need a driver.
3. Prove it in Forge (next section) — describe a motorised device and read how it wires the driver in.
4. Take the K-Check to earn your certificate.

Why this connects to building real products

Anything that moves — a robot wheel, a pump, a fan, a camera gimbal, a locking mechanism — is a motor, and a motor is where a lot of first prototypes quietly fail: someone wires it straight to a pin and burns out the board. The whole point of this module is the reflex that a spinning load needs a driver between it and the brain. In Forge, when you describe a motorised device, that's exactly what you'll see — the design reaches for a motor-driver block, splits motor power from logic power, and gives the microcontroller the speed (PWM) and direction (H-bridge) control it needs. Knowing why lets you read why Forge builds it that way — and later, size the driver and write the firmware yourself.

Time to apply it. The course showed you that a motor never hangs off a pin — it sits behind a driver that handles the current, an H-bridge that sets direction, and PWM that sets speed.

Send the prompt below in Forge Design and watch it pull in a motor-driver block rather than wiring the motor straight to the microcontroller — then read how it routes speed (PWM) and direction (forward/reverse) control, and how it keeps motor power separate from logic power.

As you read Forge's answer, map it back to the course: which pins carry the PWM speed signal? Which set direction? That link — the driver you watched on the bench and the one Forge selects for you — is the whole point.