Using an Arduino to control motors is one of the most common and beginner-friendly projects. Arduino is often better suited for motor control than a Raspberry Pi for simple applications because it's designed for real-time I/O and can handle the electrical noise from motors more robustly.

Here’s a practical Arduino playbook for the most common motor types—pick yours, wire it safely, then drop in the sample code.

Power & safety (read first)

• Do not power motors from the Arduino 5V pin. Use a separate supply sized for the motor’s stall current; tie grounds together (motor supply GND ↔ Arduino GND).

• Arduino pins source only a few mA—they drive a driver, not the motor.

• Add a flyback diode across DC motors/solenoids (stripe to +V) unless your driver has them built-in.

• Keep high-current wires short; add bulk caps near drivers (e.g., 100–470 µF + 0.1 µF).

1) Brushed DC motor

A) One direction (simple, cheap): N-MOSFET + diode

Parts: Logic-level N-MOSFET (e.g., IRLZ44N/IRLZ34N/AOZ128x), 1N5819/1N4007 diode, 100 Ω gate resistor, 10 kΩ gate pulldown.

Wiring (low-side switch):

• Motor + → external supply +

• Motor − → MOSFET D

• MOSFET S → GND

• Arduino PWM pin (e.g., D9) → 100 Ω → MOSFET G; 10 kΩ G→GND

• Diode across motor (stripe to +)

Code (speed control with PWM):

(Default PWM is ~490 Hz on most pins; ~980 Hz on 5/6. Audible whine is normal at low kHz.)

B) Both directions: H-bridge (TB6612FNG/DRV8833 preferred)

Wiring (one channel): PWMA → D5, AIN1 → D7, AIN2 → D6, STBY → D8 (HIGH), motor across A01/A02, VM to motor supply, VCC to 5 V, GND common.

Code:

2) Hobby servo (SG90, MG996R, etc.)

• Provide 5–6 V from a separate supply; connect GNDs together.

• Signal wire goes to any digital pin (Servo library handles timing).

Code (position control):

3) Stepper motor

A) Bipolar stepper + A4988/DRV8825/TMC (STEP/DIR)

Basics: Set current limit (Vref), choose microstep mode (MS1–MS3), add 100–220 µF near VMOT.

Wiring: STEP → D2, DIR → D3, EN → D4 (LOW=enable). Coils to A1/A2/B1/B2, VMOT to motor supply, GND common.

Code:

Tip: For smooth moves, use acceleration profiles (e.g., AccelStepper library).

B) 28BYJ-48 + ULN2003 (unipolar)

Use the built-in Stepper library or AccelStepper’s FULL4WIRE. Connect IN1..IN4 to four Arduino pins.

4) BLDC via ESC (RC motors/fans)

ESCs accept servo-style pulses (≈1000–2000 µs). Many need an arming sequence.

Code:

Common pitfalls (and fixes)

• Motor won’t spin / resets Arduino: separate motor supply, add bulk cap, confirm common ground.

• Driver overheating: check current limit (steppers), add heatsink/airflow, ensure proper VMOT voltage.

• Noisy sensors / random behavior: twist motor leads, keep power/logic grounds star-connected, route motor wires away from signal lines, add snubbers/ferrites if needed.

• Servo jitter: dedicated 5–6 V rail with enough current; avoid long, thin wires.

Quick parts cheat sheet

• DC one-way: IRLZ44N + 1N5819 + 100 Ω gate + 10 k pulldown

• DC two-way: TB6612FNG (efficient) or DRV8833

• Stepper: A4988/DRV8825/TMC2209 + AccelStepper

• Servo/ESC control: Servo.h (use external 5–6 V supply)