How to control motors with arduino simulink?

Here’s a practical, Simulink-first recipe you can follow today. It covers DC motors (via H-bridge), servos, and steppers — using only the Simulink Support Package for Arduino Hardware blocks.

0) One-time setup (5 minutes)

1. In MATLAB: Home ▸ Add-Ons ▸ Get Add-Ons ▸ install Simulink Support Package for Arduino Hardware.
2. Plug your Arduino (Uno/Nano/MEGA/Leonardo/etc.).
3. In Simulink: Modeling ▸ Model Settings ▸ Hardware Implementation, set Hardware board = Arduino ….
4. In Solver, choose Fixed-step, discrete (e.g., fixed-step size = 0.01 s).
5. For live tuning, enable Run on hardware ▸ External mode (Monitor & Tune).

Power rule: Never power the motor from the Arduino 5 V pin. Use a separate motor supply, share GND with the Arduino, and use a driver (L298N, TB6612FNG, DRV8833, A4988, etc.).

1) DC motor with H-bridge (L298N / TB6612FNG)

Wiring (example pins)

• ENA/PWMA → Arduino D5 (PWM)
• IN1 → D7, IN2 → D8
• Motor + supply (e.g., 7–12 V) to driver VIN; common GND with Arduino.

Simulink blocks

• PWM (Analog Write) block → pin 5 (duty 0–255 or 0–1 depending on version).
• Digital Output blocks (2×) → pins 7 and 8 for direction.
• Slider Gain (0–1) or Constant → duty input.
• Optional: Analog Input A0 for a potentiometer speed knob; Scope for logging.

Direction logic

• CW: IN1=1, IN2=0
• CCW: IN1=0, IN2=1
• Brake: IN1=1, IN2=1 (driver-dependent)
• Coast: IN1=0, IN2=0

Tip: If you hear audible whine, try a different PWM pin/timer or a driver that supports higher-freq PWM. Keep base rate ≤ 1 kHz unless you know your timing budget.

2) Servo motor (SG90/standard RC servo)

Wiring

• Servo signal → D9 (or any “Servo”-capable pin), 5 V & GND from an external 5 V source (common GND).

Simulink blocks

• Standard Servo Write (or Servo Write) → pin 9.
• Drive it with Step / Sine Wave (mapped 0–180°) or a Slider Gain (0–180).

Notes

• Many servos draw >500 mA on movement — don’t use Arduino 5 V.
• If the block expects [0–1], scale angle: Angle/180.

3) Stepper motor (A4988/DRV8825 “STEP/DIR” drivers)

Wiring

• STEP → D3, DIR → D4, (optional) ENABLE → D2.
• VMOT (8–24 V typical) to driver; set current limit on the driver; common GND.

Simulink blocks

• Digital Output → DIR (D4) from a Manual Switch (0/1).
• Pulse Generator → STEP (D3):
• Amplitude = 1, Period = 1/fstep, Pulse width = 50%.
• e.g., 1000 steps/s ⇒ Period = 0.001 s.
• Optional acceleration: ramp the pulse frequency using a MATLAB Function block that outputs a time-varying period, or switch between multiple Pulse Generators.

Step round-trip

• For position, add an Encoder if your mechanics allow it; otherwise count generated steps in a Counter Free-Running block for open-loop tracking.

4) Closed-loop speed control (quick DC example)

Add:

• Analog Input (A0) → read a hall/optical sensor to measure RPM (or use an encoder).
• Edge Detector + Discrete-Time Integrator (or Counter + Rate Transition) to compute Hz/RPM.
• PID Controller block → output = duty (to PWM), input = (speed_ref — speed_meas).
• Run in External mode to tune Kp/Ki/Kd live.

5) Build, run, and tune

1. Monitor & Tune (External mode) to change sliders/gains live and watch Scope signals.
2. When happy, Deploy to Hardware for standalone operation (no PC).

6) Troubleshooting checklist

• Nothing moves: common GND? driver ENA pin asserted? correct pin numbers in blocks?
• USB resets when motor starts: motor supply back-EMF → add bulk cap near driver (e.g., 470–1000 µF), keep motor power off the Arduino 5 V, ensure diode protection (built-in on most drivers).
• Jittery servo: weak 5 V rail; try a dedicated 5 V/2 A BEC; keep signal wire short and away from motor leads.
• Stepper skips: current limit too low, accel too aggressive, or supply voltage too low.

Minimal block “recipes” (copy into a blank model)

DC H-bridge

• Slider (0–1) → Gain (0–255 if needed) → PWM(D5)
• Constant(1) → DO(D7), Constant(0) → DO(D8) (swap 1/0 to reverse)

Servo

• Slider (0–180) → Servo Write(D9)

Stepper

• Manual Switch(0/1) → DO(DIR=D4)
• Pulse Generator (Amplitude 1, Period 0.001, Pulse width 50%) → DO(STEP=D3)