MK85 Motorized Helmet Wiring and Code

#include <Servo.h>

// MK85 basic Nano controller:
// - 2 servos for the faceplate
// - LED eyes
// - 1 pushbutton to toggle open/closed
// - No dimmer

const byte HEAD_SERVO_PIN = 9;
const byte FACE_SERVO_PIN = 10;
const byte EYE_LED_PIN = 6;
const byte BUTTON_PIN = 2;

// Starting angles from the MK85 servo setup.
// Adjust these in small 1 or 2 degree steps if needed.
const int HEAD_SERVO_OPEN_POS = 20;
const int FACE_SERVO_OPEN_POS = 160;
const int HEAD_SERVO_CLOSE_POS = 160;
const int FACE_SERVO_CLOSE_POS = 20;

const byte EYES_OFF = 0;
const byte EYES_ON = 255;

const int STEP_DELAY_MS = 12;
const unsigned long DEBOUNCE_MS = 60;

Servo headServo;
Servo faceServo;

bool faceplateOpen = false;
bool lastButtonReading = HIGH;
bool stableButtonState = HIGH;
unsigned long lastDebounceTime = 0;

void setup() {
  pinMode(BUTTON_PIN, INPUT_PULLUP);
  pinMode(EYE_LED_PIN, OUTPUT);

  headServo.attach(HEAD_SERVO_PIN);
  faceServo.attach(FACE_SERVO_PIN);

  closeFaceplate();
}

void loop() {
  bool reading = digitalRead(BUTTON_PIN);

  if (reading != lastButtonReading) {
    lastDebounceTime = millis();
  }

  if ((millis() - lastDebounceTime) > DEBOUNCE_MS && reading != stableButtonState) {
    stableButtonState = reading;

    if (stableButtonState == LOW) {
      if (faceplateOpen) {
        closeFaceplate();
      } else {
        openFaceplate();
      }
    }
  }

  lastButtonReading = reading;
}

void openFaceplate() {
  moveServos(
    HEAD_SERVO_CLOSE_POS,
    HEAD_SERVO_OPEN_POS,
    FACE_SERVO_CLOSE_POS,
    FACE_SERVO_OPEN_POS
  );

  setEyes(EYES_OFF);
  faceplateOpen = true;
}

void closeFaceplate() {
  moveServos(
    HEAD_SERVO_OPEN_POS,
    HEAD_SERVO_CLOSE_POS,
    FACE_SERVO_OPEN_POS,
    FACE_SERVO_CLOSE_POS
  );

  setEyes(EYES_ON);
  faceplateOpen = false;
}

void moveServos(int headStart, int headEnd, int faceStart, int faceEnd) {
  int distance = abs(headEnd - headStart);

  for (int i = 0; i <= distance; i++) {
    int headPos = map(i, 0, distance, headStart, headEnd);
    int facePos = map(i, 0, distance, faceStart, faceEnd);

    headServo.write(headPos);
    faceServo.write(facePos);
    delay(STEP_DELAY_MS);
  }
}

void setEyes(byte brightness) {
  analogWrite(EYE_LED_PIN, brightness);
}

const int HEAD_SERVO_OPEN_POS = 20;
const int FACE_SERVO_OPEN_POS = 160;
const int HEAD_SERVO_CLOSE_POS = 160;
const int FACE_SERVO_CLOSE_POS = 20;