Flying Gamera Hat w/ flame jets & screech using Arduino for turntable & audio control

the demo video:

https://youtu.be/MbkvrJ_av2w

We all know Gamera, kaiju guardian of the universe and protector of children.

This Halloween inspired hat emulates Gamera flying, spinning on a turntable, radioactive flame jets firing from the shell's arm and leg holes.

A magnet inside Gamera is read by a Hall effect sensor.

As the magnet passes the sensor, the Arduino is counting rotations.

On a random # of rotations, Gamera will pause spinning with his head facing forward (home position) and roar.

After the roar, it will return to the spinning condition.

• Gamera's head is 3D printed.

• The body sides are cardboard with a foam covering, mounted on a plastic sheet. The sheet has holes in the center for bolting down Gamera's body to the gearmotor coupling.
• The hat has separate power switches for the turntable, and another for Gamera's flames.
• The turntable also has a hidden but easily accessible N.O. pushbutton to start/stop turntable rotation.
• Gamera's roar is saved to a ISD1820PY board. The 1820 has a speaker output, so I used a hi bandwith balun as an audio isolation transformer to the LM386 audio amp since the amplifier module is expecting a DAC input grounded on one side.
• Since the turntable doesnt reverse direction, rather than connect an H bridge to the Arduino, a single MOSFET is used,

which still can provide PWM speed control if desired.

• Code and schematics attached

/*

  GameraArduinoTurntable.ino

debugging code is left in, but commented out

*/

int HomeSwitch=LOW;

int HomeSwitchOS = LOW;

int HomeSwitchLastScan=LOW; 

int TurntableMotorON = LOW;

int TurntablePausePB = HIGH;

int TurntablePausePBLastScan = HIGH; 

int HomeSwitchCnts =0;

int HomeSwitchCntsTarget =0; // # of counts to accumulate before autopause the turntable

int AutoPause= LOW;

void setup() {

  //start serial connection

// Serial.begin(9600);

  //configure pin 2 as an input and enable the internal pull-up resistor

  pinMode(2, INPUT_PULLUP); //Pause spin pushbutton

  pinMode(4, INPUT); //Home position hall ellect switch

  pinMode(8, OUTPUT); // play audio output

  pinMode(11, OUTPUT); // turntable motor ON

  pinMode(13, OUTPUT);

  randomSeed(analogRead(0));

}

void loop() {

  //read the pushbutton value into a variable

  TurntablePausePB = digitalRead(2);  // HIGH is PB not pressed

  HomeSwitch = digitalRead(4); // HIGH is home switch active

//  THIS IS THE TURNTABLE AUTOPAUSE CODE BASED ON A RANDOM number of spins  

  if ((HomeSwitch == HIGH) && (HomeSwitchLastScan== LOW))

    {

      HomeSwitchOS == HIGH;

      HomeSwitchCnts = HomeSwitchCnts + 1;

     }

    else

    {

      (HomeSwitchOS == LOW);    

    }

   // if (HomeSwitchOS==HIGH)

   //  { HomeSwitchCnts = HomeSwitchCnts + 1;} // counting Homeswitch passes

   delay (10); // catch up

  // Serial.print(" HomeSwitch == ");

  // Serial.print(HomeSwitch);

//  Serial.println ();   

  // Serial.print(" HomeSwitchLastScan ");

//   Serial.print(HomeSwitchLastScan);

//  Serial.println ();   

//  Serial.print(" HomeSwitchCnts = ");

//  Serial.print(HomeSwitchCnts);

//   Serial.println ();

   HomeSwitchCntsTarget=random(5,40);

   if (HomeSwitchCntsTarget<HomeSwitchCnts)

    {  AutoPause=HIGH; }

    else { AutoPause=LOW;}

//   Serial.print(" HomeSwitchCntsTarget = ");

//  Serial.print(HomeSwitchCntsTarget);

//   Serial.println ();

  delay (10);

//  DONT FORGET TO ADD CODE TO RESET HOMESWITCH CONTER , add code to stop on counts

// TURNTABLE CONTROL CODE ///

            if ((TurntablePausePB == HIGH) && (TurntablePausePBLastScan==LOW)&& (TurntableMotorON == LOW)) //means PB was pressed, run the turntable motor

              { TurntableMotorON = HIGH;

                TurntablePausePBLastScan=TurntablePausePB;

                delay (100);     // debounce

              }

            if ((TurntablePausePB == HIGH) && (TurntablePausePBLastScan==LOW)&& (TurntableMotorON == HIGH)) //means PB was pressed while running, stop the turntable motor

              { TurntableMotorON = LOW;

             // TurntablePausePBLastScan=TurntablePausePB;

                delay (100);     //debounce

              }

            digitalWrite(8,AutoPause); // turn on output to trigger soundplayer

            digitalWrite (13,AutoPause);

            if ((TurntableMotorON == HIGH)&&(AutoPause==LOW))

              {

              digitalWrite(11, HIGH);

               }

            else {  digitalWrite(11, LOW); // pause turntable for 10 secs, play audio , zero home switch counts

                   if (AutoPause==HIGH)

                    { delay (7000);

                    HomeSwitchCnts=0;

                    AutoPause=LOW; }

                }

              //Serial.print(" TurntablePausePB = ");

   //Serial.print(TurntablePausePB);

  // Serial.println ();

             //Serial.print(" TurntablePausePBLastScan = ");

  // Serial.print(TurntablePausePBLastScan);

  // Serial.println ();

//        Serial.print(" TurntableMotorON = ");

   //Serial.print(TurntableMotorON);

  // Serial.println ();

//      Serial.print("AutoPause = ");

//  Serial.print(AutoPause);

//  Serial.println ();

   // digitalWrite (13,TurntableMotorON);

  TurntablePausePBLastScan=TurntablePausePB;

  HomeSwitchLastScan=HomeSwitch; // update last scan status

}

Here are some of the progress pix while building the Gamera hat and testing HW & SW.

I really really appreciated using the nice test equipment won in previous E14 project competitions.