The Tentaskull, an idea evolving out of a failed attempt at another project, combines the perfect amount of unsettling music with grotesque imagery. The project is made out of recycled Halloween props which were bought in previous years (The Skull), 3d Printed materials (the two tentacles), and finally Arduino components and code. It's a great project to do if you are a beginner or looking for an easy side task.

Step 1: Materials

1. Plastic Skull

2. two 3d printed tentacles

3. two Servo motors

4. two LED lights (any color would work)

5. three jumper wires

6. four 4-pin JST wires

7. one push button

8. one bread board

9. one grove sound recorder module

10. one speaker

11. two grove LED lights modules

Step 2: Code

1. This is my code for Arduino I recommend structuring it however you would like in order to understand it the best. It defines all variables and creates functions. If you don't understand coding or Arduino there are instruction's online and in books, but meanwhile this is the code you should use for this project ( apologies if when I transferred it over a few errors arose.

#include <Servo.h>
Servo srv;

int buttonState = 0; void setup() { srv.attach(6); // servo attached to pin 6 takes signals between 1400 and 1600

pinMode(2, INPUT); pinMode(3, OUTPUT); pinMode(4, OUTPUT); pinMode (8, OUTPUT);

} void loop() { buttonState = digitalRead(2); if(buttonState == HIGH) { srv.write(180); digitalWrite(8, HIGH); delay(1000); srv.write(0); delay(500); digitalWrite(3, HIGH); srv.write(270); delay(100); srv.write(180); delay(500); digitalWrite(4, HIGH); srv.write(91); srv.write(0); srv.write(150); delay(1000); srv.write(45); delay(500); delay(1000); srv.write(0); delay(500); digitalWrite(3, LOW); srv.write(270); delay(100); srv.write(180); delay(500); digitalWrite(4, LOW); srv.write(91); srv.write(0); srv.write(150); delay(1000); srv.write(45); delay(500); delay(1000); srv.write(0); delay(500); digitalWrite(3, HIGH); srv.write(270); delay(100); srv.write(180); delay(500); digitalWrite(4, HIGH); srv.write(91); srv.write(0); srv.write(150); delay(1000); srv.write(45); delay(500); digitalWrite (8,LOW); } if (buttonState == LOW) { srv.write(94); digitalWrite(3, LOW); digitalWrite(4, LOW); digitalWrite(8, LOW); } }

Step 3: Tentacles, Servomoters, and Breadboard

1. The tentacles can be 3d printed on virtually any machine. They are about 4.5 inches in height and about a 1 inch diameter

2. they can be made using Fusion 360 and if need be found on Thingiverse.com under a quick search of the keyword tentacle (I did not create them, still an amateur designer)

3. Next you need to find two servomotors and make sure their centers are set on the right degree measure, this means where (when power is going through the Arduino) the Servos are stationary (see code for my center, it's usually around 90. Glue the tentacles to the motors.

4.Next you need to connect the Servos to a breadboard; you can do this using a three prong connector piece.*Refer to the picture for placement, in order for the two motors to function properly during rotation they need to be lined vertically (the servo motors are connected to the black white and red wires) one directly infront of the others and both directly in front of the jumper wires.

5. Lastly you need to connect the Breadboard to the Arduino, this can be done with the jumper wires. When You take a look at the wires connected to the servo motors you may notice three different color: Black, Red, White. Black is connected to Ground, Red is power, and White is signal.You do the connections through the jumper wires hence their placement in the picture (on your adruino it should be labeled for grd, 5 volt poer and signal, which according to my code is 6.

Step 4: Music/ Sound

1.The first stand alone picture is that of a Grove Sound Recorder Module, its function is to enable you to add sound affects to your Arduino.

2. Connect the speaker to the port in the GSRM and then connect your GSRM to any port in the Arduino (make sure your Arduino is plugged into a computer or power source), this is to allow you to record what you would like into the speaker. No code is needed for this part so I recommend not uploading any code until this function is complete.

3. Keep pressing the push button on the GSRM until the light is flashing this is when you can now begin to start recording music or sound. I recorded Tiny Tim's "Tip Toe Through the Tulips" because I think it is sort of eerie; This compliments a skull with tentacles spinning out of it's eyes quite nicely, but anything will do.

4. Lastly refer to the photo where to place the wire if you are using my code (D8) or place it where ever you set it in your own

*5 the other wire plugged in to the Arduino are for future steps and will be covered later (I photographed it differently than I wrote the steps)

Step 5: PushButton

Congratulations! the steps are much easier form here on out

1. As seen in the code, the push button is the only input through out the entire design. This means the Arduino is taking in information instead of giving it away. The button is used to regulate the state of each object (when you push the button everything turns on)

2. Connect the button to the correct port. For my code it is D2

Step 6: Lights!

1. For this step I added two Led lights and connected each one to a grove LED light module

2. Next using JSL wires i connected each to a port according to my code D3 and D2 (the lights are interchangeable)

Step 7: Complete Arduino

1. This is what your now finished Arduino should look like. All that is left is the structure!

Step 8: Skull Breaking

1. Take your skull prop and being to cut out the eye sockets (I don't have the picture but most props don't have very big holes in the eyes). Make sure you have plenty of room for turning the Servos and tentacles. Also cut small slits in the nose to stick the LEDs out of.

2 Next flip the skull upside down and cut open the bottom, make sure there is plenty of room to fit all materials into and your hand to set them in place.

3. download the code onto your Arduino and fill the skull with all components, I glued the the servos in place so they would not fall out and taped down the rest

That's all Hope this was helpful and enjoyable to make