Halloween is coming up soon and probably you need something to make the party a little bit more "scary"... This instructable consists of how to build a cheap and easy spooky pumpkin capable to sense the presence of a person and employ various spooky effects.

If you try to scare the pumpkin or even make a loud noise the eyes of the pumpkin will immediatly jump off and the inside will turn red instead of the initial light which is orange. And to add to that the Harry Potter theme will start playing to give you the ultimate spooky experience!

Step 1: HERE'S WHAT YOU NEED!

Here's what you need:

- 1 Arduino controller board.

- 1 breadboard.

- 1 fake pumpkin.

- 2 plastic eyes.

- 2 springs.

- 1 cutter.

- Hot melt glue.

- Bailing wire.

- 1 microphone sound sensor module.

- 1 passive buzzer. - 1 servo motor (SG90).

- Jumpers wire.

- LEDs.

Step 2: CRAVE THE PUMPKIN!

Cut out randomly spaced eye holes on the pumpkin with a sharp knife or a cutter with a diameter to accommodate both plastic eyes. Also, cut out a big circle on top of the pumpkin to access easily to the electronic part.

Step 3: EYES

Find the center of the back of the spooky eye and drill a small hole through it. Apply some hot melt glue inside the eye to increase a little bit the weight. Next, attach the springs to the back of the eyes taking care to have the spooky eye pupil centered.

Once the spooky eyes are mounted, place them in the eye socket and stick the springs to the pumpkin with hot melt glue and a piece of bailing wire.

Step 4: SERVO

To enlarge the servo motor, cut a piece of any kind of a resistant material and stick it aligned to the servo. Make sure the servo horn is correctly aligned with the piece.

Step 5: CONNECTIONS

Here's how everything is connected for it to work perfectly, feel free to change the pins if you need but remember to update the code if you do!

We can see that we have one input, that would be the sound sensor, which we connected only to the analogical port, and 3 outputs which are the LEDs (2 red and 2 orange), the servo motor and the passive buzzer which are all connected to digital ports.

Step 6: CODE

Here is the full code for the spooky pumkin, we used the Harry Potter theme from https://github.com/robsoncouto/arduino-songs/blob/master/harrypotter/harrypotter.ino but you can find a lot more songs already made on the internet.

So basically if the sound sensor detects a really loud noise it will change the color of the light inside of the pumpkin, as well as rotate the servo that will push the eyes out of the pumpkin. In addition to that the Harry Potter theme will start playing via a passive buzzer.

PROJECTEF.ino
Download

Step 7: PLACE EVERYTHING

Once all the connections are done, it's time to place all the components inside the pumpkin. Attach the Arduino board on a side using a double faced tape and place the breadboard in the bottom. Make sure the microphone sound sensor is near the mouth so it can detect the noise easily. Make a little hole in a side to pass the Arduino cable and pass it through it. Finally, place and stick the servo motor in a side of the pumpkin considering the movement it has to do. In this step, you need to be really careful with the positioning of all the electronics and cables.

Step 8: TRY IT!

CONCLUSIONS

This is a very easy project that allows you to get in touch with the basics of arduino as well as some fun components like the sound sensor and the passive buzzer that can produce melodies. Not only that, but you also learn the possibilities that you can achieve by coding and building these types of prototypes, and how useful a micro controller like Arduino can be.