Scary Teddy

The project we have below, set on Halloween, is about a teddy bear that tricks. On the outside, it looks very cuddly, soft, and cute, but on the inside, it's the opposite. Don't get too close or you'll get scared!

It consists of a teddy bear sitting with a box of candy to attract people. The box also has different lights that change color to make it more attractive. The bear has RGB LEDs in the eyes that change color the closer you get to the bear, from blue to red. Once you get too close the bear's head opens backward and spiders come out to give you a good scare.

Materials:

- Teddy bear

- Plastic spiders

- Fake spider cobweb

- Box of DM

- Candy

- Black spray

- Hinge

Electronic components:

- Arduino UNO

- Long and short wires for Arduino pins

- 3 LEDs (green, blue and yellow)

- 2 LEDs RGB

- 1 ultrasonic sensor HCSR04

- 2 Servomotor

- 3 Resistors

- 1 Button

Tools:

- Soldering iron

- Hot glue

- White glue

- Drill

- Screwdriver

First of all download the Arduino application on your laptop and configure the library we choose, HCRSR04 from gamegine, in order to install it. Save the two files in the same folder and open the Halloween file. Connect the Arduino UNO to your computer and load the code into it.

We bought a teddy bear and cut off its head, we emptied the body of the teddy bear to make room for the Arduino and different components.

We made a hole in the front and back to pass the wires, in the back the wires that are connected to the power and in the front the wires that are connected to the sensor, the LEDs and the button.

We cut 5 pieces from a DM panel to make the candy box that would go in front of the bear. Once cut, we had to make 3 round holes in the front piece to put three colored LEDs and two holes to fit the sensor. For the back piece, we have to make a hole for the wires to come out. Once all the pieces are well cut we hook them with white glue and paint everything black. Except for the back piece that we leave without putting it until the end. 

Now it's time to install the LEDs, one each of green, yellow and blue. And the sensor and check that everything works. 

Finally, we decided to incorporate a push button that will serve to secure the whole process so if you want to pass without a scare you can.

Now it's time to incorporate all the components of the bear, such as the eyes, which are two RGB LEDs that change color depending on where you are. When you are far away the color is blue and the closer you get, the more it intensifies until it becomes red. 

To make the mechanism of the head, we put cardboard in the back, and one in the head and together with a hinge we could put a servo motor to open and close it.

With the help of another servo motor, we hooked a pair of spiders to a wooden stick painted black to make it look like they were coming out of the bear's neck.

t's time to connect all the leds, sensors, buttons and servo motors to the arduino and place it inside the bear so that it is collected. 

To finish the project we decorated the bear with a few more spiders and some cobwebs to set the mood.