ELISAVA Halloween Project

We are three ELISAVA students, a design and engineering school in Barcelona. We did this as a Halloween project for university. Our project consists of a framed portrait picture with two eyes that look at you and light up if you pass in front of the image. This is achieved through several hardware and software setups.

Halloween material

• 2.5m Pine Wood Slat (30 x 9mm) serveiestacio.com

• Printed picture to put in the frame ( In our case we printed a DIN A1 sized picture)

• MDF Wood Board (800 x 600 x 4mm) serveiestacio.com

• x2 Atrezzo Eyes partyfiesta.com

Arduino material

Practically all the components used for our project can be found in this Arduino Kit (amazon.es). However, only one unit of each big component is included in the kit so additional components such as protoboards or servomotors should be bought for this project.

• x3 Protoboards diatonic.com

• x2 ultrasonic sensors (HC-SR 04) diatonic.com

• x2 180º ServoMotors diatonic.com

• x2 red LEDs diatonic.com

• x1 8 Ohm Speaker diatonic.com

• x1 Battery

• Cables diatonic.com

The first step of our project was selecting and printing an image in a DIN A1 (594 × 841 mm) photographic paper. We chose a Carles Puyol portrait as we consider him an important Spanish celebrity. In order to make it spookier we made the image black and white. Before attaching the image with its support we made them fit so we cut the wood board to a width of 594mm and we cut the image to a height of 800mm. We then glued the picture in the MDF wood board using an adhesive spray.

The following step was making the frame. In order to save money, as we didn't want to buy a conventional pre-made frame for our project, we made it ourselves. We cut the pine wood slat in four using as guide measures the ones obtained in the previous step of the process, so we cut two 800mm slats and two 594mm slats. For them to fit with each other we made a 45º angle on each side (as shown in the first picture) to be able to create 90º corners for the frame. Afterwards we glued the frame with the picture and its support. We used both silicone and nails for attaching them together as using only silicone wasn't a viable solution.

Once the structure of the project was built, we had to drill it in order to be able to install the mechanism for moving the eyes and to enlighten them. We drilled a little hole used for passing the LED cables through the wood board and a bigger rectangular-shaped hole which enables the movement of the eyes through the activation of the servomotors located behind the image. We then built a support structure for these servomotors as they had to be located at a specific height, otherwise, the eyes would not be able to move. This support would also be used for the Speaker. Just below this support we built another one where the electrical components would be attached. This support is divided in three main areas; the protoboard, the Arduino and the battery. We built little walls in order to prevent the components from moving. However, we glued them to the support for greater security. These supports were made with scraps of the pine wood slat used for the frame.

Then we carried out the electrical setup and the Arduino program. On the one hand, as our goal was to move and light up the eyes once the ultrasonic sensor detected movement we had to use three protoboards; one for the eyes and two for the sensors, which had to be located at both sides of the picture. The main protoboard is the one located in the electrical components support and velds the connections for the speaker, servomotors and LEDs. The other protoboards held the connections for both the ultrasonic sensors. On the other hand, our Arduino program had to be able to detect if there is something in front of the sensors and, if detected, the servo motors should move certain degrees, the LEDs should light up and the speaker should make a selected sound. The working code is attached below.

The last step of our project consisted on connecting all the components to both the protoboard and the Arduino and making sure that we hardware and the software worked correctly. We drilled an LED-sized hole in the eye pupil in order to fit the LED in the eye and we connected its cables to the hardware. We also glued little wooden sticks to both the servomotors and the eyes in order to maintain them at the eye height and consequently enabling the movement of the eyes. We lastly connected connected the servomotors, speaker and sensors to the protoboard and the Arduino and we ran the code to check if it worked.

Once all the steps were done, we just had to set up the project for it to work when people walked in front of it. We connected the Arduino to a battery and hung the frame as if it were a paining. The sensors were located at approximately 40cm on both sides of the frame.

It has been a very fun and interesting project to work on. In addition, this project has helped us with understanding how Arduino works and how different inputs can result in a wide variety of outputs.