Introduction: Study Area Indicator (SAI)

Want to make it easier to find a study spot during finals week? Consider building study area indicators!

At its simplest, the system is a collection of Study Area Indicators (SAIs) connected to a main source of power that indicate the availability of a study space using the colors green, yellow, and red, meaning available, unoccupied, and occupied, respectively.

When the indicator is green, it means someone is sitting at the study area but is willing to let other individuals sit with them.

Yellow means no one is currently occupying the study area.

Lastly, red means that the spot is occupied and the resident is unwilling to invite others to their table.

If you are interested in making the system more convenient to find available spots at a glance, you can make an ambient display and numbered tiles which show all areas connected to an SAI and what tables they are based on the numbered tiles.

This particular system was designed to work with booths in particular (or any kind of study space set against a wall) as part of an Indiana University class on making for good! Credit for the creation of this design goes to Caiden Paauwe, Parker Weyer, and Evan Wright.

Below lists the full array of equipment and materials needed to build this project.


Components List

Study Area Indicator

-7 3D printed domes

-7 1/8'' laser cut white acrylic face plates (no holes)

-7 1/8'' laser cut white acrylic face plates (three holes)

-7 1/8'' laser cut white acrylic base plates (no holes)

-7 1/8'' laser cut white acrylic base plates (square hole)

-7 Lilypad Arduino Simple Boards

-7 Push Buttons (specific brand included in parts wishlist below)

-7 Adafruit Super Bright Green 5mm LEDs

-7 Adafruit Super Bright Yellow 5mm LEDs

-7 Adafruit Super Bright Red 5mm LEDs

Ambient Display

-1 1/8'' laser cut clear acrylic ambient display faceplate

-1 1/8'' laser cut white acrylic ambient display base (with etchings)

-7 Adafruit Flora Neopixels

-1 Adafruit Super Bright Green 5mm LEDs

-1 Adafruit Super Bright Yellow 5mm LEDs

-1 Adafruit Super Bright Red 5mm LEDs


-1 Arduino Due

-1 USB to plug converter

-7 Laser cut ¼” wooden numbered booth markers

-1 Coil of solder wire

-1 Sheet of wool (your choice)

-1 Copper Tape

-1 Sheet of paper

-1 Hot glue sticks

-1200 ft Wire 24 AWG single coil


-Soldering Iron


-Wire Cutters

-Hot glue gun

-3D printer

-Laser cutter


-Tape Measure

NOTE: You will need access to a 3D printer and a laser cutter for this project. Resources associated with those machines - PLA, acrylic, wood - are safest to use when using the resources provided by the company or workshop that provides the 3D printer and laser cutter. This is due to safety hazards associated with printing with or cutting with certain types of materials. Please be careful when using these machines. Similarly, the amount of these resources that you will need - acrylic and PLA - depend entirely on how many SAIs you want to build. Consult with the owner of the laser cutter and 3D printer you are working with to determine how much material you need for this project.

Step 1: Parts List Link, 3D Printing/Laser Cutting Files, and Code

This section includes the parts list, files, and code you need in order to construct this project.

Parts List

NOTE: This list does NOT include a comprehensive list of materials needed in order to laser cut or 3D print. Please consult with the workshop, school, or company who owns the 3D printer or laser cutter to decide on best materials.


Download the code and use a .zip file extraction tool such as 7Zip to access the code.Connect each Arduino Lilypad to your computer via the USB cable provided by the product.Drag and drop the code into each LilypadComplete the same downloading and drag and drop process for the Arduino DueMake sure to upload the code for the Lilypad Arduinos and Arduino Due before constructing each SAI. You can do so by dragging the appropriate code files directly into each product while it is plugged into your computer. You do not need the .ino file. Only download the other file in each folder.


All files are attached here. However, you will not need all the files at the same time.

The files with the key word "Ambient Display" will be used exclusively for cutting the Ambient Display.

The file entitle "Faceplate_Bottomplate" provides the top and bottom acrylic pieces for the SAIs that do not need holes.

"Faceplates with hole" provides the white acrylic pieces which you will lodge your LEDs in using hot glue.

"Bottomplates with hole" gives you the bottom part of the SAI where you will glue your push-buttons to.

The last file ending in .stl will be the one you use in order to print the 3D PLA domes for the SAIs.

Step 2: Safety Warning: Find a Partner and Be Safe

This project is relatively easy to follow but difficult to execute alone. It is recommended that you build this project with a partner in order to make the process easier.

Before beginning the project, make sure you understand the basics of circuitry, soldering, 3D printing, and laser cutting.

You should understand the difference between positive and negative, how to make a good soldered connection, and how to avoid accidentally poisoning yourself with toxic gas when laser cutting (yikes!).

Do not attempt to use a laser cutter or 3D printer by yourself without previous experience. Please seek help from a professional for laser cutting.

Step 3: Watch the Video

Due to the difficulty it takes to explain this design exclusively in writing, a video has been provided that describes the whole design process in detail.

For a better understanding of the system, please watch the attached video.

Step 4: Problem Statement

Finding an open study area can be difficult during finals. Our aim with this project is to make it easier to find an available area and make it feel safer and less rude to sit at a table with another individual that you do not know.

We aim to do this through technology facilitated social interaction. Most technology - such as Skype, Facebook Messenger, or Twitter - exclusively enable social interaction. Without it, we cannot communicate with one another. By facilitating social interaction with technology, we hope to enrich and encourage real-life interactions rather than make them possible over long distances.

But there is a gap in research and in design regarding facilitating technology. Very few designs specifically try to facilitate face-to-face social interaction rather than enable it.

We have designed this project with the hope to fill that gap and make it easier for students to find study areas.

This project was designed at Indiana University for the intent of relieving the stress of finding available study areas and make it feel less rude/more comfortable to ask if you can sit at a table with someone you do not know.

Step 5: User Interaction With the System

User interactions with the system are very simple. Users follow three basic steps:

1. Observing the ambient display

2. Selecting a table

3. Updating the SAI

NOTE: SAIs automatically turn to yellow after two hours in case users forget to update the system when they leave the study area.

Step 6: SAI Construction: Step-by-Step

    1. Begin 3D printing domes

    2. Laser cut all Study Area Indicator faceplates and baseplates

    3. Measure and cut all Study Area Indicator and Ambient Display wires

    4. Solder LEDs and push buttons to Lilypad Arduinos

    a. Solder the positive end of the red LED to pin 5 of each Arduino Lilypad

    b. Solder the positive end of the yellow LED to pin 6 of each Arduino Lilypad

    c. Solder the positive end of the green LED to pin 9 of each Arduino Lilypad

    d. Solder one end of the push button to pin 10

    e. Solder grounds for the red, yellow, and red LEDs and push button to the ground pin of each Arduino Lilypad (represented by the negative sign symbol)

    f. Finally, solder long wires (the size you want to stretch each SAI to the Arduino Due) to pins 11, A2, A3, positive (represented by a plus sign) and negative (represented by a minus sign). These are the information lines for the red, yellow, and green LEDs and power lines respectively.

    5. Hot glue Study Area Indicator faceplates together (no holes glued to three holes)

    6. Hot glue Study Area Indicator LEDs into faceplate holes

    7. Hot glue Study Area Indicator push buttons into baseplates (square hole)

    8. Hot glue small strips of wool onto the bottom of the Study Area Indicator baseplates (square hole)

    9. Hot glue Study Area Indicator baseplates (no holes) to the wool strips on the baseplates attached to the Study Area Indicator baseplates (square hole)

    10. Hot glue Study Area Indicator faceplates to the inside of the Study Area Indicator domes Hot Glue baseplates to the Study Area Indicator domes

    You are now done with your SAI construction! Next, we will move on to make the Ambient Display.

    NOTE: Sizes for the internal wires are variable. Only cut them long enough to reach from the pins on the Arduino to the LED that will be glued into the faceplate of the SAI. Make sure you check which side is positive and negative for the LEDs before soldering them to the Arduino Lilypads.

    Step 7: Ambient Display Construction: Step-by-Step

    1. Laser cut the white acrylic and clear acrylic pieces for the Ambient Display
    2. Gather 7 Adafruit Flora Smart Neopixels
    3. Gather wire
    4. Gather sheet of paper
    5. Gather copper tape
    6. Gather 3 Super Bright LEDs (one of each color)
    7. Create a positive (red wire in image) and negative parallel (black wire in image) circuit connecting all 7 Neopixels by soldering the connections
    8. Create an information circuit (white wire in image) connecting all 7 Neopixels by soldering the connections (make sure the directional arrows on the Neopixel are all going the same direction)
    9. Make sure all three lines extend beyond the Neopixel strip so they can connect to the next part
    10. Cut a small square of paper and create a parallel circuit on the paper using copper tape (easier than soldering the LEDs directly to the Neopixel parallel circuit)
    11. Align the Super Bright LEDs on the copper tape parallel circuit with green at the top, yellow in the middle, and red on the bottom
    12. Solder the LEDs to the copper tape. Make sure to match the positive and negative circuits to the path you created with the Neopixel strip
    13. Solder the parallel circuit from the Neopixel strip to the copper tape parallel circuit
    14. Attach the whole unit using a hot glue gun to the back of the white acrylic cutting for the Ambient Display
    15. Use a hot glue gun to attach the clear acrylic top to the front of the white acrylic display

    NOTE: The numbered etchings on the white acrylic may be difficult to see. There are two options for correcting this. The easiest way is to leave on the brownish sticker covering that covers the acrylic. The way the laser cutter will cut the acrylic will make it easy for you to salvage the stickers and use them as the sole image for each number on the sign (shown above in the example). Alternatively, you can use a black marker and scribble all over the etched areas of the white acrylic cutting. Afterwards, wipe off the excess on top and the portion of the marker that made it into to the etching will stay in place.

    DISCLAIMER: Laser cutting is very dangerous without the supervision of a trained professional. Please do not operate a laser cutter without training and proper ventilation.

    Step 8: Connecting SAIs to the Arduino Due: Step-by-Step Process

    Connecting all the SAIs to the Arduino Due is arguably the most difficult aspect of this project. These are the steps you can follow to connect the system.

    Parallel Circuits and Plugging in Ground and Power

    you must create at least two parallel circuits using your remaining wire if you plan to use more than 1 SAI at a time. Simply do this by cutting wire into small portions and expose the wire at both ends using wire cutters and then twist them together.

    1. Determine the number of SAIs you plan to use at one time

    2. Cut wire into pieces, twist them together to create "nodes" which you can solder Ambient Display and SAI ground and power connections

    3. Solder all positive wires for the SAIs and Ambient Display to one line of the parallel circuit

    4. Solder all ground wires for the SAIs and Ambient Display to the other line of the parallel circuit

    5. Connect the line of grounds to the Arduino Due by inputting the exposed wire directly into a spot that says "GRD" as demonstrated in the pictures above

    6. Connect the line of positives to 3.3 volts (shown in the picture above)

    Ambient Display

    1. Connect the information wire of the Ambient Display to digital pin 53

    2. So long as you have already connected positive and ground, all Neopixels should be displaying red


    1. For each unit, progressively connect the information wires to the due starting at pin 22 (red, yellow, green, repeat)

    a. Similar to the picture above, insert the red LED information wire in digital pin 22

    b. Insert the yellow LED information wire in digital pin 23

    c. Insert the green LED information wire in digital pin 24

    2. Repeat this same process increasing the pin number by 1, following the pattern red, yellow, green, for the information wires.

    NOTE: Plugging in more than 7 SAIs at one time is plausible, but difficult to do. It is advised that you do not plug in more than 7 SAIs for each Arduino Due.

    You have officially completed this Instructable! Congratulations!