Introduction: The Love Tester

About: I used to teach middle school science, but now I run my own online educational science website. I spend my days designing new projects for students and Makers to put together.

Remember those cheesy "Love Testing" machines that used to be found in bars and restaurants? Now you can have all the thrills of using one of those machines in the comfort of your own home. Just in time for Valentines Days!

But in all seriousness, we figured this would be a simple and silly project that would entertain friends and family. We designed this project to be 100% soldering free, using only conductive tape and paper in the build process. Overall the project takes around an hour to put together with most of the work going into the paper design process.

You don't need any parts or supplies from Brown Dog Gadgets to build this, however if you do want to purchase supplies it helps us continue to create new projects and classroom resources.


Electronics Needed:

Craft Supplies Needed:

  • Cutting Tools (we used a Silhouette Cameo/ Cricut to help us out)
  • Glue and Tape
  • Paper of various colors
  • Foam Board or Foam Core
  • Adhesive Foam Dots (Optional)

Step 1: Cut Out All the Fancy Paper Designs

We wanted to make ours look really fancy, so we made up some designs in Illustrator and used our Cricut/ Silhouette Cameo to do the hard work for us. You can easily do much of the same things using a Pencil, some Markers, and Xacto Knife.

We attached a nice diagram to this Instructables Write up but you can download all the cut files, diagrams, and code at our GitHub Repo as well. (Since Instructables sometimes has issues with files.)

This project also scales up really well. If you wanted to you could build this on a large poster board or a wall. If you wanted to get super weird you could do this project on a shirt with either Maker Tape or conductive thread... but that might be awkward for other people...

Step 2: Cut Your Foam

The base and neck of the project are built using foam core to give everything strength.

It doesn't matter what color you use for foam core as we'll be covering it with paper later.

Cut one piece at a size of about 11 x 4 inches.

Cut another piece thats about 5.5 x 6.5 inches.

Step 3: Combine Your Foam

Measure about 2.5 inches in from the top of the smaller piece. Draw a line with a pencil.

Align the tall piece with that line and then trade around the tall piece.

Cut out that rectangle. Make sure the tall piece fits into the smaller base piece.

Step 4: Add Tape to the Base

The project is activated through a simple paper button that we construct.

First, place the two "activation" hearts onto your smaller base foam core piece. Align them to where you'll want them to end up, and then lightly trace around them with a pencil.

Place one piece of tape spanning the middle section of the board, and then run two parallel pieces of tape alongside it and around to the back. (If you want you can leave some extra tape hanging off the back, but it's not necessary. Maker Tape is conductive on top and bottom so you can just overlap new pieces of tape to make a solid connection.)

IMPORTANT: You want your tape lines close to each other but not touching. Leaving a quarter inch gap would be ideal.

Step 5: Cover the Base With Paper

Now that the base is wired up we need to hide it behind some nice looking paper.

Cut and wrap a piece of paper around the base piece. We used blue, but you can do whatever color you please.

Use a pencil to mark out where your folds and middle gap are. You'll also need to cut two holes in order for your switches to work. Those are the little H pencil markings on our paper.

Cut and fold everything.

Step 6: Wrap the Tall Foam

The tall foam piece holds our four LEDs. We'll need to get everything aligned and marked off so that our paper wrap matches our LEDs.

First, fold a piece of paper around the tall foam piece. We used silver paper for ours.

Next, find the center point of paper and draw a very faint line with a pencil from top to bottom.

Then, measure out four qual points along that pencil line for where your LEDs are going to be.

Use your LEDs to help cut out holes slightly smaller than your LED bulb.

Lastly, use a pencil and mark the foam behind the paper so you'll know where to put your LEDs.

Note: This is by far the most annoying part of the project. If you're at all having problems you can always just glue the paper to the foam and then poke the LED legs through the paper and foam. You'll still have your paper hearts to go over the top of them at the end anyways and it'll look just as nice.

Step 7: Wire Up the LEDs

IMPORTANT! LEDs have a Positive leg and a Negative leg. To make this project work you'll need to have all the Positive legs on one side and all the Negative legs on the other. This is an easy mistake to make but also an easy one to fix if you really have to.

Push your LED legs through tall piece of foam. It might be helpful to use a pin or knife to poke holes for each leg. Please make two holes for each LED, as the legs should never touch each other.

Fold one leg left and one leg right. In our short video and diagram the Negative legs are on our left side when looking straight at them.

Use one piece of tape and connect all the Negative legs together. Leave extra tape at the end.

Run a line of Maker Tape from each Positive leg to the bottom, making sure not to overlap tape or LED legs. Leave extra tape at the end of each one.

Maker Tape bends and folds very easily, so don't be afraid to make lots of twists and turns.

Step 8: Connect to Your Arduino and Upload Code

To connect your tape to your Crazy Circuits Board you just need to overlap it with the appropriate numbered circle. Just make sure you're not overlapping any other circles or liens of tape.

In our code we have this simple layout:

Pin 22 - Bottom LED

Pin 17 - Next LED

Pin 16 - Next LED

Pin 14 - Top LED

Pin 10 - Buttons

You'll also need to connect your Negative LED line of tape to the Ground pin (white circle hole) as well as the other line of your Button tape.

You can easily change which pins you're using in the code if you're using a different Arduino. To do this just change the numbers assigned to the LEDs and Buttons on lines 10-19.

As with any Arduino you'll need to upload the code. Download the Arduino IDE software as well as the Teensy LC add-on loader. In the Arduino Software choose Teensy LC as the board you're using. Copy and past the code into a new project window and hit Upload.

Step 9: Add Buttons and Test It Out

Throw a couple of overlapping strips of tape on the back of your #1 and #2 heart buttons. This is how we activate the lines of tape on the bottom of the project.

Plug your USB cable into your computer so that the Crazy Circuits Invention Board is powered on.

Put both hearts over their respective holes and press down. When both hearts are pressed down the circuit completes itself and the program runs. You should see the hearts light up.

If by chance you don't see that happening....

1) Check your connections. Especially is not a single LED turns on.

2) Is the project plugged in and powered on? Theres a small LED on the Invention Board that should be lit up when power is flowing.

3) Try uploading the code again. Watch the small LED on the Invention Board. When code is being uploaded it flashes to indicate that the files are being transferred.

4) Grab an alligator clip and connect it to our "button" pin 10. Touch the other end to one fo the Ground connections (the white circles on the board) briefly. See if that trigger things. If it does work that means your button circuit has an issue.

Step 10: Add Final Decorations

Once everything is confirmed to work, add the paper wrap to the rest of the foam and use a small amount of adhesive to hold it down.

Add hearts with sayings over each of the LEDs.

For the two heart buttons we used some small adhesive foam dots to add a bit of space between them and the tape below. You can accomplish this a number of ways using whatever crafting materials you have around.

We also added a the "Love Tester" sign to the top of the project in order to show off our amazing crafting skills.

Your project is now complete! Now go out there and spread love through ridged scientific testing!

Heart Contest

Runner Up in the
Heart Contest