Emotron 3000: Build an emotion meter circuit!

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If your child is like many other kids out there, they have trouble pinpointing their emotions and what they’re feeling. Today’s experiment not only helps with that but puts a fun and educational spin on emotions!

The Emotron 3000 emotion meter circuit experiment is a fairly simple circuit that works with a homemade dial. When the dial turns, it completes the circuit for one of the four LED bulbs, for which you can choose any emotion for the emotion meter. When the circuit completes for one of the LED bulbs, the LED lights up!

Ready to have your child identify those emotions with a fun circuit? Let’s do it!

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How to make the Emotron 3000 emotion meter circuit technology experiment

Supplies you will need

For this experiment, you will need the following:

• Cardboard box
• Copper tape
• Scissors
• LED lights, different colors (4)
• AA batteries (2)
• Battery holder
• Screw-on lid, small
• Tape
• Optional: paper and glue

Before you start

Two things: 1- we are playing with electrical components, so please watch your child.

2- If your copper tape rips as you are placing it on the paper/cardboard, don’t worry! Just start a new piece of copper tape and make sure it comes into contact with the ripped piece, then continue running it.

Instructions

Here is how to do this experiment with your child:

Step 1: Cut the cardboard and prepare the foundation

I chose to use a small cardboard box to house our emotion meter, but you can use a flat piece of cardboard as well. Cut it down to the size you would like your emotion meter to be.

In addition, cut a small rectangle of cardboard that is about 2.5″ by 4″. That rectangle will be for the dial.

This is also the time you can add a paper overlay on the cardboard if you would like one. I chose to add two pieces of white printer paper to the cardboard so it was easier to see the lights and the writing. I used a glue stick to adhere them to the cardboard.

Step 2: Power flow and the LEDs

Before we go further, I want to talk about the power flow for the circuit, since that’s an important part of the circuit!

In the schematic below, you’ll see I labeled the positive power flow with red and the negative power flow with black. Those are universally known colors associated with the flow of power. When you see dotted lines on the schematic, that means they are under something.

So in the image below, the black wire from the battery holder is running under the cardboard rectangle. The red wire from the battery pack is running on top of the cardboard rectangle but under the circular dial.

These are important because, when I designed this circuit, I made sure the positive and negative lines of power did not cross.

Now, onto the LEDs!

Identify the anode ( + ) and the cathode ( – ) of the LED. The anode is the longer leg of the two.

You’ll see in the schematic below how each of the four LEDs are aligned. Pay close attention to the side the anode and cathode is on for each bulb.

The next schematic shows how we will run the positive power flow and negative power flow (both using copper tape).

The final image shows the LED legs bent slightly and placed on the cardboard.

Step 3: Run the negative copper tape

In this step, we are only running the copper tape from the negative LED legs.

This is for two reasons:

1. We are keeping the negative and positive flows of power separated. If the lines of positive power flow and negative power flow cross one another in the incorrect spot, our circuit won’t work properly. This configuration allows us to run the negative power flow so it won’t touch the positive.
2. The negative power flow is going to stay beneath the cardboard rectangle we made in the first step, so we have to run this charge first.

Once you have located the anode ( + ) and cathode ( – ), you can begin! First, run a line of copper tape horizontally about 2/3 of the way down the cardboard/paper. Then, run a line of copper tape from the cathode of each LED down toward the horizontal line, making sure they come into contact with one another.

As I mentioned before: if the copper tape rips, don’t worry about it! Just start a new line of copper tape and ensure it comes into contact with the ripped piece.

Step 4: Tape negative wire from battery holder to the circuit

Now we’ll run the negative power from the battery holder to our negative copper wire.

I chose to place my negative wire off to the side a little bit to ensure it doesn’t come into contact with the positive copper tape later on.

To do this, simply place the exposed negative wire from the battery holder to touch the copper tape, then place another small piece of copper tape on top of it to hold it in place (creating a little copper tape sandwich).

Here’s what this step is doing: the copper tape is conductive, which means that power can flow through it. Without the negative wire of the battery holder connected, we have no power to flow. Once we place the negative wire from the battery holder between two pieces of conductive copper tape, we have a power source for our circuit!

Since we still do not have batteries in the battery holder or a positive flow of power, our LEDs will not light up just yet.

Step 5: Place paper clip through cardboard/paper for an axis point

In this step, we are preparing an axis for our dial.

Use a pencil or something similar to puncture a small hole through the cardboard/paper. The hole should run all the way through.

Then, unfold a small portion of the paper clip. The leg you unfold should be at a 90-degree angle from the rest of the paper clip.

Run the unfolded leg of the paper clip from the bottom of the cardboard through to the top, creating an axis. Tape down the paper clip on the bottom of the cardboard so it stays in place.

Step 6: Place cardboard rectangle on paper clip axis

Puncture a small hole in the middle of the cardboard rectangle you cut out in the first step. It shouldn’t be large; the size of the paper clip leg.

Place the cardboard rectangle on the paper clip axis, then run tape around it to hold it in place. Taping it down also helps when running the copper tape from the paper to the cardboard rectangle.

Step 7: Run the positive copper tape

Now it’s time to run the positive copper tape!

Run a line of copper tape from each of the anodes of the LEDs, making sure that you do not place any copper tape on the existing negative lines of copper tape (remember how I mentioned they can’t touch each other earlier?).

The copper tape from the anodes should run on top of the cardboard rectangle you placed in the previous step.

Again, if your tape rips, no worries! Just start a new line, ensuring it touches the old line.

The copper tape should run from the anodes to the top of the cardboard rectangle. Since the dial needs to come into contact with each of these positive copper tape lines, make sure that you run the copper tape toward that paper clip axis point (see image below).

Step 8: Prepare the dial

Puncture a small hole in the middle of your dial (the small lid or cap). This will fit over the paper clip axis, so the hole shouldn’t be large.

Run a piece of copper tape from the hole you puncture to the side of the dial and wrap the copper tape around the edge. This is so you can see where the copper tape is pointing since the dial will be placed with the copper tape facing down.

Step 9: Connect the positive flow wire (red) to the circuit

We’re going to make a copper tape sandwich again, but this time, for the positive power flow.

This time, we are not going to directly connect the positive power flow to the copper tape leading to the anodes.

This is because we want the dial to connect the positive power flow for us, depending on where we turn the dial.

Place some copper tape around the paper clip axis, making sure there is copper tape in every spot around the axis. The copper tape should even overlap a little, just to ensure there is touching copper tape all around the axis.

Next, place the exposed portion of the red (positive) wire of the battery holder on top of the copper tape, then place another piece of copper tape on top of it to hold it in place.

Finally, I taped down the red wire just to keep it out of the way.

Step 10: Place your dial on and turn on the Emotron 3000!

Place the dial copper tape down on the paper clip axis.

Insert two AA batteries into the battery holder and ensure that the tab is placed down on the holder.

Turn your dial to your emotion (might have to press down a little) and show us your emotion!

The technology behind the Emotron 3000 emotion meter circuit experiment

This experiment teaches:

• Basic circuits
• Being in touch with your emotions
• Fine motor skills

How it works

This experiment consists of four smaller circuits: one circuit for each emotion placed on the cardboard. We use LED bulbs for the lights, copper tape to transfer power, and a battery holder with AA batteries for the power.

None of the circuits are completed because we left a small hole in the positive power flow. We place a piece of copper tape under the dial that connects the positive power from the battery holder to the anode of the LEDs.

When we turn the dial so the copper tape joins one of the pieces of copper tape (connecting to one of the LEDs) to the positive power flow from the battery holder, the LED on our Emotron 3000 lights up!

Basic circuits

The Emotron 3000 experiment teaches about basic circuits by showing that, if a circuit is not completed (like when the copper tape does not fully connect to the positive power flow), then there will be no power supplied to the LED lights.

It also teaches how power flows through a circuit, from negative power in the battery holder to the cathodes in the LEDs, and positive power in the battery holder to the anodes of the LEDs.

Being in touch with your emotions

Once the circuit is built, it’s a great game to play with your child to figure out their emotions!

Some kids don’t want to talk about their emotions or don’t really know how to yet, but allowing them to use a fun light-up circuit like this puts a more exciting spin on talking about their feelings.

It’s also easy to change the LED bulbs for new colors, so you can add more emotions to the emotion meter at any time.

Fine motor skills

Bending the LED legs and running copper tape in a straight line requires fine motor skills, so this experiment is a good opportunity for your child to work on that skill.

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More experiments about building circuits to try out with your child

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• Is saltwater conductive? Build a saltwater circuit to find out!