Introduction: Make a Pressure Sensor for Wearables!
We’re going to make a pressure sensor! Pressure sensors give you the ability to control the amount of electricity that's flowing to your LEDs, just like a dimmer switch.
Follow this tutorial, featuring an extremely useful creative circuit material called velostat, and we’ll teach you how to make a circuit that senses pressure and changes the LED brightness accordingly. Hurray!
Creative Circuit Materials:
- pressure cloth (velostat)
- coin cell battery
- battery holder
- 3 alligator clips
- copper tape
- conductive thread
- thick paper or card stock
- sewing needle
- clear nail polish (recommended)
Step 1: Cut the Card-stock!
Cut two identical shapes out of the card stock. We chose rectangles, but you could do stars, hearts, moons, etc. Just make sure you make them 4in x 2in - or close to the size of your hand.
Step 2: Cut the Pressure Cloth!
Cut the black pressure cloth to make the shape of the card stock.
Step 3: Wrap Card Stock With Conductive Tape
Peel off the white paper backing from your conductive tape, but make sure not to let your tape curl up. Firmly press the copper tape down the middle of the card stock or loop it around. Repeat this on the other piece of card-stock.
Step 4: Tape Down the Pressure Cloth!
Tape the pressure cloth piece on top of the copper tape.
Step 5: Battery Holder
Put battery with positive-side up in the battery holder
Step 6: Alligator Clips - Part 1
Take a strand of alligator clips and attach one clip to the positive side of the battery holder. Attach the clip on the opposite end of the alligator clip to the copper tape on the top-side of the pressure sensor.
Step 7: More Alligator Clips - Part 2!
Take one strand of alligator clips and attach one clip to the negative side of the battery holder. Attach the clip on other side of alligator clip to the negative (shorter) leg of the LED.
Tip: When making a project, use different-colored alligator clips so that you can remember which alligator clip is ground and which one is connected to positive.
Step 8: Alligator Clips - Part 3!
Whew, time for the last clips!
Take one pair of alligator clips and attach one clip to the positive leg of the LED. Attach the other clip to the copper tape on the other side of your new pressure sensor.
Step 9: Let's Test!
Now, we’re ready to test the sensor! Push down on your new sensor. The more you press, the brighter the LED should get.
TIP: If it's not working double check that your alligator clips are connected correctly, and make sure your battery and LED are working by sliding the LED over the battery and seeing if it lights up.
If you want, you can replace the alligator clips with conductive thread to make a more permanent sensor, or to make a sensor that you can include in your clothing - think gloves or shoes that light up when you press them!