Handheld Arduino LED Matrix Thermometer
Introduction: Handheld Arduino LED Matrix Thermometer
Made for ART3681C - Interactive Electronic Art
Supplies
Needed Supplies:
Most of the supplies I used were in this ELEGOO Arduino starter kit: https://www.amzn.com/B01D8KOZF4
* 1 - ELEGOO Arduino UNO R3 (included in kit)
* 1 - DHT11 Temperature and Humidity Sensor (included in kit)
* 6 - Male-to-Male Jumper Wires (included in kit)
* 1 - 9V Battery with Battery Clip (included in kit) or 1 - 5V Power Adapter (not included)
* 1 - 8 x 8 WS2812B LED Matrix: https://www.amzn.com/B088BTSPYD
* Thin Heat Shrink Tubing or Electrical Tape
* Arduino IDE (used to add code to the Arduino) https://www.arduino.cc/en/software
To add code to the Arduino, you'll need a computer nearby, and the USB cable that came included with the kit.
Optional Supplies:
I had leftover chipboard, Bristol board, and tacky glue to make a screen for the LED Array, but it's not necessary to complete the project. If you want to make the screen I made, you'll need a 3.5" x 3.5" square of any kind of thicker-pressed paper(Bristol board or cardstock are some examples),a small amount of chipboard, and tacky glue to make a frame for the LED Matrix.
Step 1: Prepare the Jumper Wires
To begin, grab six jumper wires. I recommend grabbing two red, two black, and two other separate colors, choosing four colors in total. After gathering the wires, you should notice that they have some rubber bits on both ends of them. We'll want to remove some of them by pressing the point of the jumper wire into the surface you're working on and holding onto the rubber part. They should come off rather easily, without ruining the wire. Do this on both ends to one red wire, one black wire, and one of the other colored wires. On the other three wires, you'll only want to remove one of the rubber ends, instead of both. We want to remove some of these so that we can connect everything together while also maintaining a lower profile on the finished product.
Step 2: Start Connecting the DHT11 Sensor
Grab the DHT11 Temperature and Humidity Sensor from the Arduino Kit, the three wires that have both rubber ends removed, and some heat shrink/electrical tape. The sensor should look like a blue box with holes, connected to a tiny circuit board with three leads coming from the board. Hold the sensor so that the blue is facing you, and the leads are pointing down. In this orientation, the leads in order from left to right are Data, Power(5v), and Ground. 769
We'll want to connect a wire to each of the leads on the sensor. I recommend using red for Power, black for Ground, and whichever other color was chosen for Data.
With Heat Shrink:
1. Add the thin-sized heat shrink to a end of jumper wire.
2. Put one of the leads of the sensor in the heat shrink and make sure that the wire end and lead touch a decent bit.
3. Warm the heat shrink so that it collapses around the wire end and lead, making a connection between the two.
4. Repeat for the other two leads.
With Electrical Tape:
1. Wrap a tiny bit of electrical tape around the end of a jumper wire.
2. Put one of the leads of the sensor on the tape and make sure that the wire end and lead touch a decent bit.
3. Press the tape around the lead and wire, making sure that the connection is solid.
4. Repeat for the other two leads.
Once you have the wires connected firmly with the leads, take the other point of each wire and bend them 90 degrees. You might have to add heat shrink or tape to the other end, as the wires sit close together on the Arduino, and having them touch might cause shorting.
Step 3: Start Connecting the LED Matrix
Grab the LED Matrix, along with the other three wires, these being the ones where only one rubber end was removed. The LED Matrix has several wire coming from it, two sets of red/white/green wires, and one red/black pair of wires. We only care about one set of the red/white/green wires, specifically the one that's labeled Power/Ground/DIN(Data In). 611