Introduction: [02] Contactless IR Arduino Tachometer

Hello, I present my second proyect a contactless tachometer with graph included.

Inspired by Great Scoot's proyect and because I want to meausure the speed from some motors, I made this Tachometer.

Supplies

  • Arduino Nano
  • IR Distance Sensor
  • 128x64 OLED Display
  • Protoboard/Breadboard


Optional

  • LiPo Batery and Charge Board (I have scaveged from wireless earphones)
  • 3D printed Case

Step 1: Wiring

First step is to conect the modules:

  • - D2 to the IR sensor Output
  • - A4 to SDA and A5 to SCL
  • - 5V to VCC on both sensors
  • - GND to GND on both sensors


Step 2: Upload the Code

Second step is upload the code, in my case used ArduinoIDE:

I have used OLED_SSD1306_Chart by José Gabriel, and he needs Adafruit GFX library.

I have use too the code from Great Scot's tachometer too.


My screen have the adress 0x3C, usually is this or 0x3D, if neither work, you can try the i2c_scanner from the wires examples. You can read the adress in the serial monitor.

Step 3: Optional: Solder and 3D Enclosure

I soldered all in place and put it in a custom 3D printed enclosure.


To check the acuracy I used a metronome@120 BPM (youtube video) and my finger and it seems ok. I plan to make a stroboscope to double check this at higer speeds.

Step 4: To Do/improvements

The 3D printed enclosure have a lot of room to improve.

The code present some bugs, specially with the max value. But I think the graph show us much more info than a single number.

I wanted to add a switch to freeze the screen but I didn't have the hardware for that.


If you have a question leave it in the coments.