Introduction: Electric Unicycle Arduino DIY

This is a cheap electric arduino self balance unicykle. Total cost is around 360 USD, and you get a range of 10-15KM. The unicycle works like a Segway just with one wheel.

Step 1: Step 1. Parts

To make this you need:

i have bought all on ebay.

  • Unicycle 20" Tire 80 USD
  • Motor 4-600W DC brushed motor 100 USD
  • Old normal 21 gear bike(gears and chain) 10 USD
  • BTS 7960 40A 25V motor controller 25 USD
  • MPU 6050 gyro 5 USD
  • Arduino Nano V3 5 USD
  • LM2596 DC DC 3A 5 USD
  • 22.2V 10C 10000MAH Nano Mars Lipo 100 USD
  • iMAX B6 LCD battery charger 5A 20 USD
  • 80A fuse, on switch, main relay. 10USD.
    • Total 360 USD.

Step 2: Step 2. Drivetrain

Her you need a large 48 tooth crankset. Remove the smallest 24 tooth and attach the largest with rubber bearings. Because is really difficult to attach it dead senter. So when you attach the chain is will prevent it to slip out.

I have a 2600RPM motor.

20"*2,54(to cm)*3,14/100=1,59M/RPM.

And i have first 1:3(6-18) in the first chain, and 1:2,7(13-48) in the other. That gives me a total of 1:11.


That gives me a top speed of:

236RPM*1,59m*60Min/1000m(in 1 km)=22,5 km/h. But the software limits it to 70%. So 15 Km/h.

Step 3: Step 3. Electronics

The code is from a segway. Is Ovaltineo that has wrote it and you can fint it here:

I use a 24V 10Ah and its have 240Wh, and it rated at 10C. So it can deliver 2,4KW.

The motor controller can deliver 40A, 960W. And the motor i use is 600W.

You have to find a box of some sort to solder everything together. i have also installed a Horn, and light on it to be a legal "segway" in my country.

Step 4: