diy electric one-wheeled vehicle

Description

I recently got my hands on a used E-scooter wheel hub motor. Without any deep thoughts on the details of this challenge, I decided to build a simple one-wheel. To avoid buying batteries that would be for nothing in case I will not be able to ride this contraption it will use standard cordless-drill batteries (18V Li-Ion) I already have.
So far, all I have is a quick design idea made up with fusion 360.

Normally I would not share this kind of "just for fun" project but I thought it could fit the Reimagine Supportive Tech challenge. In the best case, the outcome is a modular, easy-to-build one-wheel platform. If it gets too complicated, expensive, or dangerous to ride I will change my plan and convert it to an e-scooter.

Details

For the start, I sketched up a curse schematic of the code, electronics, and power distribution the board needs:

The Idea is that a gyro will input the current angle of the board to an Arduino mega. The Arduino will then calc an appropriate control voltage for the motor controller. However, with the motor controller, I selected it will not be possible to make it completely self-balancing. I try to keep it simple: "lean forward" -> "increase control voltage" //"lean forward to much" -> "stop motor" ?

BOM:

Gyro: GY-521 MPU6050

Arduino: Mega 2650

DAC: MCP4725 12Bit I2C

MC: Generic Brushless Controller 36V / 48V 350W

Motor: Keenso 10-Zoll-Radnabenmotor

Batterie: Li-Ion, 18 V, 2x 2,5 Ah

I already think this ding will be extremely difficult to ride for me. (I am not exactly a sporty person. Like a surfer or snowboarder)

Project Logs

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new plan -> electric wheelbarrow
stefan.schnitzer • 03/10/2024 at 16:23 • 0 comments

I made a new, stronger spacer for the rubber tyre. My new plan for this motor is to build an electric wheelbarrow.
The scooter is still a prototype, but I already had my first flat tire.
stefan.schnitzer • 05/01/2022 at 13:36 • 0 comments

The scooter is still a prototype, but I already had my first flat tire. I fitted the hub motor with an airless tire to ensure this would not happen again. But the hub had to be turned down in diameter to match the tire.
To ensure that the tire does not slip off during a ride, I made a 3d-printed rim extension.
Almost ready for the summer...
More updates will follow...
stefan.schnitzer • 08/08/2021 at 06:47 • 0 comments

After some very unsuccessful attempts to drive the one well, I had to do admit that I am not a one-wheel driver. So I did the most reasonable thing and bolted it to a kid's scooter. More updates will follow... 😁
batterie holders and sanity check
stefan.schnitzer • 08/04/2021 at 17:41 • 0 comments

I 3D-printed two batterie holders and made a quick "sanity check" of the drivetrain functions.
The batterie holders are a modified version of this design on Thingiverse: https://www.thingiverse.com/thing:2976266
mechanical assembly
stefan.schnitzer • 08/02/2021 at 16:29 • 0 comments

I build the frame out of scrap metal and mounted the electronics on the underside with zip-ties and Kapton-tape.
In theory, it would be ready to ride, but it's raining outside and I think it's fair to say that my assembly is not watertight yet. 😁
quick update
stefan.schnitzer • 08/01/2021 at 13:54 • 0 comments

The electronics are ready...

...now it's time to build the mechanical assembly.
First run (of the motor)
stefan.schnitzer • 08/01/2021 at 05:11 • 0 comments

Thanks to a quick google search, I got the basic function to work. On the scope, you can see the control voltage for the motor controller. I used the code from https://github.com/fungineers-youtube/DIY-Onewheel-Arduino-Code and modified it.
The wheel hub motor changes speed according to the gyro input angle. (and makes a very satisfying sound)