Update (4/29/2023) - below is a link to the STL files for recreating this project:
https://www.thingiverse.com/thing:599...

In this video I'll show how i made a powered gyroscope that can travel along a monorail or tightrope. I'll explain how angular momentum keeps the
gyro upright, even when gravity or other external forces try to knock it over.

The gyro uses an 8" diameter flywheel printed with PLA, with 21 1/2" steel bolts around the edge to dramatically increase the moment of inertia.

Some performance figures:

Motor KV: 620
Motor Voltage: ~15V
Motor Speed: ~9,000 RPM
Flywheel Speed: ~3,000 RPM
Flywheel moment of inertia: 0.0138 kg*m^2
Flywheel kinetic energy: 680 J
Flywheel angular momentum: 4.3 kg-m^2/sec
Drive motor speed: ~120 RPM

The drive motor has plenty of torque to climb a steep incline, but traction is a major limiting factor, so the best i could manage was 10-15 degrees on a tightrope. In the future, I'd like to build a rack & pinion rail for the gyro to travel on so that it can go up extremely steep inclines without a problem.

Hardware list:

3:1 GT2 Belt + Pulley set:
https://www.amazon.com/dp/B08QZ4365D

4S 1.3 Amp hour Battery:
https://www.amazon.com/1300mAh-Batter...

2-4S 30A ESC:
https://www.amazon.com/dp/B08K4LHQNZ

Servo tester:
https://www.amazon.com/HiLetgo-Consis...

The motor i used is out of production, but pretty much any other brushless motor of a similar KV will work fine.

Kevin MacLeod - Groove Groove
Eric Skiff - Underclocked
Kevin MacLeod - George Street Shuffle