Currently, unicycle is gaining popularity. What? Conveniently! It takes up little space, a large wheel “notices” road bumps less, a small contact patch with the road - less friction - less fuel (energy) consumption! That's just … All this has already happened …
I do not even want to write in what shaggy years have already come up with a way to mix "inside" one wheel. Since the days when they used engravings instead of photos!
The scale of such devices is evidenced by their availability.
Here is a woman rolling to herself, let us show imagination, in mmm "bunny"!
Promotional video:
A small child - not a reasonable one, uses this, for us, unusual transport. There is even a video with him on the network. (Well, as a video - newsreel) True, judging by the headphones, he chirped mercilessly!
There is already something similar to a gyroscope.
But these were done for several people.
And this topic has evolved! How do you like mono trains? Trains running on the same rail? Here's how, for example?
Or like this.
There are a lot of them! And with loads and people! If there was only one in all the photographs, it could be attributed to an unsuccessful invention, but there are many photographs, it means that such a technology took place and was used. I won't be surprised if in our time such a train is "invented":):):)
I never tire of noticing that all the main development is taking place exclusively in the field of digital technologies. Medicines are mass produced the same under new names. Cars - the same internal combustion engine that was a hundred years ago, only with a new body kit. We never flew into space - everything is spinning in the atmosphere … I tried to write about this here.