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Build Your Own Self-Balancing Unicycle
CaptainKaos[DOH!] writes "Robot hacker Trevor Blackwell is at it again, this time with a self-balancing Eunicycle. Blackwell writes, 'Some time ago I built a self-balancing two-wheeled scooter. Since then I realized that two wheels are redundant, and only a single wheel is needed to make a ridable vehicle. A vehicle with a single wheel is much smaller and lighter. It weighs under 30 lbs and is easily carried with one hand when going up stairs or on public transportation.' Trevor's previous 'Segway' type two-wheeler was mentioned on Slashdot."
You can find a torrent for the video here: Park-all.lowbw.mpg.torrent
RTFW $1500 for parts. It looks kind of cool, only I'm pretty sure it takes more skill to ride one of these than a Segway. I can just imagine all the bumps and bruises people would get on these things. The guy in the video has to have his arms out for balance all the time.
cool--what this guy has built is similar in nature to the 'bombardier embrio' concept motorbike.
articles with pics here and here
I use "Robot Power" speed controllers and "Battlepack" batteries in several of my bots...
In the book the pigs say "4 legs good, two legs bad", in reference to animals having four legs (good) and humans having 2 legs (bad).
If you read the article, you will see that this is more of a semi-Segway. It is *NOT* self-balancing. It's still a unicycle, and you still need to know how to ride a unicycle and keep your balance.
What this does do is use a gyroscope and sensor to detect when the rider leans forward or backwards and then accelerates or decelerate the wheel.
It's still a really neat contraption, though.
Elrond, Duke of URL
"This is the most fun I've had without being drenched in the blood of my enemies!"-Sam&Max
Now put a motor and battery on that bike. You'll be lucky to get under 50lbs.
http://66.102.7.104/search?q=cache:4K9GC46wUkAJ:tl b.org/eunicycle.html+&hl=en
Google Cache
Turning by leaning does require gyroscopic force, but not in the way you describe. It is required to allow you to change your center of gravity by leaning. On a bike with no centrifugal force (a stopped bike), you cannot change your center of gravity by just leaning without turning the handlebars. If you could, it would be easy to sit upright on a stopped bike.
When gyroscopic force enters the equation, it does allow you to change your center of gravity by merely leaning your body. Once you lean to the right and move your center of gravity to the right, you start falling over to the right. The reason you don't fall over completely is that the wheel also turns to the right of its own accord, which turns you and brings it back under the moved center of gravity. But the main reason for the turning not gyroscopic force; the real reason is the fact that the turning axis for the front wheel is not vertical. This means that when the bike is leaning to the right, the front wheel has a natural tendancy to turn right, even when stationary. Imagine a bike on its kickstand; the wheel is always turned in the direction of the lean, right? That's not a coincidence. This is the reason why you will never see a bike with a straight vertical rod connecting the front wheel to the handlebars. (or if you do see one, it will be quite hard to ride, and look stupid to boot...) Gyroscopic force also has an effect here, but it is not the main player.
I found a cool site that explains it all: Motorcycle stability and steering.
main(c,r){for(r=32;r;) printf(++c>31?c=!r--,"\n":c<r?" ":~c&r?" `":" #");}
This article on counter-steering is easier to follow, I think. The picture helps. ;)