He is balancing.

O well whats the point of that?

1) To show off our nice engineering (though it doesn't balance, it's still pretty cool)
2) You notice he goes back and forth. It is surprisingly hard to keep the thing balanced while going in one direction for any significant period of time.

Summation: Dean Kamen is a genius. You don't realize how brilliant the Segway is until you try to do it yourself without computer help.

O, I totaly agree. I dont expect a FIRST team to be able to develope a segway, it would be so increadably hard! I just got really really exited!

Although I have not personally tried to balance on that device without a computer, just from looking at the segway I am not particularly impressed. Considering the center of gravity is below the center of the wheels it will naturally balance even without motors. Granted it would be foolish engineering to do otherwise, since it would be more likly to tip over; but I'm still a little disappointed.

Did your mother drop you as a child (j/k). I am not sure what you are getting at, but when a rider is on the segway it will not balance on its own without the machine being active. I mean it IS possible for a rider to find his/her center of gravity and shift it as they moved, but that would take soooooo much skill.

It naturally balances while you are standing still. Once you get moving, it's a whole different ball game.

Not really, if you were to put the device on an incline and stand on it while it rolls down it would be no different than while it is moving from your point of view. From your perspective constant speed will be just like standing still. Therefor all the motors need to do it maintain constant speed when you are upright, and accelerate you in whichever direction you should lean. That both prevent the device from tipping over and allows you to control its motion.

Like I said, try it, then you come back and tell me that.

Segway CG back of envelope calculations
 

I'm afraid you're wrong in this case, Max.

The average (height-weight proportional, for those of you who read personal ads ;-) ) person has a center of gravity that is roughly around sternum level standing straight. If you don't believe me, take martial arts that require falling (Judo, Aikido) or watch a ballet dancer in action.

Now, the segway is about 80 lbs, and typical non-Ally McBeal person is at least 120 lbs. So, even if the Segway's own CG is below the pivot axis of the wheel - the combined CG of the rider *AND* machine cannot be. Unless the Segway is MUCH MUCH heavier than the rider, which is not the case.

Your mentor's humble 2 cents anyway ;-)

Ah, but what you failed to take into account is the instinct not to fall over. A person will instintivly keep their center of gravity over their feet, therefor, for all our purposes, putting it at their feet. If the feet are below the axis of the wheels, they will reenforce the low center of gravity of the segway (even tho with that hand rail the segways own CG is probably above the axis of the wheels).

Except we do that by taking a step if we feel off balance. Not possible when standing on a Segway style platform.

So you mean to say that if you stand on a 1 foot by 1 foot platform that is tilted under you you can't keep your balance? CG occupies a point rather than a space, so you can shift your weight from foot to foot or toe to heel. If a person were not able to maintain their center of gravity over their feet they would not be able to climb a hill on account of their body remaining perpendicular to the slope and eventually tipping over.

Actually, no, you can't. Like I said, try it.

If you take that platform and put 2 wheels on it, I bet you'd have a very difficult time balancing on it.