Let's fasten a spoke on the inner end of each axle.

Wheels turn on axles.

When it comes to your bicycle, it is a little more complicated.

I can't tell you how wonderful this is.

The differential looks complicated, but one we understand its principle, it is amazingly simple.

Each time you step on the pedal, the wheel turns once.

When we stop one wheel, the cross bars will continue to push the spokes of the free wheel around.

And the way this happens is through the phenomenon of persistence of vision.

The wheel began to turn.

At 6 o'clock in the morning when the alarm sets off, the Clocky also starts running in the room.

The problem is no matter how small this constant is over here,

I found a tractor fan, shock absorber, PVC pipes.

We're going downhill in some rocky terrain, and the front tire of Alex gets caught in one of these crevasses here.

Let's put this bar on a pin, so that it can swing in either direction.

Well, he needs friction to start riding.

The outsides wheels must spin faster than the wheels on the inside, because they have a greater distance to travel in the same lap of time.

That's our challenge.

This is a wire drive, using bicycle wheels.

The wheel began to roll slowly.

The vehicle is actually modeled as a system with 2 non steerable wheels and 2 steerable wheels.

A unicycle has only one wheel.

The wheels turned around.

You need to turn the Tsapa.

And what you can do is just, if you give it a twirl, well they just keep going on.

The sound you just heard is the landing gear locking into place.

And good night, Watson, he added, as the wheels of the royal brougham rolled down the street.

For most small wheeled robots, they use a method called differential steering where the left and right wheel turns the opposite direction.

And then, if you saw, the panels actually rotate.

And then we touch down, we're actually on the wheels, we're ready to drive, day one.

Spin... spin... spin...

This was a video that was on European television last week showing the Spanish Minister of Industry driving this little vehicle, and when it's folded, it can spin.

The damn wheels are locked.

He's interested in playing football.

I get the same bike back, and they've taken all the little warps out of those same wheels

Gear down.

I bike to work.

I ride my bike to work.

I cycle to work.

I ride a bike to work.

Ken wants a bicycle.

Oh boy.

Now, the two Rovers, each one of them is, kind of, getting old.

It stands for Intelligent Mobility Platform with Actuated Spoke System.

So it is a vector quantity and the direction of the vector is dependant on which way it's spinning.

You don't need reverse. You don't need parallel parking.