This little fellow was developed

by a group of 10 undergraduate students

at the Autonomous Systems Laboratory

at ETH-Zurich.

Our robot belongs to a family of robots

called Ballbots.

Instead of wheels, a Ballbot is balancing

and moving on one single ball.

The main characteristics of such a system is

that there's one sole contact point to the ground.

This means that the robot

is inherently unstable.

It's like when I am trying to stand

on one foot.

You might ask yourself, what's the usefulness

of a robot that's unstable?

Now we'll explain that in a second.

Let me first explain how Rezero

actually keeps his balance.

Rezero keeps his balance by constantly

measuring his pitch angle with a sensor.

He then counteracts and avoids toppling over

by turning the motors appropriately.

This happens 160 times per second,

and if anything fails in this process,

Rezero would immediately fall to the ground.

Now to move and to balance,

Rezero needs to turn the ball.

The ball is driven by three special wheels

that allow Rezero to move into any direction

and also move around his own axis

at the same time.

Due to his instability, Rezero is always

in motion. Now here's the trick.

It's indeed exactly this instability that allows

a robot to move very [dynamically].

Let's play a little.

You may have wondered what happens

if I give the robot a little push.

In this mode, he's trying to maintain

his position.

For the next demo, I'd like you to introduce

to my colleagues Michael, on the computer,

and Thomas who's helping me onstage.

In the next mode, Rezero is passive,

and we can move him around.

With almost no force I can control

his position and his velocity.

I can also make him spin.

In the next mode, we can get Rezero

to follow a person.

He's now keeping a constant distance to Thomas.

This works with a laser sensor

that's mounted on top of Rezero.

With the same method, we can also

get him to circle a person.

We call this the orbiting mode.

All right, thank you, Thomas.

(Applause)

Now, what's the use of this technology?

For now, it's an experiment, but let me

show you some possible future applications.

Rezero could be used in exhibitions or parks.

With a screen it could inform people or show

them around in a fun and entertaining way.

In a hospital, this device could be used to

carry around medical equipment.

Due to the Ballbot system, it has a very small

footprint and it's also easy to move around.

And of course, who wouldn't like

to take a ride on one of these.

And these are more practical applications.

But there's also a certain beauty

within this technology.

(Music)

(Applause)

Thank you.

(Applause)

Thank you.