Robert Playter

And so that is one of the hard problems of legged locomotion.

And you have to do that for natural movement.

It's not necessarily required for natural movement.

It's just required...

We don't have a gravity force that you can hook yourself onto to apply an external force in the direction you want at all times.

The only external forces are being mediated through your feet.

And how they get mediated depend on how you place your feet.

And you can't just...

You know, God's hand can't reach down and push in any direction you want.

You know, so.

There is.

The humanoid form is attractive in many ways, but it's also a challenge in many ways.

You have this big upper body that has a lot of mass and inertia.

And throwing that inertia around increases the complexity of maintaining balance.

And as soon as you pick up something heavy in your arms, you've made that problem even harder.

And so in the early work in the leg lab and in the early days at the company, we were pursuing these quadruped robots, which had a kind of built-in simplification.

You had this big rigid body and then really light legs.

So when you swing the legs, the leg motion didn't impact the body motion very much.

All the mass and inertia was in the body.

But when you have the humanoid, that doesn't work.