Robert Playter

We built a few different versions of them.

But the first one, the very earliest ones, you know, didn't work very well.

We would take them out and

It was hard to get a go-kart engine driving a hydraulic pump.

Oh, is that what it was?

And having that all work while trying to get the robot to stabilize itself.

Oh, it absolutely was, right?

We weren't trying to design the best robot hardware at the time.

And we wanted to buy an off-the-shelf engine.

And so many of the early versions of Big Dog had literally go-kart engines or something like that.

Are those gas-powered?

Yeah, gas-powered two-stroke engines.

And the reason why it was two-stroke is two-stroke engines are lighter weight.

And we generally didn't put mufflers on them because we're trying to save the weight.

And we didn't care about the noise.

And so these things were horribly loud.

But we're trying to manage weight because managing weight in a legged robot is always important because it has to carry everything.

That said, that thing was big.

Yeah, I mean, the early versions, you know, stood about, I don't know, belly high, chest high.

You know, they probably weighed maybe a couple of hundred pounds.