Picture this: you're expecting a package delivery and hear a knock on the door.

Though, instead of a human with two legs, it's a robot dog with four — that pranced down the street and up the steps autonomously on 3D-printed limbs.

It's a future Boston Dynamics CEO Marc Raibert envisions for one of his company's latest robots, SpotMini, a prototype often called "creepy" that he showed off on stage at the TED Conference in Vancouver this week.

The robot was partly driven by a human — but partly moved on its own, displaying two skills that are pretty cutting edge for a robot: picking up a fragile object without crushing it and using stereo cameras to decide where to step on unfamiliar terrain.

"I think it won't be too long until we have robots like this in our homes," he told the crowd in the session called "Our Robot Overlords." Should we be scared? he was asked.

"I'm not scared at all, I think that's up to each of you." 

Delivery dogs aside, the tech world is very divided on this larger question: as artificial intelligence advances, how worried should we be?