Humanoids are the hardest. Atlas is the state of the art, and you might think that because Atlas has solved backflips, building a full-sized biped robot that can just walk around should be easy by now. But it’s very much not easy, especially in the home.

For starters, there’s the noise. Many of the best and strongest humanoids use hydraulics for strength. Even electronic servo-based robots can be loud. But more importantly, bipeds are expensive, fragile, and fall over a lot. Why would you want that in your home?

The people at Ubtech, a China-based robotics company that sells a wide range of home and toy robots, are working on the impossible, and possibly the impractical: Walker, a human-sized biped for the home.

Walker is supposed to be a “complete home butler,” which mostly means it can patrol your home, act as a calendar and email assistant, and play a slow game of soccer with your kids. It has a smooth, quiet gait, which Ubtech credits to its homegrown digital servos. I watched Walker do a little dance, chase a soccer ball, and descend stairs. (The stair ascend demo wasn’t ready yet.)

Of course, most biped robots fall over a lot, and are too heavy to have anywhere near your kids. Walker is a surprisingly light 82 pounds, and is designed to be in balance at all times. If it loses power, it should stay stable right where it is. It’s also designed to fall away from danger if it has to fall.

I’m not positive a robot without a manipulation arm can really be called a “home butler,” so thankfully Ubtech is working on arms to add on to Walker. Ubtech also builds a wheeled robot with a robot arm, so the real challenge won’t be building an arm, but keeping Walker in balance while it’s manipulating its environment.

Walker is an ambitious project, most of all because it’s designed to be relatively affordable — in full-sized biped terms, that means “less than hundreds of thousands of dollars,” but I got the impression Ubtech is aiming for a lot lower than that. Walker is supposed to launch sometime in 2019.