There’s nothing I like more on bright and cold autumnal days than heading down to the park and watching the robot dogs playing in piles of leaves. To hear the scuttle of their little metal legs! To imagine the joy in their tiny silicon brains! Ah, what bliss.

If you’ve not experienced these delights before, then the video above from MIT’s biomimetics lab will give you the basic idea. The bots you can see are the university’s Mini Cheetah: a lightweight and modular quadruped that’s been under development for years. We saw the Mini Cheetah earlier in 2019 when it learned to backflip, but the biomimetics lab has obviously cranked up production and now has at least nine of these little bots.

Each one weighs about 20 pounds (or nine kilograms), is powered by 12 electrical motors, and can reach speeds of around six miles per hour (or 2.5 meters per second). As you can see in the video, they’re all being steered manually using what look like RC controllers.

Speaking to IEEE Spectrum earlier this year, Sangbae Kim, director of MIT’s biomimetics lab, said the bots are being used to research various problems that require a bit of ruggedness and flexibility. Their modular design lets scientists swap in new parts if they break, and their tough build can survive crashes and bangs.

“Mini Cheetah is just about the perfect size. Twenty pounds (9 kilograms) is not too small but not so big that it’s dangerous or fragile,” said Sangbae. “We designed the machine to be able to absorb the impacts, jumping and landing and so on.”

Quadrupedal robots of this sort are becoming more common as several fields of technology mature: namely battery tech, motors, cheap sensors, and machine vision. The best known example of this type of machine is Boston Dynamics’ Spot, which the company started leasing out for industrial and research work in September.

Right now these bots are mostly being used for surveying jobs, where using robots is cheaper or safer than using humans (such as on remote oil rigs). In the future, though, they’ll likely find other tasks, including package delivery and security patrols.

It’s important to note that although these robots are physically impressive, they’re not at all intelligent. Their cleverness, such as it is, lies in their mobility: their capacity to navigate rough terrain and recover from falls. But they don’t make decisions about where they walk or how they react. Spot, for example, can perform some automated functions, like a sentry mode where it patrols up and down a set path, but it’s no more able to respond to unexpected stimuli (like putting a cardboard box over its head) than a Roomba.

But remember, if you’re thinking about getting one of these happy fellas for yourself, a robot dog is for life, not just for Christmas. They’ll need daily walks, regular oil changes, and electricity bills aren’t cheap.