What if the companion robots of the future abandoned wheels, mechanical legs, and even noisy propellers to simply float around our homes like tiny living creatures? Researchers in Japan and the United States are exploring a new class of soft robots filled with helium, capable of sharing the same space with humans without the danger typically associated with flying machines.

Inspired by characters like Tinker Bell and certain Pokémon, these devices can approach a person, gently touch them, and even wrap around them in a sort of embrace. Conventional drones were never ideal for home environments; in addition to the constant noise of their motors, their propellers pose a risk to children, pets, and anyone nearby. To solve this problem, researchers at Keio University, in collaboration with the MIT Media Lab, shifted the lift to a helium-filled envelope. Since the gas keeps the robots in the air, small propulsion systems only need to control their direction.

The challenge lies in weight, because 1 L of helium can support approximately 1 g, forcing engineers to use extremely lightweight structures, microservos, compact batteries, and carbon-fiber-reinforced components. Some of the processing can also be performed externally, reducing the amount of onboard hardware, but the most interesting concept is what’s known as “safety through compliance.”

Instead of relying solely on sensors to avoid collisions, the robot’s own soft, inflatable body absorbs impacts. This allows for intentional physical interactions—it can gently tap a person on the shoulder to get their attention, accompany users around the house, or navigate stairs and obstacles that are inaccessible to wheeled robots.