Silent Floating Robot Offers Gentle Indoor Companionship

Japanese researchers have developed a silent, floating companion robot designed to glide through indoor spaces. This prototype, a collaboration between a team at Keio University in Tokyo and the MIT Media Lab, moves without the noise of drones or the limitations of wheeled devices. Its soft helium body allows safe contact, enabling gentle nudges, reminders, and even hugs without risk of injury to people or pets.

Credit: Mingyang

The lighter-than-air prototype aims to be approachable, safe, and comfortable within human environments. Unlike conventional drones, which use spinning propellers for lift, these soft floating robots (SFRs) stay airborne via helium-filled envelopes. Buoyancy manages most of the robot's weight, meaning its propulsion system only provides movement and steering. This design results in lower energy consumption, longer hovering times, and virtually silent operation, devoid of the rotor noise and strong downwash associated with multirotor drones.

Inspired by fictional characters such as Tinker Bell, Pokémon's Mew, and Studio Ghibli's Soot Sprites, the prototype resembles a small floating white whale. This creature-like machine glides through the air using soft flapping fins rather than exposed propellers, exhibiting smooth, rhythmic movements. It performs tasks like waking users, delivering reminders, providing companionship during study, dancing with its owner, and offering playful entertainment. According to the research team, the robot is designed to act as a friendly physical presence that naturally shares indoor space with people, rather than replacing smartphones or smart speakers. And the researchers have established a systematic interaction design framework for such devices, incorporating input from 12 experts in robotics, human computer interaction, and design.

One primary advantage of this robot is its soft, helium-filled structure. This lightweight, compliant body makes accidental contact with people, pets, and furniture considerably safer than encounters with conventional drones. Instead of relying solely on collision avoidance systems, the robots utilise "safety through compliance," which allows for gentle physical interactions. These include soft nudges, tactile reminders, and even light embraces, creating a more integrated and less intrusive presence within shared spaces.

The buoyant design also enables the robots to use previously unoccupied three dimensional indoor space. They can float above furniture, navigate staircases, and position themselves at eye level, overhead, or near the floor. This accessibility reaches areas inaccessible to wheeled robots, while remaining far less intrusive than traditional drones. But the prototype combines a helium envelope with carbon fiber reinforced flapping wings, lightweight micro servos, a microcontroller, and a compact lithium battery. Symmetrical wing flapping generates forward thrust, and differential wing motion provides steering for smooth, quiet indoor flight.

Payload capacity remains a significant engineering challenge for these devices. Helium provides approximately one gram of lift per litre, necessitating careful design considerations. To maximise performance, the researchers advise using ultra light drone grade electronics, offloading heavy computation to external systems, and minimising onboard processing. The developed framework supports various propulsion methods, including flapping wings, oscillating fish like tails, jellyfish inspired actuators, vectored thrust, and propeller free ultrasonic micro blowers.

These researchers believe that the design could facilitate more natural and emotionally engaging human robot interaction in domestic settings. They envision these floating robots serving as emotional companions, ambient assistants, and household helpers. This development aims to open a new frontier for everyday human robot interaction, establishing a friendly physical presence that naturally shares indoor space with people, rather than replacing existing smart devices.

• Japanese researchers developed a silent, floating companion robot using helium buoyancy and soft inflatable bodies.

• The prototype moves like a living creature, performing tasks such as waking users, delivering reminders, and offering companionship.

• Its soft, compliant body allows for safe, gentle physical interactions, contrasting with collision avoidance systems.

• The robot occupies three dimensional indoor space, navigating stairs and positioning itself at various heights.

• Payload capacity remains an engineering challenge, with recommendations for ultra light electronics and offloading computation.

Source: INTERESTING ENGINEERING