Helios is a new four-armed robot from Zurich-based Orbit Robotics, and at first glance, it reminded me of Goro from Mortal Kombat. But unlike the prince from Outworld, Helios is not built for combat. It is designed to help astronauts on space stations with the repetitive, time-consuming work that keeps life in space running.
Orbit Robotics says that in microgravity, legs are not much help. Instead of walking or standing, Helios needs to move through tight station interiors, hold itself steady, and handle cargo, tools, or equipment. Its four-arm design turns extra limbs into both mobility aids and working hands.
Why four arms make sense in orbit
The design looks strange because most humanoid robots, like the Unitree G1 and Tesla Optimus, are still shaped around Earth-based movement. Helios takes a more practical approach for space.
Its arms do not use bulky motors at every joint. Instead, they are tendon-driven, with motors placed closer to the shoulders, and force is transferred through cables and spools. This should help keep the arms lighter while still giving them the range of motion needed for station work.
Helios also uses a rolling-contact elbow joint, which gives it smoother and more controlled movement. Sudden or uneven motion in space can destabilize the robot, so this mundane-looking feature is actually quite important. The four-arm setup also allows the robot to stabilize its position with two arms and use the other pair to handle cargo, tools, or equipment.
Built to save astronaut hours
Unloading cargo, sorting supplies, tracking inventory, moving equipment, and basic maintenance take up a large chunk of astronauts’ time in space. Maintenance alone is said to account for around 35% of crew time, while one cargo unloading cycle can take nearly 50 hours.
At roughly $140,000 per astronaut hour, routine work in space is expensive. A robot like Helios could help reduce how much of that time is spent on logistics and maintenance.