In one of the most technologically advanced undertakings of recent times, a team of robots diligently explored a simulated Martian landscape on Earth this summer, more precisely in Germany, while all commands came from an altitude of over 400 kilometers – from the International Space Station (ISS). The astronaut operating this robotic unit was not physically present on the ground but was floating in microgravity, transforming into an avatar for the robotic explorers on the ground. This event marked the culmination, the fourth and final session of an extremely important experiment known as Surface Avatar. This is a fruitful collaboration between the European Space Agency (ESA) and the German Aerospace Center (DLR), whose primary goal was the development and refinement of methods by which astronauts will in the future manage entire teams of robots in performing complex tasks on the surface of the Moon and Mars.

Astronaut as an Avatar: Human Intuition Above the Earth

At the center of this complex operation was NASA astronaut Jonny Kim. Stationed in the Columbus module on the ISS, Kim spent approximately two and a half hours controlling the robotic crew on Earth. His role went beyond mere remote control; he was the brain of the operation, the key decision-maker and strategist who directed the actions of the mechanical explorers. Using an advanced interface, Kim could delegate tasks, monitor mission progress, and intervene when necessary, demonstrating how human intuition remains irreplaceable even in an era of high automation. The entire experiment was designed so that the astronaut had minimal prior preparation on the details of the tasks, thereby raising the mission's realism to a higher level and testing the ability of the system and the human to improvise in unforeseen situations.

The Robotic Team on 'Mars'

On Earth, in the controlled environment of DLR's center in Oberpfaffenhofen, which faithfully simulates the inhospitable terrain of Mars, was a diverse team of four robots, each with its own specialized abilities. The main stars were the humanoid robot Rollin' Justin and the quadrupedal robot Spot. Rollin' Justin, the pride of DLR's engineering, is a wheeled humanoid with two extremely dexterous arms and four-fingered hands, capable of manipulating objects with great precision. Its lightweight carbon fiber arms can lift a load of up to 14 kilograms per arm, and it has as many as 51 degrees of freedom of movement, allowing it to retrieve objects from the ground and from a height of up to two meters. In the mission, Justin was responsible for delicate tasks such as transferring collected samples to the lander.

His partner, ESA's robot Spot, is a quadrupedal platform known for its extraordinary mobility and ability to autonomously navigate very demanding and uneven terrains. While Justin required a mix of direct control and pre-programmed commands, Spot was tasked with independently navigating the simulated Martian soil, finding sample containers, and marking their locations. This division of labor is a key element of the "scalable autonomy" concept, where the astronaut-operator takes on the role of a supervisor, delegating routine tasks to autonomous systems so they can focus on strategic decisions and problem-solving.

Complex Mission Scenarios: Testing the Limits of Autonomy

The final session of the Surface Avatar experiment brought new, most complex scenarios to date. In the first task, Jonny Kim coordinated Justin and Spot in a mission to collect scattered sample containers. Spot, using its advanced navigation algorithms, independently explored the terrain and located the targets. Afterward, Kim would take control of Justin, guiding him to the marked locations so the robot could pick up the containers with its dexterous hands and carefully transport them to the simulated lander. This synergy tested the fluidity of switching between autonomous operation and teleoperation, which is crucial for the efficiency of future planetary missions.

The second scenario was even more challenging and designed to test the ability of the system and the astronaut to respond to unforeseen failures. In this task, ESA's Interact rover, a vehicle designed for transport, carried DLR's robot Bert to the entrance of a simulated Martian cave. Bert is a smaller, agile quadrupedal robot resembling a dog, specialized for moving in narrow and inaccessible spaces where larger, wheeled robots cannot go. After Kim used one of the robots to remove a rock blocking the entrance, he sent Bert in to explore. However, the experiment included a planned failure – one of Bert's legs was simulated to have failed. At that moment, Kim had to access Bert's system in real-time and reprogram its walking algorithm, teaching it a new, three-legged way of moving. After a successful "rehabilitation," Bert continued its mission inside the cave, where it successfully detected simulated signs of ice presence, demonstrating the extraordinary adaptability of the entire human-machine system.

Technology That Erases Boundaries: The Interface of the Future

All this interaction is made possible by a sophisticated control interface jointly developed by ESA and DLR. The workstation on the ISS consists of a laptop with a graphical mission display and two specialized controllers. One is a joystick with seven degrees of freedom of movement that allows for intuitive control of the robot's movement and viewing direction. The other, even more advanced, is a haptic device. This technology allows the astronaut to literally "feel" what the robot feels. When Justin's hand grasped an object, Kim would feel the resistance, weight, and texture of that object on his controller. This transmission of the sense of touch is crucial for performing delicate operations that require sub-millimeter precision. The interface also allows Kim to switch between a first-person view, for full immersion in teleoperation, and a bird's-eye view mission map, for better strategic oversight of the entire robot team. Although the signal between the ISS and Earth travels nearly 90,000 kilometers via satellites, causing a delay of about 800 milliseconds, the system is designed to compensate for this lag and enable fluid and efficient control.

A Step Closer to the Moon and Mars

Through four successful sessions, the Surface Avatar project team has perfected the approach to human-robot interaction, improving both direct teleoperation and methods of delegating tasks to autonomous systems. The experiments have provided invaluable data on which tasks astronauts prefer to perform under direct control and which are safe and efficient to leave for the robots to perform independently. Project leaders emphasize that these experiments have fulfilled all the technical prerequisites for managing complex robotic missions on Mars and for establishing future permanent research stations on the Moon. With this project, Europe has built unique expertise in the field of space robotics, and the developed technologies also have potential applications on Earth, in industries such as nuclear or offshore energy. The successful conclusion of the Surface Avatar saga, symbolically crowned by a remote handshake between astronaut Kim and the project leader on the ground via Justin's robotic arm, is not just a technological achievement, but a clear indicator that the collaborative future of humans and robots in space exploration has already begun.