Researchers at the Italian Institute of Technology (IIT) have completed the first successful flight of iRonCub3, marking a major breakthrough in humanoid robotics. The robot lifted off the ground by approximately 50 centimeters and maintained stability throughout the maneuver, demonstrating controlled flight with a human-like form.

iRonCub3 is the world’s first jet-powered flying humanoid robot designed for real-world environments. The development process, including live flight testing, took around two years. Engineers at IIT developed advanced control systems to manage the robot’s interconnected parts and analyzed its complex aerodynamics to enable stable flight.

This achievement has been detailed in a new publication in Nature Communications Engineering, produced in collaboration with experts at the Polytechnic of Milan’s DAER Aerodynamics Laboratory and Stanford University. The teams performed extensive wind tunnel tests and developed AI-powered models to simulate and control the robot’s aerodynamic behavior.

Led by Daniele Pucci at the Artificial and Mechanical Intelligence (AMI) Lab, the project aims to expand the capabilities of humanoid robots by combining walking and flying functionalities. This multimodal approach is essential for navigating unstructured or extreme environments.

iRonCub3 is built on the latest iCub humanoid robot platform, iCub3, which was originally designed for remote operation. To enable flight, engineers equipped the robot with four jet engines—two on the arms and two on a jetpack mounted on the back. The structure was reinforced with a titanium spine and heat-resistant covers to withstand engine exhaust temperatures that can reach up to 800°C.

With the engines installed, the robot weighs approximately 70 kilograms and can generate over 1000 newtons of thrust. This allows for controlled hovering and stable flight even in the presence of wind or unpredictable environmental conditions.

The project represents a departure from conventional humanoid robotics. Unlike drones, which typically feature compact, symmetrical bodies, iRonCub3 has an elongated form with movable limbs and a shifting center of mass. This makes balancing in flight more complex and required the development of new multibody dynamics models.

Thermodynamics plays a central role due to the high temperatures and gas velocities involved. Real-time aerodynamic evaluation and coordination between slow-moving joint actuators and fast-reacting jet turbines were critical to achieving controlled flight.

Daniele Pucci noted that testing the robot is both fascinating and dangerous, requiring precision and careful planning. There is no room for improvisation when dealing with high-speed jet propulsion and humanoid instability.

The team developed neural networks trained on simulated and experimental data to estimate aerodynamic forces in real time. These models are integrated into the control systems and are key to maintaining stable flight during dynamic maneuvers, such as engine ignition sequences or shifts in limb configuration.

Antonello Paolino, the paper’s first author and a PhD student at IIT and Naples University, conducted part of his research at Stanford University to help develop these AI models.

The robot’s final design was achieved through an advanced co-design process, which optimized both the mechanical structure and control algorithms. This approach considered the interactions between aerodynamics, thermodynamics, and multibody dynamics from the outset.

Jet engine placement was carefully determined to maximize balance and control. Heat management systems were developed to protect structural components under extreme conditions. Precision actuation, advanced thrust sensors, and coordinated flight planners were all integrated into the robot to ensure safe and effective aerial performance.

Iterative simulations and experimental tests guided the refinement of the robot’s design, moving beyond the limitations of traditional robotic development methodologies.

Initial tests were conducted in IIT’s flight-testing area, where the robot demonstrated the ability to lift off and hover in place. In the next phase, testing will continue at Genoa Airport, where a dedicated area will be established in collaboration with airport authorities and outfitted for safe experimentation.

iRonCub3 opens the door to a range of potential future applications, including search-and-rescue missions in disaster zones, inspection of hazardous or hard-to-reach environments, and exploratory missions where both flying and manipulation are essential.

This milestone represents a new era in robotics—one where human-like machines are not only able to walk and interact, but also to take to the skies.

By Impact Lab