Humanoid robot achieves controlled flight using jet engines and AI-powered systems

The Italian Institute of Technology (IIT) has reached a milestone in humanoid robotics by demonstrating the first flight of iRonCub3, the world’s first jet-powered flying humanoid robot specifically designed to operate in real-world environments.

The research team studied the complex aerodynamics of the artificial body and developed an advanced control model for systems composed of several interconnected parts. The overall work on iRonCub3, including real flight tests, took about two years. In the latest experiments, the robot was able to lift off the floor by approximately 50 cm while maintaining its stability. The achievement paves the way for a new generation of flying robots capable of operating in complex environments while maintaining a human-like structure.

The aerodynamics and control studies have been described in a paper published in Communications Engineering.

The research was carried out by roboticists of IIT in Genoa, Italy, in collaboration with the group of Alex Zanotti at DAER Aerodynamics Laboratory of Polytechnic of Milan—where a comprehensive series of wind tunnel tests were performed—and the group of Gianluca Iaccarino at Stanford University—where deep learning algorithms were used to identify aerodynamic models.

The robot flight demonstration represents the latest milestone of the Artificial and Mechanical Intelligence (AMI) Lab at IIT in Genoa, led by Daniele Pucci. Their research aims to push the boundaries of multi-modal humanoid robotics, combining terrestrial locomotion and aerial mobility to develop robots capable of operating in unstructured and extreme environments.

iRonCub3 is the technological evolution of previous prototypes and is based on the latest generation of the iCub humanoid robot (iCub3), developed to be teleoperated. It integrates four jet engines, two mounted on the arms and two on a jetpack attached to the robot’s back.

Modifications to the iCub hardware design were required to support the external engines, such as developing a new titanium spine and adding heat-resistant covers for protection. The robot combined with the jet engines weighs about 70 kg, while the turbines can provide a maximum thrust force of more than 1000 N. This configuration enables the robot to hover and perform controlled flight maneuvers even in the presence of wind disturbances or environmental uncertainties. The exhaust temperature can reach 800 degrees.

“This research is radically different from traditional humanoid robotics and forced us to make a substantial leap forward with respect to the state of the art,” explains Daniele Pucci. “Here, thermodynamics plays a pivotal role—the emission gases from the turbines reach 700°C temperature and flow at nearly the speed of sound. Aerodynamics must be evaluated in real-time, while control systems must handle both slow joint actuators and fast jet turbines. Testing these robots is as fascinating as it is dangerous, and there is no room for improvisation.”

The AMI research team focused on the platform’s dynamic balance, which is made particularly complex by the robot’s humanoid morphology. Unlike conventional drones, which have symmetric and compact structures, iRonCub3 has an elongated shape, with masses distributed across movable limbs and a variable center of mass. This required the development of advanced flight balance models that consider the robot’s multibody dynamics and the interaction between jet propulsion and limb movements.

Moreover, the movable limbs significantly complicate the aerodynamics, which change with every motion of any of the robot’s limbs.

The researchers have performed extensive wind tunnel experiments, advanced Computational Fluid Dynamics (CFD) simulations and developed AI-based models capable of estimating aerodynamic forces in real time.

“Our models include neural networks trained on simulated and experimental data and are integrated into the robot’s control architecture to guarantee stable flight,” explains Antonello Paolino, first author of the paper and Ph.D. student in a joint program between the IIT and Naples University, who spent a semester as a visiting researcher at Stanford University.

As a result, iRonCub3 is equipped with AI-powered control systems that allow it to fly while handling high-speed turbulent airflows, extreme temperatures, and the complex dynamics of multi-body systems.

The advanced aerodynamic modeling developed by IIT demonstrates that it is possible to maintain posture and stability even during non-stationary maneuvers, such as sequential engine ignition or changes in body geometry.

These studies can be transferred to other robots with unconventional morphologies, representing a unique case compared to classical drones, whose balance relies on symmetry and simplified control strategies that often neglect the robot’s own aerodynamics and thermodynamics.

The final design of iRonCub3 is the result of an advanced co-design process, specifically developed to integrate artificial intelligence and multi-physics into the design of flying robots. These techniques, which are innovative in the field of robotics, allow for the simultaneous optimization of both body shape and control strategies, considering the complex interactions between aerodynamics, thermodynamics, and multibody dynamics.

Co-design was used to determine the optimal placement of the jet turbines to maximize control and stability during flight. Advanced design techniques were also employed to manage the heat dissipation generated by the engines, thus ensuring the structural integrity of the robot even under extreme operating conditions.

The robot has been completely re-engineered to withstand the harsh conditions associated with aerial locomotion, introducing major improvements focused on precision actuation, enhanced thrust control via integrated sensors, and advanced planners for coordinated takeoff and landing.

Throughout the design process, numerous iterative adjustments were made based on the results of advanced simulations and experimental testing, leading to the robot’s current configuration. This approach has allowed the team to overcome the limitations of traditional methodologies and represents a step forward in the automatic and integrated design of complex robotic systems.

The first flight tests of iRonCub3 were conducted in IIT’s small flight-testing area, where the robot was able to lift off the floor by approximately 50 cm. In the coming months, prototype testing will continue and will be further enhanced thanks to a collaboration with Genoa Airport (Aeroporto di Genova), which will provide a dedicated area that will be set up and equipped by the Italian Institute of Technology in compliance with all required safety regulations. The area will host future experimental campaigns.

Applications of flying humanoid robots like iRonCub3 are envisioned in a variety of future scenarios, such as search-and-rescue operations in disaster-struck areas, inspection of hazardous or inaccessible environments, and exploration missions where both manipulation capabilities and aerial mobility are essential.