Drones have long since evolved in Europe from a niche product for hobbyists to indispensable tools in business, security and research. Whether inspecting critical infrastructure, monitoring industrial facilities, assisting in rescue operations or in urban mobility projects – unmanned aerial vehicles are versatile. At the same time, the demands on their reliability, robustness and safety architecture are increasing. Especially in densely built-up cities, industrial facilities or disaster areas, any collision can cause critical damage – both to the drone and to the surrounding area.

Swiss researchers at the Swiss Federal Institute of Technology Lausanne (EPFL) have now developed an aircraft that elegantly addresses this problem: the ‘SWIFT’ drone. Inspired by the woodpecker, whose brain is mechanically decoupled from its beak, the SWIFT drone can survive collisions almost unscathed – a principle that has hardly been applied in drone development to date.

Biological model: the woodpecker as an engineer

The woodpecker pecks at tree bark at high speed without damaging its brain. The secret lies in mechanical decoupling: the hard beak, the flexible hyoid bone and a sponge-like bone between the hyoid bone and the skull act as a shock absorber. The brain has additional space to absorb movements and is thus protected from injury.

EPFL engineers applied this principle to the SWIFT drone. Rigid carbon fibre rods replace the beak, curved strips of the same material take on the function of the hyoid bone, and elastic cables represent the shock-absorbing spongy bone. The main skull is replicated by carbon fibre plates attached to carbon fibre tubes with polylactic acid plastic clips.

Mechanics that absorb collisions

The heart of the drone – electronics, motor and propeller – hangs in a flexible ‘skull’ that yields up to 22 centimetres in the event of an impact. The energy of an impact is distributed, protecting the critical components. Measuring 980 millimetres long, 1,500 millimetres wide and weighing 710 grams, the SWIFT drone is robust enough to remain intact in collisions, yet agile and stable enough to fly in a controlled manner.

The developers focused on variable stiffness: the structure is rigid enough to enable precise flight manoeuvres and flexible enough to cushion impacts in confined and complex environments. Indoor tests at speeds of almost 30 kilometres per hour demonstrated its resistance to obstacles, followed by outdoor flights that proved the drone’s adaptability in real-world conditions.

Fields of application in Europe

Thanks to its collision resistance, SWIFT is particularly suitable for the following areas of application:

• Urban environment: city surveillance, bridge inspection, traffic monitoring or logistical support in areas with poor visibility.
• Forest and nature conservation: reconnaissance flights in densely forested areas, wildlife monitoring or inspections in regions that are difficult to access.
• Disaster management: Rescue operations in earthquake zones, floods or industrial accidents where obstacles and debris can endanger the flight path.
• Research and industrial inspection: Safe inspection of high-voltage power lines, wind turbines or other critical infrastructure without the risk of a crash compromising the operation.

The ability to mechanically cushion collisions significantly increases operational safety and reduces downtime due to repairs. This is particularly important in European metropolitan areas, where drones are increasingly operating in densely populated environments and a crash could endanger not only the hardware but also people.

Perspectives and outlook

The SWIFT drone shows how biomimetic principles can change drone development. While classic drones rely on sensors, AI and emergency protocols when encountering obstacles, SWIFT complements these approaches with mechanical robustness. In Europe, such drones could set standards for urban drone management, safety flights in complex environments and disaster response operations in the future.

The video about SWIFT impressively demonstrates its collision resistance: https://youtu.be/kyvZJ6cJJGg

EPFL’s research highlights an important trend: the integration of biological principles into technology to make drones not only smarter but also more robust. In view of increasing regulatory requirements in Europe – for example, regarding drone flights in cities and over crowds – this could be crucial for integrating drones efficiently, safely and reliably into European airspace.