Can shark skin help us save energy in industry? This is the question driving STELLAR (Surface Texturing with Laser for Large Areas with Riblets), a European project that combines science, technology and nature to develop textured surfaces capable of reducing friction in industrial applications. 

With the participation of Izertis and international partners, this initiative aims to improve energy efficiency in key sectors such as propulsion, transport and energy.

In nature, the skin of some shark species is made up of tiny scales that generate microchannels called riblets. These structures, arranged parallel to the water flow, reduce turbulence and allow the animal to move with less resistance, optimising its energy. 

STELLAR seeks to transfer this principle to the industrial field, with applications in propulsion, fluid transport and power generation systems, such as wind turbine blades.

The challenge: reproducing nature on an industrial scale

Although riblets appear simple, their manufacture is highly complex. These are micrometric structures, where minute variations can significantly alter performance. The project addresses challenges such as:

• Design and predict the behaviour of riblets before manufacturing them.
• Produce them with laser precision and mass replication.
• Ensure repeatability and assess final quality. 

To achieve this, STELLAR integrates biomimetrics, advanced laser technology and analysis of data using artificial intelligence, avoiding traditional trial-and-error processes and relying on predictive and automated methodologies.

A multidisciplinary and transnational approach

STELLAR brings together organisations from Austria, Germany, France and Spain, each with their own specialisation:

• Bionic Surface Technologies (Austria): fluid dynamic simulation to optimise the design of riblets and their experimental validation in wind tunnels and hydrodynamic channels.
• University of Applied Sciences Mittweida (Alemania): leading the development of manufacturing processes, from direct laser engraving to mass replication using metal moulds.
• Amplitude (France): focuses on perfecting femtosecond laser systems to scale up production.
• Izertis: plays a key role in advanced data analytics with artificial intelligence and machine learning for:
  • Predictive Analysis: Development of machine learning models for predicting the performance of different configurations of riblets prior to their physical manufacture.
  • Quality Control: Implementation of automatic analysis systems for comparison between manufactured structures and design specifications.
  • Process Optimisation: Application of optimisation algorithms for continuous improvement of manufacturing and design parameters.

Impact and prospects

STELLAR aims not only to translate a functional model from the biological domain into industrial solutions, but also to demonstrate how international collaboration and integration of disciplines are key to tackling technological challenges.

It is also an example of transnational collaboration in the development of new technologies, which are increasingly demanding multilateral approaches to solving fundamental problems. 

The project started in September 2023, has a duration of 36 months and aims to achieve a TRL (Technology Readiness Level) 7, meaning the validation of prototypes in real environments.

European support

STELLAR has a total budget of EUR 1,260,452 and public funding of EUR 905,570, financed through the M-ERA.NET 2022 call for proposals by the regional innovation agencies of Saxony (Germany), Austria, Nouvelle-Aquitaine (France) and Asturias (Spain).