“CLeo” Develops Automated Inspection Technology for Next- Generation Membrane Modules

Smart Leak Detection: Laser-based Testing System Ensures Reliable Filter Quality

Press Release (No. 04) – Fraunhofer IWS Dresden /

A new testing system shall detect leaks in filter modules automatically, non-destructively, and in real time. DBI Gas- und Umwelttechnik spearheads the CLeo project, where the system is currently under development. The Fraunhofer Application Center for Optical Metrology and Surface Technologies AZOM contributes a laser-based leak detection method and an AI-driven analysis process. The system aims to fundamentally improve the currently manual quality control in membrane production. It will help reduce production costs, meet environmental standards, and ensure the long-term quality of industrial filtration systems – efficiently, precisely, and sustainably.

An employee of project partner WTA Unisol performing manual quality control on filtration membranes. The inspection method developed in the CLeo project aims to accelerate workflows and improve inspection reliability.
© WTA Unisol GmbH
An employee of project partner WTA Unisol performing manual quality control on filtration membranes. The inspection method developed in the CLeo project aims to accelerate workflows and improve inspection reliability.
The laser-based technology combines optical spectroscopy with AI-supported analysis, enabling automated and reliable quality control in membrane production.
© Fraunhofer IWS, AI-enhanced image
The laser-based technology combines optical spectroscopy with AI-supported analysis, enabling automated and reliable quality control in membrane production.

The demand for high-performance filtration systems continues to rise. New EU directives, such as the upcoming wastewater regulation mandating a fourth purification stage, drive this trend. However, current quality control methods rely on manual testing. These procedures remain labor-intensive, time-consuming, and unsustainable. Conventional tests like bubble testing in water baths lack scalability, automation, and reliability. The BMBF-funded joint project “Cyber-Physical System for Inline Leak Detection in Membrane Filtration Modules Using Spatially Resolved Diode Spectroscopy” (CLeo) addresses this challenge. The goal: a cyber-physical inline inspection system that detects and analyzes leaks during production without damaging the sensitive membranes.

“Our goal with CLeo is to enable high-precision leak detection fully integrated into industrial production,” explains Dr. Tobias Baselt, Head of Optical Fiber Technologies at Fraunhofer AZOM. “Combining laser spectroscopy, intelligent data processing, and automated mechanics results in a robust solution that ensures quality while saving time, resources, and costs.”

Digital Innovation Meets Industrial Practice – for the Environment, Industry, and Society

The technology uses spatially resolved diode spectroscopy. A test gas flows through the filter module; leaks are visualized via specific absorption signals. The system evaluates data in real time and precisely locates each defect. Operators can then repair modules or remove faulty units from the line. Beyond economic efficiency, the system supports resource conservation: Inspection and repair times drop significantly, and the modules’ post-treatment becomes obsolete due to the water bath. Automated detection and selective rework reduce waste, advancing sustainable production. The system adapts across industries – from water management to food processing, pharmaceuticals, and chemical manufacturing – wherever leak-tight components are critical.

Interdisciplinary Consortium Driving Innovation

The two-year project launched on January 1, 2025, with total funding of €1.4 million as part of the BMBF’s “KMU-innovativ: Future of Value Creation” program. The consortium brings together expertise in materials science, mechanical engineering, metrology, and digitalization:

  • Fraunhofer AZOM: Laser-based leak detection and AI analysis
  • DBI Gas- und Umwelttechnik GmbH: Project coordination, gas flow development
  • ibl Maschinenbau GmbH: Robotic handling of membrane modules
  • WTA UNISOL GmbH: System integration, development of test modules with defined leaks
  • University of Applied Sciences Zwickau (WHZ): Design of protective textiles for optimized measurement conditions

 

Infobox

Background: Membrane Filtration in Transition

Modular micro- and ultrafiltration systems play a vital role in the safe and space-efficient treatment of industrial wastewater. However, manufacturing processes such as bonding and welding often cause leaks, leading to costly rework or scrap. Manual inspection methods still dominate quality control, but form a bottleneck in production. The CLeo project addresses this challenge: with digital precision, automated detection, and AI-based analysis, the project aims to pave the way for scalable, economical, and environmentally responsible filter manufacturing.

About Fraunhofer AZOM

The Fraunhofer Application Center for Optical Metrology and Surface Technologies AZOM is operated by Fraunhofer IWS in cooperation with the University of Applied Sciences Zwickau (WHZ). The center develops cutting-edge approaches in optical metrology, image processing, process control, and surface characterization. Its mission: to swiftly transfer scientific findings into industry-ready applications. Fraunhofer AZOM bridges applied research and industrial use, particularly in medical technology, automotive engineering, mechanical engineering, and semiconductor manufacturing.

The work of Fraunhofer AZOM spans the whole value chain, offering feasibility studies, contract measurements, integration of existing technologies, and development of new optical and surface technologies. Its services include optical inspection systems, application-specific sensor and actuator technologies, and non-destructive process and component monitoring. The center also develops electronic controls, application-specific software, and optical elements such as light sources and fiber-based assemblies, especially for technical challenges that current market solutions cannot solve.

More Information: s.fhg.de/azom


About the University of Applied Sciences Zwickau (WHZ)

WHZ focuses on engineering, business, and quality of life. Following its vision of becoming a “University for Mobility,” WHZ drives research in five strategic fields: Vehicle and Production, Energy and Infrastructure, Cyber Physical Systems and Digitalization, Health and Medical Technology, Sustainability and Interculturality.

More Information: www.fh-zwickau.de

Funding Notice

Sponsored by the Federal Ministry of Education and Research
Sponsored by the Federal Ministry of Education and Research

The project is funded by the Federal Ministry of Education and Research (BMBF) under the program "KMU-innovativ: Future of Value Creation".
Funding reference number: 02P24K143.