High-altitude (drone-based) material identification for detecting potentially hazardous substances found on the ground

Towards Operational Drone-Based LIBS: System Integration, Validation and Field Performance

Authors

Andrea Somogyi¹, Attila Nagy², Miklós Veres³, Gábor Galbács⁴, Prof. Dr. Uğur Murat Leloğlu⁵

¹ Solver Unio Ltd., 34/A Angol Street, 1149 Budapest, Hungary
² Rotors & Cams Ltd., 45/B Building R Újszász Street, 1165 Budapest, Hungary
³ Institute for Solid State Physics and Optics, HUN-REN Wigner Research Centre for Physics, Konkoly-Thege Miklós Way 29–33, 1121 Budapest, Hungary
⁴ Department of Molecular and Analytical Chemistry, University of Szeged, Dóm Square 7–8, 6720 Szeged, Hungary
⁵ Department of Aerospace Engineering, Turkish Aeronautical University (THK University), Ankara, Türkiye

Corresponding author: Andrea Somogyi (somogyi. andrea@solvergroup.hu)

Abstract

Drone-mounted laser-induced breakdown spectroscopy (LIBS) represents a rapidly emerging analytical technology with strong potential for security, environmental monitoring and industrial field applications. Building upon earlier pilot developments, this study presents an extended system-level implementation and validation of a compact UAV-integrated LIBS platform. The work focuses on system integration, measurement workflow, stability considerations, and field validation using representative test samples. The results confirm that a lightweight, low-power LIBS system integrated onto a multirotor UAV can deliver reliable spectral information under realistic operational conditions, supporting the feasibility of operational deployment.

Keywords: LIBS, UAV, drone-based spectroscopy, field analysis, stand-off sensing

1. Introduction

Laser-induced breakdown spectroscopy (LIBS) has become one of the most versatile spectroscopic techniques for rapid, in situ elemental analysis. Its ability to analyze solids, liquids and aerosols without sample preparation makes it particularly suitable for mobile and remote sensing applications. In recent years, the convergence of LIBS instrumentation miniaturization and the rapid development of unmanned aerial vehicles (UAVs) has enabled the concept of drone-based LIBS systems.

While previous studies demonstrated laboratory-scale feasibility, the transition toward operational systems requires addressing practical issues such as payload integration, distance control, robustness, safety, and real-time data acquisition. This paper presents the results of a joint industrial–academic development effort aimed at moving beyond proof-of-concept and toward a practically deployable drone-based LIBS system.

2. System Architecture

2.1 UAV platform and payload integration

The LIBS system was integrated onto an industrial-grade multirotor UAV platform capable of carrying a several-kilogram payload. A vibration-isolated mounting solution and stabilized payload support were applied to ensure mechanical robustness and repeatable optical alignment under flight conditions.

2.2 LIBS measurement module

The measurement unit consists of a compact nanosecond pulsed laser (532 nm excitation), a fiber-coupled spectrometer operating in the near-UV/visible spectral range, and dedicated focusing and light collection optics. The optical layout was designed to maximize plasma emission collection efficiency while maintaining compact geometry suitable for airborne use.

2.3 Distance control and data acquisition

Precise control of the UAV-to-target distance is critical for LIBS performance. Therefore, an onboard laser distance sensor was implemented to continuously monitor the measurement distance. System control, synchronization and data acquisition were implemented in Python on a Raspberry Pi embedded computer. Each acquired spectrum is automatically time-stamped and associated with position and image data.

3. Measurement Workflow

The operational sequence follows a structured measurement protocol: the operator positions the UAV above the target, stabilizes hovering, and gradually adjusts altitude until the predefined measurement distance is reached. At this point, the laser is triggered and the emitted plasma spectrum is recorded. This approach enables reproducible measurements while ensuring operational safety.

Test measurements were performed on representative materials such as fertilizers, metal salts and mineral samples. Clear characteristic emission lines were observed, demonstrating the system’s capability to identify elemental composition under realistic conditions.

4. Challenges and Practical Solutions

Several challenges typical for drone-based LIBS were systematically addressed during development:

• Mechanical stability and vibration effects were mitigated through optimized mounting and short acquisition times.
• Distance sensitivity was managed using active laser-based ranging.
• Safety aspects related to open-field laser operation were handled via interlock logic and operational protocols.
• Data handling was optimized to allow efficient onboard storage and post-processing.

The implemented solutions significantly improved system robustness compared to early laboratory-only prototypes.

5. Validation and Performance Assessment

To validate measurement reliability, selected samples were also analyzed using a reference laboratory LIBS system. The comparison showed good qualitative agreement between airborne and laboratory spectra, confirming that the UAV-based system preserves analytical relevance despite its compact design.

Although the present system is not yet intended for fully autonomous operation, the achieved performance demonstrates that operational deployment for targeted field applications is technically realistic.

2. Figure Prototype of a UAV‑integrated LIBS measuring instrument

6. Discussion and Future Perspectives

The results indicate that compact drone-based LIBS platforms can move beyond experimental demonstrations toward applied field instruments. Potential application areas include hazardous material identification, environmental monitoring, agricultural diagnostics and rapid site assessment in inaccessible areas.

Future work will focus on further miniaturization, improved optical efficiency, extended spectral coverage and the integration of automated spectral interpretation algorithms. International cooperation between industrial and academic partners, including Turkish and Hungarian institutions, will continue to play a key role in advancing the technology.

7. Conclusion

A fully integrated drone-based LIBS measurement system was successfully developed and validated through laboratory and field experiments. The system demonstrates reliable spectral acquisition under realistic operational conditions, confirming the viability of UAV-mounted LIBS as a practical analytical tool. The presented results represent an important step toward deployable airborne chemical sensing platforms.

Acknowledgements

The authors acknowledge the support of the Hungarian National Research, Development and Innovation Office (NKFIH) under project 2022-1.2.6-TÉT-IPARI-TR-2022-00016 and thank all consortium partners for their contributions.

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