Combining simple sensors to solve a complex problem
- Researchers at the Institute for the Protection of Terrestrial Infrastructures, the Hochschule Bonn-Rhein-Sieg and the Ludwig-Maximilian’s-University Munich have developed the prototype of a mobile explosives detector.
- It detects energetic materials library-free, regardless of their chemical composition.
In 170 experiments, the detector provided the correct information about the explosive capability of the respective sample examined in 99.4 percent of the cases. The detection algorithm was based on 13 explosive and 4 non-hazardous materials. They were selected to cover the most common chemical classes. Among them were also „benign“ materials that could easily be mistaken for explosives either visually or due to their chemical nature.
To ensure that the prototype would correctly detect explosives without access to a database, further tests were carried out. The detector should recognise substances that were not involved in the development of the underlying detection algorithms. The prototype was also able to correctly assign these substances, which were „unknown“ to the system, to the classes „non-hazardous“ or „explosive“ in 9 out of 10 cases.
Self-developed gas sensors shorten detection time and save electricity
The detector uses specially developed metal oxide semiconductor gas sensors which, thanks to modular electronics, can be quickly replaced, for example in the event of a malfunction. Since the sensors are particularly energy-saving, the prototype is suitable for mobile, battery-operated use.
The tests showed that the prototype reliably distinguishes explosive from non-energetic substances. Thanks to the self-developed gas sensors, detection can take place in less time in the future and power consumption is reduced. In addition, the detector can provide data on the chemical class of the analysed substance – information that can be a decisive advantage for the emergency services.
The results of the study were published in the journal SENSORS and ACTUATORS B.
Autors of the Study:
Dr. Kostyantin Konstantynowski, DLR
Christoph Hammer, DLR
Oscar Hernan Ramírez-Agudelo, DLR
Gerald Nijo, Hochschule Bonn-Rhein-Sieg
Niklas Wenzel, Hochschule Bonn-Rhein-Sieg
Prof. Dr. Gerhard Holl, DLR
Prof. Dr. Thomas M. Klapötke, Ludwig-Maximilians-Universität München