Robot-assisted examinations of improvised explosive devices (IEDs) – interview on the DURCHBLICK project

“Explosives or soap?” – researchers at Fraunhofer EMI work on imaging techniques for the examination of potentially dangerous objects

An interview with Dr. Stefan Moser and Victoria Heusinger

As part of the two-year German-Austrian research project DURCHBLICK, Dr. Stefan Moser and Victoria Heusinger are working on robot-assisted examinations of improvised explosive devices (IEDs).

© Fraunhofer EMI
An interview on the project DURCHBLICK with Dr. Stefan Moser (second from the left) and Victoria Heusinger (third from the left).

What are the contents and objectives of the project DURCHBLICK?

Moser: The bilateral project DURCHBLICK mainly deals with the robot-assisted application of sensor technologies by task forces to examine potential threats. The motivation for the project is the increasing dissemination of instructions for preparing improvised explosive devices (IEDs) on the internet and the increasing number of incidents where, because of a suspicious object, for example, a station concourse has to be closed. Some of the potential sensor technologies for examining these kinds of objects are not yet mountable on a robot platform and as such remotely controllable by the task force teams. By integrating these technologies on a robot, however, bomb squads will have a better tool to help assess situations of danger. Fraunhofer EMI coordinates this German-Austrian research project besides working on its own research topics. I am the coordinator and Victoria Heusinger is the internal project manager for the EMI research topics.

So, this research is not about the disarmament of explosives but about how to gain information on suspicious objects?

Moser: Exactly. We are working on improving the potential of data generation and processing so that bomb squads have the best possible data basis to work with and plan their next actions.

Heusinger: The gained data can be used as forensic material too, which is used to help identify potential perpetrators after the dangerous object is cleared.

Regarding the name DURCHBLICK (English: looking through something): What exactly are you looking through, and what do you get to see?

Heusinger: It is of particular interest to be able to look into suspicious objects in order to confirm or disprove a potential danger of explosives. A typical scenario is a conspicuous piece of luggage left in a train station or airport that is categorized as potentially dangerous for the surrounding area. Exact information has to be gathered on whether there are potentially dangerous materials in the object, be it pyrotechnical explosives or a bomb, and on how they are positioned. The challenge is to identify the explosive charge and to differentiate between real explosive charge, a dummy charge or the surrounding concealment objects.

What topics will you be addressing to achieve this research goal?

Moser: We want to utilize various technologies for robot-assisted applications. We, as the German part of the consortium, are addressing the imaging techniques of X-ray backscatter technology and gamma cameras. Our Austrian colleagues are examining the chemical analysis methods of suspicious objects. The considered technologies are not new, but they have not been designed for application on a robotic platform. We are facing a number of challenges in this area – from engineering aspects regarding the integration of the components and the control of the device to the planning of the software interfaces and the visualization of the acquired data.

Heusinger: The technologies themselves are advanced and adapted by our technology partners such that they become available for the planned application. We have an SME partner for the hardware integration in the robot as well. The main focus of EMI is on data processing, particularly data fusion. We are also dealing with measurement planning, the management of measurement campaigns and in cooperation with the SMEs we are developing the software interfaces.

© Fraunhofer EMI
Victoria Heusinger, EMI project manager, describes possible scenarios.

Why and how is the X-ray backscatter technology applied in your project?

Moser: For the common transmission radiography, you need access to the object from both sides in order to be able to place the X-ray source in front and the detector behind it. For the project relevant objects of investigation, this setup is often impossible, for example, if the piece of luggage is situated in a corner or lying flat on the floor. During the X-ray backscatter process, the object is illuminated with X-rays as well, only the detector is not positioned behind the object but on the same side as the X-ray source. A finely focused X-ray beam, or a “pencil beam”, scans the object. It penetrates into the object to a certain depth and is absorbed or scattered, depending on the material. This means it is deflected in different directions with a lower energy and re-emits from the object in different directions including the direction in which the source and detector are located. That way, an image is building up line-by-line, which depicts the amount of backscattered radiation per irradiated spot. If the beam meets organic materials such as water, food but also explosives, a high amount of radiation is backscattered whereas it is strongly absorbed in metallic matter. Therefore, using this technology, organic materials are visualized particularly well.

How do other technologies help?

Moser: The clou is that the various sensor technologies complement each other. The classical transmission radiography emphasizes strongly absorbing materials such as potential detonators, and the X-ray backscatter system visualizes organic materials, such as explosives best.

Heusinger: However, at this point it is not yet possible to tell whether an organic material really is an explosive or merely a piece of soap. The chemical analysis tools developed by our Austrian colleagues can be employed for further examination of the material properties.

Moser: Using the gamma camera, it would also be possible to detect radioactive materials and their spatial distribution. Sadly enough, we have to be prepared for such scenarios as well.

In what way can you draw on EMI expertise?

Moser: X-ray technology has been an area of interest for EMI for quite some time, especially the methods of learning as much as possible about the examined object from only very little information – the X-ray images. At EMI, X-ray imaging is used for the examination of specialized aspects, be it for container screening in the project ECSIT, airport security projects or for X-ray-based examination of car crashes in our crash-test facility. Of course, our experience in managing such research projects is also beneficial.

Heusinger: Beyond that, we also have expertise in the experimental setup of our experiments and test objects, the IED imitations as well as pieces of luggage.

Moser: Also, there is exchange within the Fraunhofer-Gesellschaft: For example, the project “IED Inspector” (German: USBV-Inspektor), which was managed by the Fraunhofer FHR, examined the terahertz radar technology for its usage when access to an object is limited. This technology complements ours very well by providing 3D information on the object.

Heusinger: We are building on the results of this project and have adapted the choice of scenarios to examine correspondingly. The Fraunhofer FHR and thereby IED Inspector are directly involved in our project as associated partners.

How can we imagine your work with scenarios?

Moser: We choose scenarios relevant to everyday life in collaboration with end users such as the State Office of Criminal Investigations (LKA), the federal police force, and the Federal Criminal Police Office (BKA). According to this, we prepare demonstration objects with IEDs next to the usual contents such as clothes, toiletries or electronic devices and then examine what we can identify using the various sensor technologies and if it is possible to allocate the relevant objects to the IED.

Heusinger: Different scenarios require different pieces of luggage: suitcases, briefcases, backpacks, handbags, toolboxes. Also think of pyrotechnical explosives hidden in vending machines or smaller explosives wrapped in newspaper and lying in the dispenser shaft of an automat. Generally, all everyday objects with signs of manipulation could be included in a scenario.

© Fraunhofer EMI
Dr. Stefan Moser, project coordinator, explains various X-ray setups.
© Fraunhofer EMI
In the project DURCHBLICK, EMI is working on the robot-supported implementation of sensor technologies for security forces.

Have you ever seen an application of this in real life?

Heusinger: No, and that is not planned either. We, as observers, would be a possible hindrance during such an incidence.

Moser: A little anecdote to that: At the LKA in Stuttgart, I was allowed to operate a disarming robot. As part of the experience, I had to steer it out of the room where I was, through two hallways and into a different room to look if there was something suspect on top of a closet. I thought I would be able to complete the task quite easily since I have a bit of experience with remote steering. 20 sweat-filled minutes later, I had just maneuvered the robot in front of the closet and yet, I still had to maneuver it to the correct position, which also took quite long. The orientation within the room is lost when you are working with only a few cameras on the robot itself. To think that in a real-life situation, a distance of perhaps 50 meters and maybe even hurdles such as stairs need to be dealt with, and that you might realize, for instance, that the robot is equipped with the wrong sensors, while each extra minute possible endangers lives and costs money – this makes one quite nervous. That is why it is crucial that the information gathered by the robot is easy to record and that the sensor control system is reliable. It is also important that the robot is properly equipped, so that it does not have to be brought back between tasks. From an engineering point of view, this is a very interesting aspect.

How is the bilateral and interdisciplinary cooperation with the various project partners working?

Heusinger: The partnership with Austria is advantageous since our technology standards as well as ethical and legal aspects are very similar. In that way, we complement each other very well.

Moser: This is what our cooperation is existing on. We coordinate with each other in regular meetings so that we are building upon each other’s findings and so that those findings are compatible. Regarding the overall assessment, the various project partners address different aspects. These include ethical and juridical questions regarding the framework conditions, the hardware integration or how to ensure for each respective technology that the necessary interfaces exist and are applicable on a robot and that the data is correctly compiled, saved and presented meaningfully. This is only possible via exchange and communication between partners.

Heusinger: It is exciting to think outside the box and gain new perspectives on the same topic from different research fields. Questions arise that you would not have thought to ask before, and you gain a lot of knowledge, not only in a subject specific or technological context.

How does international cooperation work in security research? Is there competition between the actors?

Moser: The greatest competition would have been the project IED Inspector. However, we integrated their results and experts into our project. In order to reach our goal of developing a useful tool for the end user, we wanted to get all relevant actors on board.

Heusinger: There is international cooperation and networking within security research, often in form of workshops or conferences. In March for example, I was at the Border Security Expo in London. Of course, information can only be exchanged to a certain extent. Nevertheless, cooperation in security research is strongly tied to trust and honesty. That is a key difference compared to other research areas.

How safe do you feel in public areas such as airports or train stations?

Moser: Our research has made us realize how important and challenging the tasks are which our security forces undertake on a daily basis, and how much effort is put into ensuring public security. I have great faith in these measures. For me, this boosts my personal motivation to do outstanding work. To answer your question directly: I am not afraid, as I can assess possible dangers and am less likely to panic.

Heusinger: Unfortunately, one cannot foresee and plan for everything. We have known that since 9/11. However, what we can see is how much research is performed. Especially the German Federal Ministry of Education and Research (BMBF) is investing a lot of money to look into the newest research questions and explore solutions for possible dangers. What can be done will be done, concerning security research.

What comes after the DURCHBLICK project?

Moser: The next step is to set the course for a sound application of the project so that from the demonstrator a product can be developed soon. Firstly, the end users should be able to use a system in a real scenario that is more powerful and efficient than the devices that are currently available. Secondly, our project partners, especially the SMEs, need to get the chance to commercially implement their work by participating in the production and selling of the new products – for example, an accessory device for a bomb disarming robot. For us at EMI, it is an exciting technological question how we can support the end users during the image processing using computer algorithms. Beyond that, upon completion of the project, our robot also could be used on our explosives testing ground in Kandern. Our operating personnel and explosive experts at EMI would certainly profit from that.

Heusinger: Besides, through the project we have been introduced to X-ray backscatter as a technology, which is still new to us. We now start developing ideas how we could implement this technology in other typical EMI research topics such as the visualization of cracks in buildings.

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Project name

Detection of various improvised explosive devices with help of intelligent analytical sensor technology (DURCHBLICK – Detektion unterschiedlicher unkonventioneller Spreng- und Brandvorrichtungen mittels intelligenter analytischer Sensorik)


Research for civil security, announcement of “Civil security – anti-terrorism aspects and activities”, Federal Ministry of Education and Research (BMBF)

Total funding

1.3 million euros

Project duration

Two years, May 2017 to May 2019

Further information on the research topics, project partners, associated partners and the Austrian partner project can be found at