Engineers show how firefighting in high-rise buildings may look in the future
In October 2021, a group of engineers from the Multirobotic Systems Group at the Faculty of Electrical Engineering of the Czech Technical University in Prague presented a new unmanned aerial vehicle that autonomously fires a fire-extinguishing capsule and can act very quickly in the event of a fire in multi-storey buildings.
During an experiment conducted in cooperation with the fire and rescue service, researchers tested the drone during a simulated intervention with a split fire in an abandoned building. The drone, named DOFEC (Discharging Of Fire Extinguishing Capsules), was developed to fight fires in high-rise and multi-storey buildings.
“Using onboard sensors and artificial intelligence, the drone detects and locates the fire thanks to an infrared camera. Then, using a special mechanism, it fires a half-kilogram capsule containing a substance that draws heat away from the fire and reduces its intensity. This gives firefighters more time to reach upper floors and save lives”
According to the engineers, no similar system has been used anywhere in the world. Its creators are improving the firefighting drone so that in the future it can very accurately deliver up to six capsules into the fire at once. Precise placement of capsules through a window, which the drone will break itself in the future, has become possible primarily thanks to improved software for autonomous flight, stabilization and thermal imaging.
Robotics engineers have been working on developing this complex system since 2019. Tests in Brandýs nad Labem (a town in the Czech Republic) showed that GPS signal reflection occurred near buildings, which made it difficult for the drone to navigate at the intervention site. Therefore, for the next prototype, the MRS group plans to use onboard sensors to determine the drone's location so that it does not have to rely on the GPS signal.
Czech Technical University student Vojtěch Nidrle, as part of his bachelor's thesis, took part in developing the drone's hardware, whose production cost the researchers estimate at several hundred thousand crowns. He used a program to calculate the dimensions of propellers or batteries, and then individual parts made of carbon composites and aluminum profiles.
“During the pandemic, I built the drone in my home workshop. Waiting for parts took a long time, but assembly went quickly. The nine-kilogram drone is powered by electric motors and can stay in the air for about ten minutes”
Vojtěch Nidrle and his colleagues from the Multirobotic Systems group are already working on a more advanced prototype of the unmanned aerial vehicle, which can carry six fire-extinguishing capsules instead of one and thus is capable of fighting a fire covering an area of 60 m².
The fact that the new solution could fundamentally change how firefighters intervene in high-rise buildings was also acknowledged by a representative of the Central Bohemian Region Fire Rescue Service.
“We greatly appreciate that engineers from the Faculty of Electrical Engineering of the Czech Technical University invited us to conduct this research. We see it as the seed of a possible future that still requires refinement in several respects, not only from technical and legal points of view but also from a tactical one”
The use of drones in fire protection units in the Czech Republic has a future. Currently, firefighters use drones to observe intervention sites. Standard-configured devices are equipped with a regular camera and an infrared camera, but they are not used for firefighting.
According to Jaroslav Gabriel, due to the existing payload and the smaller volume of extinguishing agent, drones look promising for firefighting in small rooms. For large rooms, reducing fire intensity and gaining time for evacuation may prove useful. In addition to the Central Bohemian Region fire station, the Multirobotic Systems group from FEL CTU has established cooperation with its colleagues from the Plzeň Region.
The possibilities for using autonomous drones in firefighting are very promising. In addition to the aforementioned fire suppression, they can help search for people or dangerous objects (for example, gas cylinders).
The MRS Group's expertise in this area is based on experience from the MBZIRC competition in Abu Dhabi, where firefighting in a multi-storey building was one of the disciplines. The Czech team in the competition, which is considered the unofficial world championship for autonomous drones, long ranked among the absolute global leaders and won it in 2020.
“During a technically very challenging flight in a smoke-filled environment, we can rely on our experience searching underground complexes in the DARPA Subterranean Challenge, in which our drones took part as part of the broader robotics team FEL CTU”
At the recent finals in Kentucky, the FEL team won silver in the virtual part and placed sixth in the physical robot competition.
