Heat-resistant drone flies into flames to protect firefighters

A heat-resistant drone can fly into fires to collect and share important data about the blaze with human workers.

The drone, which is in development at Imperial College London and Empa (the Swiss Federal Laboratories for Materials Science and Technology), could be sent into burning buildings or woodland to assess hazards and provide crucial first-hand data from danger zones. The data would then be sent to firefighters to inform their emergency response.

The prototype device, called FireDrone, is made of a new thermal aerogel insulation material and houses an in-built cooling system to help it withstand temperatures of up to 200°C for ten minutes.

Principal investigator Professor Mirko Kovac, director of the Aerial Robotics Lab at Imperial College London and head of the Laboratory of Sustainability Robotics at Empa, said: “Until they enter the danger zone, firefighters can’t be certain of what or who they’ll find, and what challenges they’ll encounter.

“FireDrone could be sent in ahead to gather crucial information – noting trapped people, building layouts, unexpected hazards – so that responders can prepare accordingly to keep themselves safe and potentially save more lives."

Unmanned aerial vehicles (UAVs) are already used from afar in firefighting to take aerial footage, hoist fire hoses up skyscrapers, or drop fire retardant in remote areas to slow the spread of wildfires. Drones equipped with cameras and carbon dioxide (CO₂) sensors could provide crucial information about the layout and composition of fires, but current options are unable to fly closer to fires in case their frames melt or their electronics fail.

The researchers looked to animals that live in extreme temperatures for inspiration, such as penguins, Arctic foxes, and spittlebugs. They all have layers of fat, fur, or other thermoregulating materials that allow them to thrive in extreme conditions.

To build the drone, the team created a protective structural shell made of lightweight ‘super-insulating’ polyimide and silica aerogel, and glass fibres. They coated this with aluminium to reflect heat. The super-insulation prevents the materials from shrinking and pore structures from degrading after exposure to high temperatures.

Within the protective exoskeleton, the team placed the temperature-sensitive components, such as regular and infrared cameras, CO₂ sensors, video transmitters, flight controllers, batteries, and radio receivers. They also used the release and evaporation of gas from the CO₂ sensors to build a cooling system to keep temperatures down.

The researchers tested the 50cm-tall drone by flying it into a controlled “inferno” at a firefighter training centre. “Even after several flights, the electronics, thermal imaging camera and CO₂ sensors of the FireDrone are undamaged and ready for further testing,” said David Häusermann from Empa's Sustainability Robotics lab.

The team hope that further work to miniaturise and add more sensors to the drone might lead to its deployment in real-life firefighting missions and help save lives.

The device could also be used in extremely cold environments, such as the polar regions or in glaciers. The team tested the robot in a glacier tunnel in Switzerland to study how the system behaves in very cold temperatures.

Although FireDrone is at prototype stage, the researchers said it is a step forward for the development of other drones that can withstand extreme temperatures. They are now validating the technology with key industry stakeholders and partners.

Professor Kovac said: “The application of drones is often limited by environmental factors like temperature. We demonstrate a way to overcome this and are convinced our findings will help to unleash the future power of drones for extreme environments.”

The work was published in Advanced Intelligent Systems.