New Firefighting Robot Uses Cryogenic Spray, Could Fight Wildfires

Northeastern University researchers have developed a firefighting robot that uses liquid nitrogen spray to extinguish small fires and hotspots before they escalate into major wildfires. The prototype, built with student help, features a liquid nitrogen tank, spray hose, and all-terrain caterpillar tracks. Professor Yiannis Levendis explained that the rapid evaporation and expansion of liquid nitrogen upon contact with flames creates a cooling effect, suffocating the fire almost instantly.

Unlike traditional wildfire retardants, the cryogenic system leaves no chemical residue. The robot, which can be operated remotely or potentially autonomously, is currently being tested on controlled fires using forest fuels common in the western United States. Tom Ryden, executive director of MassRobotics, sees potential in using such robots to enter dangerous areas, reducing the risk to human firefighters.

Levendis also envisions scaling up the technology for larger firefighting vehicles. However, significant engineering hurdles remain, including cryogenic storage, transportation logistics, and the amount of nitrogen needed for extended firefighting. If the approach proves practical, robots could complement existing wildfire suppression methods by targeting small ignition points in hazardous terrain.