Chennai: First responders entering an unknown indoor environment for search-and-rescue operations during a disaster can soon map the space by wearing a sensor. Researchers at IIT-M developed a technology called Ubiqmap to map an indoor area under any lighting or environmental conditions in real-time using radio frequency-based imaging in a technique called radio tomographic imaging (RTI). The technology is vital for first responders during disaster relief operations as traditional infrastructure often becomes unreliable during public safety emergencies, researchers said.
RTI systems use fixed wireless transceivers or sensors to map environments. These transceivers send radio signals to each other; objects or people affect the signals by weakening or scattering them. Each transceiver measures received signal strength, and changes are recorded on a computer, which then reconstructs an image of the area.
IITM’s technology uses wearable transceivers on rescue personnel that track movement and auto-update floor maps in real-time. This provides first responders with accurate indoor maps, even in low-visibility areas, aiding evacuation planning and effective resource allocation.
“Our technology offers first responders a robust and portable tool to image indoor environments without dependence on visual line of sight or extensive computational resources, making it an asset in complex scenarios,” said Prof Ayon Chakraborty, Department of Computer Science and Engineering, who led the team. An Indian patent was filed for this technology by IIT-M research team.
The researchers said the system can also estimate the material properties of mapped elements, such as distinguishing drywall from concrete or metal. This helps first responders design safe and more efficient evacuation or rescue routes in complex indoor environments. While the system can be used along with existing tools like cameras, it can also be combined with techniques like SLAM or Simultaneous Localisation and Mapping to enhance performance.
“We successfully tested the technology in a controlled setup within a few residential units at the IITM campus. We are in the process of prototyping a wearable version of the technology to prepare for field trials in real-world scenarios,” the professor said.