Drones and Thermal Imaging Explained

September 15, 2023

Drones have many uses, one of which incorporates thermal imaging technology. These special cameras detect heat given off by a subject using infrared technology. See below for a more detailed explanation of how drones are contributing to analysis of bridges, agriculture and law enforcement by “seeing” the heat footprint of an object using drone aerial observation.

Types of Thermal Cameras

  1. Forward-Looking Infrared (FLIR) Camera:
    • FLIR cameras are commonly used in thermal imaging drones. They can capture thermal images in real-time and provide temperature data for different objects within the scene.
    • These cameras are often mounted on gimbals, allowing for stabilized imaging even when the drone is in motion.
  2. Radiometric Thermal Cameras:
    • Radiometric cameras provide temperature measurements for each pixel in the image, allowing for precise thermal analysis and temperature mapping.
    • They are useful for applications such as building inspections, where identifying temperature variations is critical.
  3. Multispectral Cameras:
    • Some drones may use multispectral cameras that capture both thermal and visual (RGB) images simultaneously. These images can be fused to provide more comprehensive information for analysis.
  4. Thermal Imaging Attachments:
    • In some cases, drones may support thermal imaging attachments or modules that can be swapped out to adapt to different thermal imaging needs.

How Thermal Technology Works

Thermal imaging cameras work by detecting infrared radiation (heat) emitted by objects and converting it into a visible image. Here’s a simplified explanation of how this technology works:

  1. Infrared Sensors: Thermal cameras have arrays of infrared sensors, often made of materials like microbolometers. These sensors can detect the heat emitted by objects in the form of infrared radiation.
  2. Heat Detection: The sensors measure the temperature of objects by detecting variations in the intensity of infrared radiation. Warmer objects emit more radiation, while cooler objects emit less.
  3. Image Processing: The data from the sensors are processed to create a thermal image. Each pixel in the image corresponds to a temperature measurement, and the camera’s electronics convert this data into a color-coded image, where different colors represent different temperatures.
  4. Display: The resulting thermal image is displayed on a screen, often with a color palette that assigns colors like red, orange, yellow, green, and blue to different temperature ranges.
  5. Analysis: Thermal images are analyzed to identify temperature variations, locate hotspots, or assess thermal patterns, depending on the application.

In Summary

Drones equipped with thermal imaging cameras provide valuable insights by allowing operators to see heat signatures that are invisible to the naked eye. This technology is particularly useful in fields where temperature differences can indicate issues, such as equipment failures, structural defects, or health problems in plants and animals.