Drone-based Thermal: what to know

In our eBook Beyond the Edge, you’ll learn about advanced drone-based sensing and four key sensors: thermal, multispectral, hyperspectral, and LiDAR. Read it now.

In this post, we’ve aggregated the key facts about thermal discussed in the book.

A New Perspective on Thermal Data

Thermal sensors have long helped businesses see invisible temperature data. For instance, energy companies can identify overheating equipment in plants, substations and towers during routine inspections. Or a government agency might use a thermal sensor to assess the impact of a fire on a building’s structural integrity.

Now, drones are capturing that data from a new perspective.

Thermal sensors work by measuring the relative surface temperature of objects beyond the scope of human vision. They use a specific type of resistor, called a microbolometer, as a detector in a thermal camera. When long wave infrared radiation emitted from objects strikes the thermal sensor, it heats up the microbolometer and this changes the electrical resistance. These changes are converted to electrical signals and stored as raw data or processed into thermal imagery.

Use Cases for Drone-based Thermal Data is Growing

The information gathered is useful in a wide variety of industries including agriculture, construction, insurance, energy and government. This technology can be used to gain insight into heat stress, water use, and plant metabolism by measuring canopy temperature; identify electrical issues and pinpoint the source of water leaks and more. According to Geospatial Scientist, Scott Hatcher, “The collection of thermal data using drones is relatively new. Already the use cases are becoming more numerous, and as business leaders identify more potential problems that can be solved with a drone-based solution, those use cases will continue to proliferate.”

How to Collect Thermal Data Using Drones

Flight planning is an important aspect of drone-based sensing. In order to capture quality aerial thermal images, an appropriate flight plan must be put in place. Before you take flight, allow a thermal sensor to warm up for 5 minutes. If you have breaks between flights lasting longer than an hour, perform the warm up again before returning to the air. To avoid thermal blur, keep a low flight speed (about 4 meters per second). You should also, pay attention to climate, and fly on days with optimal weather conditions. Both wind (over 15 mph) and precipitation can change surface temperatures and alter readings. Flying in high humidity (over 60 percent) will result in a haze in your source imagery.

Before leaving the field, be sure to preview the data collected with specialized software created by the sensor manufacturer. Performing a quick review allows you to identify issues such as haze caused by weather conditions.

Collected thermal data is typically output in raster (image) formats, with a choice between radiometric JPEG files and TIFF files. There is a balance here: JPEG files are smaller, but you lose information. TIFF files are very large, but contain all the raw data from collection without compression. The choice depends on your use case.

Redefine the Limits of Thermal

Organizations are overcoming a wide range of challenges by employing drone-based thermal sensing. Like those pioneering the practice today, you have the opportunity to change the way your organization collects and uses data to solve problems.

To learn more about how advanced drones, sensors, and flight operations are redefining the limits of remote sensing, read our eBook Beyond the Edge. Or speak with an expert on our solutions team today.