Thermal drones are quickly becoming a widespread tool for detecting heat signatures from above.
Never before have you been able to get such accurate and cost-efficient temperature readings of commercial rooftops, wildfires, solar plants, and more. While in the past, you needed manned aircraft which were expensive and involved a lengthy scheduling process, you’re now able to hire a professional drone pilot certified in thermography to deliver the same level of data in minutes.
Drones equipped with thermal sensors become a powerful tool. They can maneuver difficult environments like tall roofs and large industrial sites to detect hot and cold spots and collect exact temperature data, all while keeping pilots at a comfortable and safe distance from the action.
Table of Contents
Whether you want to invest in thermal drone technology for your business or you’re a drone pilot yourself, this article will teach you what a thermal camera is, how they are used in the drone industry, what qualities to look for in a thermal camera, how to take care of one properly, and the most popular thermal cameras for drones out there.
So let’s get started.
What is a Thermal Camera?
At the most basic level, a thermal camera detects heat energy. It senses infrared radiation (IR), which means waves from 1 to 14 micrometers on the electromagnetic spectrum. Unlike visible light, which ranges from 0.4 to 0.7 micrometers in wavelength, infrared waves cannot be seen by the human eye. We can only feel them by the heat they emit.
The images produced by thermal cameras allow you to see how much heat radiates off an object. Typically, the temperatures are color-coded. Colder temperatures show in shades of blue, purple, and green, while warmer temperatures are represented by shades of red, orange, and yellow.
Thermal cameras come in various forms. For example, they can be handheld devices or a part of screening detectors at airports. But they can also be attached to vehicles like drones for increased mobility.
Image Source: Wikipedia
Introduction to Thermal Cameras for Drones
When attached to a drone, thermal cameras can capture thermal information on large geographic areas. And with that data, thermal drones can produce detailed heat maps that can help you detect hot and cold spots.
To do this, a drone thermal camera has a special lens through which IR frequencies can pass. From there, the radiation travels through a thermal sensor and then an image processor to deliver the actual thermal image.
It’s also important to note that many outside factors influence a drone’s thermographic reading. For example, surface conditions like an object’s reflectivity and transparency can have a major impact on how accurate the thermal data is. Other factors include air temperature, weather, humidity, time of day, camera distance and angle, and how smooth or rough the target surface is.
Video Credit: Teledyne FLIR
“Using the thermography drone, we can provide our customers with inspection services for large buildings and photovoltaic systems, which were not previously possible.”
- Rolf Rutzer, Krüger + Co. AG
Common Uses for Drone Thermal Cameras
Ever since thermal cameras were developed for drones, people have been using them in a variety of ways from commercial applications and public safety.
Here are some of the most common use cases:
1. Firefighting
Thermal drones can quickly detect house and forest fires and identify their hottest spots. They have the ability to see through smoke and poor lighting conditions. And after a fire, drones can provide critical damage assessments. All this helps keep firefighters out of harm’s way as much as possible.
Video Credit: CNET
2. Power Line Inspections
With the help of thermal sensors, drones can detect electrical issues in power lines. This not only provides highly accurate inspection data at a fraction of the traditional power line inspection cost but also allows workers to stay on the ground out of harm’s way.
3. Roof Inspections
From residential houses to large commercial buildings, roofs need frequent inspection for detecting inefficiencies from things like heat leaks. Drone thermal cameras can help detect these to make sure roofs stay in top shape and free of critical safety hazards.
4. Search and Rescue
Drones can help locate missing people by detecting their body heat. They can assist law enforcement by gathering real-time intelligence on both victims and criminals. Not only can they deploy more quickly than a traditional ground crew but they can cover vast amounts of land by flying at speeds up to 60 MPH (100 km/h) from hundreds of feet up. This way, you can drastically cut down on the time it takes to perform successful search and rescue missions.
5. Solar Farm Inspections
Thermal drones can inspect solar plants to make sure they are running at peak efficiency. By absorbing the heat waves that reflect off solar panels and other equipment, they can easily detect anomalies that need to be fixed. This saves asset holders money and resources in the long run and helps them take full advantage of their solar panel warranty claims.
As thermal drones continue to develop, we will see more and more industries use them for good. Whatever your business, there’s probably at least one way it could benefit from thermal drone technology.
Qualities of Drone Thermal Cameras
That said, there are some important qualities to consider before choosing a drone thermal camera. Here’s what you should look out for:
- Fixed Mounts. These keep the thermal camera from being removed or swapped out from the drone. They are ideal if your drone only ever needs one camera, like the Mavic 2 Advanced.
- Attachable Payloads. Unlike fixed mounts, attachable payloads are cameras that can be removed, like the Zenmuse H20T. If you ever need to swap out your thermal camera for a different sensor, this may be the better choice.
- Dual Sensors. Dual sensors combine a regular RGB camera with an infrared sensor in one device, like the Zenmuse XT2. This way, you can seamlessly toggle between optical and thermal imaging.
- Resolution. The higher the thermal camera resolution, the more pixels will be on each image. The two most popular resolutions for thermal drones are 336 x 256 and 640 x 512.
- Gimbal. The gimbal stabilizes the thermal camera as the drone flies. Without it, the drone footage would constantly shake.
- Radiometric Functionality. Advanced thermal cameras give you radiometric data that tells you the exact temperatures of objects instead of just how they contrast with surrounding temperatures. This way, you get precise temperature readings.
- Lens Focal Length. The focal length gives the angle of view and is measured in millimeters (mm). The wider the lens, the lower the focal length and magnification. The narrower the lens, the higher the focal length and magnification. Many thermal drone cameras have fixed focal lengths of 13mm or 19mm.
- Transmission Frequency. Thermal drones usually transmit footage at a 9 or 30 Hertz (Hz) frequency to the controller. Just know that at 9 Hz, videos will result in a choppier video feed compared to 30 Hz cameras.
Video Credit: RMUSUAV
Thermal Camera Care and Maintenance
To keep a thermal camera in good condition, you’ll want to make sure you take care of it properly.
Clean the lens if it gets dirty. But make sure to follow manufacturer guidelines closely and use extreme caution. Some cleaning materials like microfiber cloths can actually permanently damage the lens. It’s better to use a lens cleaning brush with a lens cleaner fluid that is 96% ethanol alcohol.
When operating the thermal camera, never point it toward the sun or at high-intensity lasers as these will damage the detector by destroying pixels in it. This is especially true for uncooled detectors. They simply can’t handle absorbing high energy sources.
Also, store the thermal camera in a hard case and away from dust and extreme temperatures. That way, it stays protected from damage while you’re not using it as well.
Most Popular Thermal Cameras for Drones
These days, there are several thermal camera models for drones. This means you have a lot of selection, but shopping for one can be daunting as well.
So to get started, here are some of the most popular models out there:
- Zenmuse H20T. This is a dual camera that has both a 20 MP zoom camera and a 640 x 512 px radiometric thermal camera. It’s perfect for enterprise-grade drone operations. But it also comes with a hefty $11,800 price tag.
- EVO II Dual R. This is a fixed payload that features a 48 MP camera with an uncooled IR sensor that picks up infrared radiations of 7.5 to 13.5 micrometers. You can get the whole drone for $10,499.
- Zenmuse XT2. This camera is no longer in production, but you can still buy it used. It’s another dual camera equipped with an uncooled thermal imager that has a 7.5 to 13.5 micrometer spectral band.
- Mavic 2 Enterprise Advanced. This drone comes equipped with a fixed dual camera that has a 640 × 512 px radiometric thermal camera with a 30 Hz frame rate, 16x zoom, and 640 x 512 resolution.
- FLIR TZ20. This thermal sensor is made in the USA, but it was discontinued. It offers two 640 x 512 non-radiometric cameras with a 5x optical zoom. You can find it for anywhere from $5,500 to $7,500.
- ANAFI Thermal. The ANAFI Thermal drone comes equipped with a fixed FLIR Lepton 3.5 radiometric sensor for exact temperature readings with a spectral band of 8 to 14 micrometers and a photo resolution of 3264 x 2448. At a price of $1,999, this drone is one of the most affordable thermal camera drones out there.
Video Credit: Aerial Influence
Next Steps: Getting Started with Thermal Drone Services
Now that you know the basics of drone thermal cameras, you can take your business operations to the next level by outsourcing your thermal inspection needs to a professional drone service.
Here at The Drone Life, our pilots can help you inspect anything from solar plants to roofs with enterprise-grade thermal drones. Our expert team is professionally trained in thermography and has years of experience in helping clients perform aerial inspections. Feel free to schedule a free consultation with one of our drone experts today.
