Drones are amazing devices. Besides being fun to fly, drones are now more widely used in the commercial sector due to technological advances. One area where they are increasingly being used is photogrammetry. photogrammetry drone is used in various industries to create detailed maps and 3D models.
there are a lot of Drones for photogrammetrysome are designed for this specific purpose, but most are possible because they come with high-end cameras, GPS modules and autonomous flight modes.
Whether you’re a professional drone pilot looking at ways to generate revenue, or a business owner looking to harness the power of drones through photogrammetry, this article will help you understand what drone photogrammetry is and how it can be used in various industries. Find out how it’s used.
What is drone photogrammetry?
So, in a nutshell, photogrammetry is the science of using photographs to record measurements of physical objects and areas of land.
Drone photogrammetry takes high-resolution photographs of an area from different angles and altitudes. These images are processed using specialized software to create 2D maps and 3D models of him in the area.
The more images you can capture with at least 70-80% overlap, the more accurate your data will be. To get the best and most accurate data, you need a GPS-enabled drone with autonomous flight technology and high-definition cameras. All captured images are embedded with drone GPS data that helps create accurate maps and 3D models.
Traditional methods of photogrammetry are a time-consuming, costly process and can even be a health hazard, especially when hazardous terrain has to be mapped. But with the help of high-end drones, via rovers and landscanners, he can complete what used to take him a week much faster and safer.
Most advanced drones are equipped with professional-grade cameras like those from DJI and Autel Robotics, making it easy to capture high-resolution images at low altitudes, and create 2D maps and 3D models to produce better data. can provide
Photogrammetry drones can be used in a variety of industries, including: construction, Agricultureaggregation, and Environmental monitoringIt can be used to create precise maps of large areas, monitor the progress of construction projects, analyze crop health, and survey hard-to-reach areas. Using drones for photogrammetry has made the process faster, more accurate, and less costly than traditional methods.
Is drone photogrammetry accurate?
With the right equipment and processing software, drone photogrammetry can achieve sub-centimeter levels of accuracy.
Note that drone photogrammetry accuracy can be affected by external factors such as weather conditions, GPS signal quality, and obstacles in the environment. Therefore, it is important to consider these factors when planning your project and take steps to minimize their impact on data accuracy.
Overall, drone photogrammetry has proven to be a highly accurate and efficient method for mapping and surveying large areas, revolutionizing the way spatial data is collected and analyzed.
For an independent analysis of how accurate drone photogrammetry is, Read this article from Canadian Science Publishing.
Photogrammetric Drones – Multicopter or Fixed Wing?
Therefore, there are many options when choosing a drone for photogrammetry. The first thing you want to decide is whether you want a multicopter drone or a fixed wing drone.
Both the pros and cons, and which one is right for you, comes down to many factors, such as the size of your project, the data you need to capture, your budget, and your overall skill level in flying a drone.
Multicopters are the most popular type of drone, so there are more options in this category, and they are cheaper than fixed-wing drones. Multicopter drones typically have four rotors, but some come with six to eight rotors, and these drones vary in size and weight, but are relatively easy to fly.
Popular multirotor drone brands include DJI (obviously), Yuneec, Autel, and Parrot. DJI has a number of drones suitable for photogrammetry, but the rest are 1-3.
Multicopters take off and land vertically, so they are highly manoeuvrable and do not require a large space to fly. It also hovers very precisely, maneuvers up and down with ease, and orbits around points of interest with little trouble. This makes it ideal for surveying and 3D modeling.
Another area where multicopters could be more useful is their ability to carry higher payloads. This is an advantageous feature that fixed-wing drones do not have and is useful when you need to attach heavy or multiple items to the drone.
One area where multicopters were seen to lag slightly behind fixed-wing drones is overall flight time. However, this has improved with better design and technological advances. For example, the DJI Matrice 300 RTK has a flight time of 55 minutes, which is on par with a fixed-wing drone.
However, in most cases, multicopters have short flight times, so if your project requires a drone that can operate for a long time, many flights may not be the most cost-effective option. . in order to properly complete the mission. Another area that falls short is overall coverage, but many high-end multicopters come with better batteries to extend coverage, so this has also improved.
As for fixed-wing drones, these are expensive compared to their multicopter counterparts, are difficult to operate, and require a little more training to fly. there are not many.
Those manufactured for commercial purposes are more than capable of capturing map and 3D model data. Its long flight time is one of the reasons it is preferred for large projects, and its design allows it to operate in windy conditions.
There are some hybrid fixed-wing drones that offer the versatility of multicopters and retain the robustness and power of traditional fixed-wing drones.
These are called vertical take-off and landing (VTOL) drones and have similar capabilities to multicopter drones.
The best drones for photogrammetry
There are many drones that can produce accurate data for detailed maps and 3D models. Some stand out from the rest because they are designed for commercial use.
When investing in a drone for photogrammetry, there are a few features to look out for, but one of the most important is the camera.
The camera should have a high resolution, preferably with a sensor capable of capturing images of 20MP or better, but anything above 12MP should also suffice. The higher the pixel rate, the more accurate the image when calculating ground sampling data (GSD).
GSD is essentially a pixel-level representation of real-world measurements in an image, and the lower the GSD, the more accurate the data. For example, if an image represents his GSD of 5cm, this means that all pixels in that image are actually equal to 5cm.
So if your drone comes with a camera with high resolution and a large sensor, this will allow you to capture more image data in every shot, improving the accuracy of your maps and surveys.
To learn more about GSD and its importance in drone mapping and surveys, read this excellent article from Aero Propeller.
Another thing to consider about your camera is whether it uses an electronic or mechanical shutter. Drones with electronic shutters can experience motion blur and rolling shutter effects. This distorts the image and makes it difficult for photogrammetry software to stitch the images together accurately.
Buying a drone with a mechanical shutter eliminates this distortion and improves image quality.
We recommend that you consider purchasing drones that are compatible with different types of cameras. This is especially important if you are a drone service provider and don’t want to limit your services to just one industry.
Most drones come with a standard RGB camera, which is sufficient for most photogrammetric purposes. However, industries such as agriculture will require multispectral or near-infrared (NIR) cameras to analyze the overall health of crops from multiple imaging his solutions.
In other industries such as energy and construction, infrared cameras help identify and analyze abnormal heat signatures.
Another important feature to consider is the drone’s overall flight time. If you want to survey or map a large area, you need a drone with a long flight time so that you can complete the project without taking too many flights.
A final point to note is GPS accuracy. All drones come with a standard GPS module to help you with your daily needs as it identifies location data within a certain range of your target. However, for mapping and surveying purposes, location data embedded in images from a drone’s GPS module is not sufficient.
Therefore, in order to obtain the most accurate position data in maps and surveys, drone professionals rely on GPS correction techniques like GCPS (ground control points) and RTK (real-time kinematics and PPK (post-processed kinematics), etc.). are used in combination to achieve centimeter-level accuracy. .
Many drones are now equipped with RTK technology, and while expensive, it is a great option if you want to create accurate maps, surveys, and 3D models.
For more information on these GPS correction techniques, read the following guides. aero propeller.
All drones listed below have the above features.
They all feature RTK systems, cameras with 20MP+ sensors, and flight times of over 30 minutes, and some drones are compatible with different types of cameras.
