Drone 3D mapping: what is it and how it is used?
In this guide, we provide some pointers about mapping software, as well as how drones are used in 3D mapping and land surveying today, so you can get started if you’ve been thinking about adding mapping to your skills.
In a variety of commercial settings, drones can be used to map large areas quickly and effectively in a cost-effective manner.
Useful links : Thermal imaging services of buildings
Until recently, the only way to get an aerial photogrammetric map with high accuracy and resolution was by flying manned aircraft over the area of interest or having access to spy satellites. With the advancement of drone technology and their decreasing costs, high-quality aerial maps have become more accessible to a wide range of industries and individuals.
The following industries use drone 3D mapping and simple mapping:
Construction
Using drones for mapping in the construction industry has also proven to be highly beneficial. In the construction sector, maps can be used for regularly updating clients, analyzing raw material stockpiles, and creating 3D models of construction sites. As a result of these maps, construction managers are able to gain a better understanding of the “big picture” and make more strategic decisions.
An overview of land surveying
The use of aerial mapping by land surveyors is obvious. Boundary measurements are taken on pieces of land by these professionals. Using the data that they collect, they are able to create maps, plots, and legal documents that can help to resolve legal disputes. Drone photogrammetry can make a massive difference to their profession since maps are a crucial part of their work.
Surveyors used to find it extremely difficult to convert a highly accurate map into a 3D topographic map with contour data using photogrammetry. Drones provide surveyors with an efficient way to do their job, expediting their workflow and improving their bottom line, thanks to their expertise and high-quality equipment, such as RTK GPS units.
Those providing drone mapping services should be aware that many solutions are capable of producing “survey grade” maps. Unless you are a licensed surveyor or work with/for one, you should not advertise that you provide “survey grade” results. Learn more about your state’s land surveyors board if you would like more information about these laws in your area.
Commercial and residential real estate
When it comes to the sale of land, aerial maps can be a valuable tool that aids in the process. In the case of large tracts of land, an aerial map can be of great value, especially when determining if the property is the right one for them. Almost everyone has experienced the lack of detail that is often found on a standard satellite image if they have ever looked at one.
There is a solution to this problem of clarity through drone mapping. By using an aerial map with extremely detailed information, a client can gain a better understanding of the property details without physically having to be at the property. The imagery can even be overlaid with contour lines and accurate borders with the assistance of a licensed land surveyor. Due to its ease of use and the fact that it was made (in part) specifically for work in the real estate sector, DroneDeploy is a good software option for real estate professionals.
The mining industry
Mining is currently one of the industries that are already embracing the use of drones to map their operations. There are a number of uses for detailed and up-to-date maps, such as managing stockpiles, water drainage, erosion detection, pit and dump management, among many others. A constantly updated map can aid managers in making better decisions by providing them with a better understanding of the situation.
Drone 3D mapping: The inspection process
There is no doubt that the inspection aspect of the UAS industry has become an essential part of the industry, as you may already know. A drone pilot typically uses a camera to visually inspect the equipment, although photogrammetry can also aid in the inspection process. Using drones, you can create a detailed roof map, and RGB and IR sensors can measure insulation coverage and leaks.
Using aerial maps, the energy industry, for example, can detect problems in solar panels on a larger scale, using infrared imagery to identify problem spots. Inspecting work can be done with Raptor Maps or DroneMapper software.
The agricultural industry
Drone mapping has the most significant potential in the agriculture industry. Currently, it is predicted that agriculture will be the biggest use case overall for unmanned aerial systems in the near future. Farmers can analyze their crops quickly with maps and gain access to crucial data to guide their decisions. In real-time, farmers can determine the health of their fields by using NDVI imagery with proper training.
In comparison to walking the field with a tractor or pointing out trouble spots with a drone, a drone can produce a map and identify trouble spots semi-automatically. In other words, those in the agriculture industry will have the ability to save time, increase crop yield, and thus, improve their bottom line in the long run. DroneDeploy with its Field Scanner application, Precision Hawk’s Precision Mapper, and Pix4D’s PIX4DAG software are some of the significant drone companies focused on agriculture.
In forestry
It is also possible for the forestry industry to benefit from drone mapping. It is possible to detect and track illegal logging with the help of detailed maps, determine the number of trees in the forest, and monitor the forest’s health with the help of detailed maps.
It is possible to monitor areas of dry vegetation with NDVI imagery, which can assist in the prevention of forest fires. In addition to identifying dead trees, mapping can also help reveal whether the forest might be suffering from a disease that may be affecting it. There are countless other items on the list.
The Management of Emergency Situations
In the event of a disaster, emergency management needs accurate and quick information as soon as possible so that it can effectively respond, primarily if the disaster affects a large area. In the case of a disaster (such as a flood or hurricane), officials can use drone photogrammetry to determine the most severely damaged areas.
They are able to effectively distribute their resources based on this data to respond in a timely manner to any emergencies that arise. During Hurricane Harvey, Hurricane Irma, and other hurricanes in 2017, drones were used in disaster relief efforts, including search and rescue, and drills were used to make detailed maps for disaster relief in Houston, Texas, and elsewhere.
Drone 3D mapping: Terminology for Key Mapping
Now that we’ve covered use cases, let’s cover key terminology in mapping (and drone 3D mapping.).
Photogrammetry: is the process of measuring the dimensions of structures by using photographs, usually aerial photographs.
Orthomosaic: In an aerial image, the scale of the image is uniform throughout, regardless of topographic relief, camera tilt, or distortions in the camera optic.
RGB Camera: In mapping, this type of camera is traditionally used. The image is created by taking samples of Red, Green, and Blue light spectrums.
NDVI
A modified RGB or near IR sensor produces a derived image, also known as Normalized Difference Vegetation Index. Plant reflectivity is ranked on a scale of -1 to +1 using the NDVI. Plants with a higher amount of reflective light correlate with a healthier plant, as their chlorophyll is what reflects light (unhealthy plants have low amounts of chlorophyll, so they reflect less light).
To analyze crop health, NDVI is a valuable tool for agricultural professionals. The NDVI provides helpful information to end-users. However, it must be properly analyzed and ground-truthed. In most cases, NDVI maps are not beneficial to the end user but are used by crop specialists to monitor crops.
Ground Control Point (GCP)
The purpose of this marker is to maintain the accuracy of your map’s geographical location. GPS (or other GNSS systems) coordinates are used to identify the location of a GCP. You can align your whole map correctly with the surrounding geography with this very accurate coordinate. It ensures that one point on the image aligns with a precise GPS coordinate on the earth. A survey-accurate map must compare well with an older map, be overlaid over different remote imagery, or be used for comparisons with older map data.
Near-Infrared
Light with a wavelength that is slightly below that of visible light (electromagnetic radiation). It is possible to determine the health of a plant by measuring the NIR light reflected off it. It is necessary to use a special NIR camera, multispectral camera, or modified RGB camera in order to obtain this information.
Infrared
Long-wavelength (lower frequency) infrared radiation is electromagnetic radiation or light. Infrared is useful for detecting heat.
Thermography
A thermogram is an image captured by the infrared spectrum of light. Heat imagery is often used in industrial applications to show areas of heat within an object. Drone pilots can earn money by doing thermographic work, which is in demand.
Real-Time Kinematic or RTK
GPS (or other GNSS) data is used in real-time kinematic satellite navigation to achieve centimeter-level accuracy. A GPS radio signal is analyzed by the RTK receiver in order to calculate this data. It is a big deal to have RTK on your drone – an RTK receiver on your drone negates the need for a ground control point.
Point Cloud
In computing, a point cloud is a collection of points or coordinates on the surface of an object. These points can be used to create a 3D model of an area. LIDAR and photogrammetric data are commonly used to generate point clouds.
Relative Accuracy
The relative accuracy of a map refers to the accuracy of one point in relation to another. The X cm distance between two points on a map should correspond to their real-world distance.
Absolute Accuracy
Absolute accuracy is the accuracy with which a point is measured in relation to a real-world coordinate. In order for a point to be considered absolute accuracy, its GPS coordinates need to match those on the map.
Resolution
Detailed maps are referred to as high-resolution maps. Every pixel on the map will be represented by X amount of CM, which is commonly measured as CM/Pixel.
We hope you have enjoyed this guide and learned the basics about drone 3D mapping and mapping using drones in general.
Follow Sky Condor on Twitter
