Les bases de la cartographie par drone - Guide du débutant (2023 Mis à jour)
With the advent of newer and more sophisticated drones, mapping with drones has become increasingly popular in recent years. Drones offer a cost-effective and efficient solution for mapping large areas quickly and accurately.
There are many different ways to use drones for mapping, and the best method for you will depend on your specific needs and application. In this article, we'll give you an overview of the basics of drone mapping and how to get started.
Table des matières
- Defining Drone Mapping
- Methods of Drone Mapping: Photogrammetry and LiDAR
- GCPs, RTK, and PPK
- Fixed-Wing vs. Multi-Copter
- What Software is needed?
- Applications of Drone Mapping
- Advantages of Drone Mapping
- Training Courses for Drone Mapping
Defining Drone Mapping
Drone mapping is the process of using drones to capture photographs of an area, which are then stitched together to create a 2D or 3D map. This map can be used for various purposes, such as surveying land, inspecting infrastructure, or even planning agricultural fields.
Mapping itself is self-explanatory – you are taking many pictures from different angles and positions and then stitching them together to create a map.
The hard part is getting accurate measurements from these photographs so that the map can be used for specific purposes, such as surveying land areas or measuring distances.
However, with the right software and some practice, it is possible to create highly accurate maps using drones. The accuracy of drone-based maps is often comparable to that of traditional ground-based surveying methods such as GPS.
Methods of Drone Mapping: Photogrammetry and LiDAR
There are two main methods of drone mapping – photogrammetry and LiDAR (Light Detection and Ranging).
Photogrammetry is the process of using photographs to create 2D or 3D maps. This is done by taking multiple pictures of an area from different angles and then using special software to stitch these photos together. The software will also calculate distances and sizes based on the photographs, which can then be used to create accurate 2D or 3D maps.
LiDAR is a newer technology that uses lasers to measure distance. A LiDAR sensor is mounted on the drone, and as the drone flies, the sensor emits pulses of laser light. These pulses bounce off objects in the environment and are then captured by the sensor.
By measuring the time it takes for the pulses to bounce back, the LiDAR sensor can accurately calculate distances. This data is then used to create 3D point clouds, which can be used to create highly accurate 3D maps.
GCPs, RTK, and PPK
To create accurate maps, it is necessary to use Ground Control Points (GCPs), which are defined points on the ground with known locations. These points are used as reference points when stitching together photographs or calculating distances from LiDAR data.
Another way to create highly accurate maps is to use a Real-Time Kinematic (RTK) system. This GPS-based system uses a base station to provide real-time corrections to the drone’s GPS signal. This allows the drone to know its exact location at all times, which can be used to create very accurate maps.
A third way to achieve accuracy is through Post-Processed kinematics (PPK). This is similar to RTK, but the corrections are calculated after the drone has flown rather than in real-time. This method can be used if you cannot access a real-time GPS signal.
Since GPS position accuracy is often restricted to around 2 to 5 meters, even at maximum satellite coverage and employing the most powerful GPS technology, ground-level correction is required for high-level mapping applications. The geographic precision of the data can be improved up to a centimeter-level by employing any of the three ways below.
This GPS-based system uses a base station to provide real-time corrections to the drone’s GPS signal. This allows the drone to know its exact location at all times, which can be used to create very accurate maps.
The abbreviation PPK stands for "Post-Processed Kinematic." It's similar to RTK in that it uses an onboard PPK module and a fixed ground base station.
In terms of technology, there isn't much of a difference between the two types. of systems. The main distinction lies in the way that the data is processed.
With RTK, the position information is transmitted in real-time from the base station to the drone. This allows for corrections to be made on the fly during the mapping process. PPK, on the other hand, doesn't transmit any data in real time.
Instead, the data is processed after the fact, using the information from the base station and the actual GPS data that was collected by the drone during its flight.
This may seem like a disadvantage, but PPK has some benefits that make it a more attractive option for certain mapping applications.
Perhaps the biggest benefit is that PPK doesn't require a real-time data connection between the base station and the drone. This means you can fly in areas without cellular coverage or another type of data connection.
Fixed-Wing vs. Multi-Copter
When it comes to drone mapping, two main types de drones can be used: fixed-wing and multi-copter. Choosing the right type of drone for the job is important, as each has its advantages and disadvantages.
Drones à voilure fixe are more efficient when flying for long periods since they don't have to constantly fight against gravity as multi-copters do. These drones are well-suited for large areas, such as fields or farms. However, fixed-wing drones are more difficult to control and are not well-suited for mapping in tight spaces.
On the other hand, multi-copter drones are much easier to control and can fly in tighter spaces. They are also better suited for taking high-resolution photographs, making them a good choice for mapping small areas or detailed structures. However, multi-copter drones have shorter flight times and are not well-suited for mapping large areas. They are also more maneuverable.
What Software is needed?
To create a drone map, you will need some specialized software. There are a few options available, but the most popular are Pix4D and DroneDeploy.
- Pix4D is powerful mapping software that can be used to create 2D maps, 3D models, and point clouds. It is compatible with a wide range of drones and cameras and offers a variety of features, such as automatic flight planning and photogrammetry. This software is a good choice for more experienced users.
- DroneDeploy is another popular mapping software that offers similar features to Pix4D. It is also compatible with a wide range of drones and cameras. However, it has a simpler interface that is more user-friendly for beginners.
- Pix4D and DroneDeploy offer free trials, so you can try each one to see which works better for you.
- Other than this, make sure you also have a good quality camera, such as the GoPro Hero 7 Black, to get started.
Applications of Drone Mapping
Drone mapping can be used for a variety of applications, such as land surveying, volume calculations, agricultural mapping, and construction site monitoring.
Construction sites are often large and complex, making them difficult to monitor using traditional methods. Drone mapping can be used to create detailed maps of construction sites, which can be used to track progress and identify potential problems.
Researchers can use drone mapping to collect data about a variety of topics, such as environmental conditions, animal populations, and natural disasters. Geologists can use modern survey technology to locate geologic phenomena, including rivers, domes, faults, and fault scarps.
They can also assist with survey planning if field people are required to physically visit certain regions. Regular drone surveys can be used to monitor vegetation growth or wildlife movement for environmental monitoring.
Land surveying is the process of measuring and documenting the physical features of a piece of land. Drone mapping can be used to create accurate maps of large areas of land, which can be used for a variety of purposes, such as property boundaries, construction projects, and environmental conservation.
Mining is a dangerous and dirty industry. Drones can be used to map mines so that workers can plan their routes and avoid potential hazards. Drone mapping can also be used to track the progress of mining operations and identify areas that need further attention.
Advantages of Drone Mapping
There are many benefits to using drone mapping, including:
Faster Data Collection
Drones can cover large areas in a short amount of time, making them much faster than traditional methods of data collection.
Detailed maps: Drone mapping can create detailed maps that are not possible to create using traditional methods.
Drone mapping can produce accurate data that can be used for a variety of purposes. Many drone mapping software programs offer an automated workflow, which makes it easy to create maps with little to no experience.
A nice camera drone may now be purchased for less than $2000. If you want to create your LiDAR system, expect to invest between $5000 and $10,000. Although not inexpensive, hiring a helicopter (and a pilot) to do an aerial survey is far more expensive.
Drones can be used to survey dangerous or difficult-to-reach areas without putting people in harm's way.
Applications for drones are constantly expanding as technology continues to develop. If you're interested in using drone mapping, there are a few things you need to know to get started. Multi-rotor drones are the best choice for mapping due to their stability and ability to carry a payload.
A good camera is also necessary for creating detailed maps. If you're looking to create 3D models or point clouds, you'll need a LiDAR system. Once you have the necessary equipment, you'll need to choose mapping software.
Various software programs are available, each with its features and capabilities. Once you've selected your software, you'll be ready to start mapping!
Training Courses for Drone Mapping
Training courses for drone mapping are also available to help you get started. These courses will teach you the basics of drone operation, mapping software, and data analysis. These courses are a great place to start if you're interested in learning more about drone mapping.
Our Commercial Drone Pilot Bundle is a wonderful place to start if you're a rookie drone pilot. This course will cover everything you need to know about becoming a commercial drone pilot, including how to pass the Part 107 certification and what it takes to launch a potentially profitable drone business.
Sign up for this basic UAV 3D mapping course on Udemy if you want to learn more specific abilities. It covers the fundamentals of drone mapping technology and includes a sample survey data processing workflow using Pix4D and AgiSoft. Drone mapping specialists differ from drone pilots in their ability to handle and present spatial data.
In the final thoughts, we can say that, to make a good mapping with a drone, you will have to consider the following: what is your purpose for mapping, what kind of data do you need, and how accurate does it need to be?
With these factors in mind, you can then look at drones and figure out which would best suit your needs. Always remember to register your drone with the FAA and get the proper training before flying!