Everything you need to know about surveying and mapping in Canada in 2022.
In recent years, drones for surveying and several other fields have proven to be powerful tools, offering both efficiency and safety gains. The surveying and mapping industry is no exception. Thanks to their ease of capturing data, drones have been integrated into various surveying works in order to perform topographic surveys, photogrammetry or even 3D mapping. This article is therefore addressed to different surveyors, whether you are a novice or experienced, the drone will offer you a real opportunity for your various survey missions. Learn everything you need to know to start analyzing drones.
What is the drone surveying service?
Topography is the most accurate way to determine different positions and/or distances between points in 2D and 3D spaces. The surveys will provide important information that will assist in decision making, from construction site planning to infrastructure design and maintenance, to cadastral property boundaries. Drones are excellent for rapidly acquiring data from viewpoints that are difficult to reach or even inaccessible to humans. When surveying difficult terrain, drones allow operators to no longer physically access and measure points in dangerous or hard-to-reach areas.
In addition, while traditional methods require careful measurement, preparation, and planning, drones can capture that same data in a significantly shorter time frame. In conclusion, drones produce better and faster results, all in total safety.
Which drone to choose for mapping and surveying?
What are the pre-requisites you need to fly a drone?
In recent years, drone piloting has become much simpler with the latest technologies that allow, for example, to stabilize the positioning of the drone, and even to program its return to its starting point in an autumn manner, but nevertheless a control of your device must be carried out in the rules of art. Transport Canada standards instruct users to follow manufacturers’ recommendations for the maintenance of their aircraft. As a general rule, maintenance should be performed every 200 hours or 6 months and by a certified center. In Canada, there are 2 main certifications for drone operations: basic operations and advanced operations.
Before any step, know that to be eligible for one of the two trainings you must meet these prerequisites :
– Be 14 years of age or older to take the Basic Operations Test
– Be 16 years of age or older to take the advanced operations exam
Each is governed by a different set of rules that must be followed. The weight of your drone, distance from passers-by and airspace rules define your category. The rules do not distinguish between drone pilots for recreational purposes and drone pilots for commercial purposes.
Comparison of different drones for surveying and surveyors.
Le Matrice 300
The Matrice 300 RTK from DJI is inspired by modern aviation systems. It offers an autonomy of up to 55 minutes of flight and its combination of on-board artificial intelligence and high performance make this drone a complete tool that provides very precise results.
The Matrice 300 RTK is designed with redundant systems and sensors to maximize flight safety and reliability. These redundancies and safety mechanisms include: dual sensors for the flight control system, dual links for control signals, dual smart batteries, dual transmission links, redundancies for the obstacle detection system and a three-prop emergency landing.
To enhance flight safety and device stability, dual-vision sensors appear on all six sides of the device, providing a maximum detection range of 40m, with options to customize the detection behavior of the device. device via the DJI Pilot app. Even in complex operational environments, this 6-direction sensing and positioning system helps keep the drone and the mission safe.
There are several combos for this drone, which allows you to have a more or less long warranty extension, or the possibility of having additional smart batteries and / or accessories. Find the comparison of all these combos, here.
Le Phantom 4 RTK ;
An RTK module is integrated directly into the Phantom 4 RTK, providing real-time, centimeter-accurate positioning data with unprecedented precision in image metadata. In addition to providing optimized flight safety and accurate data collection, the Phantom 4 RTK can also store satellite observation data to be used for post-processed kinematics (PPK).
In order to optimize the positioning modules of the Phantom 4 RTK, the new TimeSync system has been created to ensure perfect synchronization between the flight controller, the camera and the RTK module. In addition, TimeSync guarantees that each photo uses the most metadata. More accurate and places positioning data in the optical center of the lens, optimizing the results of photogrammetric methods and making it possible to obtain centimeter-accurate positioning data for your images.
Thanks to its camera, the Phantom 4 RTK is based on a 1-inch size sensor, which significantly improves the dynamic range compared to a smaller sensor, which translates into a much greater amount of detail, thus allowing to improve the quality and therefore ultimately the resolution/accuracy of the data.
Equipped with 20 megapixels, it is the perfect compromise between resolution and image size, this allows the creation of data sets of several hundred or even thousands of photos which will be processed fairly quickly by photogrammetry software.
In terms of FOV (opening of the field of vision of the camera), the camera and the optics of the Phantom 4 Pro have a wide enough opening to allow a good restitution of 3D environments which include verticalities and reliefs.
What are the techniques used for drone surveying?
Depending on the choice of data sensors and photogrammetric software, drone capture can produce various results with different use cases. These software solutions can assemble hundreds or thousands of digital photos captured by your drone and produce high quality orthomosaic maps, 3D models or contour lines.
An ortho-mosaic image is an aerial image taken by a drone, and by combining several ortho-mosaic images, an ortho-mosaic map can be created. This map gives a very detailed and undistorted result which improves the quality of the work.
The 3D models.
3D modeling is a three-dimensional reconstruction technique that is based on a true copy of the actual and not on a creation. However, the needs and the level of detail of the 3D modeling will be very different for a small object and a site of several hundred hectares. It is therefore in this sense that the drone is a particularly appreciated tool. It allows to acquire a lot of data in record time for limited costs.
The contour lines.
Aerial topography by drone makes it possible to produce orthophotos which make it possible to obtain precise three-dimensional maps with several contour lines in order to calculate surfaces or volumes in quarries for example.