There are two main categories of Lidar. The first one is the airborne type and the second one is the terrestrial type.
These two main categories are then divided into 4 subcategories. They each have their own functionalities to answer all kinds of needs.
The airborne type is a laser scanning system that is attached to an airplane, helicopter or drone. Light pulses are sent to the ground and measure the distances and the dimensions of the landscape that is below.
What are the advantages of the Airborne Lidar?
– It is easy to scan large areas, without limitation of time since as long as the plane or the device is running, it is possible to collect data.
– It saves you time and budget since you can cover more area in a shorter period of time compared to terrestrial Lidar.
– Compared to terrestrial Lidar, Airborne Lidar doesn’t have to avoid obstacles on the ground like trees, power lines, etc.
Types of airborne Lidar
There are two types of airborne Lidar. They both work in the same way, but they each have their own functionalities.
This kind of Lidar usually maps the land using near-infrared light. The data that is collected from topographic Lidar can create topographic maps of the scanned area. It is mainly used for urban planning projects.
Bathymetric Lidar is much more suited for scanning through water. It uses a water-penetrating green laser and an infrared light to measure seafloor and riverbed elevations. It can be used to gather information about land and sea even though it is more used on coastal projects.
Terrestrial Lidar is fixed to a stationary device or a tripod on the ground.
This system often scans in several directions with the use of mirrors instead of scanning down. This allows the system to capture data all around. It is used to develop point cloud for mining, archaeology, etc.
Advantages of Terrestrial Lidar
– Terrestrial Lidar can work with an airborne system to give more information about an object and to have a more detailed look of a specific object
– It is used in areas that airborne Lidar can’t reach
Types of Terrestrial Lidar
Mobile Lidar systems are attached to moving vehicles like cars, trains, and boats. It is a good option for scanning roads and railroads and it can scan their conditions, signs and power lines. Mobile Lidar is often used for 3D mapping because it collects a denser database of points (coordinates). That creates more detailed 3D images and maps.
That kind of Lidar is the only one that isn’t moving. It is attached to a
non-moving tripod and it is used to scan the entire surrounding area or to focus on a specific one. It can scan in all directions possible, including upwards. That tripod can be moved to a different location once the scan is over to ensure a comprehensive coverage of the area. Static Lidar is used for scanning building interiors or to scan specific outside areas. It is very popular and used by engineers, architects, archeologists and mining projects.