LiDAR, the term composed out of words light and radar, is a measuring method whose mapping technology is based on remote sensing. It stands for light detection and ranging measuring method used to determine the range between the system and the targeted object. It is often referred to as an active laser scanning as it uses strobing laser light to scan and map surfaces.
Not only does it provides measurements, but it can provide a pretty accurate 3D imaging of the Earth’s surface. But there is more to LiDAR than that. So, dig a little deeper into the origin of this technology, its principles, and practical application. If you are feeling like learning more about it, what it is, and how it works, you will find tons of information about it here.
Origin Story
The first-ever LiDAR technology was introduced in 1961 and its main intention was to track satellites. Back then, the idea behind the whole system was to measure the distance by calculating the traveling time of the signal. This sort of light detecting and ranging technology was perfected and upgraded from then on.
Two years later, a laser rangefinder system with practical terrestrial applications appeared. It surely wasn’t as precise as the current LiDAR, however, it was used to measure wavelengths from distant objects. All of this happened during the same year, and it marked incredible progress in this field.
Let us not forget to mention that this technology became widely known after the mapping of the moon surface during Apollo 15. Among its first practical applications was equipping airplanes with a laser scanner, but it wasn’t until the 80s that it found its use in geovisualization and spatial statistics as well as meteorology. During those times, the system was mainly used to measure pollution.
LiDAR Technology
When we are talking about LiDAR technology we need to understand that it is a system that uses GPS, laser light, and IMU. To understand this type of technology, one must know what are its basic parts: laser, scanner, photodetector, optics, and a GPS receiver. All of the mentioned parts gather information crucial to creating the most accurate measurements.
As mentioned before, LiDAR is a measuring method based on laser and reflection via a sensor. By casting light onto the wanted target, it is able to measure the target’s distance from the earth. All of this is possible by gathering information and producing a precise 3D image via the pulsed laser and other data.
Breaking it Down
This technology uses visible, ultraviolet, or near-infrared light to scan the target. As far as the material is concerned, it can scan and map out different objects (non-metal), chemicals, water, aerosols, molecules, etc. Talking about the precision and resolution, such systems are able to provide HD mapping.
The primary role of this technology was to research the atmosphere, and indeed, this is one of the fields LiDAR is still used for. In addition, some of the most recent considered uses are the ones by NASA, and they include a precise and safe landing of robotic moon vehicles. And not only that, but also safe landings of vehicles maneuvered by real people.
LiDAR wavelengths can be different, depending on the targeted area or object. These can go from 10 μm to 250 nm. To point out, the reflection of the laser light is not as pure as it would be with surfaces such as a mirror. The reflection is more backscattered and these can vary depending on the application.
Where Can It Be Applied?
LiDAR technology can be used in terrain models in infrastructure development. For example, it could be useful when building highways, roads, buildings, etc. It can also provide fundamental data in various geoscience fields. Another great way to use LiDAR is in oceanography, measuring how deep some parts of seas and oceans. Apart from the above-mentioned study field, LiDAR can be used in agriculture, geoscience, archaeology, and many more life fields.
It can also be used in video game development, in games such as simulation racing games. For example, games like Project CARS or iRacing are using 3D racetrack models gathered with the help of LiDAR. This way, some areas, and surfaces can be simulated and designed with millimeter exactness. Using that sort of game mechanics is becoming more and more popular in recent years.
Besides, this kind of technology is crucial for the future of companies such as Drover. Even if we are still far from split rideshare in an autonomous vehicle, implementing LiDAR seems like it could offer many rideshare options. And not only that! It could be used for calculating rideshare fare estimate according to the distance, while you are riding in Chevy economy cars.
LiDAR Mapping
LiDAR systems are composed of a laser scanning system with IMU (Inertial Measurement Unit) and GNSS. All of this helps the system make a measurement, determine a point in a point cloud, and create a 3D representation of an area or target. Creating such a map provides spatial preciseness and it allows users to learn where the information has been gathered.
So, what can it map? LiDAR mapping can serve to map urban areas such as cities and facilitate further infrastructural development. This way, decision making, and planning are precise and perfected. Besides, it can be used to map out different surface changes or vegetation transformation and growth in order to spot threatening abnormalities in time.
The Principle Behind LiDAR
The principle behind the technology is quite simple - laser light is cast on an object and the traveling time of the laser light from the LiDAR source, to the targeted object and back to the source will help determine the distance. So, how is the distance measured? Having in mind the speed of light, and the laser light traveling data, it is possible to get quite precise measurements.
Types of LiDAR
This technology applicable in many fields today can be divided into two main types. One is airborne and the other one is terrestrial. The first one is usually added to a plane, helicopter, or drone from where the data is gathered. This type also has two subtypes and those are bathymetric and topological LiDAR. The second one, or the terrestrial LiDAR, are attached to vehicles or other objects from where the data will be gathered. Terrestrial LiDAR has two subtypes - static and mobile.
