Light Detection and Ranging (LiDAR) systems technology has revolutionized remote sensing, surveying, and monitoring in recent years. This cutting-edge technology has found applications across various industries, such as forestry, disaster management, weather prediction, construction, archaeology, and autonomous vehicles, to name a few.
However, it’s essential to understand that LiDAR isn’t a one-size-fits-all technology; various types are suited to specific applications and functionalities. In this piece, we’ll delve into the different typest
LiDAR systems can be initially categorized based on their functionality and setup.
Terrestrial
Terrestrial LiDAR operates on the ground level and can be vehicle-mounted or installed at a fixed location. The granular ground-level data it provides makes it ideal for applications requiring detailed surveys or close examination of objects. Some application areas include construction, autonomous vehicles, city and road surveys, and more. This type of LiDAR is further subdivided into mobile and static versions.
Mobile: Mobile LiDAR is typically equipped with a sensor, a Global Positioning System (GPS), an Inertial Navigation System (INS), and cameras. Installed on a moving vehicle, it emits laser pulses in all directions and captures the reflections to create detailed datasets (point clouds). The data is then analyzed for various purposes, like studying road conditions or detecting obstacles. Autonomous vehicles, for example, use advanced rotating LiDAR sensors to detect pedestrians and other vehicles.
Static: Certain applications benefit from a stationary LiDAR unit, and that’s where static LiDAR comes into play. Though immobile, these systems mounted on tripods are portable and can be relocated as needed. The fixed laser pulses it sends aid in understanding the surroundings’ characteristics, making it especially useful in construction, mining, and engineering industries.
Airborne
Airborne LiDAR, as the name implies, is operated from aircraft or helicopters, offering a broader perspective by scanning large areas. This system can be broken down further into topographic and bathymetric LiDAR.
Topographic: This type of LiDAR is employed to scan and estimate various land characteristics. It creates detailed topographic maps by measuring the rise and fall of the surface based on reflected laser beams’ altitudes. It’s typically used in forestry, urban planning, ecology, infrastructure mapping, geomorphology, and more.
Bathymetric: Bathymetric LiDAR is specially designed to survey bodies of water. Alongside the standard components, it can emit green laser pulses, penetrating the water’s surface and bouncing back to the aircraft, providing depth estimates. Coastal engineering and marine sciences predominantly use this LiDAR system.
Satellite
Satellite LiDAR systems, housed in earth-orbiting satellites, can scan vast terrestrial and atmospheric portions. Organizations like NASA have employed such space-borne systems to study cloud formations, vegetation patterns, polar ice conditions, and atmospheric particles.
Types of LiDAR Systems by Application
Beyond functional categorization, LiDAR systems can also be classified according to specific application requirements.
Differential Absorption LiDAR (DIAL)
DIAL is used to monitor atmospheric gas concentrations, specifically ozone levels. These systems can operate on land or in the air and measure pollution levels. They use a tunable laser to generate two laser pulse wavelengths that record data from a gas absorption peak and a low-absorption region.
Wind
Wind LiDAR is engineered to measure wind movement, a task notoriously tricky for traditional remote sensing equipment due to the wind’s rapidly changing nature. Advanced systems with 360-degree wind monitoring can provide invaluable insights into turbulences, wind speed, and direction.
Raman
Raman LiDAR, a terrestrial system, is designed to detect and measure the environment’s water vapor and aerosol levels. Unlike conventional LiDAR units, it can detect signals in backscattering at different wavelengths due to inelastic scattering, providing a highly accurate estimation of aerosol presence.
HSRL
High Spectral Resolution LiDAR (HSRL), an airborne system, determines aerosols’ presence in the atmosphere using the spectral distribution of reflected LiDAR signals. It differentiates between pulses reflected by molecules and those sent back by aerosols.
The broad spectrum of LiDAR types allows users to choose the best system for their needs. These systems cater to various functionalities and applications, from mobile to static and terrestrial to airborne. As technologies like differential absorption and inelastic scattering continue to advance, the potential use cases for LiDAR are only set to expand.
Additionally, companies like Inertial Labs are further pushing the boundaries of LiDAR technology. With their innovative and robust solutions, ranging from terrestrial LiDAR systems perfect for land surveying to advanced airborne setups for large-scale mapping, the potential applications of LiDAR continue to grow. Inertial Labs’ solutions also demonstrate a keen focus on developing LiDAR technology that is efficient and more accessible to users across various industries.
In essence, the world of LiDAR is diverse and ever-evolving, making it a vital player in many industries today and undoubtedly in the future.