What is LiDAR System

If you’ve ever seen an autonomous vehicle, you may have noticed a rapidly-spinning tube mounted on its roof. This is a LiDAR system unit. Its role is to measure the distance of objects relative to the position of the car in 3-D. LiDAR system isn’t just used in self-driving cars.
LiDAR System Components
There are 4 main parts of an airborne LiDAR system. They work together to produce highly accurate:

LiDAR System Sensors:

As the self-control car travels, sensors scan the ground from side-to-side. The pulses are commonly in green or near-infrared bands.
GPS Receivers: GPS receivers track the altitude and location of the self-control car. These tracks are important for accurate terrain and elevation values.

InertiaL Measurement Units:

As self-control cars travel, LiDAR system use tilt to accurately measure the incident angle of the pulse.
Data Recorders: As the LiDAR system scans the surface, a computer records all of the pulse returns. Then, these recordings get translated into elevation.

How LiDAR System Works

First, a laser unit fires a short pulse of light. The pulse rebounds off a point, such as the rear of the car in front, and is detected by a sensor in the laser unit.
A computer connected to the unit measures the time between the initial pulse and the light return and, using the speed of light, calculates the distance the light has traveled.

How Do LiDAR System Sensors Work

Depending on the sensor used, LiDAR system scanning units can fire hundreds of thousands of pulses per second. These light waves bounce off objects and return to the LiDAR system sensor. The sensor uses the time it takes for each pulse to return to calculate the distance (time of flight). Each of these pulsed laser measurements, or returns, can be processed into a 3D visualization known as a ‘point cloud’. That’s how a LiDAR system sensor works explained in a nutshell. 

What is LiDAR System Technology?

LiDAR system technology is the application of the remote sensing method described above. It is usually used to examine the surface of the earth, assess information about the ground surface, create a digital twin of an object or detail a range of geospatial information. LiDAR system harness this technology, using LiDAR system data to map three-dimensional models and digital elevation. From handheld to airborne LiDAR system, there’s a LiDAR system to capture the data you need. LiDAR system mapping uses a laser scanning system with an integrated Inertial Measurement Unit (IMU) and GNSS receiver or in GeoSLAM’s case, the SLAM algorithm, which allows each measurement, or points in the resulting point cloud, to be georeferenced. Each ‘point’ combines to create a 3D representation of the target object or area. 
LiDAR system maps can be used to give positional accuracy – both absolute and relative, to allow viewers of the data to know where in the world the data was collected and how each point relates to objects terms of distance. 
LiDAR system data, in the form of a point cloud, can be used to map entire cities, enabling decision-makers to accurately pinpoint structures or areas of interest in millimeter-perfect detail. Features and objects such as road networks, bridges, street furniture, and vegetation can be classified and extracted. 
LiDAR system maps can also be used to highlight changes and abnormalities such as surface degradation, slope changes, and vegetation growth.