Introduced in the 1960s, LiDAR technology originally measured large areas of terrain by mounting scanners to airplanes. Like Radar (Radio Detection and Ranging), this is achievable by emitting pulses toward the surface of the ground and bouncing them back to a sensor. Originally referred to as a "colidar system,” LiDAR sensors employ the same concept for measuring and creating 3D models today.
Original Source - FARO Technologies
The introduction of commercially viable GPS systems in the 1980s made LiDAR data useful for accurate geospatial measurements. Since then, research and development have rapidly advanced and improved LiDAR technology, making it commonplace for surveyors across the globe, via 3D laser scanning solutions like the FARO® Focus Premium™.
Lidar is an acronym for Light Detection and Ranging and is a remote sensing method for creating 3D models of the real world.
Depending on the LIDAR sensor, scanners can emit millions of laser pulses per second. Each pulse returns to the scanner, calculating the distance between the object and sensor using the velocity of light, referred to as the Time of Flight (ToF). The result is a single point in space and the combination of all these points creates a dense 3D visualization called point cloud data.
LiDAR and Radar both emit pulses to determine the time it takes to hit a surface and return to the sensor. Radar, however, uses radio waves instead of light pulses. LiDAR technology creates accurate measurements through 3D models, whereas the primary use for Radar is for military purposes i.e. on battleships to detect objects in the vicinity.
Lidar technology is an ideal way to examine the surface of the earth. Assessing information about the ground, creating a digital twin of an object, or detailing a range of geospatial information. Laser scanning solutions harness this technology, using LiDAR data to create 3D models and map digital elevation.
LiDAR maps give positional accuracy — both absolute and relative, to allow users of the data to know where in the world the mapping took place and how each point relates to objects in terms of distance.
There aren't many applications that wouldn't benefit from using LiDAR technology. From busy construction sites to deep underground — LiDAR sensors are ideal solutions for a variety of industries. Here are a few examples:
LiDAR technology is becoming increasingly prevalent in AEC. Tracking building projects and producing digital twins for Building Information Modeling (BIM). Plus mapping the built environment like buildings, road networks, or railways.
Surveying tasks often require laser scans to collect 3D measurements to create Digital Terrain Models (DTM) and Digital Elevation Models (DEMs) of landscapes and large areas.
Creating 2D floorplans using 3D point cloud data is ideal for measuring the space of a building or gaining insights ahead of renovation projects.
Environmental applications for LiDAR are plentiful. Laser scanning is a popular method of mapping flood risk, carbon stocks in forestry and monitoring coastal erosion.
Creating 3D models of mines provides greater visibility of progress but can also improve safety through various means like regularly reviewing and analyzing movement in the rockface.
LiDAR sensors are also implemented in autonomous vehicles (AVs), creating detailed 3D maps of the surrounding areas in real-time. LiDAR technology is key in providing AVs with the perception needed to navigate safely and efficiently in diverse environments.
Since the commercialization of Lidar technology, there have been various iterations of laser scanners.
The most common and longstanding use of a LiDAR sensor for mapping is in terrestrial laser scanners (TLS). A TLS is a static-based solution often on a tripod, emitting hundreds of thousands (in some cases millions) of light beams per second to create dense point cloud data.
TLS delivers highly accurate and granular data, which is ideal for applications like crime scene investigation or visualizing construction site progress.
The recent development of mobile laser scanners has opened opportunities for mapping previously hard-to-reach or impossible places. Though slightly less accurate than TLS, mobile LiDAR is significantly more versatile with the capacity for handheld, UAV, or vehicle-mounted scans. Additionally, SLAM-enabled systems do not require GPS to create a digital map, further widening its usability.
Solutions, like FARO® Orbis™, are ideal for industries like mining where speed, accuracy, and ease of capture are a must.
Apple was the first company to introduce Lidar to mobile phones and tablets in 2020. Though significantly less accurate than both mobile laser scanners and TLS, and lacking high levels of range, the development of the iPhone and iPad is a huge step towards getting LiDAR into more hands.
Working in tandem; TLS, mobile, and Lidar-enabled phones are the perfect solutions for consistent Lidar data capture of the same area over time.
A point cloud is a multitude (often millions) of points within the scans captured by a LiDAR scanner. These points represent a point on the surface of, for instance, a scanned building. The scanner combines the vertical and horizontal angles created by the laser beam to calculate a 3D XYZ coordinate position for each point to produce a set of 3D coordinate measurements.
Processing the data creates a point cloud dataset that gives an accurate detailed picture of the scanned environment. The denser the points, the more detailed the representation, which provides clarity for smaller features and texture details.
There are many great use cases for Lidar. These include civil engineering and surveying, from highways and roadworks to bridge inspection and mapping large retail developments. It is extensive, allowing surveying firms to be more cost-effective while maintaining the highest level of professionalism.
3D scanners help civil engineers get highly accurate results in a short space of time - essential when working with tight timeframes.
LiDAR technology is perfect for creating a digital model so you can spot and correct irregularities before building work starts, as well as monitor changes between scans to show progress.
Surveyors prefer LiDAR systems to help them create detailed 3D images, accurate digital terrain models (DTM), and digital elevation models (DEMs) of specific landscapes.
A Digital Elevation Model (DEM) is a three-dimensional representation of terrain and all the objects within that space. Regularly spaced elevation values collected from Lidar scans create a coordinate system that allows the earth to be reflected and modeled with a high level of accuracy.
Unlike DEM which considers objects like vegetation, buildings and other artifacts, a Digital Terrain Model (DTM) only considers the surface of the earth. A DTM will include heights and elevations of the surface, including ridges or rivers to give an accurate picture of the terrain.
Hopefully, we've satisfied your curiosity about Light Detection and Ranging. This pulsed laser technology has so many mapping applications, providing detailed information and data on the environment.
If you're looking for a 3D scanner for a business application, LiDAR technology gives you the power to collect the geospatial data you need. Our range of laser scanners produces point cloud data for many different applications and industries.