From The Editor | August 9, 2023

LiDAR: Uncovering Ancient Cities And Roads, And Guiding Futuristic Robot Dogs

John Oncea

By John Oncea, Editor

Lidar GettyImages-1337105602

LiDAR can be used to map structures, improve self-driving cars, aid in disaster recovery, and a whole lot more. Let’s take a look at how it helped discover ancient cities and roads, as well as how it is helping develop robotic dogs.

LiDAR. Is there anything it can’t do?

A remote sensing technology used to measure distances by illuminating a target with laser light and analyzing the reflected light, LiDAR is commonly used for creating high-resolution 3D maps and various applications in self-driving vehicles. But this technology has expanded beyond its traditional applications and is being used in unique and innovative ways:

  • Archaeology and Cultural Heritage Documentation: LiDAR is employed to create highly accurate and detailed 3D models of archaeological sites, cultural heritage sites, and historical buildings. This technology aids in preserving and documenting these sites while also uncovering hidden features that might not be visible through traditional methods.
  • Precision Agriculture: LiDAR-equipped drones or aircraft are used to create detailed topographical maps of farmland. These maps help farmers optimize irrigation, planting, and fertilization by identifying areas with varying elevations and drainage patterns.
  • Forestry Management: LiDAR is used for forest inventory and management. It provides data on tree height, density, and structure, helping forest managers make informed decisions about harvesting and conservation efforts.
  • Environmental Monitoring: LiDAR can be used to monitor and assess natural environments, such as tracking changes in vegetation, mapping wetland areas, and monitoring coastal erosion and land cover changes.
  • Disaster Response and Recovery: LiDAR-equipped drones can quickly survey disaster-stricken areas, such as earthquake or landslide sites, to assess damage, identify hazards, and plan rescue and recovery efforts.
  • Virtual Reality and Gaming: LiDAR data is increasingly used in virtual reality (VR) and gaming applications to create realistic and immersive environments. This technology enhances the visual quality of games and simulations by providing accurate 3D representations of objects and spaces.
  • Architectural and Structural Design: LiDAR is used in the architectural and construction industries to create precise 3D models of existing buildings and sites. This aids in renovation, retrofitting, and designing structures that need to fit into existing environments.
  • Geomorphology and Geology: LiDAR is used in geological studies to analyze landforms, identify fault lines, and study changes in terrain over time. This technology provides valuable insights into Earth's natural processes and history.
  • Wildlife Conservation: LiDAR is used to monitor and study wildlife populations, including tracking animal movement patterns, estimating population densities, and assessing habitat suitability.
  • Urban Planning: LiDAR data helps urban planners visualize and analyze urban environments, including infrastructure planning, transportation networks, and land use.
  • Underwater Mapping: LiDAR technology has been adapted for underwater mapping, allowing researchers to create detailed 3D maps of underwater landscapes, shipwrecks, and coral reefs.
  • Industrial Inspection: LiDAR is used for inspecting large industrial structures, such as bridges, towers, and pipelines. It can identify deformities and structural weaknesses more efficiently than traditional inspection methods.

The Science Behind LiDAR

LiDAR is a system that detects objects by bouncing light off them, Analog Devices reports. The system has a transmitting part that emits light and a receiving part that measures the time it takes for the reflected light to return. This is similar to traditional radar systems but with one crucial difference – LiDAR systems have a much shorter wavelength than radar systems, almost ten thousand times shorter.

“A shorter wavelength allows us to see a much higher resolution image, due to a physical limitation that a measurement cannot be more precise than what is used to measure it,” writes Analog Devices. “Even with tricks in software and signal processing, you can only characterize something so well if you are using long wavelengths to do it. With LIDAR’s shorter wavelength, we can scan the environment for objects and their features, instead of being limited to only knowing location, rough size, and velocity.”

LiDAR technology has found significant use in autonomous vehicles, where it helps vehicles perceive and understand their surroundings, enabling safe navigation and obstacle avoidance. It is also used in terrain modeling, floodplain mapping, coastal erosion monitoring, and archaeological site documentation, among other applications.

However, it's important to note that LiDAR systems can be relatively expensive and require careful calibration and processing to generate accurate and meaningful data. In recent years, there have been advancements in LiDAR technology, leading to smaller, more cost-effective sensors that are being integrated into a broader range of applications.

LiDAR In Action

With a basic understanding of what LiDAR is let’s take a look at three specific ways LiDAR is being used, starting with the discovery of a 650-square-mile Maya site hidden that geologists discovered in northern Guatemala.

According to Live Science, “The findings were the result of an aerial survey that researchers conducted via airplane using LiDAR, in which lasers are beamed out and the reflected light is used to create aerial imagery of a landscape. The technology is particularly beneficial in areas such as the rainforests of Guatemala's Mirador-Calakmul Karst Basin, where lasers can penetrate the thick tree canopy.

Based on scan data, the team discovered over 1,000 settlements scattered throughout the area. These settlements were connected by 100 miles (160 kilometers) of causeways that the Maya probably walked on. Furthermore, they found the remains of various large platforms and pyramids, as well as canals and reservoirs used for water collection

LiDAR has been utilized by researchers in Guatemala since The Mirador Basin Project, launched in 2015, carried out two extensive surveys of the southern section of the basin, with a focus on the historic city of El Mirador. The outcome of this project was the mapping of 658 square miles (1,703 square km) of this area of the country, as stated in the study.

"When I generated the first bare-earth models of the ancient city of El Mirador, I was blown away," Morales-Aguilar said. "It was fascinating to observe for the first time the large number of reservoirs, monumental pyramids, terraces, residential areas, and small mounds."

More recently, University of Exeter archaeologists using laser scans collected as part of the Environment Agency’s National LiDAR Programme uncovered a Roman road network spanning the southwest U.K., according to Phys.org. “Using sophisticated geographical modeling techniques, which incorporate information around gradients and flood risk, the researchers have then been able to map out the full extent of the network and begin to understand the rationale for its existence,” writes Phys.org.

“Despite more than 70 years of scholarship, published maps of the Roman road network in southern Britain have remained largely unchanged and all are consistent in showing that west of Exeter, Roman Isca, there was little solid evidence for a system of long-distance roads,” Dr. Christopher Smart said. “But the recent availability of seamless LiDAR coverage for Britain has provided the means to transform our understanding of the Roman road network that developed within the province, and nowhere more so than in the far southwestern counties, in the territory of the Dumnonii.”

Between 2016 and 2022, the Environment Agency conducted the National LiDAR Programme in England, greatly increasing the amount of terrain mapped in Devon and Cornwall which previously stood at a low 11%. With the assistance of public volunteers, the Exeter team analyzed the scans and successfully mapped an additional 100km of roads.

Finally, do you want one of Boston Dynamics’ robot dogs but don’t have an extra $75,000? Welp, now you can snag one from Unitree for $2,400 after shipping and duty fees.

According to Ars Technica, the Chinese robotics company's stripped-down consumer version “stands at just under 16 inches tall, is 27 inches from head to tail, and weighs 33 pounds. It has a camera, flashlight, and a constantly spinning 360-degree LiDAR sensor on the face.

“The robot has 12 motors — we're guessing that means three for each leg — making this a pretty agile robot able to deal with all sorts of uneven outdoor terrain and, like any good dog, do a ton of tricks. The Go2 has an 8000 mAh battery good for about “1–2” hours of runtime, along with Wi-Fi 6 and Bluetooth for communication with the app. The base model has a top speed of 2.5 meters per second.”

Ars Technica notes there is also a $2,800 Pro model available that comes with “a speaker and microphone combo for voice commands, media playback, and intercom functions. There's a ‘Wireless Vector Positioning Tracking Module’ for following commands, 4G connectivity, a faster CPU, and a higher 3.5 m/s top speed.”