Light Detection and Ranging (LiDAR)

In News

• The Gujarat government is employing drone-based aerial Light Detection and Ranging (LiDAR) and photogrammetry technology.

About

• The technology will map with laser precision the exact contours, natural structures to buildings, including their cracks from the top precision.

LiDAR (Light Detection and Ranging) Technology

• LIDAR is a remote sensing method that uses light in the form of a pulsed laser to measure ranges (variable distances) to the Earth. 
• The light pulses along with other data generate accurate, high-resolution three-dimensional information of the object.
  • These light pulses, combined with other data recorded by the airborne system, generate precise, three-dimensional information about the shape of the Earth and its surface characteristics.

• A lidar instrument principally consists of a laser, a scanner, and a specialized GPS receiver. 
  • Aeroplanes and helicopters are the most commonly used platforms for acquiring lidar data over broad areas. 
• Types: Two types of lidar are topographic and bathymetric. 

• Topographic lidar typically uses a near-infrared laser to map the land, while bathymetric lidar uses water-penetrating green light to also measure seafloor and riverbed elevations.

Image Courtesy:elprocus.com

Uses

• This technology is used to map the land and is used to measure seafloor and riverbed elevations etc. 
• Aeroplanes and helicopters are the most commonly used platforms for acquiring lidar data over broad areas.
• It allows scientists and mapping professionals to examine both natural and manmade environments with accuracy, precision, and flexibility.
• Scientists are using lidar to produce more accurate shoreline maps, make digital elevation models for use in geographic information systems, assist in emergency response operations, and many other applications.
• The government is using LiDAR technology to provide fodder and water augmentation in forest areas so that animals will get food and water in forest areas and will not come outside.

Loopholes

• LiDAR can’t perform well in fog, rain, snow and dusty weather.
• Struggles to detect a glass wall or door, which is why smartphone manufacturers and self-driving cars makers use LiDAR along with secondary cameras and sensors.

Source: TOI