Light detection and ranging (LIDAR)
Light Detection and Ranging, more commonly known as LiDAR, is a method of remote sensing that uses light in the form of a pulsed laser to measure distances to an 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.
Here's a simplified explanation of how it works:
- A LiDAR system sends out a pulse of light, usually in the form of a laser, and measures the amount of time it takes for the light to return after bouncing off objects (like the ground, trees, buildings, etc.).
- By multiplying this time by the speed of light, the system can calculate the distance to the object.
- If the system rapidly sends out many pulses of light in different directions, it can measure distances to many points in the environment.
- Combining all these distance measurements, the LiDAR system can build a detailed 3D model or "point cloud" of the environment.
LiDAR can be mounted on different platforms, such as satellites, aircraft, or ground vehicles. It's used in many applications, including topography, forestry, environmental research, and autonomous vehicles.
In the context of rescue robots, LiDAR can be used for navigation and for creating maps of the robot's surroundings. For example, a robot could use LiDAR to detect obstacles in its path, or to build a 3D model of a collapsed building in order to identify safe paths or locate people in need of rescue. It's particularly useful in low-light or smoky conditions, where traditional cameras might struggle.