ABSTRACT
Remote sensing is the science, technology, and art of collecting information of an object or phenomenon without being in direct physical contact with it. Modern remote sensing for Earth observation has evolved from early photography techniques, which collected imagery using ornithopters, balloons, kites, pigeons, and gliders. Compared with satellite remote sensing, aerial acquisition offers the flexibility of being fitted with a wide range of sensors such as multispectral, hyperspectral/thermal, lidar and other survey sensors. Unmanned Aerial vehicles, also known as Unmanned Aerial Systems or simply drones, are an airborne remote sensing system or an aircraft operated remotely by a human operator or autonomously by an onboard computer. A lidar system has three major hardware components: a laser scanner sending laser signals, Global Positioning System measuring the location of the aircraft, and Inertial Navigation System measuring the pitch, roll, and yaw of the lidar system.
