Aerial photography for survey and mapping refers to the technology to make use of aerial camera or laser scanner on the plane or other aircrafts to obtain photos and point cloud of ground objects and to draw out topographic maps, combining measurement of ground control points, annotation and stereoscopic plotting. It is widely used in both ground mapping and many other fields such as building of national economy, military and scientific research.
In terms of market demands, recently, transitions in the demands for geographic information in survey and mapping have come up, including the transition from 2D geographic information to 3D geographic information, the transition from a lot of manual internal business processing to the use of efficient aerial survey systems and post-processing software and the transition from main ground surveying to the combination of ground, marine and aerial surveying. Besides, the market of unmanned aerial vehicles (UAVs) shows a continuous, powerful momentum, especially of consumer UAVs, agricultural plant protection UAVs and surveying UAVs.
From the point of view of technological innovation, key technologies, such as UAV flight control technology, multi-rotor UAV technology, high-resolution mapping camera and three-dimensional laser scanner, have been developed rapidly, well prepared for the rapid development of aerial photography.
A typical aerial photography system consists of aerial vehicles (UAVs mainly), three-dimensional laser scanner / oblique cameras, high-precision GNSS equipment, attitude reference device (IMU) and other parts. The laser scanner / oblique camera is a direct image and point-cloud collection device. The UAV is the carrier of the aerial photography system, which can provide a good position and angle for image shoot and point cloud scanning. The GNSS equipment provides location information to the carrier, facilitating data processing within the industry. IMU provides attitude reference for optical capture device, thus improving the accuracy of data processing on the one hand, and reducing the number of ground control points and increasing operating efficiency on the other hand.
Since aerial vehicles, especially UAVs, have strict requirements on the loaded equipment about their size and weight. INS100, a small and light integrated navigation system, used as an attitude reference system, is particularly suitable for aerial photography.