High precision pointing system for airborne sensors

The Position and Orientation System for Direct Georeferencing (POS/DG) is an off-the-shelf integrated GPS/inertial system designed specifically for airborne applications. It performs high quality measurements of position and orientation of an airborne sensor. Using an Inertial Measurement Unit (IMU) as the primary sensor, POS/DG achieves measurement accuracies of about 10 to 20 cm (RMS) in position and 20 to 30 are seconds (RMS) in attitude. POS/DG is used with airborne sensors requiring high-accuracy attitude measurements such as aerial cameras, multispectral scanners, laser scanners and digital cameras. For aerial cameras, POS/DG´s performance enables the direct georeferencing of aerial photos to about 20 microns without aerial triangulation and ground control. The elimination of the aerotriangulation process translates to large savings in post-processing, data turn-around and flying time. The application of POS/DG to airborne photogrammetry is discussed and flight test results are presented