Small unmanned aerial vehicle (UAV) sensor platforms like a
multicopter develop to important auxiliary tools in the scope of close range remote
sensing. They provide new opportunities of data acquisition for various
environmental- and geoscientific purposes. One of the objectives of the ifgicopter
project is to produce CIR images as classified input data for subsequent procedures
of precision farming. Therefore, the projects’ multicopter is equipped with a
modified digital camera to record high resolution aerial CIR images. In a
subsequent step, the captured images are processed to orthophotographs. Focal
distortions are eliminated and the positions of the images are calculated relative to
a desired frame of reference. This processing usually requires a certain amount of
known Ground Control Points (GCP) to acquire information about the parameters
of exterior orientation of the images. The measurement of these points is costintensive and time-consuming. For this reason the ifgicopter navigation system is
extended with DGPS-devices in order to determine the essential parameters of the
exterior orientation without the need of GCP’s. Moreover, sensor data from onboard sensors such as gyroscopes, accelerometers and a magnetometer is
combined to an inertial navigation system (INS) and coupled to the GPS position
solutions. Therefore trajectory and orientation of the multicopter and its camera
system are tracked at each point in time. The now available information allows the
calculation of CIR orthophotographs as part of a sensor web-enabled service for
subsequent procedures of precision farming.