Further potential applications of UAV remote sensing are geologic
hazard assessment of gas and oil pipelines [21]. Zhang and Elaksher
[22] presented a UAV-based imaging system for the 3D evaluation of
rural road surface distresses. For this purpose, a system consisting of
an inexpensive helicopter equipped with a camera for unpaved road
data acquisition, a global positioning system(GPS) receiver and an inertial
navigation system (INS) for navigating the helicopter were utilized.