A Sensitivity Study into Strapdown Airborne Gravimetry

Airborne gravimetry is an important tool for the geodesy and geophysics communities. Able to provide medium to high-resolution measurements over large areas, it is the link between the low-resolution satellite measurements and expensive terrestrial campaigns, especially in remote areas. To explore the potential of airborne gravimetry, the Gravimetry using Airborne Inertial Navigation (GAIN) project was recently established at the faculty of Aerospace Engineering at TU-Delft, and is currently building and testing an in-house strapdown airborne gravimetry system with the objective of providing lowcost, high-accuracy gravity data for use in a wide range of applications in geodesy and geophysics. Within this thesis, the inertial sensors that will be used within the GAIN strapdown IMU are calibrated and modeled with a simulator to predict the accuracy of the airborne system when completed. A sensitivity study of several campaign parameters is done to understand which parts of the hardware and operating conditions are critical to the performance of the system. Of the list of applications for airborne gravity data, natural resource exploration is one of the more demanding in terms of accuracy and resolution, with a requirement of 0.5-2 mGal at 2 km resolution. This is beyond the range of current strapdown systems, so in addition to assessing the performance of the current strapdown system, additional tests were made to see what would be needed to achieve this higher level of accuracy. The simulation results suggest that the performance of the GAIN strapdown system, under ideal conditions, would be 1.4 mGal at 2 km resolution. Furthermore, the performance is limited by the accelerometers whose accuracy must improve by a factor of three before the 0.5 mGal level can be achieved; however, other options were identified that could also be used to achieve this. A Sensitivity Study into Strapdown Airborne Gravimetry