Algorithms and Preliminary Experiences With the LN93 and LN100 for Airborne Vector Gravimetry
Abstract
This report presents the results of investigations in using a medium-to-high accuracy inertial navigation system (INS) and a geodetic quality Global Positioning System (GPS) receiver on an airborne platform to determine the gravity disturbance vector along the trajectory of an aircraft. The main products of these investigations consist of derivations of alternative algorithms to estimate the horizontal gravity vector components given that the INS's under consideration have different types of available output data, either time-integrated accelerations and direction cosines or raw accelerometer and gyro data. In addition, two distinct data processing methodologies are elucidated to combine the GPS and INS data. The first is based on a traditional Kalman filter approach that treats the gravity disturbance vector as a stochastic process, and the second is an extension of the scalar airborne gravimetry concept. also, the configuration details of a loosely coupled INS/GPS system for airborne application are given, with particular emphasis on time synchronization. A limited number of field tests (ground and airborne) with the LN93 and LN100 were performed. Results from these tests verity the specified accuracy of the INS and yield initial attempted estimations of the vertical deflection using the Kalman filter approach. While the latter are inconclusive in assessing the precision level achievable with this method and instrumentation (due to unexpectedly poor gyro performance), they do indicate the feasibility of the approach provided the INS gyros perform at the specified level.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1998
- Accession Number
- ADA403482
Entities
People
- Christopher Jekeli
Organizations
- Ohio State University