Gravity Gradiometry and Map Matching

<p>Inertial navigation systems (INS) offer passive all-weather and undeniable navigation information which military customers often view as especially appealing strengths. Unfortunately Airmen and engineers still struggle with INS's drifting position errors and navigation aids generally detract from INS's strengths. At this year's Air Space and Cyberspace in the 21st Century Conference the Chief of Staff of the Air Force identified the Global Positioning System (GPS) as a widely-known and exploitable vulnerability saying that it's critical the Joint force reduce GPS dependence. Recent advances provide an opportunity for gravity gradient instruments (GGI) which measure spatial derivatives of the gravity vector to aid an INS and preserve its strengths. This thesis shows that a GGI and map matching enhanced (GAME) INS improves navigation accuracy presents the conditions that make GAME feasible for aircraft and identifies opportunities for improvement. The methodology includes computer models and algorithms where a GGI and map matching aid an INS through a Kalman filter. Simulations cover different terrains altitudes velocities flight durations INS drifts update rates components of the gravity gradient tensor GGI and map noise levels map resolutions and levels of interpolation. Although GAME with today's technology only appears worthwhile for long range and long endurance flights the technologies expected in 10 years promise a broad spectrum of scenarios where GAME potentially provides great returns on investments and dominates the market for secure and covert navigation.</p><p>This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact and remains as true to the original work as possible. Therefore you will see the original copyright references library stamps (as most of these works have been housed in our most important libraries around the world) and other notations in the work.</p><p>This work is in the public domain in the United States of America and possibly other nations. Within the United States you may freely copy and distribute this work as no entity (individual or corporate) has a copyright on the body of the work.</p><p>As a reproduction of a historical artifact this work may contain missing or blurred pages poor pictures errant marks etc. Scholars believe and we concur that this work is important enough to be preserved reproduced and made generally available to the public. We appreciate your support of the preservation process and thank you for being an important part of keeping this knowledge alive and relevant.</p><br>