{"683696":{"#nid":"683696","#data":{"type":"event","title":"PhD Defense by Jonathan Schiller","body":[{"value":"\u003Cp\u003E\u003Cstrong\u003EJonathan Schiller\u003C\/strong\u003E\u003Cbr\u003E\u003Cem\u003E(Advisor: Prof. Christian)\u003C\/em\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cem\u003Ewill defend a doctoral thesis entitled,\u003C\/em\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ERange and Range Rate Beacon Based Initial Orbit Determination for Cislunar and Interplanetary Applications\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cem\u003EOn\u003C\/em\u003E\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ETuesday, August 19 at 2:00 P.M.\u0026nbsp;\u003C\/strong\u003E\u003Cbr\u003E\u003Cstrong\u003ECODA Building Room C1015 Vinings\u003C\/strong\u003E\u003Cbr\u003E\u003Cbr\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EAbstract\u003C\/strong\u003E\u003Cbr\u003EMost spacecraft rely on some form of navigation architecture to provide them with information on their orbital state.\u0026nbsp; Close to the Earth, they can rely on Global Navigation Satellite Services (GNSS) or ground-based tracking networks to determine their orbits.\u0026nbsp; Farther from the Earth, options become more limited, with many relying on the overburdened Deep Space Network (DSN) or turning to more autonomous methods of navigation.\u0026nbsp; Recent proposals have suggested deploying a navigation constellation similar to GNSS at the Moon, but this comes at great cost and still leaves many regions of space without coverage.\u0026nbsp; This work provides theoretical frameworks to extend beacon-based navigation to new areas of space while keeping costs down.\u0026nbsp; As keeping track of precise orbits can be done using batch and Kalman filtering techniques, this work focuses on the more difficult problem of initial orbit determination (IOD) over a period of time using fewer than four beacons simultaneously.\u0026nbsp; Three IOD algorithms are developed, all using range and range rate measurements derived from navigation beacons.\u0026nbsp; First, an optimization-based algorithm using two beacons is presented for use with either the restricted two body problem or the circular restricted three body problem (CR3BP).\u0026nbsp; Next, a root-finding-based algorithm using two beacons is shown which is more efficient than the first algorithm for the two body problem but does not work for the three body problem.\u0026nbsp; Finally, another optimization-based algorithm is developed using a single beacon for use exclusively in the CR3BP.\u0026nbsp; These three algorithms together can enable IOD for use in low-cost navigation architectures for cislunar and interplanetary applications.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003ECommittee\u003C\/strong\u003E\u003C\/p\u003E\u003Cul\u003E\u003Cli\u003EProf. John A. Christian \u2013 School of Aerospace Engineering (advisor)\u003C\/li\u003E\u003Cli\u003EProf. Koki Ho \u2013 School of Aerospace Engineering\u003C\/li\u003E\u003Cli\u003EProf. E. Glenn Lightsey \u2013 School of Aerospace Engineering\u003C\/li\u003E\u003Cli\u003EProf. Thomas Gonz\u00e1lez Roberts \u2013 School of Aerospace Engineering\u003C\/li\u003E\u003Cli\u003EDr. Gregory Badura \u2013 Georgia Tech Research Institute\u003C\/li\u003E\u003C\/ul\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E","summary":"","format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003E\u003Cstrong\u003ERange and Range Rate Beacon Based Initial Orbit Determination for Cislunar and Interplanetary Applications\u003C\/strong\u003E\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Range and Range Rate Beacon Based Initial Orbit Determination for Cislunar and Interplanetary Applications"}],"uid":"27707","created_gmt":"2025-08-11 11:44:01","changed_gmt":"2025-08-11 11:44:39","author":"Tatianna Richardson","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2025-08-19T14:00:00-04:00","event_time_end":"2025-08-19T16:00:00-04:00","event_time_end_last":"2025-08-19T16:00:00-04:00","gmt_time_start":"2025-08-19 18:00:00","gmt_time_end":"2025-08-19 20:00:00","gmt_time_end_last":"2025-08-19 20:00:00","rrule":null,"timezone":"America\/New_York"},"location":"CODA Building Room C1015 Vinings","extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[{"id":"100811","name":"Phd Defense"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78771","name":"Public"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}