Encke-Beta Predictor for Orion Burn Targeting and GuidanceThe state vector prediction algorithm selected for Orion on-board targeting and guidance is known as the Encke-Beta method. Encke-Beta uses a universal anomaly (beta) as the independent variable, valid for circular, elliptical, parabolic, and hyperbolic orbits. The variable, related to the change in eccentric anomaly, results in integration steps that cover smaller arcs of the trajectory at or near perigee, when velocity is higher. Some burns in the EM-1 and EM-2 mission plans are much longer than burns executed with the Apollo and Space Shuttle vehicles. Burn length, as well as hyperbolic trajectories, has driven the use of the Encke-Beta numerical predictor by the predictor/corrector guidance algorithm in place of legacy analytic thrust and gravity integrals.
Document ID
20160001446
Acquisition Source
Johnson Space Center
Document Type
Conference Paper
Authors
Robinson, Shane (NASA Johnson Space Center Houston, TX, United States)
Scarritt, Sara (NASA Johnson Space Center Houston, TX, United States)
Goodman, John L. (Odyssey Space Research, LLC Houston, TX, United States)
Date Acquired
February 3, 2016
Publication Date
February 5, 2016
Subject Category
Lunar And Planetary Science And ExplorationAstrodynamics
Report/Patent Number
AAS 16-112JSC-CN-35068
Meeting Information
Meeting: Annual AAS Guidance and Control Conference