Powered Explicit Guidance Modifications and Enhancements for Space Launch System Block-1 and Block-1B Vehicles

Von der Porten, Paul ; Ahmad, Naeem ; Hawkins, Matt ; Fill, Thomas

关键词: ALGORITHMS;    GUIDANCE (MOTION);    NAVIGATION;    AUGMENTATION;    SPACECRAFT LAUNCHING;    JETTISONING;    SPACE LAUNCH SYSTEM (SLS);    DESIGN ANALYSIS;    LAUNCH VEHICLES;    BURNING TIME;    THRUST-WEIGHT RATIO;    MONTE CARLO METHOD;    ROBUSTNESS (MATHEMATICS);   

RP-ID  :  AAS Paper 18-136,M18-6485

学科分类：航空航天科学

美国|英语

来源: NASA Technical Reports Server

【 摘 要 】

NASA is currently building the Space Launch System (SLS) Block-1 launch vehicle for the Exploration Mission 1 (EM-1) test flight. NASA is also currently designing the next evolution of SLS, the Block-1B. The Block-1 and Block-1B vehicles will use the Powered Explicit Guidance (PEG) algorithm (of Space Shuttle heritage) for closed loop guidance. To accommodate vehicle capabilities and design for future evolutions of SLS, modifications were made to PEG for Block-1 to handle multi-phase burns, provide PEG updated propulsion information, and react to a core stage engine out. In addition, due to the relatively low thrust-to-weight ratio of the Exploration Upper Stage (EUS) and EUS carrying out Lunar Vicinity and Earth Escape missions, certain enhancements to the Block-1 PEG algorithm are needed to perform Block-1B missions to account for long burn arcs and target translunar and hyperbolic orbits. This paper describes the design and implementation of modifications to the Block-1 PEG algorithm as compared to Space Shuttle. Furthermore, this paper illustrates challenges posed by the Block-1B vehicle and the required PEG enhancements. These improvements make PEG capable for use on the SLS Block-1B vehicle as part of the Guidance, Navigation, and Control (GN&C) System.