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Mathematical model, program description and users guide to digital computer programs for interplanetary mission guidance and control
Digital computer program for performance analysis of all inertial guidance system along reference trajectories
IBM 7094 computer program for simulating atmospheric entry aided-inertial guidance systems
IBM 360/50 computer program for simulating low thrust aided-inertial navigation and guidance systems
Mathematical formulation of guidance equations and solutions for orbital space missions
Equations of relative motion and guidance for orbital transfer and docking maneuvers in spacecraft rendezvous
Iterative and perturbation approaches to near optimum steering equations for boost vehicle guidance
Methodology used in guidance system performance analysis /assessment/
Abort guidance system for Apollo lunar module
Launch vehicle guidance and control requirements for unmanned space missions - Vol. 2, Part 1
Design and tests of Lunar Orbiter guidance and control systems
Ground tracking capabilities as guidance sensors for spacecraft in lunar descent
Analytical models are presented for optimal trajectories and reentry guidance of the space shuttle orbiter. Major emphasis is placed on the development of a "footprint', which refers to a set of reachable destination positions attainable by the shuttle at a specified terminal altitude. An unconstrained reentry footprint was calculated for a shuttle vehicle which enters the earth's atmosphere at 93 km initial altitude after a deboost from a near earth orbit. The method of computation is briefly described, and graphs are presented which illustrate the footprint and the variation of state and control variables along it. The effects of constraints and of variations in initial state upon the footprint are discussed.
Erasable-memory programs (EMPs) designed for the guidance computers used in the command (CMC) and lunar modules (LGC) are described. CMC programs are designated COLOSSUS 3, and the associated EMPs are identified by a three-digit number beginning with 5. LGC programs are designated LUMINARY 1E, and the associated EMPs are identified, with one exception, by a three-digit number beginning with 1. The exception is EMP 99. The EMPs vary in complexity from a simple flagbit setting to a long and intricate logical structure. They all, however, cause the computer to behave in a way not intended in the original design of the programs; they accomplish this off-nominal behavior by some alteration of erasable memory to interface with existing fixed-memory programs to effect a desired result.
The history of a unique development program that produced an operational fixed guidance system of inertial quality is presented. Each phase of development, beginning with requirement definition and concluding with qualification and testing, is addressed, and developmental problems are emphasized. Software generation and mission operations are described, and specifications for the inertial reference unit are included, as are flight performance results. Significant program observations are noted.
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Computerized simulation of mission profiles for inertial navigation of low thrust spacecraft in both heliocentric transfer and planetocentric spiral