Roberts, B. H. | Search NASA

NASA NTRS1986

Star-Viewing Scheduler

Strategy and algorithm produce well-balanced timetable that accommodates many constraints. Strategy for scheduling star observations on Space Shuttle astronomy missions ensures best use of three future ultraviolet telescopes. Strategy, described in report, takes into account such diverse factors as maneuvers of Space Shuttle orbiter, interference by Moon, occultation by Earth, reflections, unstaffed periods during crew rotation, encounters with South Atlantic anomaly, and obscuration during dispersal of ejected water.

Guffin, O. T.↗

NASA NTRS1985

A practical scheduling algorithm for Shuttle-based astronomy missions

In the Astro mission series (initial flight planned for March, 1986), the Shuttle will be used as a dedicated stellar astronomy observatory. A modified Spacelab pallet is to be used for the Astro payload, which will consist of three ultraviolet (UV) telescopes and a wide field camera mounted together on a single gimbal mount called the Inertial Pointing System (IPS). Three flights of 7-10 days duration are to be made with the same payload at intervals of 8-9 months. Previous experience has shown that changes in design requirements are inevitable, and the evolution of operational concepts will effect changes in scheduling algorithm software. For these reasons, the design goals of the Astron algorithm and its family of auxiliary software modules have been related to functional modularity, constraint flexibility, user friendliness, and 'light' input requirements. Attention is given to hardware characteristics, environmental constraints, the basic criteria function, 'Cinderella' logic, counters and constraints, and scheduling trends.

Guffin, O. T.↗