This decision support system provides an integrated platform for assessing the quality of Spitzer scheduling options. The application aids in scheduling instrument selection, assigns schedule times to specific observation requests, and generates stored sequence products destined for execution on the Spitzer Space Telescope.

SIRPASS is an adaptation of Plan-IT II, a JPL-developed spacecraft activity planning software application. The Plan-IT II software application has a long history of use at JPL, including the Mars Pathfinder and Galileo projects. Plan-IT II supports the modeling of spacecraft activities and their impacts on a variety of resources. Because this software architecture uses a highly object-oriented design, the core software can be easily extended for specific scheduling problem domains. Plan-IT II is developed in Allegro CL, a dynamic object-oriented development environment for ANSI Common Lisp. SIRPASS introduces a system of “extensions” to Plan-IT II for interfacing with the following systems: CSPICE, AMMOS, Emacs, Flat-File Reports, Gnuplot, HTML files, Models and Parameters, Reports, and Test Definitions. SIRPASS includes support for a complex set of observation constraints, data downlink models, database interfaces, and decision support tools.

SIRPASS is an improvement over other similar observatory scheduling software in that it is highly interactive without sacrificing the accuracy of its schedules. Care was taken to protect the end-user interface from being bogged down by a large volume of data needing manipulation. Processing of schedules is handled in successively more accurate steps in which the precise modeling and expansion of the commands associated with each observation are relegated to a non-interactive process that can take several hours to complete. A full complement of system-level models and activities is incorporated. The software includes activity type definitions for all of the approved Spitzer request types, models for each resource whose use impacts the schedule, and a variety of integrated models and interfaces that support the tasks and decisions required of the Observatory Planning and Scheduling Team.

This work was done by David S. Mittman, William C. Eggemeyer, and Tatiana Goldina of Caltech; and Larry Kramer and Robert Hawkins of Space Telescope Science Institute for NASA’s Jet Propulsion Laboratory.

This software is available for commercial licensing. Please contact Dan Broderick at This email address is being protected from spambots. You need JavaScript enabled to view it.. Refer to NPO-49093.


This Brief includes a Technical Support Package (TSP).
Spitzer Integrated Resource Planning and Scheduling System (SIRPASS)

(reference NPO49093) is currently available for download from the TSP library.

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This article first appeared in the October, 2015 issue of NASA Tech Briefs Magazine.

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