An expert system for scheduling requests for communications links between TDRSS and ERBS

Abstract

This paper describes the ERBS-TDRSS Contact Planning System (ERBS-TDRSS CPS) that has been built to help Earth Radiation Budget Satellite (ERBS) flight operations personnel generate requests for service from the Tracking and Data Relay Satellite System (TDRSS). The ERBS-TDRSS CPS is written in the C language and runs on an IBM PC-AT. It uses a graphics interface and the Transportable Inference Engine (TIE-1) developed for NASA-(Goddard Space Flight Center) GSFC. First, ERBS-TDRSS Ground Track Orbit Prediction data are electronically transferred to the ERBS flight operations area, where, in its batch mode, the ERBS-TDRSS CPS automatically generates requests for TDRSS service (usually for one week). In this process, a series of scheduling strategies is used to generate requested events while TIE-1 determines whether each requested event is consistent with ERBS scheduling constraints. As requested events are rejected, alternative context-sensitive strategies are used to generate new requested events until a schedule is completed. In the interactive scheduling mode the ERBS planner can edit a schedule that has been previously built or choose which alternative scheduling strategies the ERBS-TDRSS CPS should use to build a schedule. Finally, a report generator builds “Schedule Requests” for each separate ERBS-TDRSS contact.