The Evolution of Seqgen - A Spacecraft Sequence Simulator

Abstract

Spacecraft continue to become more complex and more capable as computer processors have become significantly smaller as well as providing more processing capability, more memory and higher performance. Mission operations must still make sure that the spacecraft executes its commands safely and efficiently. At Jet Propulsion Laboratory almost all of the mission operations teams use a multi-mission software tool called SeqgenSequence Generator. Seqgen is a discrete event simulator that models the effects of spacecraft commands. Initially Seqgen simply checked and modeled an absolute timeordered list of spacecraft commands. That Seqgen existed twenty years ago and the tool can still operate in that mode. However, now Seqgen has evolved and performs many more functions including event driven modeling. This paper will discuss the evolution of Seqgen from it initial simulation capabilities to a much more complex variation.

Revolutionizing space mission event modeling with the Tychonis framework

“…Command validation entails the use of tools to model the low-level behavior of the spacecraft. This task is commonly accomplished through the implementation of simulators [10] that integrate models or the utilization of the flight software [11] itself on either a testbed or an end-user workstation. However, both of these options entail significant costs for implementation and maintenance.…”