REG NASA-LLIS-5201-2012 Lessons Learned - Consolidation of Requirements.pdf

1、Public Lessons Learned Entry: 5201 Lesson Info: Lesson Number: 5201 Submitting Organization: KSC Submitted by: Jenni Palmer Subject: Consolidation of Requirements Abstract: As the Constellation Program evolved, the allocation of requirements for ground processing subsystems became very cumbersome. B

2、ecause the allocation involved many tiers of responsible organizations, it created redundant work and made it difficult to trace requirements to their source. Description of Driving Event: Because allocating requirements for ground processing subsystems for the Constellation Program involved many ti

3、ers of responsibility and overseeing organizations, it was difficult to trace requirements to their source and to synchronize the updating of requirements at these multiple levels. For example, as the Constellation Program evolved, it was necessary to generate multiple levels of requirements from th

4、e System Requirements Documents (SRDs), Element Requirements Documents (ERDs), and Subsystem Requirements Documents (SSRDs). This created redundant work and made the requirements difficult to manage. Lesson(s) Learned: Much of the effort was not really involved in the functional decomposition of req

5、uirements but rather in how they were allocated, and this process could have been handled in a different way. In future programs, the decision about how to set up the levels of decomposition of the constituent components should be reviewed and fully vetted before any requirements are allocated downw

6、ard. By minimizing the levels of requirement decomposition, we can maintain the requirement database with fewer resources. Recommendation(s): Decompose requirements at the subsystem level and allocate them to the appropriate implementing organizations. Avoid creating unnecessary levels of responsibi

7、lity for the requirements. Evidence of Recurrence Control Effectiveness: N/A Documents Related to Lesson: N/A Mission Directorate(s): Exploration Systems Additional Key Phrase(s): Systems Engineering and Analysis. Systems Engineering and Analysis.Level II/III requirements definition Provided by IHSN

8、ot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Additional Info: Project: Constellation Approval Info: Approval Date: 2012-05-10 Approval Name: mbell Approval Organization: HQ Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-