1、Public Lessons Learned Entry: 5197 Lesson Info: Lesson Number: 5197 Submitting Organization: KSC Submitted by: Jenni Palmer Subject: Ground Systems Requirements Development Abstract: During the Constellation Program, each Ground Systems element generated its requirements independently. Differences i
2、n the terminology used by the different elements caused problems such as the inconsistent handling of interfaces between subsystems. Description of Driving Event: During the Constellation Program, each of the Ground Systems elements generated its own requirements independently, resulting in inconsis
3、tent practices for writing and allocating requirements. In addition, the language used in requirements documents was not consistent among subsystems, nor were the requirements flow schemas. Valuable time was spent trying to reconcile these discrepancies. The Mobile Launch Element generated its own r
4、equirements independently, using its own terminology. This resulted in inconsistent handling of interfaces between subsystems in regard to generating, providing, or receiving data and signals. The Command, Control and Communications Element did not have a single parent requirement for some of its ma
5、jor subsystems (i.e., multiple requirements were related to key pieces of subsystem functionality). Lesson(s) Learned: Because the engineers did not have a clear understanding of requirement derivation and flow schemas, requirement writing became a learning process rather than the systematic task it
6、 could have been. Recommendation(s): 1. Use a centralized Systems Engineering and Integration (SE&I) organization to establish standards for requirements development, including terminology and how interface requirements are worded. 2. Establish a training regimen for requirements development. 3. Hav
7、e SE&I participate in the approval process to ensure that the standards are followed. Evidence of Recurrence Control Effectiveness: N/A Documents Related to Lesson: N/A Mission Directorate(s): Exploration Systems Additional Key Phrase(s): Program Management. Program Management.Organizational Plannin
8、g Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Additional Info: Project: Constellation Approval Info: Approval Date: 2012-03-29 Approval Name: mbell Approval Organization: HQ Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
