1、Lessons Learned Entry: 2476Lessons Learned Entry: 2476Lesson Info:a71 Lesson Number: 2476a71 Lesson Date: 2010-03-23a71 Submitting Organization: JPLa71 Submitted by: David Oberhettingera71 POC Name: Joy Bottenfield; P.J. Guskea71 POC Email: Joy.A.Bottenfieldjpl.nasa.gov; Patrick.J.Guskejpl.nasa.gova
2、71 POC Phone: 818-393-1144 (Bottenfield); 818-354-4950 (Guske)Subject: Place Flight Scripts Under Configuration Management Prior to ORT Abstract: When flight scripts developed independently by project personnel are not placed under configuration control early enough in flight software development, m
3、ultiple versions of the scripts tend to proliferate and cause confusion and delays. The MER, Juno, and GRAIL projects demonstrated the utility of placing flight scripts under change control prior to ORT.Description of Driving Event: Flight scripts are modules of software code used to automate many f
4、light software development and test processes that were previously done manually and repetitively. Because flight scripts are considered to be “development support“ software (Class D), they are not placed under configuration management (CM) control as early as mission software classified as Class C
5、(Mission Support) or Class B (Mission-Critical). This timing may be appropriate because instituting Mission System Change Control Board (MCCB) control of the scripts too early may impede the flight system development process, but very late initiation of formal control may result in excessive softwar
6、e iterations and may compromise test-as-you-fly fidelity or test procedure accuracy. The solution proven on several recent spaceflight projects is to institute change management of flight scripts prior to Operational Readiness Test (ORT). The Orbiting Carbon Observatory (OCO) project found that the
7、process of flight script development continued for too long (Reference (1). Given the multiple script authors and the potential impact of changes, the Flight Operations Team should have been in control of the scripts prior to the start of mission rehearsals (i.e., ORT). Provided by IHSNot for Resale
8、No reproduction or networking permitted without license from IHS-,-,-Lessons Learned Entry: 2476The Mars Exploration Rover (MER) project should have placed more emphasis on management of the variety and the versions of flight scripts. Developers became accustomed to preparing scripts on their own co
9、mputer, exchanging them with others, and independently making changes. Hence, the scripts that were run out of home directories were not always sourced in a dependable way to MER workstations. With different versions of scripts found on different workstations- some of which would not work properly-
10、processes were not repeatable between workstations. Reference (2) may be a typical example. Because this caused operational issues for MER during Assembly, Test, and Launch Operations (ATLO, aka “Integration & Test“), a procedure was successfully implemented during ORTs in which these scripts were d
11、elivered to CM, installed on Mission Support Environment workstations, and notification sent to Flight Operations Team support personnel. Accordingly, procedures for the Juno (Reference (3) and GRAIL (Reference (4) projects place Class B, Class C, and Class D software under configuration control pri
12、or to ORTs. References: 1. P.J. Guske, “OCO (Orbiting Carbon Observatory) Project Lessons Learned Document (Final),“ JPL Document No. D-26172, July 7, 2009, Paragraph 3.2.5.2. “Confusion with upper and lower case letters,“ JPL Problem/Failure Report No. Z77058, August 7, 2002.3. “Juno Project: Missi
13、on System Configuration Management Plan, Preliminary Release,“ JPL Document No. D-49338, September 30, 2009, Paragraph 5.6, Page 18. https:/pdms.jpl.nasa.gov/CMTOOLS/DocProperties.aspx?objid=tjEvitaempirepdmpdsu-Wqi4. “Grail Project Software Management Plan,“ JPL Document No. D-38908, October 9, 200
14、8. http:/charlie-lib.jpl.nasa.gov/docushare/dsweb/Get/Document-280353/GRAIL_D38908_Initial_2008-10-09.docLesson(s) Learned: Project attention to the configuration control of flight scripts is likely to prevent the generation of unnecessary software iterations, improve the rigor of mission system eng
15、ineering processes, and ensure consistency in the test and operations environments.Recommendation(s): Place flight scripts under change control prior to ORT.Evidence of Recurrence Control Effectiveness: JPL has referenced this lesson learned as additional rationale and guidance supporting Paragraph
16、6.15.2.1 (“Engineering Practices: Configuration Management - Implementation“) in the Jet Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Lessons Learned Entry: 2476Propulsion Laboratory standard “Flight Project Practices, Rev. 7,“ JPL DocID 58032, Se
17、ptember 30, 2008.Documents Related to Lesson: N/AMission Directorate(s): a71 Space Operationsa71 Exploration Systemsa71 ScienceAdditional Key Phrase(s): a71 Additional Categories.Flight Operationsa71 Safety and Mission Assurance.Configuration Change Controla71 Mission Operations and Ground Support S
18、ystems.Mission operations systemsa71 Integration and Testinga71 Engineering Design (Phase C/D).Software Engineeringa71 Systems Engineering and Analysis.Engineering design and project processes and standardsa71 Additional Categories.Softwarea71 Program Management.Configuration and data managementa71
19、Program Management.Contractor relationshipsa71 Missions and Systems Requirements Definition.Configuration control and data managementa71 Additional Categories.Configuration Managementa71 Additional Categories.Standarda71 Additional Categories.Spacecrafta71 Additional Categories.Test & Verificationa7
20、1 Additional Categories.ComputersAdditional Info: a71 Project: Mars Exploration Rover (MER), Juno, Gravity Recovery and Interior Laboratory (GRAIL)Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Lessons Learned Entry: 2476Approval Info: a71 Approval Date: 2010-05-10a71 Approval Name: mbella71 Approval Organization: HQProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
