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Systems Engineering Goddard's GPR Guideline, Mission Concept Studies, and Support Tools. John Azzolini Systems Engineering Services and Advanced Concepts Branch September 2005. Agenda. A Brief Overview Of GPR 7120.5A Concepts
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Systems Engineering Goddard's GPR Guideline, Mission Concept Studies, and Support Tools John Azzolini Systems Engineering Services and Advanced Concepts Branch September 2005
Agenda • A Brief Overview Of GPR 7120.5A Concepts • An Examination Of The Pre-phase A Concept Study To Illustrate The Guidelines • A Demonstration Of A Systems Engineering Validation Support Tool GSFC Systems Engineering Seminar - 9/13/05
Overview of GPR 7120.5A What is the GPR? • A practical definition of what should be done as a part of good systems engineering practice • Based on the NASA Systems Engineering Handbook SP-6105 • Incorporates principles of industry systems engineering standards Why do we have it? • Correct deficiencies in the execution of systems engineering. (Many of the root causes of Aerospace Industry failures were traced to poor systems engineering) • Describe what constitutes good systems engineering • Improve uniformity of systems engineering in completeness and quality How can it be useful? • Serves as a set of reminders for what should be considered • Provides guidance for establishing a project unique systems engineering plan • Provide common understanding and expectations within the Goddard systems engineering community GSFC Systems Engineering Seminar - 9/13/05
Overview of GPR 7120.5A Principles • Encourage a Team Approach • Cover full mission life-cycle • Define the whats • Show product maturity over life-cycle • Stress Validation • Keep good practices of the past GSFC Systems Engineering Seminar - 9/13/05
Overview of GPR 7120.5A Document Contents • Preface – Purpose, Applicability, Authority, References, Cancellation, Safety, Training, Records, Metrics, Definitions • Roles and Responsibilities • Communications • Key Systems Engineering Functions • Configuration Management and Documentation • Systems Engineering Management Plan • App A - Systems Engineering Requirements • App B - System Engineering Management Plan Outline • App C - Tailoring Guidelines GSFC Systems Engineering Seminar - 9/13/05
Overview of GPR 7120.5A Roles And Responsibilities • Project or study manager teams with Mission Systems Engineer • Mission Systems Engineer coordinates and facilitates team • SEMP describes details GSFC Systems Engineering Seminar - 9/13/05
System Engineering Life-cycle Overview of GPR 7120.5A GSFC Systems Engineering Seminar - 9/13/05
Perhaps the most important skill a system engineer needs… … is the ability to build a team of engaged, focused, and productive players. Overview of GPR 7120.5A Communications • Systems Engineering is a Team Activity • The Mission System Engineer facilitates and coordinates team effort • Solutions converge when decisions are made • Validation is the job of all team members GSFC Systems Engineering Seminar - 9/13/05
Overview of GPR 7120.5A The organization of information, to understand our goals, … Key Systems Engineering Functions • Understanding the Objectives • Operations Concept Development • Architecture and Design Development • Requirements Identification and Management • Validation and Verification • Interfaces and ICDs • Mission Environments • Technical Resource Budget Tracking • Risk Management • System Milestone Reviews … and to systematically achieve them . GSFC Systems Engineering Seminar - 9/13/05
Overview of GPR 7120.5A Maintaining information which accurately reflects our decisions … Configuration Management and Documentation • Identify information products which must be “configured” • Use project CM system to maintain • Single point of configuration • Change control at the appropriate time … to assure integrated success . GSFC Systems Engineering Seminar - 9/13/05
Overview of GPR 7120.5A “Plans are nothing - … Systems Engineering Management Plan • What, who, when, where, how • An active plan, it is updated and used to plan efforts • Products defined • Tasks defined • Schedule maintained • Costs maintained … planning is everything” – Dwight Eisenhower. GSFC Systems Engineering Seminar - 9/13/05
Mission Concept StudyPre-phase A Understanding and Implementing the GPR GSFC Systems Engineering Seminar - 9/13/05
Mission Concept Study • Back to the SE functions • Understanding the Objectives • Operations Concept Development • Architecture and Design Development • Requirements Identification and Management • Validation and Verification • Interfaces and ICDs • Mission Environments • Technical Resource Budget Tracking • Risk Management • System Milestone Reviews • What is known? What needs to be known? • Let’s start at the very beginning GSFC Systems Engineering Seminar - 9/13/05
Mission Concept Study “All the worst mistakes … Mission Objectives Mission Needs is a better term … are made the first day” – Anon. GSFC Systems Engineering Seminar - 9/13/05
Mission Concept Study Mission Needs for Other NASA Mission Types GSFC Systems Engineering Seminar - 9/13/05
Mission Concept Study Design Specification and Validation Flows GSFC Systems Engineering Seminar - 9/13/05
Mission Concept Study Mission Design … Payload Concept … depends on payload design. GSFC Systems Engineering Seminar - 9/13/05
Mission Concept Study Partitioning of functionality … Mission Design … between space and groundis made here. GSFC Systems Engineering Seminar - 9/13/05
Mission Concept Study And now … System Design Instrument Accommodation Requirements Mission System Requirements Spacecraft Design Ground System Design Launch Accommodations Mission Architecture Mission Operations Concept … system design can proceed. GSFC Systems Engineering Seminar - 9/13/05
Mission Concept Study A continuing validation of products … Verification and Validation Validation - Assuring that the design is correct (“Did we build the right system?”) • Validation of mission needs flow-down (“flow of authority”) (necessary) • Validation of design compliance to needs (sufficient) • Functionality • Performance Analysis Verification - Assuring that the implementation is correct (“Did we build the system right?”) • Testing, analysis, and inspection • Verification of function and performance • Verification of implementation • Verification of operations Note: Many people (erroneously, in my opinion) call end-item operational verification – “Validation” – Pshaw! … keeps the team coordinated. GSFC Systems Engineering Seminar - 9/13/05
Payload Concept Mission Concept Study Putting it all together … Mission Needs Mission Design System Design … for a complete validation of design. GSFC Systems Engineering Seminar - 9/13/05
Mission Concept Study Good interface requirements and interface control documents … Interface Requirements and ICDs • Interface Requirements • Functional • Performance • Standards Compliance • Interface Control Documents • Function • Form • Specifications • Properties Covered • Mechanical • Electrical • Thermal • Power • Ground • … … allow decoupling of implementation efforts. GSFC Systems Engineering Seminar - 9/13/05
Launch Environment GEVS Mechanical – Sine, Sine Sweep, Acoustic Electrical - EMI, EMC Shock External RF External Space Environment Atomic Oxygen Radiation TID Radiation SEE Thermal Cycling Power Cycling Internal Environment Grounding Noise Power Surges Mission Concept Study Determine mission environments early … Mission Environments … and apply uniformly. GSFC Systems Engineering Seminar - 9/13/05
Mission Concept Study “Everything depends on … Mission Technical Resources Mass – Affects launch margin, ACS, propellant Power – Affects mass, thermal dissipation Thermal – Affects Alignment, Life, calibration Attitude – Affects measurement resolution, image smearing Position – Affects orbit dependent aspect knowledge Data – Affects bandwidth, link margin, storage RF – Affects power, mass Essentially all the things where margins are defined … everything” – old systems engineering adage. GSFC Systems Engineering Seminar - 9/13/05
Mission Concept Study Mission risks … Mission Risks Safety Risks • Hazard analyses are the prime method to identify safety risks • Project management should understand and manage safety risks Performance Risks • FMEA, FTA, RBD and PRA are good tools here • Sound design practices, simple robust designs, and adequate peer review • High to low risks often on a logarithmic scale • Project management should understand and manage performance risks Programmatic Risks • Schedule, Cost • Classical FMEA, FTA, RBD do not apply here, • Communication and continuous assessment of progress • High to low risks often on a linear scale • Element lead and/or project management has responsibility for managing programmatic risks … are of three distinct types. GSFC Systems Engineering Seminar - 9/13/05
Mission Concept Study Product Maturity and Reviews GSFC Systems Engineering Seminar - 9/13/05
A Systems EngineeringValidation Support Tool Caveat: A fool with a tool is still a fool GSFC Systems Engineering Seminar - 9/13/05
In closing . . . Come my friends, ‘tis not too late to seek a newer world.Push off, and sitting well in order smitethe surrounding furrows; for my purpose holdsto sail beyond the sunset, and the bathsof all the western stars, until I die. - A. Lord Tennyson, Ulysses GSFC Systems Engineering Seminar - 9/13/05