![Space Systems Engineering
ENAE 483/788D - Principles of Space Systems Design
U N I V E R S I T Y O F
MARYLAND
References (Available on Web Site)
• NASA Systems Engineering Handbook - SP-6105 - June, 1995 [2.3 Mb, 164 pgs.]
(Obsolete, but nice description of NASA's systems engineering approach)
• NASA Systems Engineering Processes and Requirements - NPR 7123.1A - March
26, 2007 [3.6 Mb, 97 pgs.] (Current version - pages are almost impossible to read without a
magnifying glass)
• NASA Space Flight Program and Project Management Requirements - NPR
7120.5D - March 6, 2007 [2.7 Mb, 50 pgs.] (Current version - pages are almost impossible
to read without a magnifying glass)
• NASA Program and Project Management Processes and Requirements - NPR
7120.5C - March 22, 2005 [1.9 Mb, 174 pgs.] (Older, superceded version, but includes more
figures and is readable by mere mortals)
• NASA Goddard Space Flight Center Procedures and Guidelines: Systems
Engineering - GPG 7120.5B - 2002 [1.7 Mb, 31 pgs.]
• NASA Goddard Space Flight Center Mission Design Processes (The "Green Book")
[860 Kb, 54 pgs.]
49](https://image.slidesharecdn.com/483f09l02-241123165635-2931f1a0/85/PrincipalDesignSpaceSystemsEngineering-pdf-49-320.jpg)
PrincipalDesignSpaceSystemsEngineering.pdf
- 1. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Space Systems Engineering 1 • Background of Systems Engineering • NASA program planning phases • Scheduled milestones • Requirements document • Work breakdown structure • Technology readiness levels • Project management tools • Design reference missions and CONOPS • Earned value management • Risk tracking © 2009 David L. Akin - All rights reserved http://spacecraft.ssl.umd.edu
- 2. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Schedule Updates • Special lecture Friday 9/4 - Orbital Mechanics 1:00-2:30pm ITV1111 • Special lecture Friday 9/11 - Rover Design 2 1:00-2:30pm ITV1111 • No lectures on Tuesday 9/15 and Thursday 9/17 - meet with your preliminary design teams! 2
- 3. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Assigned Groups for Initial Design Project Team Gamma Gregory Holste Rodric Richenberg Ji-Hyoung Woo Wayne Yu Albert Zhou Team Delta James Doggett Justin Hill Samantha Lustig Christopher Mak Robert Wagner Timothy White Team Alpha Jayne Breitwieser Andrew Britton Kevin Davis Brandon Hall Marissa Intelisano Leon Manfredi Team Beta Jennifer Donaldson Taylor Feiereisel Zachary Gonnsen Brandon Litt Lauren Puglisi 3 Team Epsilon Kevin Buckley Ricardo Gutierrez Laura Meyer Elaine Petro Tut Gatyiel
- 4. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Overview of Systems Engineering • Developed to handle large, complex systems – Geographically disparate – Cutting-edge technologies – Significant time/cost constraints – Failure-critical • First wide-spread applications in aerospace programs of the 1950’s (e.g., ICBMs) • Rigorous, systematic approach to organization and record-keeping 4
- 5. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND NASA Lifecycle Overview 5
- 6. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND NASA Formulation Stage Overview 6
- 7. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Space Systems Development Process Pre-Phase A Conceptual Design Phase Development of performance goals and requirements Establishment of Science Working Group (science missions) Trade studies of mission concepts Feasibility and preliminary cost analyses Request for Phase A proposals 7
- 8. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Space Systems Development Process Pre-Phase A Phase A Preliminary Analysis Phase Proof of concept analyses Mission operations concepts “Build vs. buy” decisions Payload definition Selection of experimenters Detailed trajectory analysis Target program schedule RFP for Phase B studies 8
- 9. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Space Systems Development Process Pre-Phase A Phase B Phase A Definition Phase Define baseline technical solutions Create requirements document Significant reviews: Systems Requirements Review Systems Design Review Non-Advocate Review Request for Phase C/D proposals 9
- 10. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Historical Implications of Study Phases 10 from J. A. Moody, ed., Metrics and Case Studies for Evaluating Engineering Designs Prentice-Hall, 1997
- 11. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Implementation Stage Overview 11
- 12. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Space Systems Development Process Pre-Phase A Phase C/D Phase B Phase A Development Phase Detailed design process “Cutting metal” Test and analysis Significant reviews: Preliminary Design Review (PDR) Critical Design Review (CDR) Test Acceptance Review Flight Readiness Review Ends at launch of vehicle 12
- 13. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND The Space Systems Development Pre-Phase A Phase E/F Phase C/D Phase B Phase A Operations and End-of-Life Launch On-orbit Check-out Mission Operations Maintenance and Troubleshooting Failure monitoring End-of-life disposal 13
- 14. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND NASA Project Life Cycle - Milestones 14 from NASA SP-2007-6105 rev. 1, “NASA Systems Engineering Handbook”
- 15. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND NASA Project Life Cycle - Acronyms 15 from NASA SP-2007-6105 rev. 1, “NASA Systems Engineering Handbook”
- 16. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND ASUMD* Program Goals • To design a astronaut support vehicle that is compatible with Constellation architecture and supports exploration objectives • To design and develop a function prototype of the ASUMD for field testing in support of project design activities • To disseminate information on ASUMD feasibility and utility to decision makers at NASA and elsewhere *(feel free come up with a better name...) 16
- 17. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND ASUMD Program Objectives • Design a robotic rover capable of performing both autonomous and human-assistant tasks for lunar exploration • Examine possible requirements for operational performance (e.g., range, speed, payload, capabilities) to maximize the likelihood of program approval and field utility • The rover must be capable of launching on an Altair landing vehicle with minimal impact to critical down-payload 17
- 18. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Requirements Document • The “bible” of the design and development process • Lists (clearly, unambiguously, numerically) what is required to successfully complete the program • Requirements “flow-down” results in successively finer levels of detail • May be subject to change as state of knowledge grows • Critical tool for maintaining program budgets 18
- 19. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Design is based on requirements. There's no justification for designing something one bit "better" than the requirements dictate. Akin’s Laws of Spacecraft Design - #13 19
- 20. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Interface Control Documents • Used to clearly specify interfaces (mechanical, electrical, data, etc.) between mating systems • Critical since systems may not be fit-checked until assembled on-orbit! • Success of a program may be driven by careful choices of interfaces • KISS principle holds here (“keep it simple, stupid”) 20
- 21. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Akin’s Laws of Spacecraft Design - #15 (Shea's Law) The ability to improve a design occurs primarily at the interfaces. This is also the prime location for screwing it up. 21
- 22. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Work Breakdown Structures • Detailed “outline” of all tasks required to develop and operate the system • Successively finer levels of detail – Program (e.g., Constellation Program) – Project (Lunar Exploration) – Mission (Lunar Sortie Exploration) – System (Pressurized Rover) – Subsystem (Life Support System) – Assembly (CO2 Scrubber System) – Subassembly, Component, Part, ... 22
- 23. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND NASA Standard WBS Levels 1 & 2 23
- 24. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND 24 Standard WBS for JPL Mission Foreign Travel/ITAR 01.07 Facilities 01.06 Review Support 01.05 Project Plng Spt 01.04 Risk Mgmnt 01.03 Business Mgmnt 01.02 Project Mgmnt 01.01 Project Management 01 Project V&V 02.08 Launch Sys Eng 02.07 Planetary Protection 02.06 Config Mgmnt 02.05 Information Systems 02.04 Project SW Eng 02.03 Mission & Nav Design 02.02 Project Sys Eng 02.01 Project Sys Eng 02 SW IV&V 03.09 Contamination Control 03.08 SW Q&A 03.07 HW Q&A 03.06 EEE Parts Eng 03.05 Reliability 03.04 Environments 03.03 System Safety 03.02 MA Mgmnt 03.01 Mission Assurance 03 Education & Outreach 04.06 Sci Environment Characterization 04.05 Sci Investigatio & Ops Spt 04.04 Sci Data Support 04.03 Science Team 04.02 Science Mgmnt 04.01 Science 04 P/L I&T 05.06 Common P/L Systems 05.05 Instrument N 05.04 Instrument 1 05.03 P/L Sys Eng 05.02 P/L Mgmnt 05.01 Payload 05 Spacecraft assembly test & verification 06.12 Testbeds 06.11 Spacecraft Flt SW 06.10 GN&C Subsys 06.09 Propulsion Subsys 06.08 Thermal Subsys 06.07 Mechanical Subsys 06.06 Telecomm Subsys 06.05 Command & Data S/s 06.04 Power Subsys 06.03 Flt Sys - Sys Eng 06.02 Flt Sys Mgmnt 06.01 Spacecraft Contract 06.00 Flight System 06 MOS V&V 07.05 Operations 07.04 Ground Data Sys 07.03 MOS Sys Eng 07.02 Mission Ops Mgmnt 07.01 Mission Ops System 07 Launch Services 08.01 Launch System 08 Project Name WBS Levels 1 2 3
- 25. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Detail in JPL “Flight Systems” Column 1. Spacecraft Contract 2. Flight Systems Management 3. Flight Systems - Systems Engineering 4. Power Systems 5. Command and Data Handling Systems 6. Telecommunications Systems 7. Mechanical Systems 8. Thermal Systems 9. Propulsion Systems 10.Guidance, Navigation, and Control Systems 11.Spacecraft Flight Software 12.Testbeds 13.Spacecraft Assembly, Test, and Verification 25
- 26. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Akin’s Laws of Spacecraft Design - #24 It's called a "Work Breakdown Structure" because the Work remaining will grow until you have a Breakdown, unless you enforce some Structure on it. 26
- 27. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Technology Readiness Levels TRL 9 Actual system “flight proven” through successful mission operations TRL 8 Actual system completed and “flight qualified” through test and demonstration TRL 7 System prototype demonstration in the real environment TRL 6 System/subsystem model or prototype demonstration in a relevant environment TRL 5 Component and/or breadboard validation in relevant environment TRL 4 Component and/or breadboard validation in laboratory environment TRL 3 Analytical and experimental critical function and/or characteristic proof-of-concept TRL 2 Technology concept and/or application formulated TRL 1 Basic principles observed and reported 27
- 28. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND PERT* Charts Task Title Slack Time Task Duration Earliest Starting Date Earliest Completion Date *Program Evaluation and Review Technique 28
- 29. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND The Critical Path and Slack Time 29
- 30. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND The Critical Path and Slack Time 30
- 31. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Cascading Slack Time 31
- 32. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Gantt* Charts I D Task Name Duration S t a r t F i n i s h P r e d e c e s s o r s 1 Design Robot 4 w Tue 9/3/02 Mon 9/30/02 2 Build Head 6 w Tue 10/1/02 Mon 11/11/02 1 3 Build Body 4 w Tue 10/1/02 Mon 10/28/02 1 4 Build Legs 3 w Tue 10/1/02 Mon 10/21/02 1 5 Assemble 2 w Tue 11/12/02 Mon 11/25/02 2,3,4 9/1 9/8 9/15 9/22 9/29 10/6 10/13 10/20 10/27 11/3 11/10 11/17 11/24 12/1 1 September October November *developed by Charles Gantt in 1917 32
- 33. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Some Pitfalls of Project Management 33
- 34. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Akin’s Laws of Spacecraft Design - #23 The schedule you develop will seem like a complete work of fiction up until the time your customer fires you for not meeting it. 34
- 35. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Design Reference Missions • Description of canonical mission(s) for use in design processes • Could take the form of a narrative, storyboard, pictogram, timeline, or combination thereof • Greater degree of detail where needed (e.g., surface operations) • Created by eventual users of the system (“stakeholders”) very early in development cycle 35
- 36. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Concept of Operations • Description of how the proposed system will accomplish the design reference mission(s) • Will appear to be similar to DRM, but is a product of the design, rather than a driving requirement • Frequently referred to as “CONOPS”, showing DOD origins 36
- 37. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Space Systems Architecture • Description of physical hardware, processes, and operations to perform DRM • Term is used widely (e.g., “software architecture”, “mission architecture”, “planning architecture”), but refers to basic configuration decisions • Generally result of significant trade studies to compare options 37
- 38. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND ESAS Final Architecture/CONOPS 38
- 39. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Earned Value Management • Consider a simple program with four two-month tasks that are expected to cost various amounts 39 $4 M $10 M $6 M $8 M 1 2 3 4 Months 5 $2M $7M $8M $7M Planned monthly costs $4M
- 40. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Program Cost Accounting • Traditionally monitored by “burn rate” - cumulative expenditures with time 40 0 5 10 15 20 25 0 1 2 3 4 5 Months Costs ($M) Cumulative
- 41. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Earned Value Management - Month 1 • In the first month, you complete 60% of task 1 and 10% of task 2 • Actual costs for month 1 = $3 M EV=$3.4 M 41 $4 M $10 M $6 M $8 M 1 2 3 4 Months 5 EV(1)=0.6*4=$2.4 M EV(2)=0.1*10=$1 M
- 42. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Earned Value Management - Month 2 • In the second month, you complete 100% of task 1 and 60% of task 2 • Actual costs for month 2 = $10 M EV=$10 M 42 $4 M $10 M $6 M $8 M 1 2 3 4 Months 5 EV(1)=1.0*4=$4 M EV(2)=0.6*10=$6 M
- 43. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Earned Value Management - Month 3 • In the third month, you complete 100% of task 1, 80% of task 2, and 40% of task 3 • Actual costs for month 3 = $16 M EV=$14.4 M 43 $4 M $10 M $6 M $8 M 1 2 3 4 Months 5 EV(1)=1.0*4=$4 M EV(2)=0.8*10=$8 M EV(3)=0.4*6=$2.4 M
- 44. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND 0 5 10 15 20 25 0 1 2 3 4 5 Months Costs ($M) Cumulative Actual Program Cost Accounting - Tracking • Plotting actual costs vs. time shows how money is spent, but doesn’t tell anything about how much work has been accomplished 44
- 45. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND • Earned value tracks accomplishments against their planned costs • Variation shows schedule performance 0 5 10 15 20 25 0 1 2 3 4 5 Months Costs ($M) Cumulative Earned Value Program Cost Accounting - Tracking 45
- 46. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND 0 5 10 15 20 25 0 1 2 3 4 5 Months Costs ($M) Cumulative Earned Value Actual • Comparing earned value to actual costs shows “apples to apples” comparison of money spent and value achieved Program Cost Accounting - Tracking 46
- 47. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Decision Analysis Tools • A number of different approaches exist, e.g. – Pugh Matrices – Quality Function Deployment – Analytic Hierarchy Process • Generally provide a way to make decisions where no single clear analytical metric exists - “quantifying opinions” • Allows use of subjective rankings between criteria to create numerical weightings • Not a substitute for rigorous analysis! 47
- 48. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND Risk Matrix 48
- 49. Space Systems Engineering ENAE 483/788D - Principles of Space Systems Design U N I V E R S I T Y O F MARYLAND References (Available on Web Site) • NASA Systems Engineering Handbook - SP-6105 - June, 1995 [2.3 Mb, 164 pgs.] (Obsolete, but nice description of NASA's systems engineering approach) • NASA Systems Engineering Processes and Requirements - NPR 7123.1A - March 26, 2007 [3.6 Mb, 97 pgs.] (Current version - pages are almost impossible to read without a magnifying glass) • NASA Space Flight Program and Project Management Requirements - NPR 7120.5D - March 6, 2007 [2.7 Mb, 50 pgs.] (Current version - pages are almost impossible to read without a magnifying glass) • NASA Program and Project Management Processes and Requirements - NPR 7120.5C - March 22, 2005 [1.9 Mb, 174 pgs.] (Older, superceded version, but includes more figures and is readable by mere mortals) • NASA Goddard Space Flight Center Procedures and Guidelines: Systems Engineering - GPG 7120.5B - 2002 [1.7 Mb, 31 pgs.] • NASA Goddard Space Flight Center Mission Design Processes (The "Green Book") [860 Kb, 54 pgs.] 49