一 SSPARC 趣( Space Systems Architecture Lecture 3 Introduction to Tradespace Exploration Hugh McManus Metis Design Space Systems, Policy, and Architecture Research Consortium A joint venture of MIT, Stanford, Caltech& the Naval War College for the nro SSPARC Tradespace Exploration A process for understanding complex solutions to complex problems Allows informed"upfront "decisions and planning Most relevant to processes in these phases Concept System-Le Detail Testing and Production Development Design DesignRefinementRamp-Up Phases of Product Developm
Space Systems, Policy, and Architecture Research Consortium 1 Hugh McManus Space Systems, Policy, and Architecture Research Consortium A joint venture of MIT, Stanford, Caltech & the Naval War College for the NRO ©2002 Massachusetts Institute of Technology Space Systems Architecture Lecture 3 Introduction to Tradespace Exploration Metis Design Space Systems, Policy, and Architecture Research Consortium 2 • • Concept Development System-Level Design Detail Design Testing and Refinement Production Ramp-Up Product Design and Development, 1995 Phases of Most relevant to processes in these phases ©2002 Massachusetts Institute of Technology Tradespace Exploration A process for understanding complex solutions to complex problems Allows informed “upfront” decisions and planning Product Development From Ulrich & Eppinger, 1
一 SSPARC Architecture Trade space exploration A process for understanding complex solutions to complex problems Model-based high-level assessment of system capability Ideally, many architectures assessed Avoids optimized point solutions that will not support evolution in environment or user needs Provides a basis to explore technical and policy uncertainties Provides a way to assess the value of potential capabilities Allows informed"upfront"decisions and planning SSPARC Integrated Concurrent Engineering A process creating preliminary designs very fast State-of-the-art rapid preliminary design method Design tools linked both electronically and by co-located Design sessions iterate/converge designs in hours Requires ready tools, well poised requirements Allows rapid reality check on chosen architectures Aids transition to detailed design
Space Systems, Policy, and Architecture Research Consortium 3 • • Ideally, many architectures assessed • Avoids optimized point solutions that will not support evolution in environment or user needs • Provides a basis to explore technical and policy uncertainties • Provides a way to assess the value of potential capabilities A process for understanding complex solutions to complex problems ©2002 Massachusetts Institute of Technology Architecture Trade Space Exploration Model-based high-level assessment of system capability Allows informed “upfront” decisions and planning Space Systems, Policy, and Architecture Research Consortium 4 • State-of-the-art rapid preliminary design method • Design tools linked both electronically and by co-located humans • Design sessions iterate/converge designs in hours • Requires ready tools, well poised requirements A process creating preliminary designs very fast Allows rapid reality check on chosen architectures Aids transition to detailed design ©2002 Massachusetts Institute of Technology Integrated Concurrent Engineering 2
SSPARC Emerging Capability Linked method for progressing from vague user needs to conceptual/preliminary design very quickly MANY architectures, several/many designs considered Understanding the trades allows selection of robust and adaptable concepts, consideration of policy, risk. ICE Robust Architecture Conceptual Adaptable evaluation Design Concepts Months, not Years SSPARC What is an Architecture Trade space? X-TOS a Case, New Utilities, ppo archs Small low-altitude science mission t Orbital Parameters rysical Spacecraft Parameters Total Lift围 Assessment of the utility and cost of a large space of possible system architectures
Number of Architectures Explored: 50488 Number of Architectures Explored: 50488 Space Systems, Policy, and Architecture Research Consortium 5 User Needs Robust Adaptable Concepts Months, not Years ICE Conceptual Design MATE Architecture Evaluation • Linked method for progressing from vague user needs to conceptual/preliminary design very quickly • MANY architectures, several/many designs considered • adaptable concepts, consideration of policy, risk. ©2002 Massachusetts Institute of Technology Emerging Capability Understanding the trades allows selection of robust and Space Systems, Policy, and Architecture Research Consortium 6 km Km DESIGN VARIABLES: The architectural trade parameters • Orbital Parameters – Apogee altitude (km) – Perigee altitude (km) – Orbit inclination 150-1100 150-1100 0, 30, 60, 90 • Physical Spacecraft Parameters – Antenna gain – communication architecture – propulsion type – power type – delta_v Total Lifecycle Cost ($M2002) a specific architecture Assessment of the utility and cost of a large space of possible system architectures X-TOS • Small low-altitude science mission ©2002 Massachusetts Institute of Technology What is an Architecture Trade Space? Each point is 3
一 SSPARC Developing A Trade space Attributes Define Design Understand the Vector Mission Create a list of Develop System Attributes Model · Interview the Customer Calculate Create Utility Curves+ Utility Estimate Develop the design Cost vector and system model Evaluate the potential Architecture Architectures Trade Space SSPARC XTOS Tradespace Development Data Life Span Diversity of Latitude(s Time Spent at Equator Design Vector Define Utilit 吗M Power Typ Delta-V Capabi ty
Space Systems, Policy, and Architecture Research Consortium 7 • Understand the Mission • Create a list of • Interview the Customer • Create Utility Curves • Develop the design model • Evaluate the potential Architectures Mission Concept Attributes Calculate Utility Develop System Model Estimate Cost Architecture Define Design Vector ©2002 Massachusetts Institute of Technology “Attributes” vector and system Trade Space Developing A Trade Space Space Systems, Policy, and Architecture Research Consortium 8 Concept • Small low-altitude science mission • Known instruments Attributes • Data Life Span • Data Collection Altitude(s) • Diversity of Latitude(s) • Time Spent at Equator • Data Latency • Number of Vehicles and Mission Design • Apogee Altitude • Perigee Altitude • Orbit Inclination • Antenna Gain • Communications Architecture • Propulsion Type • Power Type • 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 150 350 550 750 950 Data Collection Altitude (km) Utility ©2002 Massachusetts Institute of Technology XTOS Tradespace Development Design Vector Manuever Delta-V Capability Define Utility 4
一 SSPARC Continued acecraft Estimations(SMAD) Launch module Calculate Utility Estimate Cost Multi-Attribute Utility Theory saaRc I:ii SSPARC Understanding What Systems Do Transmit Information Collect Information Move Mass (inc. People Others(Space Station
Space Systems, Policy, and Architecture Research Consortium 9 Continued Total Lifecycle Cost ($M2002) Each point is a specific architecture • Orbit Calculations (STK) • Spacecraft Estimations (SMAD) • Launch Module 50488 Architectures Explored • Multi-Attribute Utility Theory • SMAD/NASA mode architectures ©2002 Massachusetts Institute of Technology System Model Calculate Utility Estimate Cost Pareto front of “best” Space Systems, Policy, and Architecture Research Consortium 10 • • • • ) © 2002 Massachusetts Institute of Technology Understanding What Systems Do Transmit Information Collect Information Move Mass (inc. People) Others (Space Station… [Beichman et al, 1999] 5 Martin 2000
SSPARC Understanding who cares Stakeholder Many interested parties in a complex system ·Each“ customer has a set of needs They are different, and can be contradictory Enterprise Emplayees Corporation SSPARC Concept Selection: Bounding ATOS Multi-vehicle Ionosphere Explorer Situ Topside Sounding Direct Scintillation Sensing GPS Occultation UV Sensing
Space Systems, Policy, and Architecture Research Consortium 11 Stakeholders • • • Enterprise Employees Corporation Customer End Users Consumers Acquirers Shareholders Society Unions Partners Suppliers ©2002 Massachusetts Institute of Technology Understanding who cares - Many interested parties in a complex system Each “customer” has a set of needs They are different, and can be contradictory Space Systems, Policy, and Architecture Research Consortium 12 ATOS: Multi-vehicle Ionosphere Explorer In Situ Topside Sounding Direct Scintillation Sensing GPS Occultation GPS UV Sensing ©2002 Massachusetts Institute of Technology Concept Selection: Bounding 6
一 SSPARC Scoping A-TOS scope I SSPARC Attribute "what the decision makers need to and/or what the user truly cares about) Examples: Billable minutes= GINA metrics · TPF Pictures= camera performance metrIcs Rescue/move satellites mass moving, grappling capability, timeliness Could have sub-cartoons for above
©2002 Massachusetts Institute of Technology 14 Space Systems, Policy, and Architecture Research Consortium 13 Scoping Spacecraft Instrument Control Center Physics Model Instrument -> Local Ionosphere Current State Predict Future State User-Specific System Integration User Set User Set User Set User Set Ionospheric characteristics Database Other Data Sources (Various assets) A-TOS scope Ionosphere ©2002 Massachusetts Institute of Technology Global Ionospheric Model Global Ionospheric Model Hanscom Model Raw, commutated, uncalibrated data Decommutated, calibrated instrument data “Scientist” “Warfighter” “Space Weather” “Knowledgeable” Go/No-Go “green light” Space Systems, Policy, and Architecture Research Consortium Attributes • “what the decision makers need to consider” • ( and/or what the user truly cares about) • Examples: Billable minutes = • TPF Pictures = camera performance metrics • Rescue/move satellites = mass moving, grappling capability, timeliness – Could have sub-cartoons for above GINA metrics [Beichman et al, 1999] 7
一 SSPARC XTOS Attributes (1) 2) 1) Data Life Span 2)Data Altitude 3)Maximum Latitude 4)Time Spent at Equator 2004 2005 5)Data Late (3) (5) SSPARC Utilities What the attributes are Worth to the decision makers” Single attribute utility maps attribute to utility Multi-attribute utility maps an architecture(as expressed by its attributes) to utility ∧ 8 Single Attribute Multi-Attribute Utility fu nction Utility analy
DATA Space Systems, Policy, and Architecture Research Consortium 15 (3) (4) (5) (1) (2) 1) Data Life Span 2) Data Altitude 3) Maximum Latitude 4) Time Spent at Equator 5) Data Latency km Km 2004 2005 ©2002 Massachusetts Institute of Technology XTOS Attributes Space Systems, Policy, and Architecture Research Consortium 16 Utilities • • • Single Attribute Utility function 0 1 Good -> Attribute Multi-Attribute Utility analysis 0 1 Good -> Expense ©2002 Massachusetts Institute of Technology “What the attributes are WORTH to the decision makers” Single Attribute utility maps attribute to utility Multi-attribute utility maps an architecture (as expressed by its attributes) to utility 8
一 SSPARC Single attribute utilities SSPARC Multi-Attribute Utility U(X+1-(KkU(x)+1) # isE Total Lifecycle Cost(SM 2002)
9 Space Systems, Policy, and Architecture Research Consortium ©2002 Massachusetts Institute of Technology 17 Single Attribute Utilities 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 150 350 550 750 950 Data Collection Altitude (km) Utility Space Systems, Policy, and Architecture Research Consortium ©2002 Massachusetts Institute of Technology 18 Multi-Attribute Utility Single Attribute Utility Curve for Data Point Altitude 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 150 350 550 750 950 Altitude (km) 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 Lifespan Latitude Latency Equator Time Altitude Weight Factors of each Attribute (k values) ’( ) = =+ + N i KU X Kk XU ii 1 1)( 1)( Total Lifecycle Cost ($M 2002) Utility
SSPARC XTOS Design vector Parameters of the Trade space First Order Effec Orbital Parameters altitude(200 to 2000 km) ne. Altitude perigee altitud 50km) Orbit inclination(0 to 90 degrees) titude Range uator Physical Spacecraft Parameters: Latency comm architechture(TDRSS/AFSCN) bility(200 to 1000 m/s) SSPARC aTos design vector Geometry of the Multi-vehicle Swarm Swarm Orbit Parameters Number of spacecraft in swarm Geometry of swarm
XTOS Design Vector • “Parameters of the Trade Space” Variable: First Order Effect: Orbital Parameters: •Apogee altitude (200 to 2000 km) Lifetime, Altitude •Perigee altitude (150 to 350 km) Lifetime, Altitude •Orbit inclination (0 to 90 degrees) Lifetime, Altitude Latitude Range Time at Equator Physical Spacecraft Parameters: •Antenna gain (low/high) Latency •Comm Architechture (TDRSS/AFSCN) Latency •Propulsion type (Hall / Chemical) Lifetime •Power type (fuel / solar) Lifetime •Total DV capability (200 to 1000 m/s) Lifetime Space Systems, Policy, and Architecture Research Consortium ©2002 Massachusetts Institute of Technology 19 Space Systems, Policy, and Architecture Research Consortium 20 • mothership ©2002 Massachusetts Institute of Technology ATOS design Vector Geometry of the Multi-vehicle Swarm Swarm Orbit Parameters Mothership/ no Number of spacecraft in swarm Geometry of swarm 10
