Transcript Multi-Discipline Design Analysis & Optimization (MDAO)

Multi-Discipline Design Analysis
& Optimization (MDAO)
ICEAA Conference,
March 18, 2015, SMC
(Fort McArthur),
San Pedro, CA
Tom Harwick
MDAO – Cost Engineer
Concept & Preliminary Design Engineering Cost
models & Methods
Northrop Grumman, El Segundo, CA
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
MDAO Cost Modeling
• Topics
– Objectives of MDAO (What, Why)
– MDAO Overview
– Model Center (Phoenix Integration), & Cost Models
– Design-of-Experiments (DOE) Simulation Process within MDAO
– Conclusions
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
MDAO at Northrop Grumman Aerospace Systems
(NGAS)
• A way of tying together design, modeling, simulation and analysis multidisciplinary tools to understand the Big Picture
– May be applied to Sys-of-Sys, Systems design and Subsystems design
Problems
• Understand how variance in input variables
affect output variables
– Topology Trades ( A vs. B, which is “better?” )
– Sizing Trades ( how big should A1,A2,A3,A4 be to make A
“work”)
– Optimality Trades (what collection of A1,A2,A3,A4 forms the
“best” design?)
– Uncertainty / Robustness Trades ( what is the impact of
uncertainty in terms of system performance? feasibility? )
Automates our tools for improved cost effectiveness in engineering
design, modeling, simulation & analysis processes
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
MDAO Infrastructure
Systematically links CAD and Analytical Systems with LCC and OA
ModelCenter used to link CATIA with data bases & engineering analysis
Aircraft Design
& Analysis
Configuration
Ops Analysis
& Life Cycle Cost
Analysis Library
ModelCenter
Life-Cycle Cost
Low
Observables
OA Mission
Effectiveness
Aerodynamics
System Options:
• Can support team co-located (similar
to ICE) or distributed
• Can be deployed throughout any
linked network environment
• and, can be deployed & installed in
any isolated compartment
Propulsion
Mass Properties
Operations &
Support
Manufacturing &
Assembly
Collaboration Sys
Document Mgmt
Performance
Subsystems
Structures
Loads &
Dynamics
Stability &
Control
Provides infrastructure across sector integrating common tools and best practices for affordability
and first-time engineering quality in a collaborative environment
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
Picture of CATIA Model Performing an Iteration
within Model Center (Performance/Design/Cost)
CATIA model is Embedded within the Design Models in Model Center
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
MDAO (MBE) based Design & Analysis Cycle (DAC)
Process Summary
1. Problem Definition
(Requirements,
Independent Variables
and KPP’s)
K
C
B
L A
I
D
H
E F
4. Identify
Discipline
Models, Fidelity,
Interfaces and
V&V
(N2 Diagram)
5. Design Space
Exploration,
Preferred
Sensitivities & Configuration(s)
Optimization
(Optimization)
Design
Space
Exploration
G
KPP
J
2. Concept
Development
(Sizing)
3. Parametric
Model
Development
(Configuration)
Discipline
Review
Configuration
Selection
Radius (nm)
Customers, Stakeholders and Suppliers
1. Problem Definition (Requirements, Constraints, Independent Variables & KPPs)
2. Concept Development (sizing) – how big and what type, e.g. wing/body/tail, flying wing, biplane, etc.
3. Parametric Model Development (configuration) – Develop parametric CAD model that integrates key driving
geometric considerations: wetted area, aspect ratio, t/c, weapons bay, propulsion integration, fuel volumes, avionics,
mission systems, subsystems, VMS, (SWAP), etc. . . .
4. Identify Discipline Models, Fidelity levels, Model Interfaces and V&V
- N^2 Diagram (I/O) includes: Cost, Propulsion, Structures , Aerodynamics, Mass Properties, Performance, ……
5. Design Space Exploration, Sensitivity Analysis, Constraint Assessment and
Optimization Trade Studies - lead to proposed preferred configuration(s) for further detailed analysis
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
Create Cost Model (Object) in Model Center
- with Interfaces to other Engineering Design Models (Objects)
•
Select Cost Model
–
–
•
Determine cost sensitivity required, inputs & outputs, and accuracy
Lower fidelity: Excel model, Higher fidelity: PRICE, or SEER,…
Create a Model Center Plug-in for the Cost Model
–
–
Generate a Case Study that specifies the MDO Inputs/Outputs
Wrap cost model (create cost model “plug-in”)
•
•
•
Models similar to SEER-H, PRICE (True Planning) – generally require vendor
support
Excel plug-ins (order-zero) can be created by the MDO team within Model Center
(with some training and experience)
Interface / link the Cost Model within the other Engineering Disciplines
(e.g. using the N^2 Diagram)
–
–
Populate & Test the Plug-in Model with simple test data
Populate the Plug-in with Real World problem & perform Design-ofExperiments (DOE)
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
True Planning Cost Model
- Select Hardware Model to become Plug-in
Major Hardware cost drivers include: Weight, Engineering Complexity,
Manufacturing Complexity, Quantity, Learning Curve, Reliability, Operational &
Support Costs
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
True Planning Cost Model
- Select Software Model to become Plug-in
The “COCOMO Family” of models is depicted below (Barry Boehm’s COnstructive COsting MOdel)
Major Software (COCOMO) cost drivers include: Sizing (new, adapted SLOC,
Auto-code), Cost Drivers (People, Process, Tools, Project Complexity)
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
Cost Models Are Linked to the MDAO (N^2) Models
(Including Cost, Propulsion, Structures, Mass Properties,…)
Configuration
Parameters
Propulsion
System
Structural
Loads &
Design
Wing
Design
Toolkit
Mass
Properties
Aerodynamic
Database
Linked CATIA Model
Optimizers
& Study
Drivers
Mission
Performance
RM & S
Cost Switch
(High, Low Fidelity)
Life Cycle
Cost
Engineering
Design,
Performance
Models
High Fidelity
Cost Models
True Planning
Cost Model
Cost Models are linked to the MDO, N^2 Diagram (Data Connectivity). User can
select between Higher Fidelity and Lower Fidelity Cost Model.
(“Lower” Fidelity Cost Models execute Faster than “Higher” Fidelity Models)
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
Populating the TruePlanning plug-in
Plug-ins are populated prior to performing a Design-of-Experiments. TruePlanning
has a relatively easy to use “Filter” Structure to populate the plug-in (variables)
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
Populated True Planning plug-in
True Planning
File (Instance)
The True Planning Object (“plug-in”) imported cost Variables must include
desired Inputs / Outputs. This data is available when performing (DOEs)
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
Generation of MDO Trade Space
-Design-of-Experiments (DOE) Summary
• Within Model Center, conduct DOE:
– Select Design & Response variables
– Select Ranges of Design variables (Low, High)
– Select the DOE sampling method
– Perform Simulations
• Analyze DOE Results
– Examine Trade Space Data
– Set Constraints to separate Feasible from Infeasible Solutions
– Focus on Affordable solutions, within best performance space
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
DOE Experiment Setup in Model Center
(Illustrative)
Design Variables (example): Max-Take-Off-Weight, Wing sweep, Wing Area,
Engine-scale, Percent of Payload used.
Response Variables: Cost, Empty Weight, Mission-Time, Range.
The Design trade space is a Combination of the Design Variables’ Ranges (Low,
High) Specified in the DOE Experiment.
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
DOE Sample Results with Objectives applied
Infeasible designs – e.g. Time-on-station Constraint setting
Empty
Weight
Development
Cost
Production
Cost
Development Cost
vs. Empty Weight
Production Cost vs.
Empty Weight
DOE Sample shows Feasible Designs Blue (best) to Red (worst), and infeasible
x
solutions
shown in Gray. (Infeasible designs, e.g.: defined as less than x hours
“Time-on-Station” , or Range requirement ,… using the Constraint setting
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
Cost Affordability in Design Objectives, Constraints
“Define Objectives” step
Minimize
Cost
(importance
ranking)
“Define Constraints” step
Cost
Variable(s)
Constraint
Cost
Objectives allow & depict ranking of designs by cost (Scatter Matrix).
Chart shows Objectives “Controls” set to Minimize cost (Development, Production, and Operations &
Constraints
are used to exclude Infeasible solutions (range, etc.)
Support)
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
DOE Results showing Cost, Variable
(Scatter) Relationships - Blue best designs, red worst designs
Rows:
MTOW
WingSweep
Wing-area
EngineScale
% P/L
EmptyWeight
CFL
Development Cost
vs. Empty Weight
MissionTime
Infeasible data points eliminated. Each Design Results can be Identified with “Design
Comparison chart”. Includes Design & Response (Cost) Variable data profiles.
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
Best Valued (KPP, Cost) Designs
(Example Data)
The top designs using Model Center’s “Define Objectives” (Cost Minimized) ,
and “define Constraints” (e.g. Mission Time Less than 10 Hours)
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
DOE Designs Ranked by LCC Cost, FOMs:
e.g. Top Set of Designs from an Affordability Perspective
Relative Cost, Constant
Year 2011, M$
(Example Data)
Designs Ranked by LCC Cost
03 16 104
69
77 28 43
74
65
54 07 57 89 102 46 19 119
25 138
13
52 26
11
1
68
2
34
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
Cost Ranking of Designs
Affordable Designs Can be Ranked, Identified from large DOE Design Sample. Least
Cost Design set can be compared (intersected) with Best Technical Design set.
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
Cost Models MDAO Interface
- Using Model Center (Phoenix Integration)
Cost Model part of N-Squared:
-Lower Fidelity Cost Model
-TruePlanning, COCOMO (higher fidelity)
- Scope: NRE, REC cost, Operations & Support (LCC)
Cost model major drivers:
-Hardware (Empty weight, Technical Complexity)
-Software (Software size, Complexity)
-Flight Test (Flight Test Points)
-Production (Manufacturing Complexity, Quantity,
Rate of Production, Learning curve)
N-Squared cost model interfaces:
-Mass properties (structure, propulsion, avionics)
-Sub-systems weight (and density)
Cost Model role in DOE:
Cost model output parameters part of Response
parameters in Design-of-Experiments (for each
observation)
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
Summary – Cost Model Evaluation
Criteria
MDAO environment compatibility
Cost models must have a (stable) “plug-in” to allow
translation of model inputs via Model Center to the cost
model.
Ability of cost model to perform DOEs (must create numeric
translation tables for non-numeric inputs). If no, are the
number translation tables user friendly?
The cost model needs to interface to the N^2 -particularly
the Mass Properties (MDAO inputs)
Cost models should be portable (MDAO lab, projects, etc.)
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.
Summary – Cost Model Compared
MDAO environment compatibility
Excel cost models have inflexible WBS
(WBS list changes require numerous
Industry cost model have flexible WBS “link edit” changes
Verbal scales need to be translated to
Integers. Interpretation of output can Descriptive inputs convertible to
be more complex
numeric input within Excel. No issue
Can perform up to 500- design (DOE Can perform up to 10,000+ design
designs)
(DOE designs)
Difficult to move from Concept design Facilitates movement from Concept to
to Preliminary design
Preliminary design
Excel readily incorporates interface
Requires a mass properties model
“Component” part of the Excel MDO
interface, e.g. using Excel
model
Useable for trade studies and bid /
proposal
Only useable for design trade studies
Approved for public release; distribution unlimited. NGAS case 15-0255 dated 2/19/15.