PLM World ‘06

Premium Partners:

Development of Space Exploration Technologies Through Integrated Design

and Analysis

Presented by:

Lisa Saam, ATA Engineering, Inc.

David Bodkin, Orbital Sciences Corp.

Lisa Saam ATA Engineering, Inc. May 2006 2

Work Presented is Result of Many Contributions, Most Notably…

Orbital Sciences Corporation

• Ken Bocam

• David Bodkin

• Jim Duffy

ATA Engineering, Inc.

• Ken Ferguson

• Scott Miskovish

• Lisa Saam

• Michael Yang

Lisa Saam ATA Engineering, Inc. May 2006 3

Presentation Outline

� Company background

� Project background & exploration architecture

� Analysis-driven design approach

� Crew Module

� Lunar Lander

� Lunar Habitat Module

Lisa Saam ATA Engineering, Inc. May 2006 4

ATA Has Provided High-Value Mechanical Design, Analysis & Test Services Since 1977

� 1977: SDRC opened western region services office in San Diego

� 2000: ATA Engineering, Inc. was formed as an employee-owned

company through the purchase of all assets and contractual

obligations of the Advanced Test and Analysis group of SDRC

Lisa Saam ATA Engineering, Inc. May 2006 5

Orbital Pioneers New Classes of Rockets, Satellites & Other Space-Based Technologies

� Founded in 1982 with the goal of making space technology more affordable, accessible and useful to millions of people on Earth.

� World's leading developer and manufacturer of smaller, more affordable space and rocket systems.

� Major Business Areas� Space Launch Vehicles

� Missile Defense Systems

� Satellites and Related Systems

� Advanced Space Systems

� Space Technical Services

� Transportation Management Systems

� Major Operations: Virginia, Arizona, Maryland, California

Lisa Saam ATA Engineering, Inc. May 2006 6

Orbital Sciences Awarded NASA Contracts to Support Country’s Space Exploration Vision

� Principal objective of Concept Exploration & Refinement

(CE&R) program:

� Support NASA in its development of the Vision for Space

Exploration

� Support associated scientific, economic, and security

objectives

� Develop initial concept for lunar exploration and crew return

vehicle (CEV) development plan and demonstration objectives

� Orbital Sciences’ goal:

� Define a safe, affordable, and low risk exploration architecture

and related development plan to support the Space

Exploration Vision

Lisa Saam ATA Engineering, Inc. May 2006 7

LEO

Lunar

Orbit

Lunar

Surface

Earth

First Stay:

14 days minimum

28 days goal

Orbital’s Architecture for Lunar Operations: Earth to Moon Phase

Lisa Saam ATA Engineering, Inc. May 2006 8

Orbital’s Architecture for Lunar Operations: Moon to Earth Phase

LEO

Lunar

Orbit

Lunar

Surface

Earth

Lisa Saam ATA Engineering, Inc. May 2006 9

Analysis-Driven Design Used to Define Conceptual Designs for Architecture Elements

Crew

Module

Lunar Lander

Crew Module

Lunar Lander

Airlock for

Lunar

Habitats

Lunar Habitat

Module

Ability to rapidly transition between

CAD and CAE allowed multiple

design iterations to be performed –

leading directly to the project’s

success.

Lisa Saam ATA Engineering, Inc. May 2006 10

Crew Module Case Study to Demonstrate Structural Sizing Process

CAD

Material Selection

CAE

Design Iterations

Mass Estimate

25,566 lbm

Lisa Saam ATA Engineering, Inc. May 2006 11

Defined Optimization Parameters to Achieve Positive Margins of Safety while Minimizing Mass

� Boundary conditions & subcases (11 cases total)

� On Pad, Max Q, Max Nx, Escape Entry, Parachute, Impact, Pad Abort, Max Q Abort, Max G Abort, Overpressure (x2)

� Design variables

� Shell thickness, beam cross-section dimensions, etc.

� Initial value, lower bound, upper bound

� Design constraints: Material allowables

� Design objective � Minimize mass

� Analyses performed with both I-deas and NX Nastran

� In general, found better convergence with NX Nastran

Stress Location Stress Limit

vonMises Stress for shells

u

u

y

cy

y

ty

FSFSFSσσσ,,min

Compressive stress in beams

y

cy

FS

σ

Tensile stress in beams

u

u

y

ty

FSFSσσ,min

Lisa Saam ATA Engineering, Inc. May 2006 12

Design Optimization Shell Results

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Hea

tshield 1

Hea

tshield 2

Hea

tshield 3

Bulkh

ead

Cab

in fw

dCab

in aft

Cab

in to

pCab

in sidesTu

nnel

Cen

terbod

yNos

e pa

nel

Nos

e sh

roud

Nos

e sh

elf

Cab

in-O

ML

Hatch

-OML

Thickness [in]

Original

Optimized

Lisa Saam ATA Engineering, Inc. May 2006 13

Design Optimization Beam Results

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

CFT CAT CFS CMS CAS CCS CBF CBA CC

Width [in.]

Original Optimized

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

CFT CAT CFS CMS CAS CCS CBF CBA CC

Thickness [in.]

Original Optimized

Width

Thickness

• Beam height also optimized

but not shown

w

h

t

Lisa Saam ATA Engineering, Inc. May 2006 14

Checks Always Performed on Optimization Results

� Run load cases with new design values to check

stresses, displacements, frequencies, etc.

� Change initial values of design variable and rerun

optimization to see if similar result is achieved

� Rerun optimization with new design values to see if any

further optimization can be achieved

� Adjust new design values to standard shapes and sizes

Optimized mass = 25,566 lbm

Placeholder mass = 28,693 lbm

�Weight savings = 3,127 lbm

Lisa Saam ATA Engineering, Inc. May 2006 15

Crew

Module

Lunar Lander

Airlock for

Lunar

Habitats

Lunar Habitat

Module

Analysis-Driven Design Used to Define Conceptual Design for Lunar Lander

Lunar Lander

Crew Module

Lisa Saam ATA Engineering, Inc. May 2006 16

Lunar Lander Has Common Base Structure for Human and Cargo Missions

Lunar Lander base structure

Tank and engine layout

• Reusable, one-stage vehicle

• Cargo missions autonomous

• Human lander holds four

astronauts with 7 days of life

support

Cargo Lunar Lander

Human Lunar Lander

Lisa Saam ATA Engineering, Inc. May 2006 17

Mass Estimate & Conceptual Design Developed through Design Optimization

Member Dimension Value [in.]

FS Thkns 0.044

Core Thkns 2.000

FS Thkns 0.044

Core Thkns 2.000

Width 6.880

Thkns 0.040

Height 6.875

Width 4.916

Thkns 0.046

Height 4.916

Width 4.916

Thkns 0.045

Height 4.916

Width 4.911

Thkns 0.062

Height 4.907

Width 6.892

Thkns 0.069

Height 6.897

Width 4.916

Thkns 0.046

Height 4.916

Thrust Structure

Axial Stringer

Top Ring

Bottom Ring

Top Panel

Bottom Panel

Core

Middle Ring

Optimized mass = 4,694 lbm

Driving load case

is earth ascent

Lisa Saam ATA Engineering, Inc. May 2006 18

Analysis-Driven Design Used to Define Conceptual Design for Lunar Habitat Module

Crew

Module

Lunar Lander

Airlock for

Lunar

Habitats

Lunar Habitat

Module

Lunar Lander

Crew Module

Lisa Saam ATA Engineering, Inc. May 2006 19

Lunar Habitat Consists of Multiple Habitat Modules

� Designed for low gravity rather than zero gravity

� Special considerations such as internal floor area/unit mass, height of airlocks, height of floor relative to airlock

� Provides crew habitation, scientific laboratories & protection from environmental hazards

� Supports 4 crew members on lunar surface for >6 months

Lisa Saam ATA Engineering, Inc. May 2006 20

Study to Determine Optimal Pressure Vessel Shape of Lunar Habitat Module

� Used CAD & CAE to evaluate:

� Total volume

� Livable volume

� Pressure vessel mass

� Floor & ceiling mass

� Total mass/volume

� Floor area

� Ceiling area

� Hatch height

Lisa Saam ATA Engineering, Inc. May 2006 21

In Conclusion…

Ability to rapidly transition between

CAD and CAE allowed multiple

design iterations to be performed –

leading directly to the project’s

success.

PLM World ‘06

Premium Partners:

Development of Space Exploration Technologies Through Integrated Design

and Analysis

Presented by:

Lisa Saam, ATA Engineering, Inc.

David Bodkin, Orbital Sciences Corp.