Medical Technology Enterprise Consortium

PROPOSERS CONFERENCESOLICITATION NUMBER: MTEC-18-04-INCAPACITATION PREDICTION FOR READINESS IN EXPEDITIONARY DOMAINS: AN INTEGRATED COMPUTATIONAL TOOL (I-PREDICT)

January 12, 2018

• Provide an overview of the requirement• Identify funding expectations• Understand the solicitation and selection process • Understand proposal requirements• Understand the submission process

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OBJECTIVES

CAUTION

• The MTEC-18-04-I-PREDICT Request for Project Proposal (RPP) and supplementary information found in the Proposal Preparation Guide (PPG) are the official sources of information regarding the active solicitation.

• If you act on information from any source other than theseofficial sources, it is at your risk.

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I-PREDICT OVERVIEW

• The period of performance is expected to start on March 1, 2018 (subject to change).

• A near-complete prototype must be ready for delivery to the Government by July 31, 2018.

• Awardees will have until September 30, 2018 to make final minor improvements to the prototype.

4

FUNDING PLAN

• The U.S. Government (USG) currently has available approximately $850,000 for Fiscal Year (FY) 18.

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MTEC-17-09 SCHEDULE

Release Solicitation December 21, 2017

Proposers Webinar January 12, 2018

Proposal Due Date January 19, 2018 (Noon EST)

Anticipated Award Date February, 2018 (tentative)

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PROPOSAL GUIDANCE DOCUMENTS

• MTEC RPP MTEC-18-04-I-PREDICT– Submission Deadlines

– Evaluation Criteria

• Proposal Preparation Guide (PPG)– Full Proposal Formats

• MTEC Base Agreement (Sample)– Must agree to abide by Terms and Conditions in Full Proposals

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RECENT REQUIREMENTS CHANGE

• The following revisions were made to 10 U.S. Code 2371b the Authority of the Department of Defense to carry out certain prototype projects: – (1) The Secretary of Defense shall ensure that no official of an

agency enters into a transaction (other than a contract, grant, or cooperative agreement) for a prototype project under the authority of this section unless one of the following conditions is met:

> (A) There is at least one nontraditional defense contractor or nonprofit research institution participating to a significant extent in the prototype project.

> (B) All significant participants in the transaction other than the Federal Government are small businesses (including small businesses participating in a program described under section 9 of the Small Business Act (15 U.S.C. 638)) or nontraditional defense contractors.

> (C) At least one third of the total cost of the prototype project is to be paid out of funds provided by parties to the transaction provided by sources other than the Federal Government.

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REQUIREMENTS

• There is a statutory requirement for 1/3 cost share on projects that do not include significant participation of a Nontraditional Defense Contractor (NDC) or a Nonprofit Research Institution

• Examples of significant contribution include:– Supplying new key technology or products– Accomplishing a significant amount of the effort– Use of unique skilled personnel, facilities and/or equipment– Causing a material reduction in the cost or schedule or increase in the

performance– Improvement in performance

• A NDC can be at the prime level, team members, subcontractors, lower tier vendors, or "intra-company" business units

• Must have a DUNS #• Warranties and Representations required with the full proposal

9See Attachment 2 of the PPG for additional details

NONTRADITIONAL DEFENSE CONTRACTORDEFINITION

The term Nontraditional Defense Contractor is a business unit that has not, for a period of at least one-year prior to the issue date of the MTEC Request for Project Proposals, entered into or performed on any contract or subcontract that is subject to full coverage under the cost accounting standards (CAS) prescribed pursuant to section 26 of the Office of Federal Procurement Policy Act (41 U.S.C. 422) and the regulations implementing such action.

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MTEC ROYALTY PAYMENT AGREEMENT/ ADDITIONALRESEARCH PROJECT AWARD ASSESSMENT

• MTEC members receiving MTEC funding agreement for research projects will be required to execute a MTEC Royalty Payment Agreement or pay an additional 2% assessment fee on the award.

• Available on the MTEC Members-only site.

• Submit a signed copy with the proposal.

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See page 41 of the MTEC PPG or Section 3.4 of the Consortium Member Agreement for additional details

CO-FUNDING OPPORTUNITIES

• As part of MTEC’s mission to incorporate philanthropic donations and other non-Government funds, MTEC frequently makes contact with private organizations that award agreements for research and operate in research areas that are aligned with those of MTEC.

• These private organizations (e.g., Bill and Melinda Gates Foundation) may be interested in reviewing proposals within their program areas, allowing for opportunities to attract supplemental funding sources.

• MTEC Staff will have access to your Technical Proposal for the purposes of engaging in outreach activities with these private organizations. MTEC Staff have signed Nondisclosure Agreements (NDAs) and Organizational Conflict of Interest (OCI) statements.

• If you choose not to allow MTEC Staff access, please indicate this decision on your proposal Cover Page, otherwise MTEC will understand that you are agreeing to this supplemental funding opportunity.

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GENERAL INSTRUCTIONS

• White papers are not required for this RPP.

• Offerors are advised to check the MTEC website periodically during the proposal preparation period for any changes as well as clarifications.

• The Technical Proposal and Cost Proposal must be submitted in 2 separate volumes following the format described in the Proposal Preparation Guide (PPG).

• The Technical Proposal and Cost Proposals shall remain valid for 180 days unless otherwise specified by the Offeror in the proposal.

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FULL PROPOSAL REQUIREMENTS

Offerors must submit the following:

• 1 signed Technical Proposal

• SOW and Milestone Payment Schedule in Word format submitted separately

• 1 signed Cost Proposal

• Cost Proposal Narrative (by task) and Cost Proposal (by task) Formats separate – (only requesting cost for task 1 and task 2 at this time)

• Signed Warranties and Representations

• Signed Royalty Payment Agreement or Additional Research Project Award Assessment document

14See page 16 of the MTEC PPG for additional details

FULL PROPOSAL COVER PAGE

• Technical and Cost Proposals must include a cover sheet that includes:

– Name and address of Offeror– Title of Proposal– Volume 1 Technical Proposal (OR Volume 2 Cost Proposal)– Statement: “This proposal is submitted pursuant to Request for Project

Proposals MTEC-18-04-I-PREDICT”– Offeror certifies that, if selected for award, the Offeror will abide by

the terms and conditions of the MTEC Base Agreement – Date of submission and signature of official authorized to obligate the

institution contractually– A proprietary data disclosure statement, when/if proprietary data is

included– Nontraditional Defense Contractor and/or Nonprofit Research

Institution %

15See page 17 of the MTEC PPG for additional details

TECHNICAL PROPOSAL REQUIREMENTS

• The Technical Proposal is limited to 30 pages • The Technical Proposal format shown below is mandatory:

– Cover Page (not in included in page limit)– MTEC Member Information Sheet (not included in page limit)– Table of Contents (not included in page limit)

– List of Figures and Tables (not included in page limit)– Executive Summary– Technical Approach

> Technology Objectives

> Management, Schedule and Resources

> Proposed Cost Share above Statutory Minimum

> Cost Realism

16See pages 19-33 of the MTEC PPG and

pages 21-22 of the MTEC RPP for additional details

TECHNICAL PROPOSAL REQUIREMENTS CON’T

– Progress

– Relevant Experience

– Effectiveness (Opportunity and Risk)

– Data Rights Assertions

– Technical Collaboration

– References/Bibliography (not included in page limit)

– Anticipated Regulatory and Commercialization Strategy

– Appendices

> Resumes of Key Personnel (not included in page limit)

> Statement of Work (not included in page limit)

> Letters of Support

17See pages 19-33 of the MTEC PPG and

pages 21-22 of the MTEC RPP for additional details

COST PROPOSAL REQUIREMENTS

To ensure Cost Proposals receive proper consideration, it is mandatory that the Cost Proposal include the following information:

• Section 1 – Cost Proposal Narrative

– Cover Page

– MTEC Member Organization Information Sheet

– Table of Contents

– Budget Narrative

– MTEC Royalty Payment Agreement or MTEC Additional Research Project Award Assessment

• Section 2 – Cost Proposal by Task Formats

– The Cost Proposal by Task Formats are mandatory

– These formats are available on the MTEC Members-Only site

18See pages 34-41 of the MTEC PPG for additional details

SELECTION

• As described in Section 3.3.2 of the PPG, the Consortium Manager will conduct a preliminary screening of received proposals to ensure compliance with the RPP requirements.

• One of the primary reasons for non-compliance and elimination during this initial screening is that the proposal does not offer significant Nontraditional Defense Contractor participation or cost share (see RPP Section 3).

• Following the preliminary screening, the Government sponsor will conduct an evaluation of all qualified proposals. The Source Selection Authority may:

– Select the proposal (or some portion of the proposal) for award

– Place the proposal in the Basket

– Reject the proposal

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PROPOSAL EVALUATION PROCESS

Offerors submitting the best value proposals that meet the following Factors and evaluation criteria will be selected for award negotiations (Evaluation factors are listed in descending order of importance with the weighting percentage in parenthesis):

1. Technical Approach (65%)

2. Cost/Price (25%)

3. Potential for Transition and Commercialization (10%)

As the Technical Approach and Cost/Price factors begin to reach equality in the technical evaluation and cost ratings, the Potential for Transition and Commercialization factor becomes more important in the trade off analysis.

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See pages 23-28 of the MTEC RPP for additional details

POST-AWARD

• The Award(s) will be issued and managed by ATI, MTEC’s Consortium Manager. Submission of quarterly reports and monthly invoices is required.

• Strategic oversight for the award(s) will be provided by the Office of Naval Research (ONR) Code 34 Warfighter Performance Department and its support team.

• It is expected that Awardees/Performers will engage in robust and frequent communication with ONR throughout the Period of Performance.

• Awardees/Performers will be expected to meet evolving requirements while leveraging agile best practices in model development and experimentation.

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FULL PROPOSAL SUBMISSION

• Proposals in response to this RPP, must be received by the date on the cover page of the RPP.

• Proposals received after the time and date specified will not be evaluated.

• MTEC will email receipt confirmations to Offerors upon submission of proposals.

• Offerors may submit proposal in advance of the deadline.

22See page 12 of the RPP for additional details

DISTRIBUTION STATEMENT A. Approved for public release. 23

I-PREDICTIncapacitation Prediction for Readiness in Expeditionary Domains: an Integrated Computational Tool

Office of Naval ResearchWarfighter Performance S&T Department

Timothy B. Bentley, Ph.D.

Distribution Statement A: Approved for Public Release DCN: 43-3514-18

DISTRIBUTION STATEMENT A. Approved for public release. 24

I-PREDICT & MTEC:Not your average BAA

MTEC (the Medical Technology Enterprise Consortium) is a biomedical technology consortium collaborating with multiple government agencies under a Other Transaction Agreement (OTA) with the U.S. Army Medical Research and Materiel Command (USAMRMC).

IPREDICT is currently exploring partnerships with other DoD organizations.

https://mtec-sc.org/about-us/

A Diverse Team, A Shared Goal

DISTRIBUTION STATEMENT A. Approved for public release. 25

S&T Problems Addressed

NAVSEA

NAVAIR

Marine Corps

Ergonomics

Injury Prevention

PPE Design

Ballistic and Blast Loading

Incapacitation Prediction

Guidelines for Seat Design

Acceleration and G-force

We can model the physics of

ballistic and blast events

We can model material properties of

PPE and PPE systems

We can model platforms

We can model the physics of acceleration and G-force

We cannot model the effect on the whole human

We can model the interaction of the

“human” with a platform using physics-based

models.

DISTRIBUTION STATEMENT A. Approved for public release. 26

A dynamic virtual ‘skin-in’ model of the warfighters (male and female) body based on biofidelicproperties of tissues and organs and response to injury

I-PREDICT: Digital twin of the warfighter

Entirely in silico, a computer model,

not a manikin

DISTRIBUTION STATEMENT A. Approved for public release. 27

Warfighters are subjected to unusual and extreme loads

The Warfighter =Soft Engineering System

Blast Acceleration

Vibration BluntNeed to test impact to warfighter body

DISTRIBUTION STATEMENT A. Approved for public release. 28

Digital Thread: Insult to Injury

BLAST

Vibration

Acceleration

Blunt

Models of Military Insults/Forces

Models of armor/ vehicle

Models of Target

Simple, Limited Injury Prediction:• Pass• Fail

Clay

Ballistic Gel

DISTRIBUTION STATEMENT A. Approved for public release. 29

Digital Thread: Insult to Injury

Models of Military Insults/Forces

Models of armor/ vehicle

Models of Target

Injury Prediction

Informed Injury Prediction: actionable and informative for:• Equipment design• Medical Decisions• Operational Limits

BLAST

Vibration

Acceleration

Blunt

DISTRIBUTION STATEMENT A. Approved for public release. 30

Injury Mechanisms of Interest

Focus will be on the injury mechanism(s) of greatest interest and use case:

ACCELERATION& BLAST

BLUNT

DISTRIBUTION STATEMENT A. Approved for public release. 31

• IPREDICT aims to accurately reflect different tissue properties of different body parts

• Outdated 44mm clay deformation standards

Not all body parts are created equal

44 mm

44 mm?

44 mm?

44 mm?

44 mm?

44 mm?

Clay?

Neither clay nor ballistic gel fit the bill

DISTRIBUTION STATEMENT A. Approved for public release. 32

I-PREDICT Model Addresses Human tissue, not Cadavers

• Cold• Stiff• Old• Fixed• Decayed• Wounded/Diseased• No vital forces present

• Warm• Flexible• Living• Natural• In tact• Healthy• Vital forces present

DISTRIBUTION STATEMENT A. Approved for public release. 33

Addresses multiple tissues as individual components with distinct biophysical properties and characteristics

I-PREDICT Software Tool

• Skin• Muscle• Bone• Circulation• Nervous System• Lymph System• Internal Organs

Dynamic& Static

DISTRIBUTION STATEMENT A. Approved for public release. 34

Many shapes, sizes, postures

I-PREDICT Software Tool

DISTRIBUTION STATEMENT A. Approved for public release. 35

Determining Incapacitation and Injury after insults

I-PREDICT Software Tool

Dynamic& Static

DISTRIBUTION STATEMENT A. Approved for public release. 36

A validated human computational model that will be relevant for the WarfighterCapable of assessing:

•PPE design impact on human body•PPE Protection•Injury•Incapacitation•Ergonomics•Live Fire Test and Evaluation•Training•Pain

I-PREDICT Software Tool

Mobility

Protection

DISTRIBUTION STATEMENT A. Approved for public release. 37

• Deliver a Technology Readiness Level (TRL) 6 whole human body computational modeling capability for military hazards– Establish biofidelic constitutive properties that better represent living human

tissue using novels experimental techniques (e.g., magnetic resonance elastography (in vivo) and high resolution optical elastography (ex vivo))

– Leverage existing models and data where appropriate

– Maintain program efficiency and agility as the requirements are updated throughout the period of performance

I-PREDICT Program Goals

DISTRIBUTION STATEMENT A. Approved for public release. 38

• I-PREDICT is planning to use a Technical Committee structure to leverage expertise across industry and academia while promoting communication among performers

Technical Committee Structure

DISTRIBUTION STATEMENT A. Approved for public release. 39

I-PREDICT Initial Scope

DISTRIBUTION STATEMENT A. Approved for public release. 40

• Predict injury and incapacitation as a result of behind armor blunt trauma to the thorax

I-PREDICT Initial Scope: Objectives

44 mmObjectives• Experimental assess constitutive properties of

biological tissues of the thorax that are more representative of the response of live human tissue in high-rate loading conditions

• Update an existing DoD owned computational model of the torso with increased biofidelity for high-rate loading conditions

DISTRIBUTION STATEMENT A. Approved for public release. 41

• Novel experimental techniques will provide highly biofidelic constitutive properties of human tissues

• Exemplar techniques:– Magnetic Resonance

Elastography– Optical Polarimetry-based

Elastography: viscoelastic material characterization

– In situ multiscale cavitation measurements

Updated Constitutive Properties

DISTRIBUTION STATEMENT A. Approved for public release. 42

• A Government owned computational model will be supplied to the performer(s)

• Model was developed to predict the “risk-of-significant” injury as a result of non-lethal weapons

• Biofidelity of the model will be improved via experimental data generated during the program and properties found from literature to represent live human tissue under high-rate loading.

Updated Computational Model

DISTRIBUTION STATEMENT A. Approved for public release. 43

I-PREDICT Initial Scope: Performers

• It is expected that a single award will be made to a qualified team to accomplish all tasks. However, MTEC may make multiple, individual awards to Offeror(s) to accomplish a subset(s) of the key tasks.

• If a single proposal is unable to sufficiently address the entire scope of this RPP’s technology objectives (outlined in section 5), several Offerors may be asked to work together in a collaborative manner.

• Teleconference will be held monthly to discuss performer progress

DISTRIBUTION STATEMENT A. Approved for public release. 44

• Expected Award Date: 01 March 2017

• Expected demo delivery: 30 August 2017

• End of Period of Performance: 30 Sept 2017

I-PREDICT Initial Scope: Timeline

DISTRIBUTION STATEMENT A. Approved for public release. 45

Overview of the Government Owned Computational Model

DISTRIBUTION STATEMENT A. Approved for public release. 46

• Originally developed for use in predicting “risk-of-significant” injury due to impact with non-lethal weapons

• Validated against:– Lower-speed impact cases by comparing model

predictions w. available low-speed frontal & side impact post-mortem human subject (PMHS) tests

– High-speed impact cases by comparing model predictions with PMHS impact tests using non-lethal projectiles

Overview

DISTRIBUTION STATEMENT A. Approved for public release. 47

• Geometry created using CT & higher-resolution images from the “Visible Man” project (Ackerman, 1991)– Resolution: in-plane = 1x1 mm2,

through-thickness = 1 mm– Human subject ≈ 95th percentile adult

male (90.3kg weight, 1.89m height)

• CT images processed to create parameterized geometries of rib cage and soft organs

• Surfaces smoothed, leading to generation of Initial Graphics Exchange Specification (IGES) surfaces Raw anatomy of rib cage,

torso walls, & soft organs reconstructed from CT

images

Geometry Extraction and Refinement

DISTRIBUTION STATEMENT A. Approved for public release. 48

Mesh Generation Overview

• Mesh template mapped onto non-uniform rational basis spline (NURBS) surfaces

• Meshes were refined to:– Improve element quality (as measured by the Jacobian)– Eliminate errors along the organ interfaces

Geometric modeling of raw anatomies produced smooth geometries that fit snugly side-by-side within the torso and are meshed with predominantly hexahedral elements

DISTRIBUTION STATEMENT A. Approved for public release. 49

• Rib cage model consists of ribs, cartilage, spin, & sternum– Developed by Niu & Shen (2007)– Specialized method was created to model the ribs and cartilage

to allow for both accurate load carrying and consistent contact treatment

• Rib geometry:– Reconstructed from Visible Man CT scans by iteratively

computing the centerline of the rib– Elliptical cross (x)-sections of varying size & orientation were fit

to the x-sections boundaries estimated from CT scans– Resultant geometry provided smooth volumes that form the

basis of the FE geometry

Rib Cage Model

DISTRIBUTION STATEMENT A. Approved for public release. 50

FE model of rib cage treats rib as inhomogeneous composite beam/shell structure

Rib Cage Model

• Beam elements (BEs) used along the rib centerline

• Shell elements (SEs) enclose BEs for accurate contact calculations

EIx

EIy

EAGJ

DISTRIBUTION STATEMENT A. Approved for public release. 51

• Spine:– Represented by a series of linear BEs, each representing a

motion segment (MS) with nodes at the vertebral body centroids

– Additional BEs added to transfer the forces & moments to the MSs through the vertebral processes and the rib attachment points; properties determined from geometry and approximate stiffness

• Sternum:– Geometry extracted w. same methods as ribs, other

components– Homogeneous solid meshed with hexahedral elements

• Costovertebral & sternocostal joints modeled as short beams

Rib Cage Model

DISTRIBUTION STATEMENT A. Approved for public release. 52

Material Model Assignments

• Biological materials have responses that can be dependent upon many factors such as:– Strain-rate– Strain history– Natural variability within sex and age range

• Material models and associated properties for the torso FEM were selected based on a literature review of empirically correlated material properties

• Nine types of tissue were modeled within the torso FEM:• Lungs• Heart• Spleen

• Liver• Abdomen• Diaphragm

• Stomach• Skin• Muscle

DISTRIBUTION STATEMENT A. Approved for public release. 53

Stomach, Spleen, and Liver Material Models

• Modeled as hyperelastic rubber materials

• Viscoelasticity models use a shear stress relaxation function represented by up to 6 terms of Prony’s series as:

where 𝐺𝐺𝑖𝑖 are shear moduli and 𝛽𝛽𝑖𝑖 are decaying constants

• βi obtained by fitting available relaxation data & maintaining a nearly constant hysteresis over the frequency ranges of interest

• LS-Dyna generated load curves from test data collected by Brown (2005)

– Stomach reduced to elastic model w. approximated elastic (Young’s) modulus, E = 500 kPa

– Poisson’s ratio for all organs, ν = 0.45

( )6

1

iti

ig t G e β−

=

=∑

DISTRIBUTION STATEMENT A. Approved for public release. 54

Lung Material Model

• Challenge due to varying amounts of tissue, air, and water

• Two predominant types of models used in literature:– Hyper-viscoelasticity model– Hydrodynamic model

• Latter selected for computational efficiency– Shear modulus = 733 Pa (Masiallo, 1997)– Lung density = 250 kg/m3 (based on CT images)

• A layer of 1 mm-thick shell elements coat the exterior faces of the lung to provide improved numerical stability

• Exterior SE layer uses a viscoelastic material with:– Bulk modulus, K = 1 GPa– Density, ρ = 1000 kg/m3

– Viscoelastic parameters:• Shear relaxation modulus, G = 3 MPa• Shear decay constant, β = 50

DISTRIBUTION STATEMENT A. Approved for public release. 55

• Internal pressure neglected by model – include equation-of-state:

where 𝜇𝜇 = ⁄𝜌𝜌 𝜌𝜌0 − 1, and P0, P1 are constants (lung pressure measured relative to ambient)

• Estimate P0, P1 via post-mortem human subject (PMHS) tests:– 4 pressure sensors inserted into tissue (3 on impact side, 1 on opp. side)– Impacted modified XM1052 round into abdomen of test subject at 95 m/s– Good agreement for P0 = 100 kPa, P1 = 800 kPa

20 1P P Pµ µ= +

Comparison between test data & FEM on PMHS for pressure in the right upper lung – similar fits for right lower lung & right lower lateral lung

Lung Material Model

DISTRIBUTION STATEMENT A. Approved for public release. 56

Heart Material Model

• LS-Dyna heart material model:

– Function of strain energy

– Developed by Gucciione & McCulloch (1991)

• Numerical parameters taken from Deng & Chang (2000)

– C = 1.085 kPa

– b1 = 24.26

– b2 = 40.52

– b3 = 1.63

DISTRIBUTION STATEMENT A. Approved for public release. 57

Rib Cage Material Model

• Assume bones behave as linearly elastic isotropic material

• Material properties obtained directly from CT images:

– CT number of each pixel used to determine bone density:𝜌𝜌eff = 𝐴𝐴 𝐻𝐻𝐻𝐻 + 1000 ⁄kg m3

where ρeff is the effective density, HU is the Houndsfield unit (i.e., the CT number), and A is a correction factor dependent on CT machine (=0.523 (Rho, 1995), =0.464 (Taylor, 2002))

– Elastic modulus then estimated from ρeff using literature equations:• General bone (Carter & Hayes, 1977):

E = 2875ρ3 (MPa) (ρ≤2.0g/cm3)• Cortical & trabecular bones (Goldstein, 1991):

𝐸𝐸 = � 1352𝜌𝜌1.48 MPa 0 ≤ 𝜌𝜌 < 1.4 ⁄g cm3

34623𝜌𝜌 − 46246 MPa 1.4 ≤ 𝜌𝜌 < 2.0 ⁄g cm3

DISTRIBUTION STATEMENT A. Approved for public release. 58

• Ribs:– Consist of mixture of hard cortical & soft trabecular bones– Goldstein eq. applicable to both cortical & trabecular bones– Each rib subdivided into 50-150 BEs

• Each w. own ρeff and E calculated from CT scan images

• Accompanying SEs tied to each BE share the same material properties– Mass & stiffness of BEs reduced to compensate for additional rigidity &

inertia from shell elements by adjusting beam’s x-sectional parameters (e.g., moment of inertia, x-sectional area)

• Sternum & spine: linear elastic material model– Sternum ρeff calculated w. CT image data, =1600 kg/m3, elastic

modulus, E=10 GPa, Poisson’s ratio, ν=0.4– Spine: ρeff =1700 kg/m3, E = 15 GPa, ν = 0.4

– Spine BEs connect the right & left ribs in the back of the torso

Rib Cage Material Model

DISTRIBUTION STATEMENT A. Approved for public release. 59

Skin and Muscle Material Models

• Skin & muscles share characteristics with polymeric materials, including:– Rubbery – due to strands of collagen chained together (Fung, 1993)– Viscoelastic behavior

• Arruda-Boyce model (in LS-Dyna) captures both• Material property values taken from Eisler (2004)

Part ρ(kg/m3)

K(GPa)

G(kPa)

Gi(kPa)

βi(1/s)

Skin 1000 2.0 30 30; 120; 360; 480; 688; 1200

1e3; 1; 0.1; 0.01; 1.0e-3; 1.0e-4Muscle 1000 2.5 30

DISTRIBUTION STATEMENT A. Approved for public release. 60

Interface Definitions

• Tied interfaces prohibit penetration & sliding

– Defined among skin, muscles, diaphragm, and rib cage

• Contacting surfaces permit sliding

– Defined between:

• Rib cage & organs

• Diaphragm & organs

• Among thoracic & abdominal organs

QUESTIONS AND ANSWERS

• Q&A submitted prior and during the call reviewed now (to the maximum extent practical).

• Q&A will be posted to the MTEC Members-Only site.

• Submit any other questions to:

– Questions concerning contractual, cost or pricing related to this RPP should be directed to the MTEC Contracts Manager, Ms. Lisa Fisher, lisa.fisher@ati.org

– Technical related questions should be directed to the MTEC Director of Research, Dr. Lauren Palestrini, Ph.D., lauren.palestrini@officer.mtec-sc.org

– Questions concerning membership should be directed to Ms. Stacey Lindbergh, MTEC Executive Director., execdirect@officer.mtec-sc.org

– All other questions should be directed to Ms. Kathy Zolman, MTEC Program Manager, kathy.zolman@ati.org

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