Expert Details

Nastran Analysis, Linear & Non-linear Statics, Dynamics & Thermal Analysis

ID: 730343 Florida, USA

Expert has applied his aerospace engineering background of 41 years experience, with major responsibility for providing Computer Aided Engineering (CAE) Nastran Analysis, Programming and consultation using Finite Element Analysis (FEA) technique, in the fields of Structural, Mechanical and Thermal systems analysis (statics and dynamics), with emphasis on dynamics.

Expert's job history includes over 37 years experience in Structural Dynamics, Random Vibration, Shock and Response Spectrum Analysis and Dynamic Systems Modeling and Simulation in support of NASA projects (Apollo, Space Shuttle, X-33, Titan IIIC, Atlas V and Ares 1 Space Programs) at the Kennedy Space Center. He also has 4 years experience on analysis of heavy construction and mining equipment performing structural/mechanical stress analysis and dynamic system modeling.

He is one of sixteen members of the MSC/NASTRAN Select Users Advisory Board (1993).

He has extensive FEA skills include the following:
- Linear and Nonlinear Statics Analyses
- Modal and Complex Modal Analyses
- Linear and Nonlinear Dynamic Analyses
- Frequency and Random Response Analyses
- Shock Spectra (Response Spectrum) Analysis
- Steady State and Transient Thermal Analyses
- Linear and Nonlinear Buckling Analyses
- Fracture Mechanics Analysis

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Education

Year	Degree	Subject	Institution
Year: 1968	Degree: BS	Subject: Aeronautical and Astronautical Engineering	Institution: University of Illinois

Work History

Years	Employer	Title	Department
Years: 1986 to 2011	Employer: United Space Alliance - Lockheed Martin Space Operations	Title: Engineering Staff VI	Department: Technical Analysis
Responsibilities: Expert provided Computer Aided Engineering (CAE) Analysis, using Finite Element Analysis (FEA) technique, in the fields of Structural and Mechanical systems analysis (statics and dynamics) and thermal analysis (steady state and transient) of structural, mechanical, and piping systems for Space Shuttle ground support and test equipment and flight equipment. He developed computer programs to provide engineering analysis for most of the major structural, mechanical, and piping systems used by the Space Shuttle at Kennedy Space Center, along with some programs related to Space Shuttle Payloads such as the Hubble Space Telescope and Tracking and Data Relay Satellite System. Engineering Lead providing education, direction, and advice on FEA. He provided test/analysis correlation of data to solve system problems. He recommended purchases of computer hardware and software for engineering work. He Wrote specifications (Request for Proposal) for computer hardware and software requirements in the procurement of CAE, FEA, and Computer Aided Design (CAD) computer systems. He also provided Engineering Analysis for ground support and flight systems on the X-33 program, ground support systems on the Apollo/Soyuz and Atlas V programs, rollout/pad stay analysis for Ares I-X (Constellation program) and dynamics and loads analysis of Ares I flight hardware. He is experience in Aerospace structures analysis, including Nastran models and connection analysis.
Years	Employer	Title	Department
Years: 1974 to 1986	Employer: Planning Research Corporation	Title: Principal Engineer	Department: Analytical Staff
Responsibilities: Karls' job responsibilities is similar to the United Space Alliance/Lockheed Martin experience. He was Lead Engineer in charge of 8 people that provided Nastran CAE analysis of Space Shuttle ground support systems and test equipment.
Years	Employer	Title	Department
Years: 1969 to 1973	Employer: Westinghouse Air Brake Company (WABCO)	Title: Engineer	Department: Test/Analysis Staff
Responsibilities: Expert provided Design Engineering for heavy construction and mining equipment. He provided CAE analysis. He also was a Test Engineer providing test setup and analysis of test data. He was an Engineering Analyst providing computer programs for structural/mechanical systems analysis.

Additional Experience

Expert Witness Experience
Expert developed and integrated models for rollout and launch pad stay Nastran analysis of the AresI-X rocket at Kennedy Space Center. The following are quotes from Ames Research Center for a review of the Nastran models and model results: KSC is preparing to launch the first of the Constellation vehicles, Ares 1-X, by making extensive use of heritage hardware from STS for ground operations. This will include use of the existing crawler-transporter (CT), an existing mobile launch platform (MLP), existing mount mechanisms (MM) and the existing fixed service structure (FSS) at pad 39B with a new vehicle stabilization system (VSS) that is yet to be constructed. As part of the modeling and simulation effort for the ground support operations of this test flight, the subject report has been prepared by United Space Alliance. It includes analysis of the NASTRAN finite element models depicting the hardware mentioned above, integrated to an existing vehicle model (IVM13) that was assembled from elemental models originally provided by ATK, Glenn Research Center and Langley Research Center. The elemental CT and MLP models are existing certified NASA critical math models. Modeling of the RSS/FSS and VSS structures was performed by USA. The technical work was found to be very thorough and detailed. In particular, the finite element modeling was excellent. The fidelity achieved by integrating several existing models provided very good results for internal loads and external reactions. These loads form the basis of input to other detailed stress reports that show positive margin for use of the heritage hardware. Mode shapes, transient responses and frequency/random response were achieved with very good resolution. Documents that were reviewed in detail included all of the program and agency wind loading criteria (NEDD, DSNE, 1001) as well as the Reference 2 verification of the Ares 1-X IVM vehicle models and the Reference 3 Technical Analysis Report. In addition to this, several of the NASTRAN finite element models used in this analysis were independently run with unit loadings (SOL 101-static analysis) and separately for mode frequencies and shapes (SOL 103-modal analysis). The results of these model validation efforts are noted in Appendix A. Appendix A comments:In order to validate the two integrated models, check runs for both statics and modes were made. Solution 101 was performed on the IVM13-ML-CT model using 1 kip unit loads at the tip of the vehicle in both the north and south direction. For the IVM13-FSS-VSS model, a Solution 101 case was run using the design wind loads from the east. For both models, Solution 103 (normal modes) was run and the primary mode shapes were compared to previously validated models. Weight of the models was found to be within 2% of the values shown in Table 4-8, 4-9 and 4-10. All weights were checked against source data provided in Reference 1. Mode frequencies shown in Appendices A, B and C were found to be within 1% of the values listed in the appropriate tables, with correspondingly appropriate mode shapes. Moments of inertia and principle axis were checked for each elemental model (CT, MLP, IVM) and found to be proper as to location and magnitude. Structural drawings of the CT and MLP were checked against section properties at selected locations in the elemental models and no discrepancies were found. All RBE elements were studied for connectivity issues and none were found. CONM2 mass values were spot checked and found to be reasonable.

Expert Witness Experience

Expert developed and integrated models for rollout and launch pad stay Nastran analysis of the AresI-X rocket at Kennedy Space Center.

The following are quotes from Ames Research Center for a review of the Nastran models and model results:

KSC is preparing to launch the first of the Constellation vehicles, Ares 1-X, by making extensive use of heritage hardware from STS for ground operations. This will include use of the existing crawler-transporter (CT), an existing mobile launch platform (MLP), existing mount mechanisms (MM) and the existing fixed service structure (FSS) at pad 39B with a new vehicle stabilization system (VSS) that is yet to be constructed. As part of the modeling and simulation effort for the ground support operations of this test flight, the subject report has been prepared by United Space Alliance. It includes analysis of the NASTRAN finite element models depicting the hardware mentioned above, integrated to an existing vehicle model (IVM13) that was assembled from elemental models originally provided by ATK, Glenn Research Center and Langley Research Center. The elemental CT and MLP models are existing certified NASA critical math models. Modeling of the RSS/FSS and VSS structures was performed by USA.

The technical work was found to be very thorough and detailed. In particular, the finite element modeling was excellent. The fidelity achieved by integrating several existing models provided very good results for internal loads and external reactions. These loads form the basis of input to other detailed stress reports that show positive margin for use of the heritage hardware. Mode shapes, transient responses and frequency/random response were achieved with very good resolution. Documents that were reviewed in detail included all of the program and agency wind loading criteria (NEDD, DSNE, 1001) as well as the Reference 2 verification of the Ares 1-X IVM vehicle models and the Reference 3 Technical Analysis Report. In addition to this, several of the NASTRAN finite element models used in this analysis were independently run with unit loadings (SOL 101-static analysis) and separately for mode frequencies and shapes (SOL 103-modal analysis). The results of these model validation efforts are noted in Appendix A.

Appendix A comments:In order to validate the two integrated models, check runs for both statics and modes were made. Solution 101 was performed on the IVM13-ML-CT model using 1 kip unit loads at the tip of the vehicle in both the north and south direction. For the IVM13-FSS-VSS model, a Solution 101 case was run using the design wind loads from the east. For both models, Solution 103 (normal modes) was run and the primary mode shapes were compared to previously validated models. Weight of the models was found to be within 2% of the values shown in Table 4-8, 4-9 and 4-10. All weights were checked against source data provided in Reference 1. Mode frequencies shown in Appendices A, B and C were found to be within 1% of the values listed in the appropriate tables, with correspondingly appropriate mode shapes. Moments of inertia and principle axis were checked for each elemental model (CT, MLP, IVM) and found to be proper as to location and magnitude. Structural drawings of the CT and MLP were checked against section properties at selected locations in the elemental models and no discrepancies were found. All RBE elements were studied for connectivity issues and none were found. CONM2 mass values were spot checked and found to be reasonable.

Career Accomplishments

Associations / Societies
American Institute of Aeronautics and Astronautics (AIAA), Senior Member. American Institute of Steel Construction (AISC).

Awards / Recognition
One of sixteen members of MSC/NASTRAN Select Users Advisory Board (1993). Hold 3 US Patents. Authored or co-authored over 30 publications Three NASA Public Service Group Achievement Awards. Lockheed’s Andy Petro Engineering Excellence Award. NASA Space Shuttle Launch Honoree Award.

Publications and Patents Summary
He has over 30 publications and three patents.

Fields of Expertise

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Expert Details

Nastran Analysis, Linear & Non-linear Statics, Dynamics & Thermal Analysis

Education

Work History

Responsibilities:

Responsibilities:

Responsibilities:

Additional Experience

Career Accomplishments

Fields of Expertise