Research Interests & Professional Affiliations

Some of My Current Research Interests

Engineering the Nanoscale Morphology of Thin Films: a Molecular Dynamics Approach

I am working with Professor Francesco Costanzo on this project. The project's objectives are:

1. to use molecular dynamics (MD) to identify the relations between thin film (TF) deposition parameters and the resulting morphology of low mobility columnar thin films (CTFs); and

2. to translate the outcome of MD simulations into corresponding mechanical properties including residual stresses, elastic moduli and substrate/film interfacial strength.

We currently have one graduate student (Pedro Andia) working on this project and we are actively seeking at least one or two additional students.

Nonlinear Spacecraft Attitude Dynamics

We are analytically and numerically studying nonlinear effects in satellite attitude dynamics. Our numerical work has involved the integration of the equations of motion for damped, nonautonomously perturbed single-body spacecraft. We are computing trajectories in phase space, Lyapunov exponents, fast Fourier transforms, stable and unstable manifolds, Poincare maps, bifurcation diagrams, and cell-maps for these systems. Analytically, we are applying Melnikov's method and perturbation methods such as averaging to these systems to obtain bounds on nonlinear behavior in the system's parameter space. In addition, we are extending our analytical and numerical results to more complex spacecraft systems such as dual-spinners and spacecraft with continuous flexibilities. I began this work as a Ph.D. student at the University of Wisconsin and continued it after coming to Penn State. I have graduated one Ph.D. student (Rick Campbell) on this work and I currently have three graduate students continuing this work:

• Andy Miller (M.S. student); studying fundamental aspects of the dynamics of spacecraft and those factors which influence the onset of nonlinear behavior and chaos in different classe of spacecraft;

Andy Miller working at one of our Macs.	Our little cluster of RS/6000 UNIX workstations.

Click on the image to see a larger version.

Improved Electrical Connectors Using Shape Memory Alloys

I am working with Professor Suzanne Mohney on an interdisciplinary project sponsored by Ford Motor Company to improve electrical connectors in the near-engine, elevated temperature environment. This project involves:

• The understanding and the implementation of SMAs in electrical connectors through the study of their long-term stability, constrained recovery characteristics, and mitigation of fretting corrosion as the connector undergoes vibration. This aspect of the project is being carried out by myself, Igor Kulisic (M.S. student), and Tom Yurick (M.S. student), and Prof. Mohney.

• The understanding and improvement of coatings used on the connectors Prof. Mohney is working on this with a variety of undergraduate students.

Igor Kulisic is testing electrical connectors at elevated temperatures under vibration.	Igor Kulisic and Tom Yurick, Jr. measure the insertion/removal forces of connectors.	Tom Yurick, Jr. is testing electrical connectors at elevated temperatures under vibration.	A clever device to measure the insertion/removal forces of connectors.

Click on the image to see a larger version.

Interactive Dynamics/Mechanics

I am working with Prof. Francesco Costanzo and a number of undergraduate students (Ben Conaway, Molly Riley, Chris Watterson) to develop a "studio"-based learning environment for undergraduate dynamics. This environment, which we call The Interactive Classroom, contains essentially all of the ingredients the ABET 2000 criteria deems important for a well-educated engineer. In particular, the dynamics version of this Interactive Classroom, called Interactive Dynamics, promotes the application of mathematics and science to engineering, the application of advanced mathematics in engineering problems, the integration of contemporary analytical, computational and experimental practices (these describe a typical activity), teamwork (students work in teams), and effective communication (through reports). We are using outcomes-based assessment (with a guidance and assistance from personnel in Engineering Instructional Services) to measure student performance in the following areas:

• conceptual and quantitative understanding of fundamental and important topics in undergraduate dynamics, including the ability to solve problems in these areas;

• ability to write a good technical report;

• proficiency with modern computer tools such as spreadsheets and web browsers;

• academic topics not usually associated with dynamics courses such as knowledge of numerical analysis, data analysis, and error analysis.

The eventual goal of this project is to demonstrate the success of the Interactive Classroom concept and then to implement it in all sections of undergraduate dynamics as well as statics and strength of materials. This project is partially funded through a grant from the GE Fund.

A Few Nonlinear Dynamics Sites

sci.nonlinear FAQ

UK Nonlinear News

UCSD Institute for Nonlinear Science

Chaos Group at the University of Maryland

Los Alamos Center for Nonlinear Studies

Nonlinear Science E-Print Archive

Nonlinear Dynamics Who's Who. This isn't a "who's who" in the traditional sense since all you need to do is fill out a form, but it can be useful for locating people.

Caltech Control and Dynamical Systems Department

Chaos Analysis Software

Nonlinear Science Today & the Journal of Nonlinear Science

Professional Affiliations

American Society of Mechanical Engineers (ASME)

American Institute of Aeronautics and Astronautics (AIAA)

American Astronautical Society (AAS)

Society of Engineering Science (SES)

Penn State Center for Acoustics and Vibration (CAV)

American Society for Engineering Education (ASEE)

Some of My Publications