Research

Mechanics Education

I am interested in discovering how students learn in introductory mechanics courses (statics, dynamics, and mechanics of materials) and finding ways to enhance their learning in those courses.

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.


gray@psu.edu © Gary L. Gray 2013