• Orbital mechanics, astrodynamics, and spacecraft guidance, navigation, and control
• Spacecraft attitude and relative motion dynamics and control
• Manifold-based libration point transfers
• Orbital dynamics and hovering control in small body environments
• Stability, control, and estimation in time-periodic, time-delayed, stochastic, and fractional systems
• Nonlinear dynamics, bifurcations, chaos, and chaos control
• Hamiltonian systems and canonical perturbation theory
• Nonlinear vibrations, order reduction of nonlinear and nonsmooth structural systems