Lyapunov-based On-off Control: Current Research on Satellites Differential Drag Applications

Monday, February 28, 2011 - 11:00am - 1:00pm EST

  • Location:Dibner Building, LC 433
    Five MetroTech Center, Brooklyn, NY

Smart Materials and Systems Seminar Series

Professor Riccardo Bevilacqua

Rensselaer Polytechnic Institute, Troy, NY

Abstract

This seminar presents the on-going research on devising a Lyapunov-based control strategies to perform spacecraft rendezvous maneuvers exploiting differential drag forces. The approach is envisioned to control the nonlinear dynamics of spacecraft relative motion using on-off control, by introducing two linear models: a first one to generate a guidance trajectory, based on linearized equations of spacecraft relative motion, and a second model to guarantee global asymptotical stability of the tracking error. The second linear model is a mathematical artifact required by the Lyapunov approach to be stable. A Lyapunov-based control law is being designed to force the spacecraft to track the second linear model, which, in turn, follows the trajectory of the first linear model.

Differential drag is an alternative method for generating control forces at low Earth orbits by varying the aerodynamic drag experienced by different spacecraft. The variation in the drag can be induced by closing or opening flat panels attached to the spacecraft. Efficient and autonomous spacecraft rendezvous maneuvering willhave a decisive role in future space missions. To increase the efficiency and economic viability of such maneuvers, propellant consumption must be optimized. Employing the differential drag based methodology allows for virtually propellant-free control of the relative orbits, since the motion of the panels can be solar powered.

About the Speaker

Dr. Riccardo Bevilacqua is as assistant professor in the Mechanical, Aerospace, and Nuclear Engineering Department at Rensselaer Polytechnic Institute. Dr. Bevilacqua holds a MSc in aerospace engineering (2002), and a PhD in applied mathematics (2007), both earned at the University of Rome, "Sapienza", Italy. He was a U.S. National Research Council Post-Doctoral Fellow from 2007 to 2010, before joining RPI. He also worked as project engineer in Mission Analysis at Grupo Mecanica del Vuelo, in Madrid, Spain, during 2003. Dr. Bevilacqua's research interests focus on guidance, navigation, and control of multiple spacecraft systems and multiple robot systems. His work involves theoretical investigation, numerical simulations, and hardware in the loop laboratory experimentation.