Control of a spherical inverted pendulum


The spherical inverted pendulum is a cylindrical beam attached to a horizontal plane via a universal joint. The pendulumís universal joint is free to move in the horizontal plane, under the influence of a planar force. Gravity acts on the beam making the downward position the naturally stable position. The control objective considered here is to use the planar force to drive the inverted pendulum in such a way that the upright position is stable and attractive with a large domain of attraction, e.g., the upper half hemisphere. We developed a forwarding based controller for global stabilization of the spherical inverted pendulum. Currently, we are considering alternative stabilization techniques, as well as robustness issues and tracking control.


  • Prof. I.M.Y. Mareels
  • Guangyu Liu (PhD student)
  • Selected publications

  • G. Liu, D. Nesic and I. M. Y. Mareels, "Modelling and stabilization of a spherical inverted pendulum",to appear in 16th IFAC World Congress, Prague, Czeck Republic, 2005.