Way point tracking of a spherical pendulum inverted

The paper addresses the problem of way-point tracking for the spherical inverted pendulum under the influence of a planar force. A nonlinear controller is proposed that drives the pendulum to track an ordered sequence of desired translational positions (xr:yr) by visiting their neighborhood Nμ, in an inertial reference frame while stabilizing the pendulum about the upper equilibrium. The way-point tracking controller incorporates two parts: a nonlinear control law (we choose from our previous "global" or "semi-global" nonlinear controllers); a reference signal. The stability analysis is carried out. The effectiveness of the proposed strategy is evaluated in computer simulation. © 2007 IEEE.