PendCon Research: Swinging-up a Double Pendulum
Swinging-up a Double Pendulum
With the help of a state-of-the-art nonlinear controller, the PendCon system performs transitions between various equilibrium points. The controller belongs to the class of "two degrees of freedom" controllers and is composed of two blocks: A feedforward input that is calculated offline using numerical algorithms and a linear quadratic (LQ) controller that locally stabilizes the system along the predefined state trajectories, ensuring high robustness to external disturbances and system uncertainties.
The upper figure shows the simulated (blue) and measured (red) quantities for a swing-up of the double pendulum. Upper figure: del, angle between the links; middle figure: phi, angle of the motor-sided link; lower figure: current.
The lower figure shows how the pendulum passes through various equilibrium points (do: hanging, up: inverted):
do,do → up,do → up,up → do,do → up,up → up,do.
On the first place in this notation is the non-actuated link.
