This video presents the One-Wheel Cubli, a three-dimensional pendulum system, that can balance on its pivot using a single reaction wheel. How is it possible to stabilize the two tilt angles of the system with only a single reaction wheel?
The key is to design the system such that the inertia in one direction is higher than in the other direction by attaching two masses far away from the center. As a consequence, the system moves faster in the direction with the lower inertia and slower in the direction with the higher inertia. The controller can leverage this property and stabilize both directions simultaneously.
Researchers: Matthias Hofer, Michael Muehlebach, Raffaello D'Andrea
Design: ...