How is navigating a unicycle amidst obstacles like manipulating beads on a necklace? This paper addresses that question by introducing a simple control system that appears to offer a common dynamical model for both situations. System (1) consists of a trivially controlled set of “steering” state variables and an additional set of “body” state variables that can be “driven” in a direction determined by the steering variables. The task will be to bring the state of the system to some desired equilibrium using feedback. A defect in the “steered” vector field precludes the possibility of stabilization via a single continuous feedback controller - the essence of what feedback is all about - incurs the necessity of a hierarchical system. For more information: Kod*Lab