Feedback control framework for car-like robots using the unicycle controllers

We apologize the readers for the mistake made in equation (53) on page 531, which was found by us in paper [1] after its publication in the Robotica Journal. Namely, values of function s defined in equation (53) are always greater or equal to unity: s(t) ≥ 1 for all t ≥ 0. On the other hand, the inverse 1/s(t), which was used in the left-hand side of (53), belongs to the set (0, 1] (function s was by mistake assigned to this set in definition (53)).