This paper presents a steering method for a car-like vehicle providing smoo
th paths subjected to curvature constraints. We show how to integrate this
steering method in a global motion planning scheme taking obstacles into ac
count. The main idea of the paper is to consider the car as a 4-D system fr
om a kinematic point of view and as a 3-D system from a geometric point of
view of collision checking. The resulting planned motions are guaranteed to
be collision-free and C-2 between two cusp points.