  In this paper we present an energy shaping control law for set-point
regulation of the Chaplygin sleigh. It is well known that nonholonomic
mechanical systems cannot be asymptotically stabilised using smooth control
laws as they do no satisfy Brockett's necessary condition for smooth
stabilisation. Here, we propose a discontinuous control law that can be seen as
a potential energy shaping and damping injection controller. The proposed
controller is shown to be robust against the parameters of both the inertia
matrix and the damping structure of the open-loop system.
