Control-Lyapunov Functions for Systems Satisfying the Conditions of the Jurdjevic-Quinn Theorem

For a broad class of nonlinear systems satisfying the Jurdjevic-Quinn conditions, we construct a family of smooth control-Lyapunov functions whose derivatives along the trajectories of the systems can be made negative definite by smooth control laws that are arbitrarily small in norm. We also design state feedbacks of arbitrarily small norm that render our systems integral-input-to-state stable to actuator errors.