  In this work, we propose a new passivity-based sliding mode control method
for mechanical port-Hamiltonian systems. Passivity-based sliding mode control
(PBSMC) is unification of sliding mode control and passivity-based control. It
achieves sliding mode control and Lyapunov stability simultaneously by
employing an energy based Lyapunov function. The proposed method gives a family
of stabilizing controllers which smoothly interpolates passivity-based control
and sliding mode control with free parameters. The freedom is useful to adjust
the trade-off between robustness against external disturbances and undesired
chattering vibration. In addition, this paper relaxes the restrictive condition
which is required in the authors' former result. As a result, we can apply the
proposed PBSMC method to trajectory tracking control problems. Furthermore, the
robustness of the proposed controller against matched and unmatched
disturbances is investigated. Numerical examples demonstrate the effectiveness
of the proposed method.
