Combining Sliding Mode and Passivity-Based Control for Manifold Design and Robustness Enhancement

The design of suitable sliding manifolds remains one of the main bottlenecks in sliding mode control. This paper proposes a strategy to address this problem for a broad class of nonlinear systems. To this end, we develop an original, systematic methodology to design stabilizing sliding manifolds for a class of nonlinear port-Hamiltonian (pH) systems. In particular, we exploit the pH structure of the system to design a sliding manifold, where the system preserves the desired passivity properties that are useful to stabilize the dynamics of the system on the designed manifold. The proposed modular control design offers significant advantages compared to the individual application of sliding mode control and passivity-based control techniques, effectively simplifying the design and enhancing robustness. Finally, the applicability of the proposed strategy is assessed via simulations.