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Abstract The authors address the problem of tuning a non‐linear energy‐based regulator for the positioning of a surface marine craft. Interconnection and damping assignment passivity‐based control (IDA‐PBC) is used for the control design, resulting in passive target dynamics that can be expressed as a port‐Hamiltonian system (PHS). The IDA‐PBC methodology has been successfully utilised in several applications, however, there has been minimal development in tuning methods that can analytically assist the designer to achieve desired response characteristics. It is demonstrated that eigenvalue assignment of the linearised target dynamics in PHS form can significantly aid the tuning process. Based on this analysis, the authors propose a systematic tuning approach to achieve certain performance and response characteristics. A comprehensive demonstration of the proposed tuning method is provided for the position regulation of an underwater vehicle in the horizontal plane in a case study, where numerical analysis of robustness is also conducted.

In this paper we present a robust trajectory tracking control for a fully actuated marine surface vehicle. The tracking controller is obtained using a port-Hamiltonian model of the marine craft and includes an integral action to compensate for constant disturbances. The proposed approach adds damping into both the position and integrator coordinates, leading to input-to-state stability with respect to time-varying disturbances. We exemplify this controller with a simulation for an unmanned surface vehicle subjected to constant and time-varying wind disturbances. The tracking controller rejects the disturbances achieving global exponential stability for constant disturbances and input state stability for time-varying disturbances.

In this paper, we address the control design problem of positioning of over-actuated marine vehicles with control allocation. The proposed design is based on a combined position and velocity loops in a multi-variable anti-windup implementation together with a control allocation mapping. The vehicle modelling is considered with appropriate simplifications related to low-speed manoeuvring hydrodynamics and vehicle symmetry. The control design is considered together with a control allocation mapping. We derive analytical tuning rules based on requirements of closed-loop stability and performance. The anti- windup implementation of the controller is obtained by mapping the actuator-force constraint set into a constraint set for the generalized forces. This approach ensures that actuation capacity is not violated by constraining the generalized control forces; thus, the control allocation is simplified since it can be formulated as an unconstrained problem. The mapping can also be modified on-line based on actuator availability to provide actuator-failure accommodation. We provide a proof of the closed-loop stability and illustrate the performance using simulation scenarios for an open-frame underwater vehicle.