Co-Simulation of a Marine Offshore Vessel in DP-Operations Including Hardware-In-the-Loop (HIL)

Abstract

In this work, a co-simulation case study of a marine offshore surface vessel in Dynamic Positioning (DP) operation, where the DP-controller is placed on an Arduino® micro-controller, is presented. The reasons for using co-simulation are that it is possible to distribute the model among different cores in one computer as well as among different computing members over a local area network. Also, it is possible to export submodels from different software and connect them together in a common simulation. This enables the use of suited modeling software for different types of dynamical systems, as well as hardware, such as micro-controllers for Hardware-In-the-Loop testing. Such an integrated and open simulation method facilitates the development of new products as well as shortening the iterative process in design phases. As for co-simulation standard, the Functional Mock-up Interface (FMI) for co-simulation will be used in this work, and a communication Functional Mock-up Unit (FMU) that communicates with hardware and handles the signal flow between the hardware and the co-simulation will be developed. In the case study, a DP-controller is implemented on the microcontroller and connected to a filter, a position reference system and an offshore vessel model, all implemented as FMUs in the total co-simulation. For simulation master algorithm, the open source software “Coral”, that was developed in the knowledge building project “Virtual Prototyping of Maritime Systems and Operations” (ViProMa), will be used. The simulation results show that even though the micro-controller is set to communicate with a lower frequency than the rest of the co-simulation submodels, the total c-simulation is stable and produces good results. It also show that the FMI standard facilitates hardware in the loop in the co-simulation, and that the co-simulation master algorithm Coral is suited for such simulation cases.