R&D on an advanced ride control system for a high speed mono hull

The paper describes the hydrodynamic research into the development of an Advanced Ride Control System for a high speed mono hull ferry: the HSF-ARCoS project. The principles of the ride control system will be briefly described, because this is treated in other papers, Klugt et al (2002). The emphasis of the paper will be on hydrodynamics. For the development of the ride control system it was required to develop a simulation model for a high speed craft operating in waves and/or performing manoeuvres. The basis of a suitable simulation tool was already available in the form of Fredyn. Fredyn is a non-linear motion simulation package for investigating the performance of frigates in moderate to high sea states. For the present purpose Fredyn was adapted to high speed mono hulls by replacing the manoeuvring model for frigates by a dedicated high speed mono hull manoeuvring model and by adding control surface characteristics for T-foils, stabiliser fins, interceptors, trim flaps and waterjet propulsor characteristics. The manoeuvring and several control surface characteristics were obtained from an extensive experimental program in which a series of static and dynamic (PMM) captive model tests were conducted. A reduced version of the simulation model was developed for use in the control system environment. The performance of the developed control system was judged by connecting the control system software to the Fredyn simulation environment. Thus, a very powerful simulator was obtained which enabled the development and evaluation of advanced motion control systems for fast mono hulls.