The FRISC is a high speed craft of the Netherlands Navy which came into use in 2012. Because these vessels sail with speeds up to 45 knots in inshore waters, a large amount of focus and accurate path following is needed for safe navigation, and due to large accelerations, there is a high level of physical strain. These two factors cause a high (prolonged) mental and physical workload which can heighten mental and physical fatigue, resulting in higher risks due to reduced alertness and mental performance. With this in mind, the focal point of this thesis is to increase the safety of the FRISC during high speed navigation by increasing the path following performance and reducing the level of fatigue through lowering the workload. With extensive literature research a possible solution was found to increase the safe navigation. Namely, haptic feedback which will decrease the workload and increase the path following performance. With this in mind, the following research question arises:
To what extent can haptic feedback, implemented into the steering system of the FRISC, contribute to safe navigation during (nightly) high speed inshore navigation?
A FRISC operates with high speeds in inshore waters, following a well prepared detailed planned route. During such an operation the FRISC is subject to performance shaping factors, factors “which influence the likelihood of an error occurring” [1]. With the use of the literature, a possible solution for almost all the factors, related to the FRISC, were found. This solution is a haptic feedback system which will lower the workload and increase the path following performance. An active guidance system is developed with two types of controllers (waypoint controller and XTE controller) to “advise” the operator with the correct rudder angle, to follow a preplanned route during high speed inshore navigation. The contribution of this thesis is tested by the implementation of a haptic shared control, and by investigating the cross track error and the workload. The results of the investigation of the XTE were unambiguous. The XTE controller lowers the mean and median XTE values by 20% and the absolute maximum value is lowered by 37% compared to manual control. The waypoint controller resulted in higher XTE values which means that manual control has the preference above the waypoint controller based on the XTE. Furthermore, the participants indicated that the perceived workload was 37% and 44% lower with the use of the waypoint controller and XTE controller respectively. The physical workload was compared between the experience of the participants and the measured physical demand. This comparison resulted in the fact that the experience of the participants was not in line with the actual physical effort. The physical effort was the highest with the use of both controllers whereas the experience of the physical workload was the lowest. This was assumed to be less important than the perceived workload and therefore it did not influence the conclusion of haptic feedback lowering the workload. Altogether, it is stated that the use of the correct haptic shared control system could increase the safety of navigating during (nightly) high speed inshore navigation.