Hull Optimization of the unmanned AGaPaS Rescue Vessel

Crew safety is a key parameter for any seagoing mission. Although today's standards are high, occasionally people go overboard while working on deck. In this case the probability of survival remains low. The joint research project "AGaPaS" [1] aims to significantly increase the chances of survival for a drifting person. Its main objective is to develop a self activating, partially autonomously operating rescue system, able to search, find and rescue people gone overboard. A crucial part of the system is a remotely operated vessel, which is released by free fall from a mother ship. This paper focuses on the hull optimization of this rescue vessel, considering various aspects. The rescue operability has first priority and leads to numerous system specifications such as main dimensions. In addition, adequate seakeeping behaviour is a prerequisite for the successful recovery of a person in distress. This includes small relative motions between the vessel and the drifting person. Moreover, the vessel's free fall characteristics are to be analyzed. Here, particular interest has been laid on the reduction of the peak acceleration as well as on transferring the vertical velocity into a horizontal motion, in order to minimize the risk of a collision with the mother ship. Various hull geometries have been investigated by means of numerical methods as well as model tests leading to the final hull design of the unmanned AGaPaS rescue vessel.