Safety and Verification of Advanced Maritime Vessels - An Approach Based on Systems Theory

Abstract

The past few decades have seen rapid technological development in ships and offshore vessels. Advanced electrical power plants and dynamic positioning (DP) systems are now widespread, and the growing demand for greener and smarter multifunctional vessels has resulted in a top layer of automation of vital vessel functions such as motion control and energy management. Technological developments have made new types of complex operations possible, and can be expected to continue to do so in the future. Smarter and more advanced vessels, however, do not necessarily imply increased safety. Increasing complexity and technological change make old methods for hazard identification and verification inadequate. Experience of designing and safely operating previous generations of vessels may not be directly applicable to future vessels. The main objective of the research presented in this thesis has been to improve and advance our current understanding of how to design and verify safe vessels. Although my work focuses primarily on DP vessels, the basic principles and methods developed also apply to other types of advanced marine systems. The research may also be relevant to other industries. Ensuring the safe design and operation of an advanced vessel is not trivial. Challenges range from training system operators to be able to handle vessels safely, to ensuring high reliability of their technical systems. Today, such challenges are treated separately. The research described and discussed here indicates that these challenges are coupled, and that adopting a holistic perspective that integrates efforts from different engineering disciplines therefore is essential. The overarching objective of this thesis has been refined into the following three research objectives: 1. To analyze and improve current methods and practices for hazard identification and accident prevention in advanced vessels. 2. To analyze and improve the verification process employed to ensure that advanced maritime systems are safe and suitable for safety-critical maritime operations. 3. To investigate how safety can be monitored and understood during the operation of advanced vessels. The work presented here reviews current methods and practices and identifies the main challenges that the maritime industry faces with respect to the above research objectives. The research proposes methods and approaches to improve the current state by addressing the identified challenges. The main contributions of the thesis are summarized as: - Identification of knowledge gaps and the acquisition of knowledge related to prevention of accidents with advanced maritime vessels. - Proposal for a method for hazard identification and accident prevention to be employed during the design phase of advanced maritime vessels. - Proposal for a method for the organization and better utilization of current actions for safety verification of advanced maritime vessels. - Proposal for a method for deriving, utilizing and adapting safety requirements for novel systems to which earlier requirements and experiences are not directly applicable. - Identification of key requirements and outline of a framework for dynamic risk models for DP systems.