Trans RINA, Vol 152, Part A2, Intl J Maritime Eng, Apr-June 2010 DISCUSSION


THE EXTENSION OF SYSTEM BOUNDARIES IN SHIP DESIGN


A Hagen, DNV/Norwegian University of Science and Technology, Norway A Grimstad, DNV, Norway


(Vol 152 Part A1 2010)


COMMENT Professor D Andrews, University College London.


This paper is to be welcomed as it argues for the broadening of ship design from what has generally been too narrow a focus in most cases due to the ship design process being a largely evolutionary approach. Given current


approach is


environmental strongly


preoccupations, the authors’ driven by


sustainability, in contrast concerns over some other broadening


approaches have, for example, done so with an emphasis on ship architecture [23, 24]. Thus the authors’ approach seeks to make the profession recognise that even at the preliminary stages of ship design that it is complex and challenging but more appropriate in having a wider boundary than a directly (or simplistically) economic one.


The desire to be more comprehensive is perhaps overly constrained by the view in Figure 4 that all ships are part of a transport system, as such an approach would exclude all service vessels (e.g. OSVs, naval vessels, fishing craft, pleasure craft) and, perhaps, even cruise ships, which


primarily entertain, rather than transport,


passengers. Perhaps a better super-system is a fleet, which could encompass all form of transportation as well as ships that go to sea to conduct evolutions as part of a wider service system [25].


At the start of Section 3.1 the authors remark that the ongoing development of a ship design can influence the owner’s


views to the in for extent that “requirements


themselves change”. This is strongly supported as it is good (i.e. pragmatic) systems engineering, unlike the current obsession, acquisition, naively,


example some naval believes that the the requirements, ship


with Requirement Engineering. This, customer can endlessly


investigate a “functional” (i.e. non material specific) statement of


diminished in the next sub-section rather than adopt a


Requirements Elucidation process, as advocated by this commentator [26]. However this support by the authors for a more sophisticated view of initial ship design is somewhat


reference to Dillon [15] and an apparent endorsement of the view that the “Owners requirement “ is the design


by


start point. This commentator is clear that a sensible owner should initially limit themselves to a broad expression of need and that this would then be much more consistent with the ship concept process being essentially a genuine dialogue, which would jointly elucidate the “wicked problem” [16] of what is sensible and affordable. It is also pleasingly noted that the latter problem has been recognised


by the


fundamental to the nature of ship design. The authors go on to argue for “rapid


authors as re-entry” or


flexibility in tackling the steps in the design spiral (or 3- D cone) rather than a, seemingly, mechanistic sequence implied by the left hand “slice” of Figure 7. This comment well points out the danger in any attempt to describe the design process for physically large and complex systems, such as sophisticated ships. No representation is really without its flaws in trying to represent a very complex process [16]. Every design on which this commentator has been involved has been different from every other importantly, each design’s


in the actual process and, precise design


driver(s),


which should alert the design team to alter the design focus and even the sequence in which the various aspects are tackled. It was for this reason that this commentator has advocated every designer should at least use or, best, create whatever model of the process they feel most comfortable with. To this end, the recent IMDC State of Art Report on Design Methodology reproduced some 27 diagrammatic representations of the ship design process, each with key statements to show their particular merits or applicabilities [27]. The authors are therefore asked to comment on that set of representations to say which they find most useful and whether there are others that they might wish to see added to the IMDC set.


Professor V Bertram, FutureShip GmbH, Germany


I congratulate the authors to their article. The theme of “design for transport chain” comes at the right time and is highly important. Naval architects traditionally system designers. Considering larger systems like fleets or intermodal transport chains is a natural extension of the traditional single ship design. It adds an important and lucrative design level (both in terms of micro and macro economies).


The basic idea is not new, but largely forgotten or ignored. The concept of designing maritime transport chains dates at least back to the 1970s when Prof. H. Schneekluth presented economic optimization on fleet levels. [Aggregated summaries of his work in English can be found in Ref 28] However, legal and economic boundary conditions as well as technical options have changed drastically in the last 40 years. Unfortunately, as the authors point out so rightfully, the tools for single


© 2010: The Royal Institution of Naval Architects


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