An integrated computational approach to Ship Concept Design using optimization techniques and a knowledge base to control the optimization process has been developed. The system automates both synthesis and analysis; analysis by the repeated sequential use of Design Theory Modules and synthesis through the optimization process, which compromises conflicting requirements, subject to constraints. The intention of this work has been to find a better approach to automated design synthesis and at the same time employ detailed analytical tools such as a three-dimensional hull-form definition and engineering analysis modules. Optimization techniques and a knowledge base are combined to achieve the desired capabilities, taking advantage of the benefits optimization can bring using goal oriented methods and exploratory searches, alongside a knowledge base that controls the synthesis process rather than the design. A function mapping strategy has been developed to provide a multiple-parametric view of regions of the optimization objective function and constraints. A discussion is included on the role of further applications of expert systems to design systems in both synthesis and analysis and their possible interference with creativity and innovation. Two design examples are provided, one showing the application of the system using optimization and the other adding the use of the knowledge base. The results are compared and discussed.

This thesis treats the motion of a small vessel described in six degrees of freedom. There are three are translation equations of motion and the other three are equations of angular motion. The aim is to develop a model with a sound mathematical base and use experimentation to find forces to aid the completion of the model, with the intention of use in an auto pilot, by the following means: 1) By solving the equations of motion for large movements, with given sea and wind conditions and also with given control forces and moments. 2) Deduce the forces and moments being applied from the sea etc., from the motion of the vessel. Thus to enable the auto pilot to deduce the required additional forces and the forces and moments applied by the water and wind and the control devices, such as the propeller and rudder. These two aims are achieved by analysing the transformation of axes using the standard Euler equations. However, as Euler's angles are ordered and therefore cannot cope with large angles which are present in the motion of a small vessel, another set of angles relating to axes and planes have been deduced. These are then rotated and the set of three measured angles are found in terms of the Euler angles. This is the main pan of original work in the thesis. The rest of the thesis is then based upon these set of measured angles and a general case mathematical model is deduced using them. This is proceeded by a functional analysis of the vessel's motion, environment and control action's. After that the general case model is theoretically validated by analysing the work done by ARJM Lloyd and showing how his work is a specific case of the general case. Experimental work performed on a small vessel is then used in the building of a mathematical model for the specific case of a small vessel, using a set of measured angles.

No description available.

No description available.

The advent of high fuel costs and the increasing crowding of shipping lanes have initiated considerable interest in ship automatic pilot systems, that not only hold the potential for reducing propulsion losses due to steering, but also maintain tight control when operating in confined waterways. Since the two requirements differ significantly in terms of control specification it is natural to consider two separate operating modes. Conventional autopilots cannot be used efficiently here, partly because the original design catered for good gyrocompass heading control only, and partly because the requirement of reducing propulsion losses cannot be easily translated into control action in such schemes. Linear quadratic control can be used to design a dual mode autopilot. The performance criterion to be minimised can readily be related to either the propulsion losses while course-keeping, or to the change of heading while manouevring, and therefore, the same controller can be used for both functions. The designed control system is shown, from the computer simulation study, to perform satisfactorily in disturbed seas. However, the need for detailed knowledge of the ship dynamics in the controller design implies that time-consuming ship trials may be required. Hence an alternative method of design using adaptive self-tuning control is studied. Because the self-tuning approach combines controller design and coefficient identification in such a way that the two processes proceed simultaneously, only the structure of the equation of ship motion is needed. As in the case of quadratic control, a well specified performance criterion is firmly linked to the design so that a closely controlled optimal performance results.

No description available.

No description available.

Thesis (Ph. D.)--State University of New York at Binghamton, Department of Electrical Engineering and Computer Engineering, 2006. / Includes bibliographical references (leaves 107-122).

Thesis (M.S. in Mechanical Engineering and Mechanical Engineer) Naval Postgraduate School, June 1998. / Title from cover. Thesis advisor(s): Anthony J. Healey. "June 1998."--Cover. "NPS-ME-98-004"--Cover. Includes bibliographical references (p. 117-118). Also available online.

Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains vii, 83 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 53-57).