An integrated computer aided design system for railway freight vehicles

摘要

This thesis investigates, with particular reference to New Zealand Railways Corporation, the use of computers in the design of railway freight vehicles. An investigation was carried out into ways of integrating the relevant published works, procedures used in NZR wagon design, and the design and operational experience of NZR staff. The scope of this work did not extend to detailed study of draughting, graphic, and technical office activities as these problems have been and continue to be extensively investigated by other workers. The results of a literature survey, a survey of NZR Design Office procedures and documentation, and staff interviews are presented. This information was used to produce the functional specification of an integrated computer-based scheme presented in the thesis. The features of a prototype system developed to fulfil some of the more fundamental aspects of the specification are described. The prototype system used a commercially available relational database management system to store instances of analysis variables, approved project data, catalogue data, and the relationships between instances. The relationships between instances of analysis variables serves to maintain integrity in an active design project and acts as a "computerised notebook". The prototype system offered the wagon designer substantial flexibility in the use of data and over the control of execution. The author suggests that extensions and changes can be easily implemented in the prototype system. Experience with the use of this prototype system is presented and views regarding its proposed development are expressed. The feasibility of much of the specification was demonstrated and an assessment of probable benefits and costs showed that such an integrated scheme would overall contribute more than other approaches to the corporate objectives.