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Based on fieldwork carried out on two Engineering and Physical Sciences Research Council‐funded projects in the area of design, the paper presents the details of an assessment approach which has been developed to assess the use and application of quality tools and techniques in the new product design and development process. Its use will help management recognise the symptoms, root causes, issues and problems that are adversely affecting NPDD, with respect to application (or lack of it) of quality tools and techniques.

A shrink-®t is a semi-permanent assembly system that can resist the relative movement or transmit torque between two components through the creation of high radial pressures at the interface of its constituent parts. The traditional approach to determine the holding torque of a shrink-®t is based on Lame 's equation to predict radial pressures at the interface of the components and knowledge of the coe cient of friction and length of contact. This paper examines the validity of this approach and a variant, which takes into account surface roughness conditions of the interfacing components, by comparing statistical distributions of the holding torque with those found experimentally for a sample of a particular shrink-®t con®guration. The probabilistic results of a micromechanical approach are presented which show good comparison with experimental results, indicating that current design formulae are inadequately predicting holding torque. In addition, the phenomenon of increased holding torque with loading cycle number is observed experimentally, and areas where further work needs to be conducted in order to model the situation using frictional and plastic shakedown are outlined.

This paper presents results from a coupled thermal and power loss analysis of an open-slot permanent magnet (PM) generator. The research focus has been placed on the winding design providing minimum power loss at ac operation together with low-cost manufacture. The analysed PM generator is intended to operate at fixed-speed allowing for the winding design to be finely tuned for the single operating point. Such a design approach has not been widely reported in the literature, and the existing body of work is focused largely on the variablespeed applications, where the winding design is a compromise between the low-and high-speed operating points, for a given torque speed envelope. The ac winding power loss has been analysed for several winding variants with different conductor dimensions accounting for the winding operating temperature. The calculated results suggest that in the analysed PM generator, lower winding slot fill factor is preferable as compared with the more common approach, where the highest manufacturable winding slot fill factor is usually considered. The power loss predictions have been supplemented with thermal analysis of the complete generator assembly for the winding variants considered illustrating the importance and influence of the appropriate winding design on the power output capability of the fixed-speed PM generator. The most promising winding design for the minimum power loss at the rated operating point has been down selected for prototyping. Theoretical findings from the analysis have been compared against experimental data from hardware tests on a stator winding section showing close agreement. I.

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The early use of design tools in new product development has a significant impact on competitive business performance. However, their implementation by companies is not always successful. The main aim of this paper is to enhance research methodology for the development of new design tools to aid successful industrial implementation. A survey of existing research associated with the development and implementation of a wide range of design tools is reviewed, and categorised in terms of their ideal attributes, why, how and when they should be implemented, who should be involved, and where they are best positioned in the product development process. Known issues considered as implementation barriers are also presented in terms of practitioner and manager perspectives. Priority implementation issues are further identified from requirements analysis and the implementation history of four specific design tools at different implementation statuses. These qualities are then discussed in the context of enhancing research methodology for design tool development.