Knowledge in the making: Prototyping and human-centred design practice.

This thesis presents an enquiry into the nature and role of prototyping within human-centred design practice, examining the capabilities and limitations of emerging prototyping technologies within this context. A contextual review explores the significance of the human element in design. This leads to the proposal of a paradigm statement for human-centred design which informs the theoretical and practical research activity undertaken in the course of this investigation. A critical review of literature aimed at the design and engineering professions identifies a rhetoric celebrating the virtualisation of design processes. Here, advocates of emerging virtual prototyping technologies argue computer-based simulation techniques may reduce or replace physical prototype iterations, thereby greatly increasing the speed and efficiency of new product development processes. This thesis questions the extent to which virtual prototyping can replace physical human input in design. A counter argument to the designer's total immersion in the virtual design world is that valuable creative opportunities may be revealed through discovery-oriented physical prototyping. Furthermore, it may not be possible to adequately describe all aspects of a design proposal using virtual methods alone. This is demonstrated in practical investigations in which designers sought to exploit tactile qualities as essential features in design, and also in cases involving complex structural behaviour. Despite significant advances in virtual prototyping technologies, there remain some types of design problem which may only be identified and addressed through the making and testing of physical models. Moreover, this thesis argues that the valuable practical knowledge which may be derived through hands-on engagement and manipulation of physical prototypes and materials must be retained as an essential human element in design.