The Role of Testing in Engineering Product Development Processes

Testing components, prototypes and products comprise essential, but time consuming and costly activities throughout the product development process particularly for complex iteratively designed products. The planning of testing is a critical challenge for these complex products for which market pressures demand shorter development times. A literature review identified that testing in the design process is a relatively under researched area. An extended case study in a diesel engine company was therefore conducted to explore how testing is integrated into the product development process and how different types of testing are planned across the stages of product development. The first part of this research study reports the empirical study. A framework resulting from this work is proposed which identifies the entities that characterise how testing should be planned. Motivated by needs of companies and research gaps identified in the literature review, the second part of this study focuses on three key problems for planning of testing in product development process: prioritisation of testing activities, scheduling of testing activities and managing the overlapping of testing and design activities. A method of integrating Quality Function Development (QFD) and Failure Modes and Effect Analysis (FMEA) for prioritising testing activities has been proposed, which can improve the current test prioritisation process of the company. A Multiple Domain Matrix (MDM) is created consisting of the components and associated tests of a product arranged in a format that allows the dependency and interrelationships between key parts and tests to be identified. This form of representation together with the proposed prioritisation method will improve the process of organising and scheduling the testing activities. The final study shows how virtual testing can mediate information flows between overlapping physical tests and (re)design and mitigate the risk associated with overlapping process. The study proposes a significant modification to the existing product development process configuration for design and testing. This reconfiguration makes explicit use of virtual testing which is an extension to Computer Aided Engineering. Virtual testing mirrors the testing process through modelling and simulation, as a distinct and significant activity. Virtual testing is used to (a) enhance and (b) replace some physical tests. Finally, this study assesses the costs and risks of overlaps and their amelioration through targeted virtual testing