Integrated robust parameter design and tolerance design

Robust design has been gaining plenty of attention in both academia and industry over the past two and half decades. However, there is still some room for improvement. In this dissertation, several drawbacks of the existing robust design methods were identified and analysed. An integrated robust design framework was proposed to help achieve robustness against both external and internal noises. A Steepest Descent Driven Parameter Design method was developed to enhance robust design. Also developed was an improved loss function for robust tolerance design. The proposed methodology was applied using computer simulation experiments to optimise the design of a state-of-the-art injector in a high pressure common rail injection system in a diesel engine. It was demonstrated that the injector performance was significantly improved with the proposed method.