Development of a design method to reduce change propagation effects

his dissertation presents a design method to reduce engineering changes caused due to change propagation effect. The method helps designers to systematically plan a verification, validation, and test (VV&T) plan. The rationale behind such a method is founded on a well-accepted principle that a robust validation plan can reduce engineering changes. However, such method has not yet been developed in mechanical engineering domain for supporting incremental product design, so a method from software engineering has been adopted and extended to address the limitations in the existing design evaluation tools.;Tools extensively used in industry, such as FMEA, and in academia have been reviewed to determine if they can identify different propagation pathways including variant, behavior, organization, and geometric pathways. As a result, it is found that variant and organizational pathways are not identified in any of the reviewed tools --- propagation in these pathways have caused a major product failure in a commercial vehicle and an automatic fire sprinkler manufacturing industries.;A seven-step VV&T method is proposed to address the aforementioned gap in which each step is tailored to suit mechanical engineering needs. The major contribution is developing the construct to identify variant and organization pathways and a prescriptive method. It has been validated in a leading commercial vehicle manufacturer, one of the passenger car manufacturing giants, a rolling mill manufacturer, and an automatic fire sprinkler manufacturer using case study and Delphi validation technique. The results from these studies indicate the proposed VV&T method enables designers to identify variant and organizational pathways and evaluate them, which in turn can reduce engineering changes due to propagation effects. Objective evidence obtained from the fire sprinkler manufacturing company supports this claim explicitly.;"The time saved in finding the issue (using this method) during testing is likely between one and three months...I would estimate the cost savings to be somewhere between...