Complex engineering system development causes various challenges in terms of meeting new product development cost, release time, and product performance goals, along with different sources of uncertainty in the development process. Most of the new product development processes have been experiencing challenges to meet these goals within an increasingly competitive global market environment. Despite decades of industrial experience, it is found that designing and developing increasingly complex products, e.g., aerospace products, still incurs significant cost overrun, schedule delays, and quality issues during design stages. In addition, the reliability of the new product has always been a matter of concern for new product developers and it has been a challenge to balance the development cost and time while increasing product reliability. Achieving a certain level of product reliability through a reliability improvement program, which is one of the new product design objectives, can be accomplished by implementing product verification and validation activities. Design verification and validation (V&V) activities include a set of simple engineering analysis as well as complex engineering activities implemented during the new product development process (NPD) in order to satisfy respective legislative requirements and optimize product technical and functional configurations. The main goal of design V&V process is to mitigate the potential failures of the developed product in the early stages of developing it, since design modifications are inexpensive and easier at early stages, compare to when the product is finalized. Product failure modes, their effects, and a set of V&V activities are outputs of conducting the design failure modes and effect analysis (DFMEA) in the early stages of developing a new product. An optimal design V&V activities plan needs to be provided to mitigate all design failure modes considering that the V&V activities implementation should be cost competitive and on schedule. In reality, each V&V activity can only mitigate a set of failure modes, and its effects on each failure mode are different. The sequencing, repetition probability, duration, and cost of each V&V activity should also be considered when planning the V&V process. In addition, the criticality of failure modes and their coverage are important to have a reliable product by the end of implementing V&V activities. These all necessitate an effective methodology to plan the product V&V activities in the new product development process. Although the existing V&V planning models partially captured some characteristics of implementing the V&V implementation in a NPD process, most of them fall short of quantitatively modeling the V&V implementation process, time, cost and reliability of a new product. Most existing product design V&V planning processes are based on qualitative methods, and there is no research that has studied quantitative methodologies for modeling and optimizing the product design V&V activities by considering the effectiveness of each activity, the sequencing constraint of implementing multiple activities, limited implementation budget and time, iteration of some processes, changes in activity content with iterations, and also the relationship between product design and process design activities,. This research proposes a novel qualitative framework which provides a set of product design V&V activities plan for implementation. Objectives of V&V process including optimal improvement in product reliability, optimal coverage of failure modes, and optimal V&V process time and cost are considered in the simulation model. The simulated V&V plans are compared using the well-known data analysis tool, called Data Envelopment Analysis. Results are the most efficient V&V activities plans for implementation in the product development process. A numerical example is provided to show the application of the proposed approach in the V&V planning for reliability improvement of a new designed engine power assembly is provided.
