Collaborative Research: Exploring the Evolution of Design Requirements Throughout the Design Process Using Network Models

所有的设计问题都受到一组在项目交付时必须满足的要求的约束。然而，需求在项目持续时间的跨度内发生变化，导致了“移动目标现象”，并危及项目的成功。需求的变化可能是由于技术、消费者趋势、观念或法规的变化。在设计和制造需要数年时间或包含数万个需求的复杂系统中，这种需求的波动性尤其重要。研究表明，超过一半的失败项目是由于需求及其管理导致的失败，阻碍了美国的市场成功、创新和工程追求。这项研究的目标是了解需求是如何变化的，更重要的是，它们对设计的其他元素的影响。虽然工程师可能会考虑需求更改的影响，但很难处理这会如何影响其他几个需求或系统组件。了解需求是如何变化的，以及它们对设计过程中其他元素的影响可能会改变我们在整个设计过程中设计和利用需求的方式。尽管需求构成了每个工程项目的支柱，但分析需求所需的形式推理支持是有限的。了解它们在设计的早期(启发)和后期(令人满意)阶段之外的使用有助于理解在过渡期间发生的事情，这是一个公认但尚未很好理解的易变过程。这项研究的目的是促进对系统设计中工程需求演变的基本理解。这项研究解决了在描述和规定工程师如何使用需求方面的空白，更重要的是，在整个设计过程中可以使用需求。具体的探索将集中在测量需求波动性，然后预测需求波动性。为此，本研究将加强现有的需求变更传播预测方法，以纳入测量波动性所需的图论度量。定量和定性数据都是在一个为期三年的多案例研究中收集的，该研究涵盖了来自不同设计项目的2760个不同的需求文档。将分析需求及其变更数据，以确定是否可以使用波动性度量来理解需求如何演变。这项研究将使工程师能够在设计过程的早期分析需求，以评估个别需求与其他需求相关时的易变性。这使工程师和设计人员能够在提交更改之前分析更改传播和影响，从而增加设计流程的价值。

All design problems are constrained by a set of requirements that must be satisfied at project delivery. However, requirements change over the span of a project's duration, causing the "moving target phenomenon," and jeopardizing the success of the project. Changes in requirements may occur due to changes in technology, consumer trends, perceptions, or regulations. Such requirements volatility is particularly important in complex systems that require several years for design and manufacturing or those that contain tens of thousands of requirements. Research has shown that over half of failed projects occurred due to failure stemming from requirements and their management, hindering market success, innovation, and engineering pursuits in the United States. The goal of this research is to understand how requirements change, and more importantly, their effect on other elements of design. Whereas an engineer may consider the impact of a requirement change, it is difficult to process how this may affect several other requirements or system components. Understanding how requirements change, and their effect on other elements of the design process may change how we design and utilize requirements throughout the design process.Although requirements form the backbone of every engineering project, the formal reasoning support needed to analyze requirements is limited. Understanding their use outside of the early (elicitation) and late (satisfying) phases of design can contribute to understanding what happens in the interim, a volatile process recognized yet not well understood. The objective of this research is to advance the fundamental understanding of engineering requirements evolution within systems design. This research addresses a gap in both describing and prescribing how engineers use and, more importantly, could use requirements throughout the design process. A specific exploration will focus on measuring and then predicting requirements volatility. To this end, this research will enhance an existing Requirement Change Propagation Prediction Method to incorporate graph theoretic metrics needed to measure volatility. Both quantitative and qualitative data is collected during a three-year, multi-case study spanning 2,760 different requirements documents from varying design projects. Requirements and their change data will be analyzed to determine if volatility metrics could be used to understand how requirements evolve. This research will enable engineers to analyze requirements early in the design process to assess the volatility of individual requirements as they relate to other requirements. This adds value to the design process by allowing engineers and designers a means to analyze change propagation and impact before committing to changes.