Toward a Method for Achieving Synergy between Heuristic Rules of Thumb and Quantitative Methods in Engineering Design

工程设计专家的启发式经验法则通常在做出设计决策时节省时间和金钱。通过多年的产品设计、材料和制造经验，专家可以快速执行许多设计任务，例如缩小可能的设计选项集以进行进一步调查。然而，有时这些捷径会导致糟糕的设计决策，浪费时间和金钱。当考虑新的材料、制造技术或产品类型时，这种情况尤其会发生。旧的经验法则不再适用，即使是专家也很容易受到“认知偏差”的影响，也就是我们有时都会陷入决策陷阱。虽然数学模型和方法可以缓解这一问题，但它们往往需要巨大的成本和努力才能实现，因此抵消了预期的好处。这个项目将结合两个世界的最好，致力于确定快速启发式策略和更严格的设计决策量化方法之间的最佳平衡的方法，从而使社会受益。这个项目的智力意义在于为一种新的、正式的设计方法奠定基础，该方法利用启发式方法和规范方法之间的协同作用。这个项目将分析一个高级系统工程问题的设计过程，其中要求设计者扩展分析框架，以包括以前从未考虑过的问题。诸如优化和基于决策的设计等标准方法考虑了不确定情况下的效率和权衡，具有与以前仅应用于物理系统建模的相同程度的分析严格性。虽然这种方法在某种程度上是成功的，但有时这种方法的成本(公式、数据收集、求解)根本不值得努力。相反，设计专家使用的启发式“经验法则”速度更快，但有时可能会因为系统的认知偏差而导致次优结果，这些系统认知偏差无意中嵌入到启发式中，并导致设计选择偏离最佳解决方案。这里解决的问题是，严格的启发式设计方法可能导致劣质的解决方案，而严格的标准化方法可能太耗时且成本太高，无法实现。将分析观察到的启发式方法，以确定它们对设计过程和最终产品的影响。将以同样的方式分析规范方法。然后，将开发一种确定这两种方法的最佳组合的方法。该项目将为制定一套完整的“合理设计分析规则”奠定基础，以确定规范方法和启发式方法的最佳组合。

Engineering design experts' heuristic "rules of thumb" usually save time and money when making design decisions. Through years of experience with product design, materials, and manufacturing, experts can perform many design tasks quickly, such as narrowing the set of possible design options to investigate further. Sometimes, however, these shortcuts result in poor design decisions that waste time and money. This happens especially when new materials, manufacturing technologies, or types of products are being considered. The old rules of thumb no longer apply, and even experts can be vulnerable to "cognitive biases," or decision traps that we all sometimes fall into. Although mathematical models and approaches can alleviate this problem, they often require significant cost and effort to implement and therefore counteract the desired benefit. This project will benefit society by combining the best of both worlds, working toward a methodology for determining the best balance between rapid heuristic strategies and more rigorous quantitative methods for making design decisions. The intellectual significance of this project lies in building a foundation for a new, formal design methodology that exploits the synergy between heuristic and normative methods. This project will analyze a design process for one advanced systems engineering problem, where the designer is required to expand the frame of analysis to include issues never before considered. Normative methods such as optimization and decision-based design consider efficiency and tradeoffs under uncertainty with the same degree of analytic rigor that was previously applied only to physical system modeling. While this approach has been successful to some extent, there are times when the cost of this approach (formulation, data gathering, solving) is simply not worth the effort. Conversely, the heuristic "rules of thumb" employed by design experts are faster, but can sometimes lead to suboptimal results because of systematic cognitive biases that are inadvertently embedded in the heuristic and lead the design choice away from the optimal solution. The problem addressed here is that strictly heuristic design methods can lead to inferior solutions, while strictly normative methods can be too time consuming and costly to implement. Observed heuristics will be analyzed to determine their effect on both the design process and the resulting product. Normative methods will be analyzed in the same manner. Then, a method for defining the best combination of the two approaches will be developed. This project will provide the foundation for developing a full set of "rules for rational design analysis" for determining the best combination of normative and heuristic approaches.