In the process of product design and digital fabrication, the structural analysis of a designed prototype is a fundamental and essential step. However, such a step is usually invisible or inaccessible to designers at the early sketching phase. This limits the user's ability to consider a shape's physical properties and structural soundness. To bridge this gap, we introduce a novel approach Sketch2Stress that allows users to perform structural analysis of desired objects at the sketching stage. This method takes as input a 2D freehand sketch and one or multiple locations of user-assigned external forces. With the specially-designed two-branch generative-adversarial framework, it automatically predicts a normal map and a corresponding structural stress map distributed over the user-sketched underlying object. In this way, our method empowers designers to easily examine the stress sustained everywhere and identify potential problematic regions of their sketched object. Furthermore, combined with the predicted normal map, users are able to conduct a region-wise structural analysis efficiently by aggregating the stress effects of multiple forces in the same direction. Finally, we demonstrate the effectiveness and practicality of our system with extensive experiments and user studies.

翻译：在产品设计与数字制造过程中，对设计原型进行结构分析是基础且关键的步骤。然而，在早期草图阶段，这类分析通常对设计师不可见或难以获取，限制了用户对物体物理属性及结构合理性的考量。为弥合这一鸿沟，我们提出了一种创新方法Sketch2Stress，使用户能够在草图阶段对目标物体进行结构分析。该方法以二维手绘草图和用户指定的一个或多个外力作用位置作为输入。通过专门设计的两分支生成对抗框架，该方法能够自动预测法线图以及对应的结构应力图，并使其分布于用户所绘草图的底层物体上。据此，设计师可轻松评估物体任意位置所受应力，并识别草图对象的潜在问题区域。进一步地，结合预测的法线图，用户可通过聚合同向多个力的应力效应，高效地开展区域级结构分析。最后，我们通过大量实验和用户研究验证了该系统的有效性与实用性。