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必要的步骤。然而，在设计初期草图阶段，这类分析通常对设计师不可见或不可及，限制了用户对形状物理属性与结构合理性的考量。为填补这一空白，我们提出了一种名为Sketch2Stress的创新方法，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及用户指定的一处或多处外力位置为输入，通过专门设计的双分支生成对抗网络框架，自动预测出用户所描绘物体上的法向图及对应的结构应力分布图。由此，设计师可轻松检查草图物体各处的应力状况，并识别潜在问题区域。进一步地，结合预测的法向图，用户能够通过聚合同方向多力的应力效应，高效进行区域级结构分析。最后，通过大量实验与用户研究，我们验证了该系统的有效性与实用性。