Most commercially-available mechanical testing devices are bulky, expensive, and unable to evaluate changes in sample microstructure under load. This leaves a crucial gap in understanding between material structure and bulk mechanical properties. Our objective was to fabricate a mechanical testing device small enough to fit in most upright or inverted microscopy stages and able to position samples to allow for simultaneous mechanical and microstructural characterization. Parts were 3D printed using the hobbyist-friendly Fused Filament Fabrication technique, then assembled with commercial fasteners and translation components to create a mechanical testing device that utilized the deflection of plastic posts to determine sample reaction forces under applied strain. Video of sample deformation was analyzed using a custom processing script to calculate stress and strain behavior in an automated and high-throughput manner. This device was able to perform mechanical characterization with an accuracy comparable to commercial mechanical testing devices for a wide range of nonlinear and viscoelastic samples under dry and hydrated conditions. Additionally, the device showed compatibility with different upright and inverted microscopes and was able to demonstrate accurate mechanical testing results when used with these instruments. We successfully developed a device capable of accurately testing a majority of soft materials in the field of Biomedical Engineering with the ability to perform additional microstructural characterization using microscopy at a price point of $600.

大多数市售的机械测试设备体积庞大、价格昂贵，并且无法评估负载下样品微观结构的变化。这在理解材料结构和整体机械性能之间留下了关键的差距。我们的目标是制造一个足够小的机械测试设备，以适应大多数直立或倒置显微镜载物台，并能够定位样品以允许同时进行机械和微观结构表征。使用业余爱好者友好的 Fused Filament Fabrication 技术对零件进行 3D 打印，然后与商业紧固件和平移组件组装在一起，以创建一个机械测试设备，该设备利用塑料柱的偏转来确定施加应变下的样品反作用力。使用自定义处理脚本分析样品变形的视频，以自动化和高通量的方式计算应力和应变行为。对于干燥和水合条件下的各种非线性和粘弹性样品，该设备能够以与商业机械测试设备相媲美的精度进行机械表征。此外，该设备显示出与不同的正置和倒置显微镜的兼容性，并且在与这些仪器一起使用时能够展示准确的机械测试结果。我们成功开发了一种设备，能够准确测试生物医学工程领域的大多数软材料，并能够以 600 美元的价格使用显微镜进行额外的微观结构表征。