A Low-Cost Open-Source Uniaxial Tensile System for Soft Tissue Testing

The evaluation of soft tissue biomechanical properties is of paramount importance not only for a comprehensive understanding of human physiology and physiopathology, but also in the research and development of bio-compatible artificial tissues with viscoelastic properties. Contrarily to standard tensile testing devices, a system intended for biomaterials testing should consider low stress and high strain ranges, characteristic of human tissues; moreover, such a system should enable the ex vivo simulation of biological environmental conditions. Commercial solutions address these challenges, although they are expensive for most academic and research institutions. This study presents a low-cost open-source design solution for soft tissue tensile testing, offering an affordable solution, yet without compromising the high quality and precision of the results. The proposed uniaxial tensile system allows for sample testing at room temperature as well as in a temperature-controlled liquid environment. Moreover, custom clamps ensure the fixation of tissue samples without slipping or tearing. System validation is performed using the tensile testing of springs and 3D-printed soft polymeric samples, demonstrating accurate results compared to the available data. The system is suitable for educational, research, and development applications.