DOI
10.5703/1288284318540
Description
Stretchable strain sensors are essential for motion monitoring in wearable systems and soft robotics, requiring materials that combine high elasticity, durability, and stable electromechanical response. In this work, a screen-printable TPU–CNF conductive ink was formulated and used to fabricate stretchable sensors on 3D-printed TPU substrates. Comparison with fully conductive FDM-printed TPU dog-bone samples revealed porosity, weak interlayer adhesion, and unstable resistance, motivating the adoption of a solvent-based ink approach. The TPU–CNF ink produced uniform, well-adhered conductive networks through controlled microcracking during drying, enabling reliable strain sensing across three geometries (i.e., zigzag, interdigitated, line). Mechanical testing showed high elongation and consistent performance, while electrical measurements demonstrated monotonic ΔR/R₀ with strain and geometry-dependent sensitivity. Overall, the TPU–CNF ink established a fully functional platform for stretchable sensing applications, with ongoing efforts directed toward solvent-free material alternatives.
Stretchable Screen-Printed TPU–CNF Sensors: Fabrication and Electromechanical Performance
Stretchable strain sensors are essential for motion monitoring in wearable systems and soft robotics, requiring materials that combine high elasticity, durability, and stable electromechanical response. In this work, a screen-printable TPU–CNF conductive ink was formulated and used to fabricate stretchable sensors on 3D-printed TPU substrates. Comparison with fully conductive FDM-printed TPU dog-bone samples revealed porosity, weak interlayer adhesion, and unstable resistance, motivating the adoption of a solvent-based ink approach. The TPU–CNF ink produced uniform, well-adhered conductive networks through controlled microcracking during drying, enabling reliable strain sensing across three geometries (i.e., zigzag, interdigitated, line). Mechanical testing showed high elongation and consistent performance, while electrical measurements demonstrated monotonic ΔR/R₀ with strain and geometry-dependent sensitivity. Overall, the TPU–CNF ink established a fully functional platform for stretchable sensing applications, with ongoing efforts directed toward solvent-free material alternatives.