External Force Sensing Strategy for Surface Tension Based on SMS Fiber Structure

An external force sensing strategy based on the bend and strain characteristics of SMS fiber structure for liquid surface tension is demonstrated in this work. The bent SMS fiber structure is used to optimize the traditional pull-off method by improving the measurement of the tensile force. Experimental results show that the sensitivity of the sensor is 1.97221 nm/mN, suitable for measuring small tensile forces, with the minimum force change of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10.1409~\mu $ </tex-math></inline-formula> N and the linearity of 99.85%. The maximum relative error of LSTC is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pm 0.282\times 10^{-3}$ </tex-math></inline-formula> N/m. Theoretical and experimental results prove that using a bent SMS fiber structure is a feasible approach for accurately measuring liquid surface tension.