On PLA-based conformal sensors for detecting the recurrence of diaphragmatic hernia

Abstract

Hernia mesh sensor-based solutions have recently been developed for bovines’ diaphragmatic hernia (DH). But hitherto, little has been reported on the performance of such sensors in detecting the effect of increased abdominal pressure on the diaphragm of the bovines from a conformability viewpoint. This study is focused on the 3D printing of the conformal substrates as passive sensors to detect the recurrence of the DH. Polylactic acid (PLA) based substrate was used to fabricate the biocompatible sensor in this study, and its rheological, thermal, and mechanical properties were ascertained. After establishing the material properties, the substrates were 3D-printed to ascertain the conformability by varying the curvature angles (0°- 45°). For analyzing the sensing capability, the return loss (S11) and resonant frequency (fr) were observed against the conformability of the passive device by simulating in high-frequency structure simulator (HFSS) software and in real-time on the vector network analyzer (VNA). The shift (towards the right) in the fr with the increase in the conformal angle was observed up to 30°, and afterwards, up to 45°, the shift was insignificant. This change in the conformal shape of the sensor imitates the intra-abdominal pressure in the industrial, scientific, and medical (ISM) band to detect the reoccurrence of DH.