Passive and wireless strain sensor based on LC circuit with lamination fabrication

From traditional manufacturing to integrated circuit technology, shaft components have been utilized in different kinds of industries. Therefore, torsion monitoring to maintain the precision of machines is an important task. However, in order to check the performance, the shaft component needs to be dismounted from working position and installed in an expensive testing system for further diagnoses, which is labor-consuming and inefficient. In this study, we proposed a passive, wireless smart LC sensing tag based on the developed LC technology produced by commercial aluminum foil lamination and fast slitting techniques. With this smart tag fixed on the shaft, the torque generated by the system can be monitored, since the resonance frequency, shifting accordingly to the change of torque, can be readable by RF coils' inducting. Therefore, the smart LC sensing tag can work wirelessly and passively without physically connecting to a battery or power module. The goal of this study is to monitor stress at least 0.0056ϵ by using the portable antenna analyzer which has the resolution about 1.3113MHz/ϵ. This technology has the great vision that applies to the shaft monitoring in vehicles or fabrication machines. Furthermore, it can be integrated into IOT application.