Bolt Looseness Detection Based on Double Ring Antenna Sensor

Abstract

In this paper, a new antenna sensor based on double ring antenna for bolt loosening monitoring is provided. The sensor consists of two rings with small holes in the outer ring and a parallel capacitor in the double ring. When the inner and outer rings rotate relative to each other, the capacitance inside the antenna sensor will change, resulting in the shift of resonant frequency. Bolt loosening can be determined by the angle of rotation of the antenna sensor. The numerical simulation of the antenna sensor is carried out in High Frequency Structure Simulator (HFSS). Simulation results show that the rotation angle and resonant frequency have good linearity within a certain range.