Development of RF Resonator-Based 3-D Printed Tilt Sensor

This letter describes the development of an RF resonator-based tilt sensor. The sensor is designed using 3-D printing and metallization. It operates in the frequency range of 1 to 2 GHz. The essential parameter to detect the change in the tilt or inclination of the surface is variation in resonant frequency. The RF-based 3-D-printed tilt sensor consists of two parts. One is a semicircular fixed hollow RF resonator, and the other is a semicircular pendulum. Due to the inclination of the surface, the pendulum will move inside the hollow RF resonator, which results in change in relative permittivity and, consequently, the variation in resonant frequency. Using an RF resonator and pendulum-based structure with 3-D printing make it applicable for wide range, low cost, and accuracy. This sensing system provides a linear correlation and resolution of 2 MHz.