A novel 2-dimensional electric field sensor based on in-plane micro rotary actuator

This paper, for the first time, proposes a 2-dimensional electric field sensor based on in-plane micro rotary actuator. Compared to the existent electric field micro sensors, which can only detect an axial direction electric field, this sensor is capable of 2-dimensional electric field sensing. In the design of the micro sensor, the combination of angular comb-drives and serpentine springs can bring the advantage of achieving large in-plane rotation, which enlarges the vibration amplitudes and results in more induced charges. Moreover, both push-pull electrostatic actuation method and differential sensing electrodes are adopted to expand the vibration magnitudes and reduce the impact of common mode interference. Experimental results show that this sensor has good linearity of 1.21% in a wide range, and this sensor can detect the X and Y component of electric field with measurement errors better than 8%.