High-Sensitivity MEMS Shear Probe for Autonomous Profiling Observation of Marine Turbulence

Abstract

Autonomous profiling observation of full-depth marine turbulence is very important for ocean research. Anisotropic turbulence near the boundary layer needs to be observed well. However, there is lack of high-spatial-resolution and high-sensitivity methods to fulfill vector turbulence observation. Hence, a highly sensitive bullet-headed MEMS shear probe for observing ocean vector turbulence is developed in this manuscript. The sensing mechanism, design and fabrication are demonstrated in detail. In order to meet the bandwidth requirements for observing ocean turbulence, we perform wet-mode simulations of probe structure to achieve an eigenfrequency of 490 Hz. Through sensitivity calibration experiments, it achieves a sensitivity of 4.84 × 10−2 V·m·s2/kg, which is much higher than those of shear probes reported previously. In addition, the vector test validates that the probe can measure ocean vector turbulence. The results show that the proposed probe is promising in autonomous profiling observation of marine turbulence.