A ‘fitness-wheel-shaped’ MEMS vector hydrophone for 3D spatial acoustic orientation

Abstract

For the purpose of acquiring precise underwater 3D spatial orientation, a ‘fitness-wheel-shaped’ MEMS vector hydrophone (FWVH) is developed, which achieves monitoring of a tri-axial acoustic pressure differential via appropriate constructional design and strain readout. Compared to the previously reported T-structure-combined vector hydrophone (TSVH) which has a nonlinear relationship between output and external force, using the FWVH it is feasible in principle to achieve a tri-axial match, which make it promising in accurate acoustic orientation. A theoretic model for sensitivity is developed, where torque moment is taken into consideration to match the simulation and practical results. Superior to 3D force sensors, bandwidth is taken as the key index for the FWVH and is designed in detail with a compromise of sensitivity. In view of the bandwidth, the parameters are determined for detecting the signal in the range 20–300 Hz. A vibration test demonstrates tri-axial resonance frequencies. Finally, the frequency response curve of the FWVH shows that tri-axial sensitivities are consistent, agreeing with the analysis and simulation results, which reach −174 dB (0 dB referring to 1 V µPa−1) at 300 Hz.

New insight into contradictive relationship between sensitivity and working bandwidth of cilium MEMS bionic vector hydrophone

“…In 2016, Wang et al conducted theoretical analysis again, but they still assumed that the cilium is a rigid cylinder [11]. Until now, the single-degree of freedom system has been still used for theoretical analysis [12,13]. In order to solve the contradictive relationship between sensitivity and working bandwidth, Liu et al proposed a 2 × 2 array structure which broadened the bandwidth to 20-5000 Hz [14].…”

Directivity Modeling and Simulation Analysis of a Novel Structure MEMS Piezoelectric Vector Hydrophone

“…According to the sensing mechanism, MEMS vector hydrophones can be mainly divided into capacitive vector hydrophones [ 5 , 6 ], piezoresistive vector hydrophones [ 7 , 8 , 9 , 10 , 11 , 12 ], and piezoelectric vector hydrophones [ 13 , 14 , 15 , 16 , 17 ]. There are few articles available on capacitive MEMS vector hydrophones.…”

“…In 2007, Shang, Chen et al proposed a bionic ciliated MEMS piezoresistive vector hydrophone with an unamplified sensitivity of −247.7 dB [ 9 ]. Building upon this design, they subsequently proposed variations, including the bionic T-Shape [ 8 ], bionic cup-shaped [ 10 ], and bionic fitness-wheel-shaped [ 12 ] MEMS piezoresistive vector hydrophones. Recently, a new design, the Crossed-circle MEMS ciliary vector hydrophone, has been proposed [ 11 ].…”

Batch Transfer Printing of Small-Size Silicon Nano-Films with Flat Stamp

“…For example, in view of the current problem that rigid silicon-based hydrophone cannot be flexible and conformal, silicon nano-films can be used as sensitive units, and flexible materials can be used as structures to make flexible hydrophones, which can realize the micro-nano-flexible heterogeneous integrated preparation of silicon nano-film sensitive units. It can fit with the surface of the unmanned underwater vehicle, realize the two-dimensional vector detection of underwater acoustic signals, perceive the underwater sound field environment information, and play an irreplaceable role in ocean exploration [ 12 ].…”