Numerical simulation and performance optimization of underwater piezoelectric artificial lateral line sensor for flow velocity sensing

Abstract In complex underwater flow environments, traditional sonar or vision systems face challenges such as high power consumption, low resolution, and weak anti-interference capabilities, making them insufficient for precise perception required by underwater robots. To enhance flow velocity sensing accuracy while achieving structural lightness and functional integration, this study designs a piezoelectric artificial lateral line sensor inspired by the lateral line system of fish. A two-dimensional piezoelectric-fluid-structure interaction model is constructed using the COMSOL multiphysics simulation platform to systematically investigate and optimize the sensor’s structural parameters. Simulation results reveal that the height of the cilium significantly affects the sensitivity of the sensor. The cilium position exhibits a linear correlation with output voltage, offering theoretical support for directional sensing. Localized suspension at the cilium base enhances structural flexibility, increasing sensitivity from 28.2 mV (m/s) −1 to 66.5 mV (m/s) −1 ; however, excessive suspension may cause instability. The optimal piezoelectric layer thickness is found to be within the range of 4–8 μ m, balancing output voltage (up to 0.32 mV) and material cost. This study reveals the influence mechanisms of structural parameters on sensor performance both qualitatively and quantitatively, providing theoretical guidance and design references for the engineering application of artificial lateral line sensors in microscale underwater flow field sensing.