Man-made flows from a fish’s perspective: autonomous classification of turbulent fishway flows with field data collected using an artificial lateral line

Abstract

The lateral line system provides fish with advanced mechanoreception over a wide range of flow conditions. Inspired by the abilities of their biological counterparts, artificial lateral lines have been developed and tested exclusively under laboratory settings. Motivated by the lack of flow measurements taken in the field which consider fluid-body interactions, we built a fish-shaped lateral line probe. The device is outfitted with 11 high-speed (2.5 kHz) time-synchronized pressure transducers, and designed to capture and classify flows in fish passage structures. A total of 252 field measurements, each with a sample size of 132 000 discrete sensor readings were recorded in the slots and across the pools of vertical slot fishways. These data were used to estimate the time-averaged flow velocity (R = 0.952), which represents the most common metric to assess fishway flows. The significant contribution of this work is the creation and application of hydrodynamic signatures generated by the spatial distribution of pressure fluctuations on the fish-shaped body. The signatures are based on the collection of the pressure fluctuations' probability distributions, and it is shown that they can be used to automatically classify distinct flow regions within the pools of three different vertical slot fishways. For the first time, field data from operational fishway measurements are sampled and classified using an artificial lateral line, providing a completely new source of bioinspired flow information.

Fish under pressure: Examining behavioural responses of Iberian barbel under simulated hydropeaking with instream structures

“…The LLP measures the rapid flow changes (up to 200 Hz) around its body using six differential pressure sensors. The motivation of using a LLP is that it more closely mimics the spatial and temporal sensing capacity of fish in contrast with low-frequency, point measurement devices [58,59]. In this study, the flow metrics derived from the LLP were based on previous work comparing the sensor data to fish behaviour in a vertical slot fishway, where the most significant variables were the mean pressure, the mean front fluctuations, and the mean pressure asymmetry [60].…”

Fish Lateral Line Inspired Flow Sensors and Flow-aided Control: A Review

“…According to the characteristics of the fluid, the flows were classified by comparing the probability distribution of turbulent pressure fluctuation. The classification of flow fields is very important to the control and navigation of underwater vehicles [53] . [18] ,Chen et al…”

“…They put forward a fitted formula representing the relationship between the average pressure variance and the flow speed based on Bernoulli formula. Besides, they also reported that the flow direction could be detected because the pressure on the side which the probe turned [53]. (e) A 3D model of the carrier in Ref.…”

“…To make full use of the ALL, they reported on the implementation of a algorithm consisting of the template training approach and the modeling approach based on Minimum Mean-Squared Error (MMSE) algorithm in order to locate and track a vibrational dipole source [44] . Salumäe and Kruusmaa 2013 [51] 5 pressure sensors (Intersema MS5407-AM) Laboratory experiment Tuhtan et al 2018 [53] 11 pressure sensors (SM5420C-030-A-P-S) Laboratory experiment Liu et al 2019 [54] 23 pressure sensors (MS5803-07BA) Laboratory experiment…”

“…. (d) Illustration of the lateral line probe used for field measurements showing shape and sensor distribution in Ref [53]…”