Miniature underwater animal tags and smart sensors for civil engineering applications

Abstract

This paper gives an overview of miniature underwater IoT devices recently developed for civil engineering applications: animal tags and underwater smart sensors. The PNNL (Pacific Northwest National Laboratory) fish tag is a newly developed injectable tag that uses acoustic telemetry with hydrophones, set up mostly around dams, to track juvenile salmon. This paper details the decode and detection algorithms that allows for better detection accuracy and range while keeping a low false alarm rate. In addition, three miniature underwater smart sensors are also introduced: the PNNL sensor fish and sensor fish mini, the University of New Hampshire smart grains, and the Lehigh smart pebble. All three sensing devices utilize IMUs (inertial measurement units) to track the acceleration, rotation, and/or water pressure. Speed and position are estimated from 3-axis accelerometer and gyro sensor measurements and the need for rigorous calibration is demonstrated. Finally, the field application examples for the fish tags and smart sensors are described.