Characterization of acoustic detection efficiency using a gliding robotic fish as a mobile receiver platform

Abstract Background Autonomous underwater vehicles (AUVs) and animal telemetry have become important tools for understanding the relationships between aquatic organisms and their environment, but more information is needed to guide the development and use of AUVs as effective animal tracking platforms. A forward-facing acoustic telemetry receiver (VR2Tx 69 kHz; VEMCO, Bedford, Nova Scotia) attached to a novel AUV (gliding robotic fish) was tested in a freshwater lake to (1) compare its detection efficiency (i.e., the probability of detecting an acoustic signal emitted by a tag) of acoustic tags (VEMCO model V8-4H 69 kHz) to stationary receivers and (2) determine if detection efficiency was related to distance between tag and receiver, direction of movement (toward or away from transmitter), depth, or pitch. Results Detection efficiency for mobile (robot-mounted) and stationary receivers were similar at ranges less than 300 m, on average across all tests, but detection efficiency for the mobile receiver decreased faster than for stationary receivers at distances greater than 300 m. Detection efficiency was higher when the robot was moving toward the transmitter than when moving away from the transmitter. Detection efficiency decreased with depth (surface to 4 m) when the robot was moving away from the transmitter, but depth had no significant effect on detection efficiency when the robot was moving toward the transmitter. Detection efficiency was higher when the robot was descending (pitched downward) than ascending (pitched upward) when moving toward the transmitter, but pitch had no significant effect when moving away from the transmitter. Conclusion Results suggested that much of the observed variation in detection efficiency is related to shielding of the acoustic signal by the robot body depending on the positions and orientation of the hydrophone relative to the transmitter. Results are expected to inform hardware, software, and operational changes to gliding robotic fish that will improve detection efficiency. Regardless, data on the size and shape of detection efficiency curves for gliding robotic fish will be useful for planning future missions and should be relevant to other AUVs for telemetry. With refinements, gliding robotic fish could be a useful platform for active tracking of acoustic tags in certain environments.

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Characterization of Highly Irradiated ALPIDE Silicon Sensors

Universe ◽

10.3390/universe5040091 ◽

2019 ◽

Vol 5 (4) ◽

pp. 91

Author(s):

Valentina Raskina ◽

Filip Křížek

Keyword(s):

Nuclear Physics ◽

Detection Efficiency ◽

Tracking System ◽

Physics Institute ◽

Total Ionization ◽

Silicon Sensors ◽

Active Pixel ◽

Academy Of Sciences

The ALICE (A Large Ion Collider Experiment) experiment at CERN will upgrade its Inner Tracking System (ITS) detector. The new ITS will consist of seven coaxial cylindrical layers of ALPIDE silicon sensors which are based on Monolithic Active Pixel Sensor (MAPS) technology. We have studied the radiation hardness of ALPIDE sensors using a 30 MeV proton beam provided by the cyclotron U-120M of the Nuclear Physics Institute of the Czech Academy of Sciences in Řež. In this paper, these long-term measurements will be described. After being irradiated up to the total ionization dose 2.7 Mrad and non-ionizing energy loss 2.7 × 10 13 1 MeV n eq · cm - 2 , ALPIDE sensors fulfill ITS upgrade project technical design requirements in terms of detection efficiency and fake-hit rate.

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Design, Modeling, and Experimental Drag Characterization of a Bio-Inspired, Shape-Adapting Underwater Vehicle

Volume 5A: 42nd Mechanisms and Robotics Conference ◽

10.1115/detc2018-85368 ◽

2018 ◽

Author(s):

Levi D. DeVries ◽

Michael D. M. Kutzer ◽

Rebecca E. Richmond ◽

Archie C. Bass

Keyword(s):

Spatial Scales ◽

Autonomous Underwater Vehicles ◽

Major Axis ◽

Underwater Vehicle ◽

Great Promise ◽

Hydrodynamic Drag ◽

Control Input ◽

Semi Major Axis ◽

Generative Modeling

Autonomous underwater vehicles (AUVs) have shown great promise in fulfilling surveillance, scavenging, and monitoring tasks, but can be hindered in expansive, cluttered or obstacle ridden environments. Traditional gliders and streamlined AUVs are designed for long term operational efficiency in expansive environments, but are hindered in cluttered spaces due to their shape and control authority; agile AUVs can penetrate cluttered or sensitive environments but are limited in operational endurance at large spatial scales. This paper presents the prototype testbed design, modeling, and experimental hydrodynamic drag characterization of a novel self-propelled underwater vehicle capable of actuating its shape morphology. The vehicle prototype incorporates flexible, buckled fiberglass ribs to ensure a rigid shape that can be actuated by modulating the length of the semi-major axis. Tools from generative modeling are used to represent the vehicle shape by using a single control input actuating the vehicles length-to-diameter ratio. By actuating the length and width characteristics of the vehicle’s shape to produce a desired drag profile, we derive the feasible speeds achievable by shape actuation control. Tow-tank experiments with an experimental proto-type suggest shape actuation can be used to manipulate the drag by a factor between 2.15 and 5.8 depending on the vehicle’s operating speed.

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Ekstraksi, Karakterisasi dan Uji Aktivitas Antioksidan Astaxanthin dari Produk Fermentasi Udang (Cincalok)

Jurnal Kelautan Tropis ◽

10.14710/jkt.v24i3.10497 ◽

2021 ◽

Vol 24 (3) ◽

pp. 311-322

Author(s):

Mauludia Mauludia ◽

Thamrin Usman ◽

Winda Rahmalia ◽

Dwi Imam Prayitno ◽

Siti Nani Nurbaeti

Keyword(s):

Antioxidant Activity ◽

High Pressure ◽

Liquid Chromatography ◽

High Pressure Liquid Chromatography ◽

Aquatic Organisms ◽

Dpph Method ◽

Wet Weight ◽

Tlc Analysis ◽

Layer Chromatography

Shrimp is one of the aquatic organisms that contain several active compounds, including astaxanthin. Cincalok is one of the fermented shrimp products containing astaxanthin. This study aims to determine the characteristics of astaxanthin extract from cincalok and its antioxidant activity. Extraction of astaxanthin from cincalok was carried out using the reflux method with acetone : cyclohexane (20:80 v/v) as a solvent. The identification and characterization of astaxanthin was carried out using thin-layer chromatography (TLC), UV-Vis spectrophotometry, and High-Pressure Liquid Chromatography (HPLC). Meanwhile, the antioxidant activity test was carried out using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method in one serial concentration (5; 15; 25 ppm). The results of TLC analysis showed that astaxanthin in cincalok extract has Rf value (0.32). The analysis using a UV-Vis spectrophotometer produced a spectrum with a maximum wavelength of 477 nm, which corresponds to the maximum wavelength of standard astaxanthin. The yield of astaxanthin extract from cincalok in this study was 1.47 mg/100 g wet weight. The chromatogram from the results of UHPLC analysis showed that the retention time of cincalok astaxanthin extract was 6.27 minutes with a purity of 18.03%. The antioxidant activity of cincalok astaxanthin extract was 568.32 ppm. Udang merupakan salah satu organisme air yang mengandung banyak senyawa aktif, termasuk astaxanthin. Cincalok merupakan salah satu produk hasil fermentasi udang yang mengandung astaxanthin. Penelitian ini bertujuan untuk mengetahui karakteristik ekstrak astaxanthin dari cincalok dan aktivitas antioksidannya. Ekstraksi astaxanthin dari cincalok menggunakan metode refluks dengan pelarut aseton:sikloheksan (20:80 v/v). Identifikasi dan karakterisasi astaxanthin dilakukan dengan menggunakan kromatografi lapis tipis (KLT), spektrofotometri UV-Vis, dan High Pressure Liquid Chromatography (HPLC). Sedangkan uji aktivitas antioksidan dilakukan menggunakan metode 1,1-difenil-2-pikrilhidrazil (DPPH) dengan memvariasikan konsentrasi larutan uji, yaitu 5; 15; 25 ppm. Hasil dari penelitian ini melaporkan astaxanthin pada ekstrak cincalok menunjukkan nilai Rf 0,32 pada kromatografi lapis tipis (KLT). Hasil analisis menggunakan spektrofotometer UV-Vis menghasilkan spektra dengan panjang gelombang maksimum 477 nm, yang sesuai dengan panjang gelombang maksimum astaxanthin standar. Randemen ekstrak astaxanthin dari cincalok pada penelitian ini adalah 1,47 mg/100 g berat basah. Kromatogram dari hasil analisis UHPLC menunjukkan waktu retensi ekstrak astaxanthin cincalok yaitu selama 6,27 menit dengan kemurnian sebesar 18,03%. Aktivitas antioksidan dari ekstrak astaxanthin cincalok diperoleh sebesar 568,32 ppm.

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Methods for estimating detection efficiency and tracking acoustic tags with mobile transect surveys

Journal of Fish Biology ◽

10.1111/j.1095-8649.2009.02428.x ◽

2009 ◽

Vol 75 (7) ◽

pp. 1773-1794 ◽

Cited By ~ 10

Author(s):

M. C. Melnychuk ◽

V. Christensen

Keyword(s):

Detection Efficiency ◽

Acoustic Tags

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Gas-Liquid Chromatography–Mass Spectrometry Characterization of Polychlorinated Biphenyls (Aroclors) and 36Cl-Labeling of Aroclors 1248 and 1254

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/54.4.801 ◽

1971 ◽

Vol 54 (4) ◽

pp. 801-807

Author(s):

David L Stalling ◽

James N Huckins

Keyword(s):

Mass Spectrometry ◽

Aquatic Organisms ◽

Sample Introduction ◽

Gas Liquid Chromatography ◽

Liquid Chromatography Mass Spectrometry ◽

Radioactive Materials ◽

Isomer Composition ◽

Temperature Programmed ◽

Uptake And Metabolism

Abstract The isomer composition of the Aroclor 1200 series was characterized by GLC-MS, using temperature programming and SE-30 support-coated, open-tubular capillary columns. A method is described for the preparation and purification of 36Cl-labeled Aroclors 1248 and 1254. Neutron irradiation of the commercial material was used to prepare the 36Cl-labeled material. Purification of the irradiated product was accomplished by silicic acid column chromatography. Yields of the purified product were between 63 and 99%, with no detectable alteration of the isomer composition; 10% of the 36C1 produced was associated with the unchanged PCB isomers and the remaining radioactivity was contained in polychlorinated terphenyls. The terphenyls were produced by irradiation polymerization, and they were easily separated from the PCB components. Mass spectrometry, utilizing either temperature programmed GLC or direct probe sample introduction, was used to characterize the irradiation products. The radioactive materials are being utilized in experiments to determine uptake and metabolism of PCB by aquatic organisms.

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Autonomous Charging for an Underwater Robotic Fish by Direct Contact

Volume 2: Mechatronics; Mechatronics and Controls in Advanced Manufacturing; Modeling and Control of Automotive Systems and Combustion Engines; Modeling and Validation; Motion and Vibration Control Applications; Multi-Agent and Networked Systems; Path Planning and Motion Control; Robot Manipulators; Sensors and Actuators; Tracking Control Systems; Uncertain Systems and Robustness; Unmanned, Ground and Surface Robotics; Vehicle Dynamic Controls; Vehicle Dynamics and Traffic Control ◽

10.1115/dscc2016-9779 ◽

2016 ◽

Author(s):

Paul Phamduy ◽

Jayhwan Cheong ◽

Maurizio Porfiri

Keyword(s):

Autonomous Navigation ◽

Direct Contact ◽

Autonomous Underwater Vehicles ◽

Robotic Fish ◽

Laboratory Research ◽

Free Swimming ◽

Charging Station ◽

Battery Capacity ◽

Series Of Experiments ◽

Field Deployment

The operation of autonomous underwater vehicles is often hindered by their battery capacity, limiting the duration of its use. Here, we propose an integrated solution for autonomous charging of a robotic fish via direct contact through a novel claw mechanism for docking guidance. To assist the robotic fish in the docking process, the system incorporates a charging station designed with form-fit claws. A controller is designed to monitor the battery level of the robotic fish during free swimming and coordinate the docking process with respect to the maneuvers of both the robot and form-fit claws. Upon recognizing a low battery level, the controller commands the robotic fish to begin the docking process, and video feedback from an overhead camera is used to inform the autonomous navigation toward the charging station. After reaching a battery level threshold, the robotic fish is then released back in the water and returns to free swimming until the battery is discharged again. Through a series of experiments, we demonstrate the possibility of prolonged operation, consisting of repeated cycles of autonomous charging. Our proposed charging method enables prolonged autonomous swimming with minimal human supervision, opening the door for new, transformative applications of robotic fish in laboratory research and field deployment.

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