AQUA-ECHO
NET
Bio-Acoustic Chitosan Mesh for Sustainable Capture Fisheries — a passive concept that explores how conventional fishing nets could become more acoustically visible to marine mammals without batteries or active acoustic emission.
Teknik Komputer — Universitas Serambi Mekkah
ACOUSTIC INTERFACE
FREQ. 20–150 kHz
STATUS: CONCEPT
THE OCEAN HAS A VISIBILITY PROBLEM.
When fishing gear becomes acoustically difficult to detect, unintended interactions can occur. AQUA-ECHO NET explores a material-first route toward stronger acoustic contrast.
From barely distinguishable gear to a more defined acoustic interface.
The project does not claim a validated reduction in bycatch. Instead, it proposes a testable engineering pathway: combine chitosan-based material with micro-spiral geometry, then characterize the resulting acoustic response in controlled conditions.
NUMBERS NEED CONTEXT.
These interface values are deliberately framed as illustrative or conceptual. They are not presented as completed experimental results.
Marine mammal bycatch — figure shown only as a commonly cited global discussion point, subject to source and period.
kHz biosonar frequency range used here as a conceptual design reference.
Powered acoustic emission in the proposed concept; passive material interaction is the design premise.
Chitosan is explored as a material route derived from chitin-rich shellfish processing residues.
FROM WASTE TO ACOUSTIC VISIBILITY.
SHELL WASTE
Shrimp and crab shell residues become a potential circular-material feedstock.
CHITOSAN EXTRACTION
Chitin-rich biomass is explored as a source for a chitosan-based coating system.
MICRO-SPIRAL
Spiral geometry becomes a controllable structural parameter for the acoustic interface.
COATED NET
The concept integrates the material layer with a conventional passive fishing-net architecture.
ACOUSTIC INTERACTION
Laboratory measurements would determine how geometry, frequency and coating properties influence reflection.
INSIDE THE MICRO-SPIRAL.
A conceptual cutaway of the proposed acoustic interaction layer. The visualization is procedural, not a measured microscopy image.
BIOSONAR → INTERFACE → SIGNAL.
The proposed mechanism is simple to explain, but deliberately leaves the performance question open for measurement.
MAKE THE HYPOTHESIS COMPUTABLE.
Acoustic impedance can be represented as density multiplied by sound speed. The following values are simplified concept parameters and require laboratory characterization.
Requires laboratory characterization.
REFLECTION COEFFICIENT
Simplified impedance model. Real-world performance depends on geometry, frequency, coating thickness, water conditions and material properties.
THREE DIFFERENT DESIGN LOGICS.
CONVENTIONAL NET
- Power requirement None
- Acoustic emission Passive / incidental
- Material approach Conventional polymer
- Detectability Variable
- Maintenance Standard gear care
- Circular material Not inherent
ACOUSTIC PINGER
- Power requirement Battery / powered
- Acoustic emission Active
- Material approach Electronic device
- Detectability Device-dependent
- Maintenance Battery / device
- Circular material Not inherent
AQUA-ECHO NET
- Power requirement 0 W concept
- Acoustic emission Designed passive
- Material approach Chitosan + micro-spiral
- Detectability To be characterized
- Maintenance Target: net-like workflow
- Circular material Shell-waste pathway
FROM SHELL WASTE TO MARINE INNOVATION.
LOOP
BATTERY-FREE
Designed without dependence on an active electronic acoustic source.
LOW MAINTENANCE
The concept aims to fit the operating logic of conventional passive net gear.
CIRCULAR MATERIAL
Explores a route for shellfish processing residues to become functional biomaterial.
DESIGNED FOR LOWER BYCATCH RISK.
Impact is framed as a design objective, not a measured outcome.
Marine Conservation
Explore whether stronger acoustic visibility can reduce unintended interactions with marine mammals.
Sustainable Fisheries
Preserve the passive nature of fishing gear while introducing a material-science intervention.
Circular Economy
Create a potential value pathway from shellfish processing residues to functional materials.
Small-Scale Fisher Adoption
Future validation must include usability, maintenance, cost and practical fishing workflows.
WHAT ARE WE TESTING?
Can micro-spiral chitosan structures increase acoustic reflection?
How does coating thickness affect frequency response?
Does the material remain mechanically durable in marine conditions?
Can the system reduce unintended marine mammal interactions?
Can shell waste become a viable circular material source?
FROM CONCEPT TO FIELD VALIDATION.
PHASE 01
MATERIAL FORMULATION
Characterize chitosan coating, thickness, durability and adhesion.
PHASE 02
ACOUSTIC LAB TEST
Measure acoustic reflection across relevant frequencies.
PHASE 03
HYDRODYNAMIC TEST
Evaluate mesh behavior, strength and coating durability.
PHASE 04
CONTROLLED FIELD TRIAL
Compare interaction rates against conventional nets under controlled protocols.
PHASE 05
FISHER ADOPTION
Assess usability, cost, maintenance and economic feasibility.
SEE THE SYSTEM IN CONTEXT.
SMALL-SCALE FISHERIES
Conceptual field scene · not a measured deployment.
THE CLAIMS STOP WHERE THE DATA STOPS.
Material acoustic properties, target strength, bycatch reduction performance and field cost estimates require controlled laboratory and field validation.
Established scientific concepts are separated from project-specific performance claims.
Illustrative numbers and design targets are labeled so they are not mistaken for experiments.
Future tests should characterize frequency response, durability, hydrodynamics and real-world interactions.