RHKEARTH
NRL PATENTS // INDEPENDENT COMMERCIALIZATION EVALUATION

Hear the field.
Resolve the direction.

The Navy patents describe compact particle-motion vector sensing for low-frequency direction of arrival. A microfabricated mesh prototype showed dipole-type directional response in air; RHKEARTH is evaluating whether the disclosed underwater architectures can become a practical maritime sensing product.

Review the technology →Run the demonstrator →

The underlying patents are U.S. Navy / NRL intellectual property. No patent ownership, license, Navy sponsorship or operational deployment is claimed by this project.

SEA SURFACE // ILLUSTRATIVE PATENT IN CONTEXT // UNDERSEADIRECTION GEOMETRY ONLY PATENT IN CONTEXT // TOWED-ARRAY APPLICATION PATENT IN CONTEXT // SHALLOW-WATER MOORING DUAL-USE EVALUATION // HARBOR PATENT IN CONTEXT // POSITIVELY BUOYANT AVS TOWER
PATENT IN CONTEXT // UNDERSEA
Platform context, sensor architecture, receiver path
Photos and video provide context only. The overlays show source-bearing geometry and patent-described architecture.
01 / 05
UnderseaPatent / platform context
TowedPatent-described application context
LittoralPatent-described mooring context
HarborCommercialization hypothesis
SonobuoyPatent-described AVS context
NRL patents evaluated
02
No ownership or license claimed
Prototype mesh OD
6 mm
Reported spider-web prototype
Prototype total fiber
≈2.7 m
Reported in the 6 mm geometry
Prototype fundamental
530 Hz
Reported for the first mesh prototype
01 // Technology

Low-frequency sensing, made local.

The architecture and mesh views keep reported measurements separate from calculations, estimates and schematic geometry.

FLOATING BASE

Floating-base embodiment

US11287508B2 describes a floating base carrying one or more flow meters, coupled by a retaining thread to an anchor.

Low-frequency acoustic field
Particle motion / relative flow
Micro-mesh or channel response
Displacement / flow-sensor readout
Directional vector information
MESH FLOW-SENSOR ELEMENTSTATIC PATENT-BASED EXHIBITNo performance simulation
Normalized mesh directivityR / Rmax = cos θAnalytical relationship relative to mesh normal.
Ideal square-mesh fiber lengthL_fiber = 2L² / dPatent scaling relation for the ideal square mesh.
Ideal square-mesh length gainL_fiber / L = 2L / dRelative to one cantilever of length L.
02 // Demonstrator

Move the source. Inspect the bearing geometry.

Choose a patent-described deployment and move a generic source around the sensor. The display shows direction geometry only and does not calculate sonar performance.

Model boundary: normalized 2-D direction geometry only. No physical range, source level, SNR, propagation loss, sensitivity, bearing error, classification or detection probability is calculated.

Patent concept demonstrator

Source-bearing geometry with patent-described deployment context.

Floating base / flow meters
NESW 315°GENERIC ACOUSTIC SOURCE
SENSOR → SOURCE BEARING
SOURCE → SENSOR PROPAGATION
03 // Applications

Defense first. Dual-use second.

Patent deployment concepts and RHKEARTH application ideas are labeled separately. The site does not claim customers, program-of-record status, detection range or fielded Navy use.

PATENT-DESCRIBED DEFENSE CONTEXTS

Moored, hull-mounted, towed and sonobuoy architectures

The specifications discuss shallow-water mooring, submarine/AUV hull mounting, neutrally buoyant towed arrays, positively buoyant sonobuoy use and external receiver/controller links.

EVALUATION PATHS

Ports, offshore systems and environmental observation

These are RHKEARTH application ideas, not patent deployment claims. They still require technical validation, customer demand and appropriate rights.