Convoy Mode

A distributed formation system enabling multiple seasteads to travel as a coordinated fleet with shared situational awareness.

Designed for 3–50+ unit fleets

CORE CONCEPT

Fixed Relative Positioning

Seasteads maintain precise grid positions relative to each other using moving-base RTK GPS, enabling coordinated movement and shared sensor fusion.

Autopilot Integration

Automatic position locking when within 0.5 grid spacing

Shared Perception

Parallax-based object ranging across the fleet

Example 3×3 Grid Formation

50m spacing

All units maintain synchronized heading and speed via distributed consensus

LOCAL MESH NETWORK

Recommended Communications Stack

Primary: Wi-Fi 6 (802.11ax)

5 GHz band

Typical Range 1.2 – 2.8 km

Data Rate 300–850 Mbps

Hardware Cost $180–320 per unit

Recommended Hardware

• MikroTik LHG XL 5 ac
• Ubiquiti NanoBeam 5AC Gen2
• 4× 24 dBi directional antennas

Mesh Software Stack

BATMAN-adv

Layer 2 mesh (recommended)

OLSRv2

Alternative routing

Application Layer

• MQTT broker mesh (Eclipse Mosquitto)
• Custom ROS 2 topic distribution
• Shared object database via protobuf

Backup / Long-range

LoRaWAN (915 MHz)

5–12 km range at 0.5–20 kbps for critical telemetry and emergency coordination.

Total estimated comms cost per seastead: $420–650

HYDRODYNAMICS

Wave Energy Dispersion in Convoy

Each NACA 0030 foil leg acts as a wave energy dissipator. With the convoy traveling in a tight grid formation, the foils create a distributed array that can produce localized wave interference patterns.

Key Observations

• Destructive interference can reduce wave amplitude by 15–35% in central convoy positions
• Foil spacing of 40–60m appears optimal for typical ocean wavelengths
• Moving formation creates a "wave shadow" effect for trailing units

Preliminary Simulation Result

22%

Average reduction in significant wave height for inner positions (12+ units)

Requires further CFD modeling with actual foil geometry and spacing.

Convoy Mode Requirements

Positioning

Moving-base RTK GPS (u-blox F9P or equivalent)
Sub-2cm relative accuracy
Heading from dual-antenna RTK

Perception

4× 4K marine cameras per seastead
Shared object tracking database
Parallax distance estimation engine

Autopilot

Distributed consensus protocol
Formation control algorithms
Automatic join/leave handshake

All systems leverage the existing triple-redundant power architecture and Starlink connectivity.

Seastead Convoy Mode Concept • All dimensions compatible with 45ft High Cube container

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