EntrainOS: Custom Real-Time Operating System for the Mesh Network

ENTRAINOS — CUSTOM OPERATING SYSTEM

A real-time operating system purpose-built for collective brainwave synchronization across a decentralized mesh.

ARCHITECTURE: Two-Layer OS

LAYER 1: NODE OS (runs on each ESP32 headband) Based on FreeRTOS — proven RTOS with <1μs task switching

Four real-time tasks:

TASK 1: EEG_ACQUIRE (Priority: HIGHEST)

• SPI read from ADS1299 at 250Hz
• 4-channel data into ring buffer
• Hardware interrupt driven — never misses a sample
• Artifact rejection (blink/jaw clench detection)
• Execution time: <100 μs per sample

TASK 2: SIGNAL_PROCESS (Priority: HIGH)

• Sliding-window FFT: 256-point, every 100ms
• Band power extraction:

• Phase extraction at dominant frequency
• Coherence calculation vs. network reference
• Execution time: ~2ms per window

TASK 3: ENTRAIN_CONTROL (Priority: MEDIUM)

• Receives target frequency from network
• Generates entrainment waveform:

• Adaptive intensity based on EEG response:

• Never exceeds safety limits
• Execution time: <500 μs per update

TASK 4: MESH_COMM (Priority: MEDIUM)

• BLE mesh: broadcast phase packet every 50ms
• WiFi: send summary to relay every 500ms
• Receive group phase from mesh/relay
• Execute Kuramoto coupling algorithm
• Update target frequency for ENTRAIN_CONTROL
• Execution time: ~1ms per cycle

Memory usage: ~180 KB of 512 KB SRAM CPU usage: ~35% of dual-core capacity Leaves headroom for OTA updates and diagnostics.

LAYER 2: RELAY OS (runs on relay servers)

Based on Alpine Linux (~50 MB image) Custom name: EntrainRelay

Runs on ANY hardware:

• Raspberry Pi 4/5 ($35-80)
• Old laptop / desktop
• Cloud VM ($5/month DigitalOcean)
• Even a smartphone (Termux + Alpine)

Three services:

SERVICE 1: MESH BRIDGE

• Connects local BLE meshes to the internet
• WiFi access point for local nodes
• Aggregates phase data from local nodes
• Computes local group coherence

SERVICE 2: P2P RELAY (libp2p)

• Connects to other relays worldwide
• GossipSub protocol for phase propagation
• Kademlia DHT for peer discovery
• NO central server required
• Any relay can join/leave without disruption
• NAT traversal for home networks

SERVICE 3: ANALYTICS ENGINE

• Real-time coherence dashboard
• Network topology visualization
• Historical sync data (local only, privacy)
• Web UI accessible from any browser

Data sovereignty: ALL brainwave data stays local. Only phase angles and coherence scores cross the wire. Phase angles alone cannot reconstruct thoughts. This is privacy-by-design at the protocol level.