Healthcare EEG System - Docker Application

ROS2-based EEG data acquisition, preprocessing, and real-time visualization using Docker

🚀 Quick Start

Prerequisites

• Docker & Docker Compose
• ROS2 Jazzy
• Python 3.10+

1. Configure Credentials

Create the InfluxDB credential file:

nano env_credentials/.env.influxdb

Required credentials:

INFLUXDB_ADMIN_USERNAME=admin
INFLUXDB_ADMIN_PASSWORD=YourSecurePassword123!
INFLUXDB_ORG=healthcare
INFLUXDB_BUCKET=eeg_data
INFLUXDB_ADMIN_TOKEN=your-secure-token-2026!
INFLUXDB_RETENTION_MINUTES=5

2. Generate Dashboard

python3 nodes/visualization/dashboard/generate_dashboard.py

3. Start Docker Services

docker-compose up -d

Services started:

• InfluxDB on port 8086 (time-series database)
• Nginx on port 8080 (web dashboard)

4. Access Dashboard

Open: http://localhost:8080

---

🏗️ Architecture

┌─────────────────────────────────────────────────────────┐
│                    ROS2 Native Layer                     │
│                                                          │
│  EEG Simulator (150 Hz)                                 │
│         ↓                                                │
│  Preprocessing (0.5-45 Hz bandpass, CAR)                │
│         ↓                                                │
│  InfluxDB Bridge (writes per-sample points)             │
└─────────────────────────────────────────────────────────┘
                            ↓
┌─────────────────────────────────────────────────────────┐
│                   Docker Container Layer                 │
│                                                          │
│  ┌──────────────┐         ┌─────────────────┐          │
│  │InfluxDB 2.8  │  ←───   │  Nginx (Alpine) │          │
│  │Port 8086     │         │  Port 8080      │          │
│  └──────────────┘         └─────────────────┘          │
│                                   ↓                      │
│                         Web Dashboard (poll 50ms)       │
│                    http://localhost:8080                │
└─────────────────────────────────────────────────────────┘

Data Flow

1. EEG Simulator generates 4-channel data at 150 Hz
2. Preprocessor filters and applies CAR (Common Average Reference)
3. InfluxDB Bridge writes per-sample values to InfluxDB
4. Web Dashboard queries InfluxDB and visualizes in real-time

---

📊 System Components

ROS2 Nodes (Native)

Node	Topic	Description
eeg_simulator	/eeg/raw	150 Hz 4-channel EEG generation
eeg_preprocessing	/eeg/processed	0.5-45 Hz bandpass + CAR
eeg_influxdb_bridge	-	Writes to InfluxDB for web viz Auto-cleanup: Keeps only last 5 minutes

Docker Services

Service	Port	Purpose
influxdb	8086	Time-series database
nginx	8080, 8443	Web server for dashboard

---

🎮 Usage

Start Full System (Production: simulator + web dashboard)

# Start Docker containers + simulator + preprocessing + InfluxDB bridge
USE_INFLUXDB=1 ./launch/start.sh

View Dashboard

Open browser: http://localhost:8080

Features:

• Real-time 4-channel EEG visualization
• Raw and preprocessed overlays
• Polling 50ms (best-effort rendering)

Stop System

# Stop Docker containers
docker-compose down

# Stop ROS2 nodes with Ctrl+C in each terminal

---

🔧 Configuration

Environment Variables

Edit env_credentials/.env.influxdb:

# InfluxDB Configuration
INFLUXDB_ADMIN_USERNAME=admin
INFLUXDB_ADMIN_PASSWORD=YourPassword
INFLUXDB_ORG=healthcare
INFLUXDB_BUCKET=eeg_data
INFLUXDB_ADMIN_TOKEN=your-token

# Data Retention (Production - prevents database from filling up)
INFLUXDB_RETENTION_MINUTES=5  # Auto-delete data older than 5 minutes

# InfluxDB Connection (for bridge)
INFLUXDB_URL=http://localhost:8086

Docker Ports

Edit docker-compose.yml to change ports:

nginx:
  ports:
    - "8080:80"   # HTTP: Change left side
    - "8443:443"  # HTTPS: Change left side

---

📁 Project Structure

.
├── docker-compose.yml              # Docker services configuration
├── env_credentials/                # Credential files (git-ignored)
│   └── .env.influxdb                # InfluxDB credentials
├── nodes/
│   ├── data_acquisition/
│   │   └── eeg_simulator.py        # 150 Hz EEG simulator
│   ├── preprocessing/
│   │   └── eeg_preprocessing.py    # Signal processing
│   ├── saver/
│   │   └── eeg_influxdb_bridge.py  # InfluxDB writer
│   └── visualization/
│       ├── generate_dashboard.py   # Dashboard generator
│       ├── influxdb_realtime_dashboard.template.html
│       └── influxdb_realtime_dashboard.html
├── nginx/                           # Nginx configuration
├── logs/                            # Node logs
└── eeg_data/                        # Recorded data (optional)

---

🛠️ Development

Regenerate Dashboard

After changing credentials:

python3 nodes/visualization/dashboard/generate_dashboard.py
docker restart healthcare-nginx

View Logs

# Docker logs
docker logs influxdb -f
docker logs healthcare-nginx -f

# ROS2 node logs
tail -f logs/eeg_simulator.log
tail -f logs/eeg_preprocessing.log
tail -f logs/eeg_influxdb_bridge.log

Check Docker Status

docker ps
docker-compose ps

---

🔐 Security

Best Practices

1. Change default credentials in env_credentials/.env.influxdb
2. Use strong passwords (min 12 characters, special chars)
3. Don't commit env_credentials/.env.influxdb to git (already in .gitignore)
4. Use HTTPS in production (configure nginx/ssl/)

Production Deployment

For production, the dashboard automatically adapts to your server:

// Dashboard detects server IP automatically
const INFLUXDB_URL = window.location.protocol + '//' + window.location.host;

Access: http://your-server-ip:8080
InfluxDB connection: http://your-server-ip:8086

---

📈 Performance

• Sampling Rate: 150 Hz (realistic clinical EEG)
• Dashboard Polling: 50ms (best-effort rendering)
• Data Window: 2 seconds (300 samples)
• Channels: 4 (FP1, FP2, F3, F4)
• Latency: < 10ms typical

---

🐛 Troubleshooting

Dashboard shows no data

# Check if InfluxDB is running
curl http://localhost:8086/health

# Check bridge logs
tail -f logs/eeg_influxdb_bridge.log

# Restart bridge
pkill -f eeg_influxdb_bridge
python3 nodes/saver/eeg_influxdb_bridge.py

Docker container not starting

# Check logs
docker logs influxdb
docker logs healthcare-nginx

# Restart containers
docker-compose restart

# Rebuild if needed
docker-compose down
docker-compose up -d

Port already in use

# Check what's using port 8086 or 8080
sudo netstat -tulpn | grep -E '8080|8086'

# Stop conflicting service or change port in docker-compose.yml

---

📝 License

This project is part of the healthcare_ros system developed by SCAI-Lab.

---

🚀 Summary

This is a pure Docker application for EEG data visualization:

1. Docker Compose manages InfluxDB + Nginx
2. ROS2 nodes run natively and write to InfluxDB
3. Web dashboard served by Nginx at http://localhost:8080
4. No manual installation of InfluxDB or Nginx required

Just configure env_credentials/.env.influxdb, run USE_INFLUXDB=1 ./launch/start.sh, and open the dashboard!