Lagoon 440 Sailing Application

A comprehensive cloud-based mobile application designed for Lagoon 440 catamaran sailing, providing sail configuration recommendations, navigation tracking, route management with real-time wind forecasts, weather monitoring, storm avoidance, and multi-user support.

• Configurable Monitoring: Check weather every X hours, forecast ahead X days
• Storm Detection: Automatic detection of storm systems (>40 kts)
• Squall Alerts: Identify sudden wind shifts and gusts
• High Wind/Wave Warnings: Customizable thresholds
• Daytime Arrival Planning: Ensures arrival during daylight hours (6 AM - 6 PM)
• Route Weather Analysis: Checks weather at waypoints and intermediate points
• Push & SMS Notifications: Critical alerts via push notifications and SMS
• Weather History: Track and compare forecast accuracy vs actual conditions

• Azure-Hosted API: Scalable cloud infrastructure
• User Authentication: Secure login system with JWT tokens
• Multi-User Support: Each user has their own routes and settings
• Route Sync: Routes saved to cloud, accessible from any device
• Profile Management: Customize notification preferences and monitoring settings

• Push Notifications: Real-time alerts via Expo notifications
• SMS Alerts: Critical weather alerts via SMS (Twilio integration)
• Configurable: Enable/disable by notification type
• Smart Routing: Only sends critical alerts via SMS to save costs

• GPS Integration: Automatic GPS coordinate tracking
• Wind Data:
  • Manual wind speed and true wind angle input
  • Integration with Windy.com API for real-time wind forecasts
  • Wave height information
  • Wind gust data
• Sail Configuration Recommendations:
  • Main Sail
  • Jib
  • Asymmetrical Spinnaker
  • Spinnaker
  • Code Zero
  • Storm Jib
• Speed Calculations: Based on Lagoon 440 polar diagrams
• Sailing Modes: Choose between Speed or Comfort sailing
• Tide/Current Input: Enter tide speed and direction for accurate course planning
• Navigation Recommendations: Real-time guidance to next waypoint including:
  • Distance to waypoint
  • Bearing and recommended heading
  • Estimated time of arrival
  • Sail configuration changes

• Waypoint Management:
  • Add waypoints manually with latitude/longitude
  • Edit existing waypoints
  • Delete waypoints
  • Reorder waypoints (move up/down)
• GPX File Support:
  • Import routes from GPX files
  • Export routes to GPX format
• Route Activation: Activate routes for navigation tracking
• Waypoint Tracking: Automatic detection of waypoint arrival

• Comprehensive Lagoon 440 Polar Data:
  • 6 sail configurations (Main+Jib, Main+Genoa, Main+Spinnaker, Asymmetrical, Code Zero, Storm)
  • 8+ wind speed curves per configuration
  • Full TWA range (40-180 degrees)
  • VMG (Velocity Made Good) calculations
• Performance Tracking:
  • Real-time target speed vs actual speed
  • Performance percentage display
  • Optimal angle recommendations
• Boat Specifications:
  • Complete technical details
  • Sail area information
  • Displacement and dimensions
• Multiple Formats:
  • Tabular view of polar data
  • JSON and CSV export
  • Import custom polar diagrams
• Cloud Storage:
  • Save custom polars to user account
  • Browse public polar diagrams
  • Clone and customize existing polars

• Node.js (v16 or higher)
• npm or yarn
• Expo CLI: npm install -g expo-cli
• iOS Simulator (Mac) or Android Emulator

1. Clone or download this repository

2. Single-command setup, build, and test:

npm run ci

3. (Optional) Use explicit commands:

npm run setup
npm run build:backend
npm run test:backend

4. Configure Windy.com API (Optional but Recommended):

   • Register for a free API key at https://api.windy.com/api-key
   • Open src/services/windyService.ts
   • Replace 'YOUR_WINDY_API_KEY' with your actual API key

5. Run backend tests (beta verification):

cd backend
npm test

6. Start the development server:

npm start

5. Run on your device:
   • iOS: Press i in the terminal or scan QR code with Expo Go app
   • Android: Press a in the terminal or scan QR code with Expo Go app
   • Web: Press w in the terminal (limited functionality)

1. Open the Sailing Tab
2. Enable Location: Grant location permissions when prompted
3. Update Location: Tap "Update Location" to get current GPS coordinates
4. Enter Sailing Data:
   • Wind speed (in knots)
   • True wind angle (0-360 degrees)
   • Boat heading and speed (auto-filled from GPS if available)
5. Optional - Get Wind Forecast:
   • Tap "Get Wind Forecast from Windy.com"
   • View wind speed, direction, gusts, and wave height
6. Optional - Enter Tide Data:
   • Input tide/current speed and direction
7. Select Sailing Mode:
   • Toggle between Comfort and Speed mode
8. View Recommendations:
   • See recommended sail configuration
   • View expected speed based on conditions

1. Open the Route Tab
2. Create a Route:
   • Enter a route name
   • Add waypoints manually by tapping "+ Add Waypoint"
   • Or import from a GPX file using "Import GPX"
3. Manage Waypoints:
   • Edit: Tap the ✎ icon
   • Delete: Tap the ✕ icon
   • Reorder: Use ↑ and ↓ buttons
4. Activate Route:
   • Tap "Activate Route for Navigation"
5. Navigate:
   • Switch to Sailing tab
   • View navigation recommendations to next waypoint
   • App automatically tracks waypoint arrivals

Import GPX:

1. Tap "Import GPX" in Route tab
2. Select a GPX file from your device
3. Waypoints will be loaded automatically

Export GPX:

1. Create or load a route with waypoints
2. Tap "Export GPX"
3. File will be saved to your device's documents directory
4. Share the file using your device's file manager

The app uses Lagoon 440 polar diagram data to recommend sail configurations based on:

• Wind speed and angle
• Sailing mode (speed vs comfort)
• Sea conditions

Configuration Rules:

• Storm Conditions (>35 kts): Deep reefed main + storm jib
• Heavy Wind (25-35 kts): Reefed main + reefed jib
• Moderate Wind (15-25 kts): Full main + jib, asymmetrical/spinnaker downwind
• Light Wind (8-15 kts): Full main + jib, or asymmetrical downwind
• Very Light Wind (<8 kts): Code Zero

Speed estimates are based on:

1. Lagoon 440 polar diagram interpolation
2. Sail configuration adjustments
3. Sailing mode multipliers
4. Tide/current calculations (when provided)

The app tracks:

• Distance traveled
• Average speed
• Waypoint arrivals (within 0.1 nautical miles)
• Course to next waypoint
• ETA based on current conditions

lagoon440-sailing-app/
├── App.tsx                          # Main app entry point with 3 tabs
├── src/
│   ├── screens/
│   │   ├── SailingScreen.tsx       # Main sailing screen
│   │   ├── RouteScreen.tsx         # Route management screen
│   │   └── PolarScreen.tsx         # Polar diagram viewer/editor
│   ├── components/
│   │   ├── ErrorPanel.tsx          # Error message display
│   │   ├── SailConfigDisplay.tsx   # Sail configuration display
│   │   └── PolarChart.tsx          # Polar diagram visualization
│   ├── services/
│   │   ├── windyService.ts         # Windy.com API integration
│   │   ├── navigationService.ts    # Navigation tracking logic
│   │   └── weatherMonitoringService.ts # Weather monitoring
│   ├── utils/
│   │   ├── sailingCalculations.ts  # Sailing math and recommendations
│   │   ├── gpxHandler.ts           # GPX file parsing and generation
│   │   └── polarImportExport.ts    # Polar diagram import/export
│   ├── types/
│   │   ├── sailing.ts              # TypeScript type definitions
│   │   └── polar.ts                # Polar diagram types
│   ├── data/
│   │   └── lagoon440Polar.ts       # Complete Lagoon 440 polar data
│   └── config/
│       └── api.ts                  # Backend API configuration
├── backend/
│   ├── src/
│   │   ├── server.ts               # Express server
│   │   ├── models/
│   │   │   ├── User.ts
│   │   │   ├── Route.ts
│   │   │   ├── WeatherHistory.ts
│   │   │   └── PolarDiagram.ts     # Polar storage model
│   │   ├── routes/
│   │   │   ├── auth.ts
│   │   │   ├── routes.ts
│   │   │   ├── weather.ts
│   │   │   ├── notifications.ts
│   │   │   └── polars.ts           # Polar API endpoints
│   │   └── middleware/
│   │       └── auth.ts
│   └── package.json
├── DEPLOYMENT.md                    # Complete deployment guide
├── POLAR_GUIDE.md                   # Polar diagram documentation
└── README.md

• React Native & Expo: Mobile app framework
• expo-location: GPS and location services
• expo-sensors: Device sensors (compass, accelerometer)
• expo-document-picker: File selection
• expo-file-system: File I/O operations
• @react-navigation: Tab navigation
• axios: HTTP requests for Windy.com API
• xml2js: GPX file parsing

The app integrates with Windy.com for weather forecasts. To configure:

1. Get API key from https://api.windy.com/api-key
2. Edit src/services/windyService.ts:

export function getWindyService(apiKey?: string): WindyService {
  if (!windyServiceInstance || apiKey) {
    windyServiceInstance = new WindyService({
      apiKey: apiKey || 'YOUR_API_KEY_HERE', // Replace with your key
    });
  }
  return windyServiceInstance;
}

Note: Without a valid API key, the app will show an error message when attempting to fetch wind forecasts, but all other features will work normally.

• Ensure location permissions are granted in device settings
• Check that location services are enabled on your device
• Try restarting the app

• Ensure the file is valid GPX format (XML)
• Check that the file contains waypoint, route, or track data
• Try a different GPX file

• Verify your Windy.com API key is configured correctly
• Check internet connection
• Ensure GPS coordinates are valid (not 0, 0)

• Clear Expo cache: expo start -c
• Reinstall dependencies: rm -rf node_modules && npm install
• Update Expo: npm install expo@latest

Potential features for future versions:

• Map view with route visualization
• Weather routing optimization
• Anchor alarm
• Logbook functionality
• Bluetooth integration with marine instruments
• AIS vessel tracking
• Offline maps and weather data
• Multi-day route planning
• Crew management features

This application is provided as-is for personal use. Ensure compliance with marine safety regulations and always use proper navigation equipment when sailing.

This application is intended as a supplementary navigation aid. Always use proper marine navigation equipment, charts, and safety procedures when sailing. The sail recommendations are based on general Lagoon 440 performance data and should be adjusted based on actual boat condition, crew experience, and sea state.

For issues or questions:

1. Check the Troubleshooting section above
2. Review Expo documentation: https://docs.expo.dev
3. Consult React Native documentation: https://reactnative.dev

• Lagoon 440 polar diagram data: Based on a published performance specifications
• Wind data: Powered by Windy.com API
• Built with React Native and Expo