ASG Client Architecture

Overview

The ASG Client is an Android application that runs on smart glasses, acting as the bridge between hardware capabilities and the MentraOS ecosystem.

System Architecture

┌─────────────────────────────────────────────────────────┐
│                    Smart Glasses Hardware                │
│  ┌─────────────┐  ┌──────────────┐  ┌───────────────┐  │
│  │   Camera    │  │     MCU      │  │   Bluetooth   │  │
│  │             │  │  (Buttons)   │  │     Chip      │  │
│  └──────┬──────┘  └──────┬───────┘  └───────┬───────┘  │
│         │                │                   │           │
└─────────┼────────────────┼───────────────────┼───────────┘
          │                │                   │
          ▼                ▼                   ▼
┌─────────────────────────────────────────────────────────┐
│                    ASG Client Service                    │
│  ┌─────────────┐  ┌──────────────┐  ┌───────────────┐  │
│  │   Camera    │  │   Command    │  │   Bluetooth   │  │
│  │   Manager   │  │   Parser     │  │   Manager     │  │
│  └──────┬──────┘  └──────┬───────┘  └───────┬───────┘  │
│         │                │                   │           │
│         └────────────────┴───────────────────┘           │
│                          │                               │
│                    ┌─────▼──────┐                        │
│                    │ AsgClient  │                        │
│                    │  Service   │                        │
│                    └─────┬──────┘                        │
└─────────────────────────┼───────────────────────────────┘
                          │
                          ▼ BLE
                    ┌───────────┐
                    │  Mobile   │
                    │    App    │
                    └─────┬─────┘
                          │
                          ▼ Internet
                    ┌───────────┐
                    │ MentraOS  │
                    │   Cloud   │
                    └───────────┘

Core Components

AsgClientService

The main Android service that coordinates all functionality:

public class AsgClientService extends Service {
    // Core managers
    private IBluetoothManager bluetoothManager;
    private INetworkManager networkManager;
    private MediaCaptureService mediaCaptureService;

    // Message processing
    private void processReceivedMessage(String message);
    private void parseK900Command(String command);

    // Hardware integration
    private void handleButtonPress(boolean isLongPress);
    private void sendBatteryStatus();
}

Manager Pattern

The client uses interface-based managers for device abstraction:

// Network Manager Interface
public interface INetworkManager {
    void setWifiEnabled(boolean enabled);
    void connectToWifi(String ssid, String password);
    boolean isConnectedToWifi();
    String getCurrentWifiSsid();
}

// Bluetooth Manager Interface
public interface IBluetoothManager {
    void initialize();
    void sendData(byte[] data);
    boolean isConnected();
    void setConnectionListener(ConnectionListener listener);
}

Factory Pattern

Managers are created via factories based on device type:

public class NetworkManagerFactory {
    public static INetworkManager create(Context context) {
        if (isK900Device()) {
            return new K900NetworkManager(context);
        } else if (hasSystemPermissions()) {
            return new SystemNetworkManager(context);
        } else {
            return new FallbackNetworkManager(context);
        }
    }
}

Message Flow

Incoming Messages (Phone → Glasses)

1. BLE Reception: BluetoothManager receives data
2. Parse & Route: AsgClientService processes JSON
3. Execute Command: Appropriate manager handles action
4. Send Response: Status sent back via BLE

Outgoing Messages (Glasses → Phone)

1. Event Occurs: Button press, status change, etc.
2. Format Message: Create JSON message
3. Send via BLE: BluetoothManager transmits
4. Phone Relay: Mobile app forwards to cloud

Command Processing

MCU Commands

Commands from the microcontroller (hardware events):

// Button press commands
"cs_pho" → Short camera button press (photo)
"cs_vdo" → Long camera button press (video)

// Other hardware commands
"hm_batv" → Battery status update
"cs_swst" → Swipe gesture

Cloud Commands

Commands from MentraOS Cloud (via phone):

{
  "type": "take_photo",
  "requestId": "uuid-1234"
}

{
  "type": "start_rtmp_stream",
  "rtmpUrl": "rtmp://server/live/key",
  "streamId": "uuid-5678"
}

Service Lifecycle

1. Service Start

   • Initialize managers
   • Setup BLE advertising/connection
   • Start monitoring hardware

2. Runtime Operation

   • Process incoming messages
   • Handle hardware events
   • Manage network state
   • Upload queued media

3. Service Stop

   • Clean up resources
   • Stop active streams
   • Save state for restart

Threading Model

• Main Thread: UI operations, service lifecycle
• BLE Thread: Bluetooth communication
• Network Thread: WiFi operations, uploads
• Camera Thread: Media capture operations

State Management

The service maintains state for:

• Connection status (BLE, WiFi)
• Active operations (streaming, recording)
• Hardware state (battery, temperature)
• Configuration (button modes, settings)

Error Handling

• Graceful Degradation: Fallback behaviors for failures
• Retry Logic: Automatic retry for network operations
• State Recovery: Restore after service restart
• User Feedback: Status messages via BLE