saltylab-firmware/jetson/ros2_ws/src/saltybot_patrol

SaltyBot Patrol Mode (Issue #446)

Autonomous waypoint circuit with idle behaviors, person detection, and social integration.

Features

• Autonomous Navigation: Uses Nav2 /navigate_to_pose to visit waypoints in order
• Idle Behaviors: Pan-tilt sweeps and random greetings at each waypoint (10-30s)
• Person Detection Pause: Detects people → pauses patrol → enters social mode → resumes when they leave
• Battery Management: Automatically returns to dock at <25% battery
• Teleop Override: Can be interrupted by teleop joystick control
• Voice Commands: Start/stop patrol via voice ("patrol start", "patrol stop")
• Randomized Patrol: Waypoints visited in random order each patrol cycle
• State Publishing: Publishes /saltybot/patrol_state for monitoring

Architecture

Patrol State Machine:
  IDLE → NAVIGATE → IDLE_BEHAVIOR → (next waypoint)
                ↓
         [Person Detected]
                ↓
         PAUSE_PERSON → SOCIAL_MODE → back to NAVIGATE

  Battery < 25% → RETURN_TO_DOCK
  Voice/Teleop → IDLE

Usage

Start Patrol

ros2 launch saltybot_patrol patrol.launch.py

Or via voice:

"Hey SaltyBot, start patrol"

Stop Patrol

ros2 service call /patrol_control ... stop

Or via voice:

"Hey SaltyBot, stop patrol"

Configuration

Edit config/patrol_params.yaml:

patrol_waypoints:
  - name: "waypoint_1"
    x: 5.0
    y: 0.0
    yaw: 0.0  # radians
  - name: "waypoint_2"
    x: 3.0
    y: 5.0
    yaw: 1.57

Parameters:

• min_idle_time: Minimum pause at each waypoint (default: 10s)
• max_idle_time: Maximum pause at each waypoint (default: 30s)
• battery_dock_threshold: Battery level to trigger dock return (default: 25%)
• person_pause_timeout: How long to wait for person to leave (default: 30s)

Topics

Topic	Type	Description
/saltybot/patrol_state	String	Current patrol state + battery + waypoint
/saltybot/speech_text	String	Greetings spoken at waypoints
/saltybot/pan_tilt_cmd	String	Pan-tilt sweep commands
/saltybot/person_detections	Detection2DArray	Person detection input
/saltybot/teleop_cmd	String	Teleop override signals
/saltybot/voice_cmd	String	Voice command input

Monitoring

Check patrol state:

ros2 topic echo /saltybot/patrol_state

Expected output:

state:NAVIGATE,battery:85.5%,waypoint:2/5
state:IDLE_BEHAVIOR,battery:85.3%,waypoint:2/5
state:NAVIGATE,battery:84.8%,waypoint:3/5

Behaviors at Each Waypoint

1. Arrival: Stop at waypoint
2. Pan-Tilt Sweep: Look around the environment
3. Greeting: Speak random greeting
4. Pause: Wait 10-30 seconds
5. Move to Next: Navigate to next waypoint

Person Detection Integration

When a person is detected:

1. Patrol pauses
2. Robot faces the person (pan-tilt)
3. Enters social mode (greetings, conversation)
4. Waits for person to leave
5. Resumes patrol at current waypoint

Battery Management

• Continuous monitoring of battery level
• When battery < 25%: Immediately return to dock (0, 0)
• Pause patrol during charging
• Resume when battery > 80%

Teleop Override

• User can take control at any time
• Teleop takes priority over patrol
• Patrol pauses and enters idle
• Automatically resumes when control is released (if not manually stopped)

Limitations & Future

• Waypoint collision detection not implemented (uses Nav2 safety)
• No docking automation (manual charging)
• Pan-tilt and speech topics assumed to exist
• Person tracking limited to detection (no following)

Issue #446 Completion

✅ Autonomous waypoint circuit ✅ Idle behaviors (pan-tilt, greetings) ✅ Person detection pauses ✅ Battery monitoring & dock return ✅ Teleop override ✅ Voice commands ✅ Randomized waypoint order ✅ State publishing