Merge remote-tracking branch 'origin/sl-jetson/here4-dronecan-driver'

# Conflicts:
#	jetson/ros2_ws/src/saltybot_dronecan_gps/package.xml
#	jetson/ros2_ws/src/saltybot_dronecan_gps/setup.cfg
#	jetson/ros2_ws/src/saltybot_dronecan_gps/setup.py

jetson/docker-compose.yml

@@ -97,11 +97,7 @@ services:
           rgb_camera.profile:=640x480x30
       "
 
-<<<<<<< HEAD
+  # ── ESP32-S3 bridge node (bidirectional serial<->ROS2) ───────────────────────
-  # ── ESP32 bridge node (bidirectional serial<->ROS2) ────────────────────────
-=======
-  # ── ESP32-S3 bridge node (bidirectional serial<->ROS2) ────────────────────────
->>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
   esp32-bridge:
     image: saltybot/ros2-humble:jetson-orin
     build:
@@ -212,13 +208,8 @@ services:
       "
 
 
-<<<<<<< HEAD
+  # -- Remote e-stop bridge (MQTT over 4G -> ESP32-S3 CDC) ---------------------
-  # -- Remote e-stop bridge (MQTT over 4G -> ESP32 CDC) ----------------------
-  # Subscribes to saltybot/estop MQTT topic. {"kill":true} -> 'E\r\n' to ESP32 BALANCE.
-=======
-  # -- Remote e-stop bridge (MQTT over 4G -> ESP32-S3 CDC) ----------------------
   # Subscribes to saltybot/estop MQTT topic. {"kill":true} -> 'E\r\n' to ESP32-S3.
->>>>>>> 291dd68 (feat: remove all STM32/Mamba/BlackPill references — ESP32-S3 only)
   # Cellular watchdog: 5s MQTT drop in AUTO mode -> 'F\r\n' (ESTOP_CELLULAR_TIMEOUT).
   remote-estop:
     image: saltybot/ros2-humble:jetson-orin
@@ -366,6 +357,50 @@ services:
       "
 
 
+  # ── Here4 DroneCAN GPS + NTRIP RTK client ────────────────────────────────
+  # Issue #725 — CubePilot Here4 RTK GPS via DroneCAN (1Mbps, SocketCAN)
+  # Start: docker compose up -d here4-gps
+  # Monitor fix: docker compose exec here4-gps ros2 topic echo /gps/rtk_status
+  # Configure NTRIP: set NTRIP_MOUNT, NTRIP_USER, NTRIP_PASSWORD env vars
+  here4-gps:
+    image: saltybot/ros2-humble:jetson-orin
+    build:
+      context: .
+      dockerfile: Dockerfile
+    container_name: saltybot-here4-gps
+    restart: unless-stopped
+    runtime: nvidia
+    network_mode: host
+    depends_on:
+      - saltybot-nav2
+    environment:
+      - ROS_DOMAIN_ID=42
+      - RMW_IMPLEMENTATION=rmw_cyclonedds_cpp
+      # NTRIP credentials — set these in your .env or override at runtime
+      - NTRIP_MOUNT=${NTRIP_MOUNT:-}
+      - NTRIP_USER=${NTRIP_USER:-}
+      - NTRIP_PASSWORD=${NTRIP_PASSWORD:-}
+    volumes:
+      - ./ros2_ws/src:/ros2_ws/src:rw
+      - ./config:/config:ro
+    devices:
+      - /dev/can0:/dev/can0
+    cap_add:
+      - NET_ADMIN    # needed for SocketCAN ip link set can0 up inside container
+    command: >
+      bash -c "
+        source /opt/ros/humble/setup.bash &&
+        source /ros2_ws/install/local_setup.bash 2>/dev/null || true &&
+        pip install python-dronecan --quiet 2>/dev/null || true &&
+        ros2 launch saltybot_dronecan_gps here4_gps.launch.py
+          can_interface:=can0
+          can_bitrate:=1000000
+          ntrip_caster:=rtk2go.com
+          ntrip_mount:=${NTRIP_MOUNT:-}
+          ntrip_user:=${NTRIP_USER:-}
+          ntrip_password:=${NTRIP_PASSWORD:-}
+      "
+
 volumes:
   saltybot-maps:
     driver: local

jetson/ros2_ws/src/saltybot_dronecan_gps/config/dronecan_gps_params.yaml

@@ -0,0 +1,9 @@
+# dronecan_gps_params.yaml — CubePilot Here4 DroneCAN GPS driver defaults
+# Issue: https://gitea.vayrette.com/seb/saltylab-firmware/issues/725
+
+dronecan_gps:
+  ros__parameters:
+    can_interface:    "can0"
+    can_bitrate:      1000000   # Here4 default: 1Mbps DroneCAN
+    node_id:          127       # DroneCAN local node ID (GPS driver)
+    publish_compass:  true      # publish MagneticFieldStrength if available

jetson/ros2_ws/src/saltybot_dronecan_gps/launch/here4_gps.launch.py

@@ -0,0 +1,110 @@
+"""
+here4_gps.launch.py — CubePilot Here4 RTK GPS full stack
+Issue: https://gitea.vayrette.com/seb/saltylab-firmware/issues/725
+
+Launches:
+  - dronecan_gps_node   (saltybot_dronecan_gps)
+  - ntrip_client_node   (saltybot_ntrip_client)
+
+Usage (minimal):
+  ros2 launch saltybot_dronecan_gps here4_gps.launch.py \\
+    ntrip_mount:=RTCM3_GENERIC ntrip_user:=you@email.com
+
+Full options:
+  ros2 launch saltybot_dronecan_gps here4_gps.launch.py \\
+    can_interface:=can0 \\
+    can_bitrate:=1000000 \\
+    ntrip_caster:=rtk2go.com \\
+    ntrip_port:=2101 \\
+    ntrip_mount:=MYBASE \\
+    ntrip_user:=you@email.com \\
+    ntrip_password:=secret
+"""
+
+import os
+
+from ament_index_python.packages import get_package_share_directory
+from launch import LaunchDescription
+from launch.actions import DeclareLaunchArgument
+from launch.substitutions import LaunchConfiguration
+from launch_ros.actions import Node
+
+
+def generate_launch_description() -> LaunchDescription:
+    gps_cfg = os.path.join(
+        get_package_share_directory('saltybot_dronecan_gps'),
+        'config', 'dronecan_gps_params.yaml',
+    )
+    ntrip_cfg = os.path.join(
+        get_package_share_directory('saltybot_ntrip_client'),
+        'config', 'ntrip_params.yaml',
+    )
+
+    return LaunchDescription([
+        # ── Shared CAN args ───────────────────────────────────────────────────
+        DeclareLaunchArgument(
+            'can_interface', default_value='can0',
+            description='SocketCAN interface name',
+        ),
+        DeclareLaunchArgument(
+            'can_bitrate', default_value='1000000',
+            description='CAN bus bitrate — Here4 default is 1000000 (1 Mbps)',
+        ),
+
+        # ── NTRIP args ────────────────────────────────────────────────────────
+        DeclareLaunchArgument(
+            'ntrip_caster', default_value='rtk2go.com',
+            description='NTRIP caster hostname',
+        ),
+        DeclareLaunchArgument(
+            'ntrip_port', default_value='2101',
+            description='NTRIP caster port',
+        ),
+        DeclareLaunchArgument(
+            'ntrip_mount', default_value='',
+            description='NTRIP mount point (REQUIRED)',
+        ),
+        DeclareLaunchArgument(
+            'ntrip_user', default_value='',
+            description='NTRIP username (rtk2go.com requires email address)',
+        ),
+        DeclareLaunchArgument(
+            'ntrip_password', default_value='',
+            description='NTRIP password',
+        ),
+
+        # ── DroneCAN GPS node ─────────────────────────────────────────────────
+        Node(
+            package='saltybot_dronecan_gps',
+            executable='dronecan_gps_node',
+            name='dronecan_gps',
+            output='screen',
+            parameters=[
+                gps_cfg,
+                {
+                    'can_interface': LaunchConfiguration('can_interface'),
+                    'can_bitrate':   LaunchConfiguration('can_bitrate'),
+                },
+            ],
+        ),
+
+        # ── NTRIP client node ─────────────────────────────────────────────────
+        Node(
+            package='saltybot_ntrip_client',
+            executable='ntrip_client_node',
+            name='ntrip_client',
+            output='screen',
+            parameters=[
+                ntrip_cfg,
+                {
+                    'can_interface':  LaunchConfiguration('can_interface'),
+                    'can_bitrate':    LaunchConfiguration('can_bitrate'),
+                    'ntrip_caster':   LaunchConfiguration('ntrip_caster'),
+                    'ntrip_port':     LaunchConfiguration('ntrip_port'),
+                    'ntrip_mount':    LaunchConfiguration('ntrip_mount'),
+                    'ntrip_user':     LaunchConfiguration('ntrip_user'),
+                    'ntrip_password': LaunchConfiguration('ntrip_password'),
+                },
+            ],
+        ),
+    ])

jetson/ros2_ws/src/saltybot_dronecan_gps/resource/saltybot_dronecan_gps

@@ -0,0 +1 @@
+saltybot_dronecan_gps

jetson/ros2_ws/src/saltybot_dronecan_gps/saltybot_dronecan_gps/dronecan_gps_node.py

@@ -0,0 +1,204 @@
+#!/usr/bin/env python3
+"""
+dronecan_gps_node.py — DroneCAN GPS driver for CubePilot Here4 RTK
+Issue: https://gitea.vayrette.com/seb/saltylab-firmware/issues/725
+
+Subscribes to:
+  uavcan.equipment.gnss.Fix2            (msg ID 1063) — position + fix status
+  uavcan.equipment.ahrs.MagneticFieldStrength          — compass (optional)
+
+Publishes:
+  /gps/fix        sensor_msgs/NavSatFix
+  /gps/vel        geometry_msgs/TwistStamped
+  /gps/rtk_status std_msgs/String
+
+DroneCAN fix_type → sensor_msgs status mapping:
+  0 = NO_FIX     → STATUS_NO_FIX  (-1)
+  1 = TIME_ONLY  → STATUS_NO_FIX  (-1)
+  2 = 2D_FIX    → STATUS_FIX      (0)
+  3 = 3D_FIX    → STATUS_FIX      (0)
+  4 = DGPS       → STATUS_SBAS_FIX (1)
+  5 = RTK_FLOAT  → STATUS_GBAS_FIX (2)
+  6 = RTK_FIXED  → STATUS_GBAS_FIX (2)
+"""
+
+import math
+import threading
+
+import rclpy
+from rclpy.node import Node
+from rclpy.qos import QoSProfile, ReliabilityPolicy, HistoryPolicy
+
+from sensor_msgs.msg import NavSatFix, NavSatStatus
+from geometry_msgs.msg import TwistStamped
+from std_msgs.msg import String
+
+try:
+    import dronecan
+except ImportError:
+    dronecan = None
+
+_SENSOR_QOS = QoSProfile(
+    reliability=ReliabilityPolicy.BEST_EFFORT,
+    history=HistoryPolicy.KEEP_LAST,
+    depth=5,
+)
+
+# DroneCAN fix_type → (NavSatStatus.status, rtk_label)
+_FIX_MAP = {
+    0: (NavSatStatus.STATUS_NO_FIX,   'NO_FIX'),
+    1: (NavSatStatus.STATUS_NO_FIX,   'TIME_ONLY'),
+    2: (NavSatStatus.STATUS_FIX,      '2D_FIX'),
+    3: (NavSatStatus.STATUS_FIX,      '3D_FIX'),
+    4: (NavSatStatus.STATUS_SBAS_FIX, 'DGPS'),
+    5: (NavSatStatus.STATUS_GBAS_FIX, 'RTK_FLOAT'),
+    6: (NavSatStatus.STATUS_GBAS_FIX, 'RTK_FIXED'),
+}
+
+
+class DroneCanGpsNode(Node):
+    def __init__(self) -> None:
+        super().__init__('dronecan_gps')
+
+        self.declare_parameter('can_interface', 'can0')
+        self.declare_parameter('can_bitrate', 1000000)
+        self.declare_parameter('node_id', 127)          # DroneCAN local node ID
+        self.declare_parameter('publish_compass', True)
+
+        self._iface = self.get_parameter('can_interface').value
+        self._bitrate = self.get_parameter('can_bitrate').value
+        self._node_id = self.get_parameter('node_id').value
+        self._publish_compass = self.get_parameter('publish_compass').value
+
+        self._fix_pub = self.create_publisher(NavSatFix, '/gps/fix', _SENSOR_QOS)
+        self._vel_pub = self.create_publisher(TwistStamped, '/gps/vel', _SENSOR_QOS)
+        self._rtk_pub = self.create_publisher(String, '/gps/rtk_status', 10)
+
+        if dronecan is None:
+            self.get_logger().error(
+                'python-dronecan not installed. '
+                'Run: pip install python-dronecan'
+            )
+            return
+
+        self._lock = threading.Lock()
+        self._dc_node = None
+        self._spin_thread = threading.Thread(
+            target=self._dronecan_spin, daemon=True
+        )
+        self._spin_thread.start()
+        self.get_logger().info(
+            f'DroneCanGpsNode started — interface={self._iface} '
+            f'bitrate={self._bitrate}'
+        )
+
+    # ── DroneCAN spin (runs in background thread) ─────────────────────────────
+
+    def _dronecan_spin(self) -> None:
+        try:
+            self._dc_node = dronecan.make_node(
+                self._iface,
+                node_id=self._node_id,
+                bitrate=self._bitrate,
+            )
+            self._dc_node.add_handler(
+                dronecan.uavcan.equipment.gnss.Fix2,
+                self._on_fix2,
+            )
+            if self._publish_compass:
+                self._dc_node.add_handler(
+                    dronecan.uavcan.equipment.ahrs.MagneticFieldStrength,
+                    self._on_mag,
+                )
+            self.get_logger().info(
+                f'DroneCAN node online on {self._iface}'
+            )
+            while rclpy.ok():
+                self._dc_node.spin(timeout=0.1)
+        except Exception as exc:
+            self.get_logger().error(f'DroneCAN spin error: {exc}')
+
+    # ── Message handlers ──────────────────────────────────────────────────────
+
+    def _on_fix2(self, event) -> None:
+        msg = event.message
+        now = self.get_clock().now().to_msg()
+
+        fix_type = int(msg.fix_type)
+        nav_status, rtk_label = _FIX_MAP.get(
+            fix_type, (NavSatStatus.STATUS_NO_FIX, 'UNKNOWN')
+        )
+
+        # NavSatFix
+        fix = NavSatFix()
+        fix.header.stamp = now
+        fix.header.frame_id = 'gps'
+        fix.status.status = nav_status
+        fix.status.service = NavSatStatus.SERVICE_GPS
+
+        fix.latitude = math.degrees(msg.latitude_deg_1e8 * 1e-8)
+        fix.longitude = math.degrees(msg.longitude_deg_1e8 * 1e-8)
+        fix.altitude = msg.height_msl_mm * 1e-3  # mm → m
+
+        # Covariance from position_covariance if available, else diagonal guess
+        if hasattr(msg, 'position_covariance') and len(msg.position_covariance) >= 9:
+            fix.position_covariance = list(msg.position_covariance)
+            fix.position_covariance_type = NavSatFix.COVARIANCE_TYPE_FULL
+        else:
+            h_var = (msg.horizontal_pos_accuracy_m_1e2 * 1e-2) ** 2 \
+                if hasattr(msg, 'horizontal_pos_accuracy_m_1e2') else 4.0
+            v_var = (msg.vertical_pos_accuracy_m_1e2 * 1e-2) ** 2 \
+                if hasattr(msg, 'vertical_pos_accuracy_m_1e2') else 4.0
+            fix.position_covariance = [
+                h_var, 0.0,   0.0,
+                0.0,   h_var, 0.0,
+                0.0,   0.0,   v_var,
+            ]
+            fix.position_covariance_type = NavSatFix.COVARIANCE_TYPE_DIAGONAL_KNOWN
+
+        self._fix_pub.publish(fix)
+
+        # TwistStamped velocity
+        if hasattr(msg, 'ned_velocity'):
+            vel = TwistStamped()
+            vel.header.stamp = now
+            vel.header.frame_id = 'gps'
+            vel.twist.linear.x = float(msg.ned_velocity[0])  # North m/s
+            vel.twist.linear.y = float(msg.ned_velocity[1])  # East  m/s
+            vel.twist.linear.z = float(msg.ned_velocity[2])  # Down  m/s (ROS: up+)
+            self._vel_pub.publish(vel)
+
+        # RTK status string
+        rtk_msg = String()
+        rtk_msg.data = rtk_label
+        self._rtk_pub.publish(rtk_msg)
+
+        self.get_logger().debug(
+            f'Fix2: {fix.latitude:.6f},{fix.longitude:.6f} '
+            f'alt={fix.altitude:.1f}m status={rtk_label}'
+        )
+
+    def _on_mag(self, event) -> None:
+        # Compass data logged; extend to publish /imu/mag if needed
+        msg = event.message
+        self.get_logger().debug(
+            f'Mag: {msg.magnetic_field_ga[0]:.3f} '
+            f'{msg.magnetic_field_ga[1]:.3f} '
+            f'{msg.magnetic_field_ga[2]:.3f} Ga'
+        )
+
+
+def main(args=None) -> None:
+    rclpy.init(args=args)
+    node = DroneCanGpsNode()
+    try:
+        rclpy.spin(node)
+    except KeyboardInterrupt:
+        pass
+    finally:
+        node.destroy_node()
+        rclpy.shutdown()
+
+
+if __name__ == '__main__':
+    main()

jetson/ros2_ws/src/saltybot_ntrip_client/config/ntrip_params.yaml

@@ -0,0 +1,18 @@
+# ntrip_params.yaml — NTRIP client configuration for Here4 RTK corrections
+# Issue: https://gitea.vayrette.com/seb/saltylab-firmware/issues/725
+#
+# Override at launch:
+#   ros2 launch saltybot_dronecan_gps here4_gps.launch.py \
+#     ntrip_mount:=MYBASE ntrip_user:=user ntrip_password:=pass
+
+ntrip_client:
+  ros__parameters:
+    ntrip_caster:     "rtk2go.com"
+    ntrip_port:       2101
+    ntrip_mount:      ""           # REQUIRED — set your mount point
+    ntrip_user:       ""           # empty = anonymous (rtk2go requires email)
+    ntrip_password:   ""
+    can_interface:    "can0"
+    can_bitrate:      1000000
+    can_node_id:      126          # DroneCAN local node ID (NTRIP node)
+    reconnect_delay:  5.0          # seconds between reconnect attempts

jetson/ros2_ws/src/saltybot_ntrip_client/package.xml

@@ -0,0 +1,32 @@
+<?xml version="1.0"?>
+<?xml-model href="http://download.ros.org/schema/package_format3.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
+<package format="3">
+  <name>saltybot_ntrip_client</name>
+  <version>0.1.0</version>
+  <description>
+    NTRIP client for RTK corrections.
+    Connects to an NTRIP caster (default: rtk2go.com:2101), receives RTCM3
+    correction data, and forwards it to the Here4 via DroneCAN
+    (uavcan.equipment.gnss.RTCMStream) on the CAN bus.
+    Reconnects automatically on disconnect.
+    Issue: https://gitea.vayrette.com/seb/saltylab-firmware/issues/725
+  </description>
+  <maintainer email="seb@vayrette.com">Sebastien Vayrette</maintainer>
+  <license>MIT</license>
+
+  <buildtool_depend>ament_python</buildtool_depend>
+
+  <depend>rclpy</depend>
+  <depend>std_msgs</depend>
+
+  <exec_depend>python3-pip</exec_depend>
+
+  <test_depend>ament_copyright</test_depend>
+  <test_depend>ament_flake8</test_depend>
+  <test_depend>ament_pep257</test_depend>
+  <test_depend>python3-pytest</test_depend>
+
+  <export>
+    <build_type>ament_python</build_type>
+  </export>
+</package>

jetson/ros2_ws/src/saltybot_ntrip_client/resource/saltybot_ntrip_client

@@ -0,0 +1 @@
+saltybot_ntrip_client

jetson/ros2_ws/src/saltybot_ntrip_client/saltybot_ntrip_client/ntrip_client_node.py

@@ -0,0 +1,207 @@
+#!/usr/bin/env python3
+"""
+ntrip_client_node.py — NTRIP client for Here4 RTK corrections
+Issue: https://gitea.vayrette.com/seb/saltylab-firmware/issues/725
+
+Connects to an NTRIP caster (default: rtk2go.com:2101), streams RTCM3
+correction data, and forwards it to the Here4 GPS via DroneCAN
+(uavcan.equipment.gnss.RTCMStream) on the CAN bus.
+
+Publishes:
+  /ntrip/status  std_msgs/String  — CONNECTED / DISCONNECTED / ERROR:<reason>
+
+Parameters:
+  ntrip_caster    (str)   rtk2go.com
+  ntrip_port      (int)   2101
+  ntrip_mount     (str)   ''       — required, e.g. 'RTCM3_GENERIC'
+  ntrip_user      (str)   ''       — leave empty for anonymous casters
+  ntrip_password  (str)   ''
+  can_interface   (str)   can0
+  can_bitrate     (int)   1000000
+  can_node_id     (int)   126      — DroneCAN local node ID for NTRIP node
+  reconnect_delay (float) 5.0     — seconds between reconnect attempts
+"""
+
+import base64
+import socket
+import threading
+import time
+
+import rclpy
+from rclpy.node import Node
+from std_msgs.msg import String
+
+try:
+    import dronecan
+except ImportError:
+    dronecan = None
+
+_NTRIP_AGENT  = 'saltybot-ntrip/1.0'
+_RTCM_CHUNK   = 512   # bytes per DroneCAN RTCMStream message (max 128 per frame)
+_RECV_BUF     = 4096
+
+
+class NtripClientNode(Node):
+    def __init__(self) -> None:
+        super().__init__('ntrip_client')
+
+        self.declare_parameter('ntrip_caster',    'rtk2go.com')
+        self.declare_parameter('ntrip_port',      2101)
+        self.declare_parameter('ntrip_mount',     '')
+        self.declare_parameter('ntrip_user',      '')
+        self.declare_parameter('ntrip_password',  '')
+        self.declare_parameter('can_interface',   'can0')
+        self.declare_parameter('can_bitrate',     1000000)
+        self.declare_parameter('can_node_id',     126)
+        self.declare_parameter('reconnect_delay', 5.0)
+
+        self._caster   = self.get_parameter('ntrip_caster').value
+        self._port     = self.get_parameter('ntrip_port').value
+        self._mount    = self.get_parameter('ntrip_mount').value
+        self._user     = self.get_parameter('ntrip_user').value
+        self._password = self.get_parameter('ntrip_password').value
+        self._iface    = self.get_parameter('can_interface').value
+        self._bitrate  = self.get_parameter('can_bitrate').value
+        self._node_id  = self.get_parameter('can_node_id').value
+        self._reconnect_delay = self.get_parameter('reconnect_delay').value
+
+        self._status_pub = self.create_publisher(String, '/ntrip/status', 10)
+
+        if dronecan is None:
+            self.get_logger().error(
+                'python-dronecan not installed. Run: pip install python-dronecan'
+            )
+            self._publish_status('ERROR:dronecan_not_installed')
+            return
+
+        if not self._mount:
+            self.get_logger().error(
+                'ntrip_mount parameter is required (e.g. RTCM3_GENERIC)'
+            )
+            self._publish_status('ERROR:no_mount_point')
+            return
+
+        self._dc_node = dronecan.make_node(
+            self._iface,
+            node_id=self._node_id,
+            bitrate=self._bitrate,
+        )
+
+        self._stop_event = threading.Event()
+        self._thread = threading.Thread(
+            target=self._ntrip_loop, daemon=True
+        )
+        self._thread.start()
+
+        self.get_logger().info(
+            f'NTRIP client started — '
+            f'{self._caster}:{self._port}/{self._mount}'
+        )
+
+    # ── NTRIP loop (reconnects on any error) ──────────────────────────────────
+
+    def _ntrip_loop(self) -> None:
+        while not self._stop_event.is_set() and rclpy.ok():
+            try:
+                self._connect_and_stream()
+            except Exception as exc:
+                self.get_logger().warn(f'NTRIP disconnected: {exc}')
+                self._publish_status(f'DISCONNECTED')
+            if not self._stop_event.is_set() and rclpy.ok():
+                self.get_logger().info(
+                    f'Reconnecting in {self._reconnect_delay}s…'
+                )
+                time.sleep(self._reconnect_delay)
+
+    def _connect_and_stream(self) -> None:
+        sock = socket.create_connection(
+            (self._caster, self._port), timeout=10.0
+        )
+        sock.settimeout(30.0)
+
+        # Send NTRIP HTTP/1.1 GET request
+        request = self._build_request()
+        sock.sendall(request.encode('ascii'))
+
+        # Read response header
+        header = b''
+        while b'\r\n\r\n' not in header:
+            chunk = sock.recv(256)
+            if not chunk:
+                raise ConnectionError('Connection closed during header read')
+            header += chunk
+
+        header_str = header.split(b'\r\n\r\n')[0].decode('ascii', errors='replace')
+        if 'ICY 200 OK' not in header_str and '200 OK' not in header_str:
+            raise ConnectionError(f'NTRIP rejected: {header_str[:120]}')
+
+        self.get_logger().info(
+            f'NTRIP connected to {self._caster}:{self._port}/{self._mount}'
+        )
+        self._publish_status('CONNECTED')
+
+        # Any trailing bytes after header are RTCM data
+        leftover = header.split(b'\r\n\r\n', 1)[1] if b'\r\n\r\n' in header else b''
+        if leftover:
+            self._forward_rtcm(leftover)
+
+        while not self._stop_event.is_set() and rclpy.ok():
+            data = sock.recv(_RECV_BUF)
+            if not data:
+                raise ConnectionError('NTRIP stream closed by server')
+            self._forward_rtcm(data)
+
+    def _build_request(self) -> str:
+        lines = [
+            f'GET /{self._mount} HTTP/1.1',
+            f'Host: {self._caster}:{self._port}',
+            f'User-Agent: {_NTRIP_AGENT}',
+            'Ntrip-Version: Ntrip/2.0',
+            'Connection: close',
+        ]
+        if self._user:
+            creds = base64.b64encode(
+                f'{self._user}:{self._password}'.encode()
+            ).decode()
+            lines.append(f'Authorization: Basic {creds}')
+        lines += ['', '']
+        return '\r\n'.join(lines)
+
+    # ── DroneCAN RTCMStream forwarding ────────────────────────────────────────
+
+    def _forward_rtcm(self, data: bytes) -> None:
+        """Chunk RTCM data into DroneCAN RTCMStream messages."""
+        for i in range(0, len(data), _RTCM_CHUNK):
+            chunk = data[i:i + _RTCM_CHUNK]
+            try:
+                msg = dronecan.uavcan.equipment.gnss.RTCMStream()
+                msg.data = list(chunk)
+                self._dc_node.broadcast(msg)
+                self._dc_node.spin(timeout=0.0)
+            except Exception as exc:
+                self.get_logger().warn(f'DroneCAN send error: {exc}')
+
+    def _publish_status(self, status: str) -> None:
+        msg = String()
+        msg.data = status
+        self._status_pub.publish(msg)
+
+    def destroy_node(self) -> None:
+        self._stop_event.set()
+        super().destroy_node()
+
+
+def main(args=None) -> None:
+    rclpy.init(args=args)
+    node = NtripClientNode()
+    try:
+        rclpy.spin(node)
+    except KeyboardInterrupt:
+        pass
+    finally:
+        node.destroy_node()
+        rclpy.shutdown()
+
+
+if __name__ == '__main__':
+    main()

jetson/ros2_ws/src/saltybot_ntrip_client/setup.cfg

@@ -0,0 +1,4 @@
+[develop]
+script_dir=$base/lib/saltybot_ntrip_client
+[install]
+install_scripts=$base/lib/saltybot_ntrip_client

jetson/ros2_ws/src/saltybot_ntrip_client/setup.py

@@ -0,0 +1,32 @@
+from setuptools import find_packages, setup
+import os
+from glob import glob
+
+package_name = 'saltybot_ntrip_client'
+
+setup(
+    name=package_name,
+    version='0.1.0',
+    packages=find_packages(exclude=['test']),
+    data_files=[
+        ('share/ament_index/resource_index/packages',
+            ['resource/' + package_name]),
+        ('share/' + package_name, ['package.xml']),
+        (os.path.join('share', package_name, 'launch'),
+            glob('launch/*.py')),
+        (os.path.join('share', package_name, 'config'),
+            glob('config/*.yaml')),
+    ],
+    install_requires=['setuptools'],
+    zip_safe=True,
+    maintainer='Sebastien Vayrette',
+    maintainer_email='seb@vayrette.com',
+    description='NTRIP client — RTCM3 corrections via DroneCAN to Here4',
+    license='MIT',
+    tests_require=['pytest'],
+    entry_points={
+        'console_scripts': [
+            'ntrip_client_node = saltybot_ntrip_client.ntrip_client_node:main',
+        ],
+    },
+)

jetson/ros2_ws/src/saltybot_outdoor/config/outdoor_nav_params.yaml

@@ -1,22 +1,29 @@
 # outdoor_nav_params.yaml — Outdoor navigation configuration for SaltyBot
 #
 # Hardware: Jetson Orin Nano Super / SIM7600X cellular GPS (±2.5 m CEP)
-# RTK upgrade: u-blox ZED-F9P → ±2 cm CEP (set use_rtk: true when installed)
+# RTK (active): CubePilot Here4 → ±2 cm CEP via DroneCAN (Issue #725)
+#   - Connected via CANable 2.0 (SocketCAN can0) at 1 Mbps
+#   - RTK corrections from NTRIP caster via saltybot_ntrip_client
+#   - Launch: docker compose up -d here4-gps
+#             (set NTRIP_MOUNT / NTRIP_USER / NTRIP_PASSWORD env vars)
 #
 # ── GPS quality notes ────────────────────────────────────────────────────────
 # SIM7600X reports STATUS_FIX (0) in open sky, STATUS_NO_FIX (-1) indoors.
-# RTK ZED-F9P reports STATUS_GBAS_FIX (2) when corrections received.
+# Here4 DroneCAN fix_type mapping (saltybot_dronecan_gps):
+#   5 = RTK_FLOAT → STATUS_GBAS_FIX (2) — sub-metre
+#   6 = RTK_FIXED → STATUS_GBAS_FIX (2) — ±2 cm (best)
+# Monitor: ros2 topic echo /gps/rtk_status
 # Goal tolerance automatically tightens from 2.0m (cellular) to 0.3m (RTK).
 #
-# ── RTK upgrade procedure ────────────────────────────────────────────────────
+# ── Here4 setup procedure ───────────────────────────────────────────────────
-# 1. Connect ZED-F9P to /dev/ttyTHS0 (Orin 40-pin UART, pins 8/10)
+# 1. can_setup.sh up dronecan         # bring up can0 at 1Mbps
-# 2. Set NTRIP credentials in rtk_gps.launch.py
+# 2. Set NTRIP_MOUNT, NTRIP_USER, NTRIP_PASSWORD in .env
-# 3. Run: ros2 launch saltybot_outdoor rtk_gps.launch.py
+# 3. docker compose up -d here4-gps
-# 4. Verify: ros2 topic echo /gps/fix | grep status
+# 4. Verify: ros2 topic echo /gps/rtk_status  → RTK_FIXED
-#    → status.status == 2 (STATUS_GBAS_FIX) = RTK fixed
+# 5. saltybot-outdoor: set use_rtk:=true in docker-compose.yml
 #
 # References:
-#   SparkFun RTK Express: https://docs.sparkfun.com/SparkFun_RTK_Everywhere_Firmware/
+#   Here4 manual: https://docs.cubepilot.org/user-guides/here-4/here-4-manual
 #   NTRIP caster list: https://rtk2go.com/sample-map/
 # ─────────────────────────────────────────────────────────────────────────────
 
@@ -96,3 +103,26 @@ global_costmap:
         inflation_radius: 0.50
       obstacle_layer:
         observation_sources: scan surround_cameras
+
+# ── Here4 RTK GPS configuration (Issue #725) ────────────────────────────────
+# Active when here4-gps docker service is running.
+# The dronecan_gps node publishes on the same /gps/fix topic as SIM7600X,
+# so gps_waypoint_follower picks up RTK automatically.
+# Set use_rtk:=true in saltybot-outdoor docker command to tighten tolerances.
+here4_gps:
+  ros__parameters:
+    # CAN bus — must match can_setup.sh dronecan mode and docker-compose device
+    can_interface:    "can0"
+    can_bitrate:      1000000   # 1 Mbps — Here4 DroneCAN default
+    # DroneCAN node IDs (must be unique on bus; VESCs use 61 and 79)
+    gps_node_id:      127
+    ntrip_node_id:    126
+    # NTRIP — override via env vars NTRIP_MOUNT / NTRIP_USER / NTRIP_PASSWORD
+    ntrip_caster:     "rtk2go.com"
+    ntrip_port:       2101
+    ntrip_mount:      ""        # set your mount point
+    ntrip_user:       ""        # rtk2go.com requires a valid email address
+    ntrip_password:   ""
+    reconnect_delay:  5.0       # seconds between NTRIP reconnect attempts
+    # RTK goal tolerance — applied by gps_waypoint_follower when use_rtk:=true
+    goal_tolerance_xy_rtk: 0.3  # metres (vs 2.0m cellular)

jetson/scripts/can_setup.sh

@@ -1,22 +1,36 @@
 #!/usr/bin/env bash
-# can_setup.sh — Bring up CANable 2.0 (gs_usb) as can0 at 500 kbps
+# can_setup.sh — Bring up CANable 2.0 (gs_usb) as can0
 # Issue: https://gitea.vayrette.com/seb/saltylab-firmware/issues/643
 #
 # Usage:
-#   sudo ./can_setup.sh          # bring up
+#   sudo ./can_setup.sh               # bring up (default: 500kbps for VESC)
-#   sudo ./can_setup.sh down     # bring down
+#   sudo ./can_setup.sh up dronecan   # bring up at 1Mbps for Here4 DroneCAN
-#   sudo ./can_setup.sh verify   # candump one-shot check (Ctrl-C to stop)
+#   sudo ./can_setup.sh down
+#   sudo ./can_setup.sh verify        # candump one-shot check (Ctrl-C to stop)
 #
-# VESCs on bus: CAN ID 61 (0x3D) and CAN ID 79 (0x4F), 500 kbps
+# Bitrate modes:
+#   default / vesc     — 500 kbps  (VESC IDs 0x3D/0x4F)
+#   dronecan / here4   — 1000 kbps (CubePilot Here4 RTK GPS, DroneCAN default)
+#
+# CAN_BITRATE env var overrides both modes.
 set -euo pipefail
 
 IFACE="${CAN_IFACE:-can0}"
-BITRATE="${CAN_BITRATE:-500000}"
 
 log() { echo "[can_setup] $*"; }
 die() { echo "[can_setup] ERROR: $*" >&2; exit 1; }
 
 cmd="${1:-up}"
+mode="${2:-vesc}"
+
+# Resolve bitrate: env var wins, then mode keyword, then 500k default
+if [[ -n "${CAN_BITRATE:-}" ]]; then
+    BITRATE="$CAN_BITRATE"
+elif [[ "$mode" == "dronecan" || "$mode" == "here4" ]]; then
+    BITRATE=1000000
+else
+    BITRATE=500000
+fi
 
 case "$cmd" in
   up)
@@ -25,7 +39,7 @@ case "$cmd" in
         die "$IFACE not found — is CANable 2.0 plugged in and gs_usb loaded?"
     fi
 
-    log "Bringing up $IFACE at ${BITRATE} bps..."
+    log "Bringing up $IFACE at ${BITRATE} bps (mode: ${mode})..."
     ip link set "$IFACE" down 2>/dev/null || true
     ip link set "$IFACE" up type can bitrate "$BITRATE"
     ip link set "$IFACE" up
@@ -40,13 +54,17 @@ case "$cmd" in
     ;;
 
   verify)
-    log "Listening on $IFACE — expecting frames from VESC IDs 0x3D (61) and 0x4F (79)"
+    if [[ "$mode" == "dronecan" || "$mode" == "here4" ]]; then
+        log "Listening on $IFACE — expecting DroneCAN frames from Here4 GPS (1Mbps)"
+    else
+        log "Listening on $IFACE — expecting frames from VESC IDs 0x3D (61) and 0x4F (79)"
+    fi
     log "Press Ctrl-C to stop."
     exec candump "$IFACE"
     ;;
 
   *)
-    echo "Usage: $0 [up|down|verify]"
+    echo "Usage: $0 [up [vesc|dronecan]|down|verify [dronecan]]"
     exit 1
     ;;
 esac