AP_DDS: RC channels message

Tools/ros2/ardupilot_dds_tests/test/ardupilot_dds_tests/test_rc_msg_received.py

@@ -0,0 +1,156 @@
+# Copyright 2023 ArduPilot.org.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+"""
+Bring up ArduPilot SITL and check the RC message is being published.
+
+Checks whether a message is received and that only frame_id = '0' is received, 
+as SITL has only one rc available.
+
+colcon test --packages-select ardupilot_dds_tests \
+--event-handlers=console_cohesion+ --pytest-args -k test_rc_msg_received
+
+"""
+
+import launch_pytest
+import pytest
+import rclpy
+import rclpy.node
+import threading
+
+from launch import LaunchDescription
+
+from launch_pytest.tools import process as process_tools
+
+from rclpy.qos import QoSProfile
+from rclpy.qos import QoSReliabilityPolicy
+from rclpy.qos import QoSHistoryPolicy
+
+from ardupilot_msgs.msg import Rc
+
+TOPIC = "ap/rc"
+
+
+class RcListener(rclpy.node.Node):
+    """Subscribe to Rc messages."""
+
+    def __init__(self):
+        """Initialise the node."""
+        super().__init__("rc_listener")
+        self.msg_event_object = threading.Event()
+
+        # Declare and acquire `topic` parameter
+        self.declare_parameter("topic", TOPIC)
+        self.topic = self.get_parameter("topic").get_parameter_value().string_value
+
+    def start_subscriber(self):
+        """Start the subscriber."""
+        qos_profile = QoSProfile(
+            reliability=QoSReliabilityPolicy.BEST_EFFORT,
+            history=QoSHistoryPolicy.KEEP_LAST,
+            depth=1,
+        )
+
+        self.subscription = self.create_subscription(Rc, self.topic, self.subscriber_callback, qos_profile)
+
+        # Add a spin thread.
+        self.ros_spin_thread = threading.Thread(target=lambda node: rclpy.spin(node), args=(self,))
+        self.ros_spin_thread.start()
+
+    def subscriber_callback(self, msg):
+        """Process a Rc message."""
+        self.msg_event_object.set()
+
+
+@launch_pytest.fixture
+def launch_sitl_copter_dds_serial(sitl_copter_dds_serial):
+    """Fixture to create the launch description."""
+    sitl_ld, sitl_actions = sitl_copter_dds_serial
+
+    ld = LaunchDescription(
+        [
+            sitl_ld,
+            launch_pytest.actions.ReadyToTest(),
+        ]
+    )
+    actions = sitl_actions
+    yield ld, actions
+
+
+@launch_pytest.fixture
+def launch_sitl_copter_dds_udp(sitl_copter_dds_udp):
+    """Fixture to create the launch description."""
+    sitl_ld, sitl_actions = sitl_copter_dds_udp
+
+    ld = LaunchDescription(
+        [
+            sitl_ld,
+            launch_pytest.actions.ReadyToTest(),
+        ]
+    )
+    actions = sitl_actions
+    yield ld, actions
+
+
+@pytest.mark.launch(fixture=launch_sitl_copter_dds_serial)
+def test_dds_serial_rc_msg_recv(launch_context, launch_sitl_copter_dds_serial):
+    """Test rc messages are published by AP_DDS."""
+    _, actions = launch_sitl_copter_dds_serial
+    virtual_ports = actions["virtual_ports"].action
+    micro_ros_agent = actions["micro_ros_agent"].action
+    mavproxy = actions["mavproxy"].action
+    sitl = actions["sitl"].action
+
+    # Wait for process to start.
+    process_tools.wait_for_start_sync(launch_context, virtual_ports, timeout=2)
+    process_tools.wait_for_start_sync(launch_context, micro_ros_agent, timeout=2)
+    process_tools.wait_for_start_sync(launch_context, mavproxy, timeout=2)
+    process_tools.wait_for_start_sync(launch_context, sitl, timeout=2)
+
+    rclpy.init()
+    try:
+        node = RcListener()
+        node.start_subscriber()
+        msgs_received_flag = node.msg_event_object.wait(timeout=10.0)
+        assert msgs_received_flag, f"Did not receive '{TOPIC}' msgs."
+    finally:
+        rclpy.shutdown()
+    yield
+
+
+@pytest.mark.launch(fixture=launch_sitl_copter_dds_udp)
+def test_dds_udp_rc_msg_recv(launch_context, launch_sitl_copter_dds_udp):
+    """Test rc messages are published by AP_DDS."""
+    _, actions = launch_sitl_copter_dds_udp
+    micro_ros_agent = actions["micro_ros_agent"].action
+    mavproxy = actions["mavproxy"].action
+    sitl = actions["sitl"].action
+
+    # Wait for process to start.
+    process_tools.wait_for_start_sync(launch_context, micro_ros_agent, timeout=2)
+    process_tools.wait_for_start_sync(launch_context, mavproxy, timeout=2)
+    process_tools.wait_for_start_sync(launch_context, sitl, timeout=2)
+
+    rclpy.init()
+    try:
+        node = RcListener()
+        node.start_subscriber()
+        msgs_received_flag = node.msg_event_object.wait(timeout=10.0)
+        assert msgs_received_flag, f"Did not receive '{TOPIC}' msgs."
+
+    finally:
+        rclpy.shutdown()
+    yield
+

Tools/ros2/ardupilot_msgs/CMakeLists.txt

@@ -14,6 +14,7 @@ find_package(rosidl_default_generators REQUIRED)
 
 rosidl_generate_interfaces(${PROJECT_NAME}
   "msg/GlobalPosition.msg"
+  "msg/Rc.msg"
   "msg/Status.msg"
   "srv/ArmMotors.srv"
   "srv/ModeSwitch.srv"

Tools/ros2/ardupilot_msgs/msg/Rc.msg

@@ -0,0 +1,13 @@
+std_msgs/Header header
+
+# returns true if radio is connected.
+bool is_connected
+
+# returns [0, 100] for receiver RSSI.
+uint8 receiver_rssi
+
+# channels values.
+int16[<=32] channels
+
+# sets true if a channel is overridden.
+bool[<=32] active_overrides

libraries/AP_DDS/AP_DDS_Client.cpp

@@ -32,6 +32,9 @@
 #if AP_DDS_VTOL_TAKEOFF_SERVER_ENABLED
 #include "ardupilot_msgs/srv/Takeoff.h"
 #endif // AP_DDS_VTOL_TAKEOFF_SERVER_ENABLED
+#if AP_DDS_RC_PUB_ENABLED
+#include "AP_RSSI/AP_RSSI.h"
+#endif // AP_DDS_RC_PUB_ENABLED
 
 #if AP_EXTERNAL_CONTROL_ENABLED
 #include "AP_DDS_ExternalControl.h"
@@ -65,6 +68,9 @@ static constexpr uint16_t DELAY_LOCAL_VELOCITY_TOPIC_MS = AP_DDS_DELAY_LOCAL_VEL
 #if AP_DDS_AIRSPEED_PUB_ENABLED
 static constexpr uint16_t DELAY_AIRSPEED_TOPIC_MS = AP_DDS_DELAY_AIRSPEED_TOPIC_MS;
 #endif // AP_DDS_AIRSPEED_PUB_ENABLED
+#if AP_DDS_RC_PUB_ENABLED
+static constexpr uint16_t DELAY_RC_TOPIC_MS = AP_DDS_DELAY_RC_TOPIC_MS;
+#endif // AP_DDS_RC_PUB_ENABLED
 #if AP_DDS_GEOPOSE_PUB_ENABLED
 static constexpr uint16_t DELAY_GEO_POSE_TOPIC_MS = AP_DDS_DELAY_GEO_POSE_TOPIC_MS;
 #endif // AP_DDS_GEOPOSE_PUB_ENABLED
@@ -522,6 +528,38 @@ bool AP_DDS_Client::update_topic(geometry_msgs_msg_Vector3Stamped& msg)
 }
 #endif // AP_DDS_AIRSPEED_PUB_ENABLED
 
+#if AP_DDS_RC_PUB_ENABLED
+bool AP_DDS_Client::update_topic(ardupilot_msgs_msg_Rc& msg)
+{
+    update_topic(msg.header.stamp);
+    AP_RSSI *ap_rssi = AP_RSSI::get_singleton();
+    auto rc = RC_Channels::get_singleton();
+    static int16_t counter = 0;
+
+    // Is connected if not in failsafe.
+    // This is only valid if the RC has been connected at least once
+    msg.is_connected = !rc->in_rc_failsafe();
+    // Receiver RSSI is reported between 0.0 and 1.0.
+    msg.receiver_rssi = static_cast<int16_t>(ap_rssi->read_receiver_rssi()*100.f);
+
+    // Limit the max number of available channels to 8
+    msg.channels_size = MIN(static_cast<uint32_t>(rc->get_valid_channel_count()), 32U);
+    msg.active_overrides_size = msg.channels_size;
+    if (msg.channels_size) {
+        for (uint8_t i = 0; i < static_cast<uint8_t>(msg.channels_size); i++) {
+            msg.channels[i] = rc->rc_channel(i)->get_radio_in();
+            msg.active_overrides[i] = rc->rc_channel(i)->has_override();
+        }
+    } else {
+        // If no channels are available, the RC is disconnected.
+        msg.is_connected = false;
+    }
+
+    // Return true if Radio is connected, or once every 10 steps to reduce useless traffic.
+    return msg.is_connected ? true : (counter++ % 10 == 0);
+}
+#endif // AP_DDS_RC_PUB_ENABLED
+
 #if AP_DDS_GEOPOSE_PUB_ENABLED
 void AP_DDS_Client::update_topic(geographic_msgs_msg_GeoPoseStamped& msg)
 {
@@ -1557,6 +1595,22 @@ void AP_DDS_Client::write_tx_local_airspeed_topic()
     }
 }
 #endif // AP_DDS_AIRSPEED_PUB_ENABLED
+#if AP_DDS_RC_PUB_ENABLED
+void AP_DDS_Client::write_tx_local_rc_topic()
+{
+    WITH_SEMAPHORE(csem);
+    if (connected) {
+        ucdrBuffer ub {};
+        const uint32_t topic_size = ardupilot_msgs_msg_Rc_size_of_topic(&tx_local_rc_topic, 0);
+        uxr_prepare_output_stream(&session, reliable_out, topics[to_underlying(TopicIndex::LOCAL_RC_PUB)].dw_id, &ub, topic_size);
+        const bool success = ardupilot_msgs_msg_Rc_serialize_topic(&ub, &tx_local_rc_topic);
+        if (!success) {
+            // TODO sometimes serialization fails on bootup. Determine why.
+            // AP_HAL::panic("FATAL: DDS_Client failed to serialize\n");
+        }
+    }
+}
+#endif // AP_DDS_RC_PUB_ENABLED
 #if AP_DDS_IMU_PUB_ENABLED
 void AP_DDS_Client::write_imu_topic()
 {
@@ -1708,6 +1762,14 @@ void AP_DDS_Client::update()
         }
     }
 #endif // AP_DDS_AIRSPEED_PUB_ENABLED
+#if AP_DDS_RC_PUB_ENABLED
+    if (cur_time_ms - last_rc_time_ms > DELAY_RC_TOPIC_MS) {
+        last_rc_time_ms = cur_time_ms;
+        if (update_topic(tx_local_rc_topic)) {
+            write_tx_local_rc_topic();
+        }
+    }
+#endif // AP_DDS_RC_PUB_ENABLED
 #if AP_DDS_IMU_PUB_ENABLED
     if (cur_time_ms - last_imu_time_ms > DELAY_IMU_TOPIC_MS) {
         update_topic(imu_topic);

libraries/AP_DDS/AP_DDS_Client.h

@@ -43,6 +43,9 @@
 #if AP_DDS_AIRSPEED_PUB_ENABLED
 #include "geometry_msgs/msg/Vector3Stamped.h"
 #endif // AP_DDS_AIRSPEED_PUB_ENABLED
+#if AP_DDS_RC_PUB_ENABLED
+#include "ardupilot_msgs/msg/Rc.h"
+#endif // AP_DDS_RC_PUB_ENABLED
 #if AP_DDS_GEOPOSE_PUB_ENABLED
 #include "geographic_msgs/msg/GeoPoseStamped.h"
 #endif // AP_DDS_GEOPOSE_PUB_ENABLED
@@ -160,6 +163,15 @@ class AP_DDS_Client
     static bool update_topic(geometry_msgs_msg_Vector3Stamped& msg);
 #endif //AP_DDS_AIRSPEED_PUB_ENABLED
 
+#if AP_DDS_RC_PUB_ENABLED
+    ardupilot_msgs_msg_Rc tx_local_rc_topic;
+    // The last ms timestamp AP_DDS wrote a rc message
+    uint64_t last_rc_time_ms;
+    //! @brief Serialize the current local rc and publish to the IO stream(s)
+    void write_tx_local_rc_topic();
+    static bool update_topic(ardupilot_msgs_msg_Rc& msg);
+#endif //AP_DDS_RC_PUB_ENABLED
+
 #if AP_DDS_BATTERY_STATE_PUB_ENABLED
     sensor_msgs_msg_BatteryState battery_state_topic;
     // The last ms timestamp AP_DDS wrote a BatteryState message

libraries/AP_DDS/AP_DDS_Topic_Table.h

@@ -39,6 +39,9 @@ enum class TopicIndex: uint8_t {
 #if AP_DDS_AIRSPEED_PUB_ENABLED
     LOCAL_AIRSPEED_PUB,
 #endif // AP_DDS_AIRSPEED_PUB_ENABLED
+#if AP_DDS_RC_PUB_ENABLED
+    LOCAL_RC_PUB,
+#endif // AP_DDS_RC_PUB_ENABLED
 #if AP_DDS_GEOPOSE_PUB_ENABLED
     GEOPOSE_PUB,
 #endif // AP_DDS_GEOPOSE_PUB_ENABLED
@@ -220,6 +223,24 @@ constexpr struct AP_DDS_Client::Topic_table AP_DDS_Client::topics[] = {
         },
     },
 #endif // AP_DDS_AIRSPEED_PUB_ENABLED
+#if AP_DDS_RC_PUB_ENABLED
+    {
+        .topic_id = to_underlying(TopicIndex::LOCAL_RC_PUB),
+        .pub_id = to_underlying(TopicIndex::LOCAL_RC_PUB),
+        .sub_id = to_underlying(TopicIndex::LOCAL_RC_PUB),
+        .dw_id = uxrObjectId{.id=to_underlying(TopicIndex::LOCAL_RC_PUB), .type=UXR_DATAWRITER_ID},
+        .dr_id = uxrObjectId{.id=to_underlying(TopicIndex::LOCAL_RC_PUB), .type=UXR_DATAREADER_ID},
+        .topic_rw = Topic_rw::DataWriter,
+        .topic_name = "rt/ap/rc",
+        .type_name = "ardupilot_msgs::msg::dds_::Rc_",
+        .qos = {
+            .durability = UXR_DURABILITY_VOLATILE,
+            .reliability = UXR_RELIABILITY_BEST_EFFORT,
+            .history = UXR_HISTORY_KEEP_LAST,
+            .depth = 1,
+        },
+    },
+#endif // AP_DDS_RC_PUB_ENABLED
 #if AP_DDS_GEOPOSE_PUB_ENABLED
     {
         .topic_id = to_underlying(TopicIndex::GEOPOSE_PUB),

libraries/AP_DDS/AP_DDS_config.h

@@ -86,6 +86,14 @@
 #define AP_DDS_DELAY_AIRSPEED_TOPIC_MS 33
 #endif
 
+#ifndef AP_DDS_RC_PUB_ENABLED
+#define AP_DDS_RC_PUB_ENABLED 1
+#endif
+
+#ifndef AP_DDS_DELAY_RC_TOPIC_MS
+#define AP_DDS_DELAY_RC_TOPIC_MS 100
+#endif
+
 #ifndef AP_DDS_BATTERY_STATE_PUB_ENABLED
 #define AP_DDS_BATTERY_STATE_PUB_ENABLED 1
 #endif

libraries/AP_DDS/Idl/ardupilot_msgs/msg/Rc.idl

@@ -0,0 +1,29 @@
+// generated from rosidl_adapter/resource/msg.idl.em
+// with input from ardupilot_msgs/msg/Rc.msg
+// generated code does not contain a copyright notice
+
+#include "std_msgs/msg/Header.idl"
+
+module ardupilot_msgs {
+  module msg {
+    struct Rc {
+      std_msgs::msg::Header header;
+
+      @verbatim (language="comment", text=
+        "returns true if radio is connected.")
+      boolean is_connected;
+
+      @verbatim (language="comment", text=
+        "returns [0, 100] for receiver RSSI.")
+      uint8 receiver_rssi;
+
+      @verbatim (language="comment", text=
+        "channels values.")
+      sequence<int16, 32> channels;
+
+      @verbatim (language="comment", text=
+        "sets true if a channel is overridden.")
+      sequence<boolean, 32> active_overrides;
+    };
+  };
+};

libraries/AP_DDS/README.md

@@ -180,6 +180,8 @@ Published topics:
  * /ap/imu/experimental/data [sensor_msgs/msg/Imu] 1 publisher
  * /ap/navsat [sensor_msgs/msg/NavSatFix] 1 publisher
  * /ap/pose/filtered [geometry_msgs/msg/PoseStamped] 1 publisher
+ * /ap/rc [ardupilot_msgs/msg/Rc] 1 publisher
+ * /ap/status [ardupilot_msgs/msg/Status] 1 publisher
  * /ap/tf_static [tf2_msgs/msg/TFMessage] 1 publisher
  * /ap/time [builtin_interfaces/msg/Time] 1 publisher
  * /ap/twist/filtered [geometry_msgs/msg/TwistStamped] 1 publisher