Architecture Temps Réel (ROS 2 & DDS)

rclcpp::executors::StaticSingleThreadedExecutor exec; auto node_ctrl = std::make_shared<ControllerNode>(); rclcpp::CallbackGroup::SharedPtr cb_ctrl = node_ctrl->create_callback_group(rclcpp::CallbackGroupType::MutuallyExclusive); exec.add_node(node_ctrl); exec.spin();

# Composable nodes (composition) ros2 run rclcpp_components component_container_mt ros2 component load /ComponentManager pkg DetectNode --node-name detect

# qos_overrides.yaml /imu/data: reliability: reliable history: keep_last depth: 10 deadline: 2ms /camera/image_raw: reliability: best_effort history: keep_last depth: 5 /ctrl/cmd_out: reliability: reliable liveliness: manual_by_topic deadline: 5ms

# Affinité IRQ cam & réseau echo 4 > /proc/irq/xx/smp_affinity_list # Gouverneur CPU cpupower frequency-set -g performance

# Pas d’allocation pendant le vol mlockall(MCL_CURRENT | MCL_FUTURE); rclcpp::memory_strategy::preallocate();

<!-- Fast-DDS --> <transport_descriptors> <transport_descriptor>... <sendBufferSize>4M</sendBufferSize> <TTL>1</TTL> ...</transport_descriptor> </transport_descriptors>

# PTP (time sync) – chrony/ptp4l ptp4l -i eth0 -m phc2sys -s CLOCK_REALTIME -c /dev/ptp0 -O 0

# Tracer un nœud (LTTng) ros2 run tracetools_trace trace -s flight_session # Visualiser dans Perfetto traceconv proto flight_session > trace.pb

# rosbag2 – QoS override + compression ros2 bag record /camera/image_raw /imu/data \ --qos-profile-overrides-path qos_overrides.yaml \ --compression-format zstd --compression-mode file

# Générer clés & politiques ros2 security create_keystore keystore ros2 security create_key --keystore keystore /drone/ctrl # Lancer avec sécurité ROS_SECURITY_ENABLE=true ROS_SECURITY_STRATEGY=Enforce \ ROS_SECURITY_KEYSTORE=keystore ros2 run pkg node

<!-- permissions.xml (extrait) --> <permissions><grant><subject_name>drone/ctrl</subject_name> <allow_rule><publish><topics><topic>/ctrl/cmd_out</topic></topics></publish></allow_rule> </grant></permissions>

# Agent micro-ROS ros2 run micro_ros_agent micro_ros_agent udp4 --port 8888 # Client MCU (pseudo) rclc_publisher_init_default(&pub, node, type_support, "/imu/raw");