Create initial EFC SITL (Software In The Loop) application

.github/workflows/build.yml

@@ -34,3 +34,31 @@ jobs:
         run: |
           cd ./efc
           west build -b eurus_nexus_v1_1 app
+
+  build-sitl:
+    runs-on: ubuntu-24.04
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          submodules: recursive
+          path: efc
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: 3.12
+
+      - name: Install project requirements
+        run: |
+          sudo apt-get update && sudo apt-get update
+          sudo apt-get install libuv1-dev
+          cd ./efc
+          python -m venv python_venv
+          ./python_venv/bin/pip install -r requirements.txt
+
+      - name: Build project
+        run: |
+          cd ./efc
+          cmake -B build -S sitl
+          cmake --build build

README.md

@@ -41,6 +41,38 @@ cd efc
 west build -b eurus_nexus_v1_1 app
 ```
 
+## EFC SITL
+SITL (Software In The Loop) for the EFC autopilot runs the EFC flight control software on a host machine (PC) while interfacing with a flight simulator that models vehicle dynamics and the environment. The simulator provides synthetic sensor data to EFC, and EFC computes and returns actuator commands, forming a closed control loop. This setup enables realistic testing and validation of the EFC autopilot without physical hardware.  
+EFC SITL is designed for the EFC autopilot to interact with [jMAVSim](https://github.com/PX4/jMAVSim) simulator.
+
+## Build EFC SITL
+
+### EFC SITL build dependencies
+
+EFC SITL depends on [libuv](https://libuv.org/); therefore, `libuv` must be installed on the host system.  
+On Debian-based systems, `libuv` can be installed using:
+```bash
+apt-get install libuv1-dev
+```
+
+### EFC SITL build procedure
+
+1. Create a efc-specific virtual environment and install the required packages (if it hasn't already been created):
+```bash
+cd ~/eurus/efc
+python -m venv python_venv
+source python_venv/bin/activate
+pip install -r requirements.txt
+deactivate
+```
+> Note: Sourcing the efc virtual environment will not be necessary after the first time as CMake will use the virtual environment python binary.
+
+2. Use CMake to build EFC SITL
+```bash
+cd ~/eurus/efc
+cmake -B build -S sitl
+cmake --build build 
+```
 
 ## Contributing
 The `efc` project uses code formatting rules described in `.clang-format`.

sitl/CMakeLists.txt

@@ -0,0 +1,32 @@
+# This file is part of the efc project <https://github.com/eurus-project/efc/>.
+# Copyright (c) (2024 - Present), The efc developers.
+#
+# 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, version 3.
+#
+# 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 <http://www.gnu.org/licenses/>.
+
+cmake_minimum_required(VERSION 3.20.0)
+
+project(efc-sitl
+    VERSION 0.1
+    LANGUAGES C
+)
+
+set(EFC_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/..)
+if(CMAKE_HOST_WIN32)
+	set(VENV_PYTHON ${EFC_SOURCE_DIR}/python_venv/Scripts/python)
+else()
+	set(VENV_PYTHON ${EFC_SOURCE_DIR}/python_venv/bin/python)
+endif()
+
+add_subdirectory(external/mavlink)
+add_subdirectory(external/autopilot)
+add_subdirectory(app)

sitl/app/CMakeLists.txt

@@ -0,0 +1,35 @@
+# This file is part of the efc project <https://github.com/eurus-project/efc/>.
+# Copyright (c) (2024 - Present), The efc developers.
+#
+# 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, version 3.
+#
+# 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 <http://www.gnu.org/licenses/>.
+
+cmake_minimum_required(VERSION 3.20.0)
+
+add_executable(efc_sitl
+    src/main.c
+)
+
+target_link_libraries(efc_sitl
+PUBLIC
+    mavlink
+    uv
+)
+
+target_compile_options(efc_sitl
+PUBLIC
+    -Wall
+    -Wextra
+    -Werror
+
+    -Wno-unused-parameter
+)

sitl/app/src/main.c

@@ -0,0 +1,79 @@
+/*
+ * This file is part of the efc project <https://github.com/eurus-project/efc/>.
+ * Copyright (c) (2024 - Present), The efc developers.
+ *
+ * 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, version 3.
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include <uv.h>
+
+// MAVLink headers
+// clang-format off
+#include "mavlink_custom.h" // Needs to be included before any MAVLink header inclusion
+#include "common/mavlink.h"
+// clang-format on
+
+#define TARGET_IP "127.0.0.1"
+#define TARGET_PORT 14560
+
+static uv_udp_t udp;
+static uv_udp_send_t send_req;
+static struct sockaddr_in target_addr;
+
+const uint8_t telemetry_system_id = 0;
+const uint8_t telemetry_component_id = MAV_COMP_ID_AUTOPILOT1;
+const uint8_t telemetry_channel_ground = MAVLINK_COMM_0;
+
+static mavlink_message_t mavlink_msg;
+static uint8_t mavlink_ser_buf[MAVLINK_MAX_PACKET_LEN];
+
+static void udp_cb(uv_udp_send_t *req, int status) {
+    if (status < 0) {
+        fprintf(stderr, "UDP send error: %s\n", uv_strerror(status));
+    }
+}
+
+static void heartbeat_timer_cb(uv_timer_t *handle) {
+    mavlink_msg_heartbeat_pack_chan(
+        telemetry_system_id, telemetry_component_id, telemetry_channel_ground,
+        &mavlink_msg, MAV_TYPE_GENERIC, MAV_AUTOPILOT_GENERIC,
+        MAV_MODE_FLAG_MANUAL_INPUT_ENABLED, 0, MAV_STATE_ACTIVE);
+
+    const uint16_t telemetry_msg_len =
+        mavlink_msg_to_send_buffer(mavlink_ser_buf, &mavlink_msg);
+
+    uv_buf_t buf = uv_buf_init((char *)mavlink_ser_buf, telemetry_msg_len);
+
+    uv_udp_send(&send_req, &udp, &buf, 1, (const struct sockaddr *)&target_addr,
+                udp_cb);
+}
+
+int main(void) {
+    uv_loop_t *loop = uv_default_loop();
+
+    uv_udp_init(loop, &udp);
+    uv_ip4_addr(TARGET_IP, TARGET_PORT, &target_addr);
+
+    uv_timer_t heartbeat_timer;
+    uv_timer_init(loop, &heartbeat_timer);
+    uv_timer_start(&heartbeat_timer, heartbeat_timer_cb, 0, 1000);
+
+    uv_run(loop, UV_RUN_DEFAULT);
+
+    uv_loop_close(loop);
+
+    return 0;
+}

sitl/external/autopilot/CMakeLists.txt

@@ -0,0 +1,16 @@
+# This file is part of the efc project <https://github.com/eurus-project/efc/>.
+# Copyright (c) (2024 - Present), The efc developers.
+#
+# 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, version 3.
+#
+# 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 <http://www.gnu.org/licenses/>.
+
+cmake_minimum_required(VERSION 3.20.0)

sitl/external/mavlink/CMakeLists.txt

@@ -0,0 +1,67 @@
+# This file is part of the efc project <https://github.com/eurus-project/efc/>.
+# Copyright (c) (2024 - Present), The efc developers.
+#
+# 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, version 3.
+#
+# 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 <http://www.gnu.org/licenses/>.
+
+cmake_minimum_required(VERSION 3.20.0)
+
+# Generate message headers
+set(XML_FILES
+    ${EFC_SOURCE_DIR}/tools/mavlink/message_definitions/v1.0/common.xml
+)
+set(GENERATED_DIR ${CMAKE_BINARY_DIR}/mavlink/generated)
+set(GENERATOR_SCRIPT ${EFC_SOURCE_DIR}/tools/mavlink/pymavlink/tools/mavgen.py)
+
+file(MAKE_DIRECTORY ${GENERATED_DIR})
+
+set(DIALECT_HEADERS "")
+foreach(file ${XML_FILES})
+    get_filename_component(dialect_name ${file} NAME_WLE)
+    set(DIALECT_HEADER ${GENERATED_DIR}/${dialect_name}/${dialect_name}.h)
+
+    add_custom_command(
+        OUTPUT ${DIALECT_HEADER}
+        COMMAND ${VENV_PYTHON} ${GENERATOR_SCRIPT} --lang=C --wire-protocol=2.0 -o ${GENERATED_DIR} ${file}
+        DEPENDS ${file} ${GENERATOR_SCRIPT}
+        COMMENT "Generating mavlink dialect from ${file}"
+        WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
+    )
+
+    list(APPEND DIALECT_HEADERS ${DIALECT_HEADER})
+endforeach()
+
+# Create the library
+add_library(mavlink
+STATIC
+    mavlink.c
+    ${DIALECT_HEADERS} # Only used to make the library depend on all generation steps
+)
+
+target_include_directories(mavlink
+SYSTEM PUBLIC
+    include
+    ${GENERATED_DIR}
+)
+
+target_compile_definitions(mavlink
+PUBLIC
+    # Conversions will be handled using different libraries
+    MAVLINK_NO_CONVERSION_HELPERS=true
+    # Good for both unreliable links and security
+    MAVLINK_CHECK_MESSAGE_LENGTH=true
+    # Use global buffers and statuses per channel, with helpers to point to them
+    # instead of them being defined in every source file mavlink is included in
+    # due to the unfortunate design of mavlink
+    MAVLINK_GET_CHANNEL_STATUS=mavlink_get_channel_status
+    MAVLINK_GET_CHANNEL_BUFFER=mavlink_get_channel_buffer
+)

sitl/external/mavlink/include/mavlink_custom.h

@@ -0,0 +1,27 @@
+/*
+ * This file is part of the efc project <https://github.com/eurus-project/efc/>.
+ * Copyright (c) (2024 - Present), The efc developers.
+ *
+ * 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, version 3.
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __MAVLINK_CUSTOM_H__
+#define __MAVLINK_CUSTOM_H__
+
+#include "mavlink_types.h"
+
+/* Global status and buffer instance getters */
+mavlink_status_t *mavlink_get_channel_status(uint8_t chan);
+mavlink_message_t *mavlink_get_channel_buffer(uint8_t chan);
+
+#endif

sitl/external/mavlink/mavlink.c

@@ -0,0 +1,30 @@
+/*
+ * This file is part of the efc project <https://github.com/eurus-project/efc/>.
+ * Copyright (c) (2024 - Present), The efc developers.
+ *
+ * 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, version 3.
+ *
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+
+#include "mavlink_custom.h"
+
+/* Global status and buffer instances for each channel */
+static mavlink_status_t chan_statuses[MAVLINK_COMM_NUM_BUFFERS];
+static mavlink_message_t chan_buffers[MAVLINK_COMM_NUM_BUFFERS];
+
+mavlink_status_t *mavlink_get_channel_status(uint8_t chan) {
+    return &chan_statuses[chan];
+}
+
+mavlink_message_t *mavlink_get_channel_buffer(uint8_t chan) {
+    return &chan_buffers[chan];
+}