clever: Move udev rule file, add note to readme

README.md

@@ -59,6 +59,15 @@ To complete `mavros` install you'll need to install `geographiclib` datasets:
 curl https://raw.githubusercontent.com/mavlink/mavros/master/mavros/scripts/install_geographiclib_datasets.sh | sudo bash
 ```
 
+You may optionally install udev rules to provide `/dev/px4fmu` symlink to your PX4-based flight controller connected over USB. Copy `99-px4fmu.rules` to your `/lib/udev/rules.d` folder:
+
+```bash
+cd ~/catkin_ws/src/clever/clever/config
+sudo cp 99-px4fmu.rules /lib/udev/rules.d
+```
+
+Alternatively you may change the `fcu_url` property in `mavros.launch` file to point to your flight controller device.
+
 ## Running
 
 Enable systemd service `roscore` (if not running):
@@ -80,6 +89,8 @@ To start connection to the flight controller, use:
 roslaunch clever clever.launch
 ```
 
+> Note that the package is configured to connect to `/dev/px4fmu` by default (see [previous section](#manual-installation)). Install udev rules or specify path to your FCU device in `mavros.launch`.
+
 Also, you can enable and start the systemd service:
 
 ```bash

builder/image-build.sh

@@ -116,7 +116,7 @@ ${BUILDER_DIR}/image-chroot.sh ${IMAGE_PATH} copy ${SCRIPTS_DIR}'/assets/ros_pyt
 ${BUILDER_DIR}/image-chroot.sh ${IMAGE_PATH} copy ${SCRIPTS_DIR}'/assets/pigpiod.service' '/lib/systemd/system/'
 # ${BUILDER_DIR}/image-chroot.sh ${IMAGE_PATH} copy ${SCRIPTS_DIR}'/assets/kinetic-ros-clever.rosinstall' '/home/pi/ros_catkin_ws/'
 # Add PX4 udev rules
-${BUILDER_DIR}/image-chroot.sh ${IMAGE_PATH} copy ${SCRIPTS_DIR}'/assets/99-px4fmu.rules' '/lib/udev/rules.d/'
+${BUILDER_DIR}/image-chroot.sh ${IMAGE_PATH} copy ${REPO_DIR}'/clever/config/99-px4fmu.rules' '/lib/udev/rules.d/'
 # Add rename script
 ${BUILDER_DIR}/image-chroot.sh ${IMAGE_PATH} copy ${SCRIPTS_DIR}'/assets/clever_rename' '/usr/local/bin/clever_rename'
 ${BUILDER_DIR}/image-chroot.sh ${IMAGE_PATH} exec ${SCRIPTS_DIR}'/image-ros.sh' ${REPO_URL} ${IMAGE_VERSION} false false ${NUMBER_THREADS}

clever/CMakeLists.txt

@@ -227,6 +227,19 @@ target_link_libraries(clever
 #   DESTINATION ${CATKIN_PACKAGE_SHARE_DESTINATION}
 # )
 
+# Only install udev rules when building a Debian package
+# FIXME: Other operating systems may have other prefixes
+string(FIND ${CMAKE_INSTALL_PREFIX} "/opt/ros" _PREFIX_INDEX)
+if (${_PREFIX_INDEX} EQUAL 0)
+  message(STATUS "Building as a Debian package - adding udev rules as installable files")
+  install(FILES
+    config/99-px4fmu.rules
+    DESTINATION /lib/udev/rules.d
+  )
+else()
+  message(STATUS "Building in a user workspace - not adding udev rules")
+endif()
+
 #############
 ## Testing ##
 #############