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You can always use standard serial I/O for communicating with serial devices from a ROS node; ROS serial is a mechanism through which you can program any two systems that can communicate via serial to use ROS' API instead of bothering to deal with low level serial port I/O.

Specifically, in your case your motor controller will most probably come with a SDK of sorts that deals with sending motor commands over a serial port. You would simply use that API within your ROS node on your laptop to communicate with the motor controller.

ROS Serial would be useful if you were to write your motor controller from scratch on say an Arduino, and wanted to easily communicate with ROS devices over the serial port using the ROS Serial API.

Hi all I just installed an Electric desktop-full as per the instructions on an x86_64 Fedora 15 installation. ROS seems to have installed fine. However, whenever I attempt a rosmake simulator_gazebo, or any other package that requires eigen as a dependency, I get the error

rosdep install ERROR:
failed to install eigen

I have eigen3-devel installed (eigen3-devel-3.0.0-2.fc15.noarch) and don't really have a clue how to go about this, as apparently eigen doesn't have any compiled libraries, only the headers.

Can anyone help? Thanks!

UPDATE: It seems that the warning is thrown only because it can't really find it by the name it's looking for. For example, after a little playing around, I could get vision_opencv working.

UPDATE 2 : Now after quite a few hours, I'm stuck at a cmake stage. Had to install yampl-cpp-devel, tinyxml-devel, vtk-devel, libyaml-devel, rosdep install for gazebo_tools, build assimp, copied the /usr/include/ffmpeg/* to /usr/include (to fix missing avformat.h), hdf5-devel, [added -ltinyxml flag to /gazebo/build/CMakeCache.txt (and in gazebo_tools), added a VTK_DIR:FILEPATH=/usr/lib64/vtk-5.6 to pcl_ros/CMakeCache.txt ... Didnt work], used http://www.cmake.org/pipermail/cmake/2006-March/008633.html and changed VTK REQUIRED to VTK5 required in the cmake files. Also changed the path in the URL file to point to lib64/vtk-5.6

This fixed the missing VTK errors, but I'm repeatedly stuck with the tinyXML errors.

/usr/bin/ld: note: 'TiXmlElement::SetAttribute(std::basic_string<char,std::char_traits<char>, std::allocator<char> > const&, std::basic_string<char,    std::char_traits<char>, std::allocator<char> > const&)' is defined in DSO /usr/lib64/libtinyxml.so.0 so try adding it to the linker command line
/usr/lib64/libtinyxml.so.0: could not read symbols: Invalid operation

I also get a (possibly related because it involves pcl_ros_tf)

  [ 28%] Built target rosbuild_precompile
  Linking CXX shared library lib/libvision_reconfigure.so
  /usr/bin/ld: cannot find -lpcl_ros_tf
  collect2: ld returned 1 exit status
  make[2]: *** [lib/libvision_reconfigure.so] Error 1
  make[1]: *** [CMakeFiles/vision_reconfigure.dir/all] Error 2

Where do I add the -ltinyxml flag?

So, I've been building ROS on Fedora 15, and there are a few persistent issues that keep cropping up every time the ROS source code is updated.

The most annoying issue is concerning the version of the Boost libraries used in the code. A bit of googling brought me here which made me realize that this was an issue with the changeover from boost::filesystem from v2 to v3, and so I had to add a #define BOOST_FILESYSTEM_VERSION 2 to all files including a #include <boost/filesystem.hpp>. To find these files, I used

find . | xargs grep 'boost/filesystem.hpp' -sl

this gave me about 9 files which I modified, and ran the script again.

Do I report this as an issue?

Additionally, unlike ubuntu all the packages/stacks are not rosmake'd on install. For example, for image_view, I need to rosmake image_views and the plugins and opencv2 (For which I had to do the same Boost thing to boost_fs_wrapper.cpp)

Just built everything from scratch (after lots of pain), and yes it works now.

Bump. Similar issue on Groovy on an Odroid XU. Using the ahendrix repo

If there's a specific package broken please file tickets for the specific package. The transition from boost filesystem 2 -> 3 is going to be generally painful and each usage will likely have to have ifdef logic for a while.

The rosmake is true on any system where you are installing from source. You need to compile all the packages you expect to use.

Use a NonLoopback server address when you create one. You could use something like

Roscore _core = RosCore.newPublic(11411);

To fix the libtinyxml issue, apparently the build process doesn't look at the lib64 folder. So, I added to CMakeLists.txt

set(GAZEBO_LDFLAGS_OTHERS -L/usr/lib64 -ltinyxml)
set(GAZEBO_INCLUDE_DIRS ${GAZEBO_INCLUDE_DIRS} /usr/include)

to the beginning, and a

  rosbuild_add_link_flags(bin/urdf2model ${GAZEBO_LDFLAGS_OTHERS})

for the urdf2model executable

I also had to something very similar in gazebo_tools, same initial commands, and a

rosbuild_add_link_flags(bin/urdf2model ${GAZEBO_LDFLAGS_OTHERS})

For the pcl_ros_tf, apparently an old failed build was blocking a successful build, and so a delete of the build and the CMakeFiles folder and a subsequent rosmake did the job.