FAQ

Content:

• Installation
• Miscellaneous

Installation

Q: Why do I get missing dependencies when building the maplab workspace?

Some of our current dependencies include further catkin packages, which are not a dependency of maplab. If you build the complete workspace, these packages will fail due to missing dependencies of their own. This might change in the future, but for now there are two options:

Please only build maplab: catkin build maplab

or

Add CATKIN_IGNORE packages to the superfluous packages.

Q: Why are the dependencies in a separate repository and not submodules in maplab?

The decision to move the dependencies to a separate repository was motivated by the fact that someone might want to integrate maplab in their existing catkin workspace. This will require some additional effort, however, having an external dependencies-repository should make it easier to combine the maplab dependencies with the dependencies of the existing workspace.

Q: Compilation failed because protoc was not found.

If you get an issue similar to this:

make[2]: /home/user/maplab_ws/devel/.private/maplab_common/bin/protoc: Command not found
make[2]: *** [compiled_proto/maplab-common/id.pb.cc] Error 127
make[2]: *** Waiting for unfinished jobs....

Make sure that your workspace layout is merge:

cd ~/$CATKIN_WS
catkin clean  # Necessary to clean up your workspace as your layout will change.
catkin config --merge-devel

You can check if your workspace is properly set up by running:

$ catkin config
---------------------------------------------------------------------------
Profile:                     default
Extending:        [explicit] /opt/ros/kinetic
Workspace:                   /home/user/maplab_ws
---------------------------------------------------------------------------
...
---------------------------------------------------------------------------
Devel Space Layout:          merged    # <-- This should say `merged`.
Install Space Layout:        None
---------------------------------------------------------------------------
...

Q: Why is my opencv3_catkin build freezing?

A known cause for this is an installed MATLAB using a network licence. The build can stall on getting the licence authenticated; so make sure that the licence server can be accessed, connect to the VPN if required.

Q: I get an error for libGL.so with Nvidia drivers

make[5]: *** No rule to make target '/usr/lib/x86_64-linux-gnu/libGL.so', needed by 'lib/libopencv_viz.so.3.2.0'.  Stop.

consider redefining the symbolic link that somehow got lost in your Ubuntu by:

sudo rm /usr/lib/x86_64-linux-gnu/libGL.so
sudo ln -s /usr/lib/libGL.so.1 /usr/lib/x86_64-linux-gnu/libGL.so

Q: ImportError: No module named 'requests'

Install requests by calling:

sudo pip install requests

Miscellaneous

Q: Why the sheep?

That's why: