roslaunch failed: cannot launch node - beagleboneblack

Question

I have downloaded and compiled some Ros nodes from here (just to have more info). I am trying to launch the five ROS nodes with parameters using a launchfile that is taken from that repo.
After executing source catkin_ws/devel_isolated/setup.bash and executing roslaunch crab.launch(the launch file from the link above) the next error appears:
root#beaglebone:~# roslaunch crab.launch
... logging to /root/.ros/log/4f6332fe-dbe2-11e3-86a8-7ec70b079d59/roslaunch-beaglebone-2067.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.
started roslaunch server http://beaglebone:58881/
SUMMARY
========
PARAMETERS
* /clearance
* /duration_ripple
* /duration_tripod
* /joint_lower_limit
* /joint_upper_limit
* /port_name
* /robot_description
* /rosdistro
* /rosversion
* /trapezoid_h
* /trapezoid_high_radius
* /trapezoid_low_radius
NODES
/
crab_body_kinematics (crab_body_kinematics/body_kinematics)
crab_gait (crab_gait/gait_kinematics)
crab_imu (crab_imu/imu_control)
crab_leg_kinematics (crab_leg_kinematics/leg_ik_service)
crab_maestro_controller (crab_maestro_controller/controller_sub)
ROS_MASTER_URI=http://localhost:11311
core service [/rosout] found
ERROR: cannot launch node of type [crab_leg_kinematics/leg_ik_service]: can't locate node [leg_ik_service] in package [crab_leg_kinematics]
ERROR: cannot launch node of type [crab_maestro_controller/controller_sub]: can't locate node [controller_sub] in package [crab_maestro_controller]
ERROR: cannot launch node of type [crab_body_kinematics/body_kinematics]: can't locate node [body_kinematics] in package [crab_body_kinematics]
ERROR: cannot launch node of type [crab_gait/gait_kinematics]: can't locate node [gait_kinematics] in package [crab_gait]
ERROR: cannot launch node of type [crab_imu/imu_control]: can't locate node [imu_control] in package [crab_imu]
I have reinstalled the packages as suggested in some other threats about similar problems.
I also have noticed that
1º- if I move all the executablesof the nodes to the folder src/<package>/, I'm able to execute roslaunch crab.launch. But I don´t want to leave it like that, not proper way to work ;)
Additional info:
2º- If I execute, for example, source devel_isolated/<package>/setup.bashand then roslaunch crab.launch, the package which I have just source-d works and executes... (while the other still don't)
3º- So I have source-d all the source devel_isolated/<package>/setup.bash and try again: no one worked this time.
This leads to think that the problems are due to ROS variable enviroment: if I make an export | grep ROSafter 2º, I can see that the package path appears in $ROS_PATH-s and the others are not there:
root#beaglebone:~# export | grep ROS
declare -x ROS_DISTRO="hydro"
declare -x ROS_ETC_DIR="/opt/ros/hydro/etc/ros"
declare -x ROS_MASTER_URI="http://localhost:11311"
declare -x ROS_PACKAGE_PATH="/root/catkin_ws/src/crab_msgs:/root/catkin_ws/src/joy:/root/catkin_ws
/src/ps3joy:/root/catkin_ws/src/xacro:/root/catkin_ws/src/roslint:/root/catkin_ws/src/kdl_parser:/root/catkin_ws
/src/urdf:/root/catkin_ws/src/urdf_parser_plugin:/root/catkin_ws/src:/opt/ros/hydro/share:/opt/ros/hydro
/stacks:/root/ros_catkin_ws/install_isolated/share:/root/ros_catkin_ws/install_isolated/stacks"
declare -x ROS_ROOT="/opt/ros/hydro/share/ros"
declare -x ROS_TEST_RESULTS_DIR="/root/catkin_ws/build_isolated/crab_msgs/test_results"
root#beaglebone:~# source catkin_ws/devel_isolated/crab_imu/setup.bash
declare -x ROS_PACKAGE_PATH="/root/catkin_ws/src/crab_imu:/root/catkin_ws/src/crab_msgs:/root/catkin_ws
/src/joy:/root/catkin_ws/src/ps3joy:/root/catkin_ws/src/xacro:/root/catkin_ws/src/roslint:/root/catkin_ws
/src/kdl_parser:/root/catkin_ws/src/urdf:/root/catkin_ws/src/urdf_parser_plugin:/root/catkin_ws/src:/opt
/ros/hydro/share:/opt/ros/hydro/stacks:/root/ros_catkin_ws/install_isolated/share:/root/ros_catkin_ws
/install_isolated/stacks"
declare -x ROS_TEST_RESULTS_DIR="/root/catkin_ws/build_isolated/crab_imu/test_results"
Seems that 3º overwrites the source executed before..., meaning that in ROS_PACKAGE_PATHdoes not appear all he packages as they should.
I also have tried to force ROS_PACKAGE_PATHusing exportcommand, but it didn't work. So, I have to change more environment variables apart from that, but don't know which one...
So, I don't know if I diagnosis is correct and, if so, what should I do to correct this... Hope I have gathered enough info.
Thanks in advance!!
Iñigo

Answer 1

set the executable bit for files. most probably you need to set executable permissions for files.
chmod +x filename.