slot_stream_data.connect ("/ kobuki / stream_data") sigslot connection failure about kobuki_core

[stonier]

Taking the simple loop program here and throwing in a ecl::SigSlotsManager<>::printStatistics(); at the end of the constructor I get:

Topics
  Name: /kobuki/controller_info
    # Subscribers: 0
    # Publishers : 1
  Name: /kobuki/stream_data
    # Subscribers: 1
    # Publishers : 1

Possible problems:

1. You're not calling kobuki.init(parameters) anywhere
2. The parameters are invalid (init will return with an exception, see here)

[hanxia312]

I'm going crazy, when i'm in kobuki.cpp
Kobuki :: init (Parameters & parameters) {
...
Thread.start (& Kobuki :: spin, * this);
Ecl :: SigSlotsManager <> :: printStatistics ();
}
The print value is:
Topics
Name: / kobuki / controller_info
# Subscribers: 0
# Publishers: 1
Name: / kobuki / stream_data
# Subscribers: 0
# Publishers: 1
But when i am in simple_loop.cpp

Kobuki.init (parameters);
ecl :: SigSlotsManager <> :: printStatistics ();
prints the result:
Topics

The parameters are valid in kobuki.cpp, but in simple_loop.cpp call Kobuki.init(parameters) function, Topics did not print. Looking forward to your reply, thank you
By the way, this kobuki project is my cross compiler arm so library running on the development board.
Cross-compilation steps:
cd ~ / kobuki_core
export PATH = ~ / kobuki_core / src / catkin / bin /: $ {PATH}
catkin_make -DCMAKE_TOOLCHAIN_FILE = ~ / kobuki_core / src / catkin / catkin.toolchain.cmake
cd build;make install

catkin.toolchain.cmake:
SET (CMAKE_SYSTEM_NAME Linux)
SET (CMAKE_C_COMPILER "/ usr / bin / my-ndk-toolchain / bin / arm-linux-androideabi-gcc")
SET (CMAKE_CXX_COMPILER "/ usr / bin / my-ndk-toolchain / bin / arm-linux-androideabi-g ++")
SET (CMAKE_FIND_ROOT_PATH "/ usr / bin / my-ndk-toolchain / sysroot /")

[stonier]

Try without the cross compiler. This shouldn't have any relation, but first thing to do when you have a problem that has no immediate leads - simplify what you are doing until something comes up.

Which branches of ecl and kobuki are you using?

[hanxia312]

thank you very much for your reply! without cross compile and run simple_loop.cpp this project is successful. How do I run this project using cross compilation? Is there a problem with my cross-compilation steps? Ecl and kobuk's branch is downloaded at ：
http://yujinrobot.github.io/kobuki/doxygen/enInstallationLinuxGuide.html

https://raw.githubusercontent.com/yujinrobot/kobuki_core/hydro/kobuki_core.rosinstall

Kobuki Core / Yujin stacks

• git: {local-name: catkin, version: 0.5.73, uri: 'https://github.com/ros/catkin.git'}
• git: {local-name: ecl_tool, version: 0.60.0, uri: 'https://github.com/stonier/ecl_tools.git'}
• git: {local-name: ecl_lite, version: 0.60.0, uri: 'https://github.com/stonier/ecl_lite.git'}
• git: {local-name: ecl_core, version: 0.60.5, uri: 'https://github.com/stonier/ecl_core.git'}
• git: {local-name: ecl_navigation, version: 0.60.0, uri: 'https://github.com/stonier/ecl_navigation.git'}
• git: {local-name: kobuki_core, version: hydro, uri: 'https://github.com/yujinrobot/kobuki_core.git'}

Looking forward to your reply！

[stonier]

Ach, pretty old sources. Yujin hasn't had anyone updating those...

All of those libraries are very stable, but there has been a few bugfixes over the years...I'd try the latest releases (used in ROS kinetic):

• git: {local-name: catkin, version: kinetic-devel, uri: 'https://github.com/ros/catkin.git'}
• git: {local-name: ecl_tool, version: release/0.61-indigo-kinetic, uri: 'https://github.com/stonier/ecl_tools.git'}
• git: {local-name: ecl_lite, version: release/0.61-indigo-kinetic, uri: 'https://github.com/stonier/ecl_lite.git'}
• git: {local-name: ecl_core, version: release/0.61-indigo-kinetic, uri: 'https://github.com/stonier/ecl_core.git'}
• git: {local-name: ecl_navigation, version: release/0.60-indigo-kinetic, uri: 'https://github.com/stonier/ecl_navigation.git'}
• git: {local-name: kobuki_core, version: kinetic, uri: 'https://github.com/yujinrobot/kobuki_core.git'}

Looks like you're using the ndk cross compiler - making an android app based on the c++ lib? I think you're the first to try that I know of. Another company made a very simple java driver at one point but this should be better if it works. At any rate, it looks like sigslot publishers are not working for some reason. These are not rocket science though, but it might be that the NDK is having trouble with some of the template programming.

Can you create a very simple program that creates a signal and prints the statistics? Verify that it works on the non-cross compile and that it fails on the cross-compile. Then we can dig further there. I'd like to reproduce it here, but I don't have all of the infra/know how to get that running and to test it.

[stonier]

That rosinstall has been updated... https://raw.githubusercontent.com/yujinrobot/kobuki_core/devel/kobuki_core.rosinstall

[stonier]

Original problem has been resolved earlier in the thread.