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2020-01-12 10:57:36 -0500 asked a question (ROS in WSL2) + (ROS on Windows) communication

(ROS in WSL2) + (ROS on Windows) communication Hi, everyone. What I really want is to develop in WSL2 ROS, and run Rviz

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2018-02-28 20:26:45 -0500 marked best answer compiling the package [costmap_2d] is extremely slow on Jetson TK1

Have anyone experienced compiling costmap_2d on a Nvidia Jetson TK1 with Ubuntu 16.04 and ROS Kinetic? I've tried to compile it on 2 such boards. They all compiled very very slow! In the extreme case, I tried to compile costmap_2d in my own catkin workspace with the command catkin_make with or without -j5, --use-ninja. In this case, costmap_2d simply failed to finish compiling. It stuck at

Linking CXX executable /home/ubuntu/catkin_ws/devel/lib/costmap_2d/costmap_2d_cloud
Linking CXX executable /home/ubuntu/catkin_ws/devel/lib/costmap_2d/costmap_2d_markers

The linking procedure lasts forever, never succeed to accomplish.

The only way I made it finish is by invoking catkin_make_isolated instead of catkin_make, and the linking still takes very long time when compared to other packages (like lasting 10min+ or so).

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2017-05-28 04:19:04 -0500 edited question rviz marker lifetime has no effect

rviz marker lifetime has no effect Hi, I'm trying to visualize some arbitrary number of markers. Markers were updated e

2017-05-28 04:03:36 -0500 commented question rviz marker lifetime has no effect

Thank you!@gvdhoorn. I did missed that sentence. But I have tested with the modified tutorial code (with unique id), wh

2017-05-28 03:05:56 -0500 asked a question rviz marker lifetime has no effect

rviz marker lifetime has no effect Hi, I'm trying to visualize some arbitrary number of markers. Markers were updated e

2017-04-30 06:24:17 -0500 commented question rviz crash on macOS Sierra

I don't remember how to tweak them all, some tweaks were ugly, so the best way would be run a virtual machine. Developin

2017-04-30 06:18:49 -0500 commented question rviz crash on macOS Sierra

@Gorbag I actually fixed almost every issues, including rviz. But I found it's still inconvenient to run ROS on macOS, s

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2017-04-11 10:46:16 -0500 asked a question static transform broadcaster broadcast wrong time in future

Hi, I'm trying to use static transform broadcaster from the tf2_ros package. But I found the timestamp it broadcasts is in the future!

There are 3 frames involved:

  • The baselink, which is the robot.
  • The scanner frame

The robot is equipped with a laser scanner, which is rigid connected to the baselink. So I used the static_transform_publisher from tf2_ros to publish transform from scanner to baselink.

  • The map frame

A GPS receiver is publishing transform from baselink to map, the fixed frame.

What I'm trying to do is query transform from scanner to map, but ROS complains 'Lookup would require extrapolation into the past', because 'the earliest data is at time 1491920289.300000000' (a time in future). I've printed out current time in the log output, as shown bellow:

[ INFO] [1491920281.359759526]: NOW TIME: 1491920281.359712
[ INFO] [1491920281.359787616]: QUERY TIME (SCANNER): 1491920281.354932
[ INFO] [1491920281.359808455]: QUERY TIME (NAVI): 1491920281.343659
[ WARN] [1491920281.359858387]: Lookup would require extrapolation into the past.  Requested time 1491920281.354932369 but the earliest data is at time 1491920289.300000000, when looking up transform from frame [scanner] to frame [map]

The code used:

  ROS_INFO("NOW TIME: %f", ros::Time::now().toSec());
  ROS_INFO("QUERY TIME (SCANNER): %f", scanner_msg_->header.stamp.toSec());
  ROS_INFO("QUERY TIME (NAVI): %f", navi_msg_->header.stamp.toSec());
  geometry_msgs::TransformStamped scanner2world_msg;
  try
  {
    scanner2world_msg =
        tfBuffer_.lookupTransform(world_frame_id_, scanner_frame_id_,
                                  scanner_msg_->header.stamp);
  }
  catch (tf2::TransformException &ex)
  {
    ROS_WARN("%s", ex.what());
    return;
  }

Most interesting thing is the ros::Time::now().toSec() part. It shows now time is the 'pasted' time of published transform. How could this be possible?

I thought static transform is so simple that the provided static_transform_broadcaster should be reliable. But it turns out I have to drop using it by writing my own broadcaster. This is annoying, because it is such a common need to broadcast static transforms that should be addressed cleanly by static_transform_broadcaster.

Am I doing something wrong?

Thank you for any help!

Brgs! - ZOU Lu

2017-03-04 05:17:53 -0500 commented question ROS ate my network bandwidth!

I stoped other subscribers before rostopic bw, and that command is issued on the same box of the publisher, which means this portion of traffic would go to lo instead of eth0, am I right?

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2017-03-03 11:07:32 -0500 commented question ROS ate my network bandwidth!

@gvdhoorn, thank you. I used nload eth0 to measure the specific traffic on the interface eth0, so lo is not taken into account. When I used all the 3 cameras, the network load was pushed to its limit very quickly, then the camera capturing node died because of couldn't connect to master node

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2017-03-03 07:39:17 -0500 asked a question ROS ate my network bandwidth!

Sorry for the title, no offence. I'm just crazy about the problem.

I have 2 computers, A and B connected via a 1000Mbps network connection, 3 network cameras were connected to this network.

I was trying to capture images in computer A, and publish the images via ROS, so the computer B could receive a copy simultaneously.

Here is the weird thing I've encountered:

If the IN-COMING bandwidth of B is ~400Mbps, then the OUT-GOING bandwidth of A would be ~800Mbps, that said, A is sending twice as much data as needed by B. What's wrong with it??? I've tested the bandwidth usage by the command rostopic bw /the_image_topic, and the result on both A and B are all ~400Mbps.

I'm very sure that there's no other subscriber on the network, as when I stop the subscriber on B, the network traffic drops down to nearly zero immediately.

In case there's some bugs lie in the camera driver, I wrote a very simple program to publish some Lidar data from pre-recorded Lidar files. And I could observe the same issue is still there, or even worse, this time the ratio of out-going/in-coming is very near to 3/1 ...

Can anyone help me with this problem? The bandwidth is far from sufficient to support 3 cameras simultaneously, it's currently the bottleneck of my system. Many thanks for any kinds of help!

2017-02-15 20:35:38 -0500 marked best answer building ROS on macOS 10.12 at `qt_gui_cpp`

Hi, there

I'm following the tutorial Installation Instructions for Kinetic in OS X to get ROS up and running on my Mac. However, I failed (and tried so much methods to solve, still failed) at building qt_gui_cpp when executing:

./src/catkin/bin/catkin_make_isolated --install -DCMAKE_BUILD_TYPE=Release

I bet the problems lie at the package sip (installed via brew) or catkin_ws/src/python_qt_binding, because the failed codes are generated from sip, related error output is like this (with VERBOSE=ON):

[  5%] Linking CXX shared library /Users/victor/Repo/ros/ros_catkin_ws/devel_isolated/qt_gui_cpp/lib/libqt_gui_cpp.dylib
cd /Users/victor/Repo/ros/ros_catkin_ws/build_isolated/qt_gui_cpp/src/qt_gui_cpp && /usr/local/Cellar/cmake/3.7.1/bin/cmake -E cmake_link_script CMakeFiles/qt_gui_cpp.dir/link.txt --verbose=ON
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/c++  -std=c++11 -fPIC -O3 -DNDEBUG -dynamiclib -Wl,-headerpad_max_install_names  -o /Users/victor/Repo/ros/ros_catkin_ws/devel_isolated/qt_gui_cpp/lib/libqt_gui_cpp.dylib -install_name /Users/victor/Repo/ros/ros_catkin_ws/devel_isolated/qt_gui_cpp/lib/libqt_gui_cpp.dylib CMakeFiles/qt_gui_cpp.dir/composite_plugin_provider.cpp.o CMakeFiles/qt_gui_cpp.dir/generic_proxy.cpp.o CMakeFiles/qt_gui_cpp.dir/plugin_bridge.cpp.o CMakeFiles/qt_gui_cpp.dir/plugin_context.cpp.o CMakeFiles/qt_gui_cpp.dir/plugin_descriptor.cpp.o CMakeFiles/qt_gui_cpp.dir/plugin_provider.cpp.o CMakeFiles/qt_gui_cpp.dir/recursive_plugin_provider.cpp.o CMakeFiles/qt_gui_cpp.dir/settings.cpp.o CMakeFiles/qt_gui_cpp.dir/__/__/include/qt_gui_cpp/moc_plugin.cpp.o CMakeFiles/qt_gui_cpp.dir/__/__/include/qt_gui_cpp/moc_plugin_bridge.cpp.o CMakeFiles/qt_gui_cpp.dir/__/__/include/qt_gui_cpp/moc_plugin_context.cpp.o /usr/local/lib/libboost_filesystem-mt.dylib /usr/local/lib/libtinyxml.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/libclass_loader.dylib /usr/local/lib/libPocoFoundation.dylib /usr/lib/libdl.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/librosconsole.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/librosconsole_log4cxx.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/librosconsole_backend_interface.dylib /usr/local/lib/liblog4cxx.dylib /usr/local/lib/libboost_regex-mt.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/librostime.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/libcpp_common.dylib /usr/local/lib/libboost_system-mt.dylib /usr/local/lib/libboost_thread-mt.dylib /usr/local/lib/libboost_chrono-mt.dylib /usr/local/lib/libboost_date_time-mt.dylib /usr/local/lib/libboost_atomic-mt.dylib /usr/local/lib/libconsole_bridge.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/libroslib.dylib /usr/local/lib/libboost_filesystem-mt.dylib /usr/local/lib/libboost_system-mt.dylib /usr/local/lib/QtWidgets.framework/QtWidgets /usr/local/lib/libtinyxml.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/libclass_loader.dylib /usr/local/lib/libPocoFoundation.dylib /usr/lib/libdl.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/librosconsole.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/librosconsole_log4cxx.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/librosconsole_backend_interface.dylib /usr/local/lib/liblog4cxx.dylib /usr/local/lib/libboost_regex-mt.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/librostime.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/libcpp_common.dylib /usr/local/lib/libboost_thread-mt.dylib /usr/local/lib/libboost_chrono-mt.dylib /usr/local/lib/libboost_date_time-mt.dylib /usr/local/lib/libboost_atomic-mt.dylib /usr/local/lib/libconsole_bridge.dylib /Users/victor/Repo/ros/ros_catkin_ws/install_isolated/lib/libroslib.dylib /usr/local/lib/QtGui.framework/QtGui /usr ...
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2017-01-15 01:56:08 -0500 marked best answer rviz crash on macOS Sierra

Hi,

After lots of tweaks, I've finally made it to setup ROS Kinetic on my MacBook Air, with mac OS Sierra. Everything works fine except rviz. It crashes on startup. I tried with this command:

rosrun rviz rviz -l

And the output is:

[ INFO] [1482424510.671672000]: rviz version 1.12.4
[ INFO] [1482424510.671803000]: compiled against Qt version 5.7.0
[ INFO] [1482424510.671830000]: compiled against OGRE version 1.7.4 (Cthugha)
libpng warning: iCCP: known incorrect sRGB profile
libpng warning: iCCP: known incorrect sRGB profile
[ INFO] [1482424511.705687000]: Creating resource group General
[ INFO] [1482424511.705788000]: Creating resource group Internal
[ INFO] [1482424511.705827000]: Creating resource group Autodetect
[ INFO] [1482424511.705940000]: SceneManagerFactory for type 'DefaultSceneManager' registered.
[ INFO] [1482424511.706240000]: Registering ResourceManager for type Material
[ INFO] [1482424511.706289000]: Registering ResourceManager for type Mesh
[ INFO] [1482424511.706321000]: Registering ResourceManager for type Skeleton
[ INFO] [1482424511.706382000]: MovableObjectFactory for type 'ParticleSystem' registered.
[ INFO] [1482424511.706445000]: OverlayElementFactory for type Panel registered.
[ INFO] [1482424511.706476000]: OverlayElementFactory for type BorderPanel registered.
[ INFO] [1482424511.706510000]: OverlayElementFactory for type TextArea registered.
[ INFO] [1482424511.706549000]: Registering ResourceManager for type Font
[ INFO] [1482424511.706587000]: ArchiveFactory for archive type FileSystem registered.
[ INFO] [1482424511.706612000]: ArchiveFactory for archive type Zip registered.
[ INFO] [1482424511.706637000]: DDS codec registering
[ INFO] [1482424511.706691000]: FreeImage version: 3.17.0
[ INFO] [1482424511.706724000]: This program uses FreeImage, a free, open source image library supporting all common bitmap formats. See http://freeimage.sourceforge.net for details
[ INFO] [1482424511.706908000]: Supported formats: bmp,ico,jpg,jif,jpeg,jpe,jng,koa,iff,lbm,mng,pbm,pbm,pcd,pcx,pgm,pgm,png,ppm,ppm,ras,tga,targa,tif,tiff,wap,wbmp,wbm,psd,cut,xbm,xpm,gif,hdr,g3,sgi,rgb,rgba,bw,exr,j2k,j2c,jp2,pfm,pct,pict,pic,3fr,arw,bay,bmq,cap,cine,cr2,crw,cs1,dc2,dcr,drf,dsc,dng,erf,fff,ia,iiq,k25,kc2,kdc,mdc,mef,mos,mrw,nef,nrw,orf,pef,ptx,pxn,qtk,raf,raw,rdc,rw2,rwl,rwz,sr2,srf,srw,sti,x3f,webp,jxr,wdp,hdp
[ INFO] [1482424511.706943000]: Registering ResourceManager for type HighLevelGpuProgram
[ INFO] [1482424511.707169000]: Registering ResourceManager for type Compositor
[ INFO] [1482424511.707464000]: MovableObjectFactory for type 'Entity' registered.
[ INFO] [1482424511.707513000]: MovableObjectFactory for type 'Light' registered.
[ INFO] [1482424511.707546000]: MovableObjectFactory for type 'BillboardSet' registered.
[ INFO] [1482424511.707575000]: MovableObjectFactory for type 'ManualObject' registered.
[ INFO] [1482424511.707607000]: MovableObjectFactory for type 'BillboardChain' registered.
[ INFO] [1482424511.707636000]: MovableObjectFactory for type 'RibbonTrail' registered.
[ INFO] [1482424511.707859000]: *-*-* OGRE Initialising
[ INFO] [1482424511.707901000]: *-*-* Version 1.7.4 (Cthugha)
[ INFO] [1482424511.707944000]: Loading library /usr/local/Cellar/ogre/1.7.4/lib/libRenderSystem_GL
[ INFO] [1482424511.715310000]: Installing plugin: GL RenderSystem
[ INFO] [1482424511.715470000]: OpenGL Rendering Subsystem created.
[ INFO] [1482424511.715731000]: Plugin successfully installed
[ INFO] [1482424511.715784000]: Loading library /usr/local/Cellar/ogre/1.7.4/lib/libPlugin_OctreeSceneManager
[ INFO] [1482424511.722139000]: Installing plugin: Octree & Terrain Scene Manager
[ INFO] [1482424511.722224000]: Plugin successfully installed
[ INFO] [1482424511.722266000]: Loading library /usr/local/Cellar/ogre/1.7.4/lib/libPlugin_ParticleFX
[ INFO] [1482424511.728896000]: Installing plugin: ParticleFX
[ INFO] [1482424511.728966000]: Particle ...
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2017-01-09 08:53:19 -0500 commented answer Compiling ROS Kinetec from source fails when building image_proc

BTW, I hate vtk, they love to change things, always like playing a solo

2017-01-09 08:51:58 -0500 commented answer Compiling ROS Kinetec from source fails when building image_proc

I suppose vtk has changed its structure in the new version, e.g. move vtkOBJReader into a sub library vtkIOGeometry, so you have to tell cmake to find vtkIOGeometry if you want to use that class.

Arch always uses the newest, that's why you'll encounter such issue earlier than others.

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2017-01-08 19:13:40 -0500 answered a question Compiling ROS Kinetec from source fails when building image_proc

modify opencv3/cmake/OpenCVDetectVTK.cmake, for every find_package(VTK QUIET COMPONENTS ... add an entry vtkIOGeometry

This works for me