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2012-08-03 02:46:42 -0500 asked a question Is there a way to watch service calls?

One of the features I love about ROS's publisher-subscriber design is that I can passively "tune in" to the streams of communication between nodes to better understand their interaction. I have yet to find a convenient way to do the same for services.

I'm working on writing a man-in-the-middle node that could allow me to do this, but this seems like something ROS might provide already. Another option that I have yet to explore is using a debugger, but this could become tedious for a large software pipeline. Does anyone know of something better?

If it informs your answer, I'd like to use parts of the arm_navigation pipeline with existing motor controllers that do not conform to ROS's PR2 controller interface. Thanks

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2012-07-18 23:30:56 -0500 marked best answer [RGDBSLAM installation] missing gsl/gsl_linalg.h

OS: Clean Ubuntu 11.10
ROS version: Electric

I'm trying to install RGBDSLAM for the first time and I'm mystified. I've followed the installation instructions on the ROS Wiki without issue until step 3.2, but when I execute the line
rosmake --rosdep-install rgbdslam
it fails with this line
~/ros/rgbdslam/external/gicp/optimize.h:44:28: fatal error: gsl/gsl_linalg.h: No such file or directory

Any ideas how to fix this? Let me know if there's more diagnostic info that might help

2012-07-11 08:28:16 -0500 commented answer Interpreting stored cloud file from PointCloud2 data type

Thanks, hadn't come across that. good to know

2012-07-11 05:54:09 -0500 answered a question Interpreting stored cloud file from PointCloud2 data type

There is probably a more direct method, but I've used PCL's .pcd format to accomplish this.

EDIT: Dan Lazewatsky pointed out pointcloud_to_pcd, which converts a ROS PointCloud2 msg to a .pcd file. See his comment for the docs.

Once you have it as a .pcd, it should be fairly easy to parse. After the header the points are listed one per line: x y z rgb. Note that PCL packs the RBG (and alpha, if you're using it) channels into a single float.

Related docs and tutorials: pcl::fromROSmsg | writing to a .pcd file | .pcd file format

2012-07-11 03:31:55 -0500 commented answer Asus Xtion camera calibration fails to start.

(Also on Fuerte) Worked for me, thanks! I didn't need the --no-service-check, just the switch from image:=/camera/rgb/image_raw to /camera/rgb/image_mono

2012-06-29 08:13:40 -0500 marked best answer Trouble configuring libdc1394 for Bumblebee2

OS: Ubuntu 11.10
ROS: Fuerte
Camera: Point Grey's Bumblebee2 BB2-08S2M
Other software:
- Columbia University's bumblebee2 ROS package (with a few modifications described below)
- libdc1394-22 (ver. 2.1.3-4)
- Coriander (for checking that the camera can communicate with the computer)

I'm running into errors and I believe they stem from configuring the libdc1394 library. I installed the bumblebee2 package from above, following the excellent tutorial found here. I modified a few parts of the package code to update it to work with Fuerte, which involved a few additional #includes and commenting out the sensor_msgs::Image.set_data_size() function calls, as that function no longer exists. Also, my camera's resolution is 1024x768 @ 20 fps, and I made changes from the tutorial accordingly.

So, when I run the roslaunch camera1394 startcamera.launch, I get the following kicked back from libdc1394:

libdc1394 error: Format_7 Error_flag_1 is set: in _dc1394_v130_handshake (format7.c, line 122): invalid image position, size, color coding or ISO speed

I know that it is possible to get it to work; using Coriander (which makes use of the same library), I've seen stereo images streaming from the camera. I narrowed it down to a call to the function dc1394_format7_set_roi() from dev_camera1394.cpp within the bumblebee2 package. This function appears to set multiple options the specify the camera configuration, and by splitting these up in to separate function calls, I believe it is the color coding that is causing it. My current code:

....
dc1394_format7_set_image_size(camera_, videoMode_, 1024, 768); dc1394_format7_set_packet_size(camera_, videoMode_, DC1394_USE_MAX_AVAIL); dc1394_format7_set_color_coding(camera_, videoMode_, DC1394_COLOR_CODING_RAW16);
....

And the last call there results in the following errors:

libdc1394 error: Format_7 Error_flag_1 is set: in _dc1394_v130_handshake (format7.c, line 122): invalid image position, size, color coding or ISO speed

libdc1394 error: Format_7 Error_flag_1 is set: in dc1394_format7_set_color_coding (format7.c, line 493): F7 handshake failure

So, it appears to be the color coding, but the camera's spec says it uses Raw16. I've tried Raw8 and Mono8 with the same results. Now I'm at a loss. Anyone have any ideas, or experience with Bumblebees and ROS? Thanks, and let me know if more information will help!

2012-06-28 10:20:05 -0500 commented answer Update Fuerte to 1.8.10 breaks rospkg

Sorry to be a newbie, but how do I get rid of the easy_install version? easy_inst's help says nothing about uninstalling. And mine was a fresh reinstallation of ROS, but not Ubuntu. After this, dpkg no longer reports ros-fuerte-rospkg, though it still did not work until I tried the easy_inst way

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2012-06-28 09:55:04 -0500 commented answer Update Fuerte to 1.8.10 breaks rospkg

Sorry for the repeated posts. The easy_install solution seems to have worked. Is there a reason to prefer one solution over another? Thanks for the help

2012-06-28 09:37:51 -0500 commented answer Update Fuerte to 1.8.10 breaks rospkg

I can post a full backtrace if requested, but rosversion fails to load with the final error of "pkg_resources.DistributionNotFound: rospkg==1.0.4"

2012-06-28 09:36:05 -0500 commented answer Update Fuerte to 1.8.10 breaks rospkg

Could someone explain how to do this specifically? I've moved the egg files (never had a plain rospkg folder in the path listed above), fully uninstalled ros-fuerte (using apt-get, so maybe that won't reach everything), did a clean install, and roscore still errors out.

2012-06-26 09:10:32 -0500 commented question slam_gmapping MappingFromLoggedData out of dual 32-bit range

I'm having the same issue on 64bit Ubuntu 11.10 with Fuerte. Any luck solving it?

2012-06-22 03:40:33 -0500 commented answer Trouble configuring libdc1394 for Bumblebee2

Sorry, I'm not too familiar with the internals of the driver. But I'd recommend opening a separate question, as your issue is different. It's probably the best way to get your issue addressed.

2012-06-21 08:12:22 -0500 commented answer Trouble configuring libdc1394 for Bumblebee2

Not sure if this helps, but how did you change your dependencies? I had to edit my stack.xml within .../bumblebee2/camera_drivers_experimental, changing the <rosdep name="yaml-cpp" /> to <depend stack="common_rosdeps" />. I believe that was my only issue relating to yaml

2012-06-19 03:28:51 -0500 commented answer Load SDF (.model) into robot_description

Oops, I missed that you were trying to load it specifically into the robot_description param. Sorry about that.