baseballmvp27's profile - activity

Hello everybody,

I just upgraded to ROS electric from diamondback and am trying to use Gazebo.

Everything worked fine with Diamondback, but now it doesn't!!!!!!!!! I don't get it. Every time I try to spawn my heightmap world, it tells me:

what(): OGRE EXCEPTION(2:InvalidParametersException): World geometry is not supported by the generic SceneManager. in SceneManager::setWorldGeometry at /tmp/buildd/ros-electric-visualization-common-1.6.2/debian/ros-electric-visualization-common/opt/ros/electric/stacks/visualization_common/ogre/build/ogre_src_v1-7-3/OgreMain/src/OgreSceneManager.cpp (line 1563)

Has anybody resolved this issue? It's driving me crazy...

I have a program which causes my robot to to go to a specific global position. How do I make this work in Gazebo?

Within Gazebo, specifically, I have a map from a .png. Basically, I want my robot to go across the board to some position while avoiding obstacles. How do I find out the "global position" (or the equivalently handled position within Gazebo) of a spot across the map to send my robot?

I believe that most people just use a separate ROS node to capture the images, and then publish them over a topic. You can then separate the hardware-specific portions of your code from the software-algorithm aspects.

I believe that this question and answer on question #57 summarize the state of the camera drivers and which should work with your specific hardware.

For additional clarification: These drivers will provide a ROS node that outputs an sensors_msgs/Image format message, streamed from the camera. You would not have to use the OpenCV getImage functions, as the driver node will be doing all of the interface with the hardware. Most video4linux cameras should work with out too much trouble.

Once you have selected a hardware driver node, you can then launch that node to interface with the Camera hardware. You would then write your own node that subscribes to the output of the hardware driver node, and read in the ROS messages that the driver node publishes (sensors_msgs/Image). You can then manipulate this image data in whatever way that you want.

This didn't work.

<lsusb> shows two buses- 001 and 002.

When I plug in both cameras, they both go on 002.

I manually went into /dev/bus/usb/ and moved the second camera from usb bus 002 to usb bus 001, but it still didn't work. same error.

when you created the package doing roscreate-pkg did you list all of the correct dependencies? If not, you can add more dependencies in the CMakeCache.txt file. This may be a reason why you are unable to compile (it has been the reason for me numerous times).

When I try to open up two video streams, I am getting an error stating that there is no space left on the device.

I know this is due to the bandwidth limitations of two cameras on one USB hub. I tried to lower the resolution of each camera, but this didn't help.

Did anybody use stereovision and successfully get two cameras to stream simultaneoulsy within ROS?

I am using usb_cam, but publishing two different topics.

thanks!

Hi Fergs,

I am having the same problem. I have two high res webcams and need access to two webcams for stereo vision. How did you get rid of this error? I know I need to lower the resolution of the webcams, but I am not sure how. Is there an easy way to do this?

-jj

unfortunately your response does not address the question.

i know what must be done, the question is how to do it. the opencv functions are not being recognized within ROS, and the question is how to use a library to do this.

For example, ROs will compile code with the OpenCV functions, but will not initialize the webcam. When linking into the CMake file, do I just add a target library and call the usb_cam library's functions? Am I able to using ros::init() and then call opencv functions, or no? it is not letting me do this now, i get runtime errors.

HELP HELP HELP!!

I posted this before, but then realized it should probably be its own question!

I have been browsing for hours! I am still confused...

I am running ROS Diamondback in Ubuntu. My codes compile, but I the webcam will not work with it!

I have a 2 Microsoft Webcams, and call opencv functions from within ROS, but the camera will not initialize. I don't understand it. I am just calling

capture = cvCaptureFromCAM(1); if (!capture) { printf("Couldn't initialize the camera for picture taking!\n"); return -1; }

and each time, the camera will not initialize!

I thought it had something to do with the fact that I didn't have a driver. However, i downloaded the usb_cam driver. I don't know how to link this in with the code to make it so that ROS can call opencv functions.

My ultimate goal is to use stereovision (2 cameras).

I can't even get one to work. What on earth do I have to do in order to get ROS to recognize my camera, and take pictures/video from inside a ROS node?!

-jj

I have been browsing for hours! I am still confused...

I am running ROS Diamondback in Ubuntu. My codes compile, but I the webcam will not work with it!

I have a 2 Microsoft Webcams, and call opencv functions from within ROS, but the camera will not initialize. I don't understand it. I am just calling

capture = cvCaptureFromCAM(1); if (!capture) { printf("Couldn't initialize the camera for picture taking!\n"); return -1;

}

and each time, the camera will not initialize!

I thought it had something to do with the fact that I didn't have a driver. However, i downloaded the usb_cam driver. I don't know how to link this in with the code to make it so that ROS can call opencv functions.

My ultimate goal is to use stereovision (2 cameras).

I can't even get one to work. What on earth do I have to do in order to get ROS to recognize my camera, and take pictures/video from inside a ROS node?!

-jj