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2020-02-02 08:15:09 -0500 edited question robot_localization estimates wobbling around too much when fusing GPS

robot_localization estimates wobbling around too much when fusing GPS I am trying to fuse imu, gps, and wheel odometry s

2020-01-31 09:47:32 -0500 asked a question robot_localization estimates wobbling around too much when fusing GPS

robot_localization estimates wobbling around too much when fusing GPS I am trying to fuse imu, gps, and wheel odometry s

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2019-12-17 06:56:36 -0500 edited question AMCL pose estimation is not accurate.

AMCL pose estimation is not accurate. I am using AMCL for localizing my omnidirectional-drive robot in simulation. The p

2019-12-17 05:21:08 -0500 answered a question Global planner / global map does not inflate static obstacles at all.

I fixed this issue by setting cost_scaling_factor to a smaller value (negative exponential of a small value results in

2019-12-16 08:40:32 -0500 edited question AMCL pose estimation is not accurate.

AMCL pose estimation is not accurate. I am using AMCL for localizing my omnidirectional-drive robot in simulation. The p

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2019-12-16 08:39:13 -0500 edited question AMCL pose estimation is not accurate.

AMCL pose estimation is not accurate. I am using AMCL for localizing my omnidirectional-drive robot in simulation. The p

2019-12-16 08:38:05 -0500 asked a question AMCL pose estimation is not accurate.

AMCL pose estimation is not accurate. I am using AMCL for localizing my omnidirectional-drive robot in simulation. The p

2019-12-04 11:32:49 -0500 asked a question Global planner / global map does not inflate static obstacles at all.

Global planner / global map does not inflate static obstacles at all. I am using "global_planner/GlobalPlanner" to compu

2019-12-02 07:56:43 -0500 commented question Gprof profiling output not appearing in .ros directory

I am having the same problem.

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2017-05-04 11:30:00 -0500 asked a question Flexible collision library usage

Flexible collision library usage I am new to fcl library. I am looking into the test code provided with the repository t

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2016-11-21 10:57:18 -0500 asked a question pointgrey_camera_driver for Blackfly stereo camera publishes corrupted images

I am using pointgrey_camera_driver for a stereo setup of two Pointgrey Blackfly cameras. I am launching the camera as, roslaunch pointgrey_camera_driver camera1.launch camera_serial:=16171090 and roslaunch pointgrey_camera_driver camera.launch camera_serial:=16171089 .

Everything works fine but after few minutes, the images from one of the camera is getting corrupted that two halves of the images are swapped and one half has some Bayer errors. Please see the link for an example image. https://s22.postimg.org/mqcg977ht/poi...

Could someone please suggest me how to debug the issue?

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2015-06-29 03:36:33 -0500 commented answer subscribe to image at regular time intervals

Hi Christian , in my case bandwidth is not an issue and i am using your first solution. Thanks :)

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2015-06-28 03:15:58 -0500 asked a question subscribe to image at regular time intervals

ROS indigo OpenCV

Hi, I am writing an image subscriber and i want to use this to get some 10 images and then stop and repeat this again when I call it again. For this I have written subscriber as follows,

class SubscriberImage
{
private:
    ros::NodeHandle nh;
    image_transport::Subscriber sub;
    // ...//
public:
    int perform(std::string topic)
    {
      cv::namedWindow("view");
      cv::startWindowThread();
      image_transport::ImageTransport it(nh);
      sub = it.subscribe(topic, 1, &SubscriberImage::imageCallback,this, image_transport::TransportHints("theora"));
      while(num < 10)
          ros::spinOnce();
      cv::destroyWindow("view");
      return 0;
    }

    void imageCallback(const sensor_msgs::ImageConstPtr& msg)
    {
        **/* Here I am saving 10 images to disk */** 
        try
        {
            if (num < 10 && !cv_bridge::toCvShare(msg, "bgr8")->image.empty())
            {
                cv::imshow("view", cv_bridge::toCvShare(msg, "bgr8")->image);
                cv::imwrite(name,cv_bridge::toCvShare(msg, "bgr8")->image);
            }
            else if(cv_bridge::toCvShare(msg, "bgr8")->image.empty())
            {
                ROS_INFO_STREAM("Debug: camera image is empty");
            }
            else if(num >= 10)
            {
                sub.shutdown();
            } 
        }
    }
};

I am creating an object for this class in another node and whenever I call perform(), a new subscriber object is created and in call back i save 10 images to disk. After that I am calling sub.shutdown(). Everything works as expected but one problem is I am creating a new subscriber object every time and calling shutdown() after saving 10 images. Thus creating a new subscriber object every time takes sometime. I don't this wait time.

Can this be done in a better way? Please guide me in this.

Thanks