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2017-02-07 05:49:51 -0600 commented answer laserscan to cloud display "live"

No, in my setup,i was not able to start RVIZ until i export the ROS_IP=ipofmyremotecomputer I followed this tutorial: www.umiacs.umd.edu/~cteo/umd-erratic-ros-data/README-rvis-remote

2017-02-07 02:52:57 -0600 commented answer laserscan to cloud display "live"

Yeah, you are total right. I just use this to describe it here in the thread (i dont want to post my real adress)

2017-02-06 10:27:35 -0600 answered a question laserscan to cloud display "live"

Ok, got it: you dont have to do

export ROS_IP=KobukiIP

before starting the node.

2017-02-06 08:48:45 -0600 asked a question laserscan to cloud display "live"

Hello everybody!

I got a littlebit stucked in my progress. I manged to build a node, which converts my laserscan data "/hokuyo_laser_link" to a pointcloud2 topic "cloud". When i record data and play it back - the node works perfect and i can see my /cloud in RVIZ.

But when I start the node during a "live" test, nothing happens: thats my progress:

  1. connect via ssh to my kobuki bringup ros on the kobuki
  2. second terminal: export ROS_MASTER_URI=http://kobukiIP export ROS_IP=http:://kobukiIP rosrun rviz rviz (everthing works fine)

  3. second terminal: export ROS_MASTER_URI=http://kobukiIP export ROS_IP=http:://kobukiIP ./pointcloud2

  4. In RVIZ: Poincloud2 -> status /cloud topic ok but i cant see anything

here is my node:

#include <ros/ros.h>
#include <sensor_msgs/PointCloud2.h>
#include <pcl/point_types.h>
#include <pcl/filters/voxel_grid.h>
#include <pcl_ros/point_cloud.h>
#include <boost/foreach.hpp>
#include <pcl/io/pcd_io.h>
#include <tf/transform_listener.h>
#include <laser_geometry/laser_geometry.h>

 ros::Publisher pub;

class My_Filter {
     public:
        My_Filter();
        void scanCallback(const sensor_msgs::LaserScan::ConstPtr& scan);
     private:
        ros::NodeHandle node_;
        laser_geometry::LaserProjection projector_;
        tf::TransformListener tfListener_;

        ros::Publisher point_cloud_publisher_;
        ros::Subscriber scan_sub_;
         };

My_Filter::My_Filter(){
        scan_sub_ = node_.subscribe<sensor_msgs::LaserScan> ("/scan", 100, &My_Filter::scanCallback, this);
        point_cloud_publisher_ = node_.advertise<sensor_msgs::PointCloud2> ("/cloud", 100, false);
       tfListener_.setExtrapolationLimit(ros::Duration(0));
}

void My_Filter::scanCallback(const sensor_msgs::LaserScan::ConstPtr& scan){
    sensor_msgs::PointCloud2 cloud;
std::cout << " ich bin drin" << std::endl;
    projector_.transformLaserScanToPointCloud("/hokuyo_laser_link", *scan, cloud, tfListener_);
    point_cloud_publisher_.publish(cloud);
}



int main(int argc, char** argv)
{
    ros::init(argc, argv, "my_filter");

    My_Filter filter;

    ros::spin();

    return 0;
}

Has anyone an idea?

Thank you all in advance!

Cheers!

2017-01-28 04:29:38 -0600 received badge  Enthusiast
2017-01-23 05:30:18 -0600 asked a question Export X Y from /scan

Hello Everybody, i just want to know how to geht X and Y coordinates of the /scan Laserdata. When i play an bagfile and visualize the /scan in RVIZ it shows me XYZ (Z not needed) as well, so i think it is possible, right?

I heard something about to transform the scan data into pointcloud. But for this i need to create a publisher / subsrcriber by myself. Is there a simpler way to go?

Thank you!

Cheers

2016-12-01 05:15:42 -0600 asked a question Gmapping - pgm to svg - Autotrace

Hello everybody!

during this week i tried to generate a floorplan out of my kobuki. For this i used the gmapping algorithm which works quite well but the generated "map" was in a pgm format which is not the best format for my next steps.

Then i tried the autotrace tool which is able to convert the pgm map to an svg-map. Afterwards i wrote a small c++ parser which reads the generated svg and elimnates the furniture. (It works with an boost::geometry libary / envelope -> works at this time only with a test room in a rectangle shape but for my goal its completly fine) So the result is quiete good but my question is:

Has someone tried the autotrace conversion tool before? The tool has a lot of parameters and i want to know which are the best.

Thank you for everything and kind regards, Ben

2016-12-01 05:15:41 -0600 asked a question gmapping - pgm to svg

Hello everybody!

during this week i tried to generate a floorplan out of my kobuki. For this i used the gmapping algorithm which works quite well but the generated "map" was in a pgm format which is not the best format for my next steps.

Then i tried the autotrace tool which is able to convert the pgm map to an svg-map. Afterwards i wrote a small c++ parser which reads the generated svg and elimnates the furniture. (It works with an boost::geometry libary / envelope -> works at this time only with a test room in a rectangle shape but for my goal its completly fine) So the result is quiete good but my question is:

Has someone tried the autotrace conversion tool before? The tool has a lot of parameters and i want to know which are the best.

Thank you for everything and kind regards, Ben

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