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My car can not avoid the obstacles but go forward through the obstacles ，I am confused . should I change some config ？

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Another question , I input the PointCloud2 msg which is the obstacles pointcloud to the move_base . Am I right , or should I input the original pointcloud to the move_base ?

Hello ! Now I meet a new question . I had a LIDAR on my real car , and the pointclouds of obstacle were showed around the simulate car on the blank map . When I give a goal 2D navigation on the blank map , the simulate car and the real car will go to the goal . Now I hope the car can avoid the obstacles when going to the goal . The move_base will give a navigation to the goal , but it does not plan a new navigation in real time when the car meet new obstacles .

I hope the move_base can plan a navigation in real time . I am confused about it !

I have solved this problem , thank you for your advice !

Hello ! I used navigation package in my robot , but now I want to modify some code in the base_local_planner of navigation . I know that I cannot edit the source file install in /opt/ros/hydro/share , so I downloaded package here .

Before I edit the code , I ran my simulation robot in rviz and give a 2D navigation to it . I ran the $rospack find move_base to ensure that it link to the package I have download , and it shows /home/llm/chaoying/src/navigation-hydro-devel.2/move_base . But the robot went a wrong way and can not arrive the goal which is not same when I used the original move_base in /opt/ros/hydro/share . I want to know why ? Are the two package's code different ?

I ran the tf view_frames and it does broadcast . But still no point cloud displayed in rviz .

How to do this step ?

Hello ! I have a LIDAR HDL-32E on my car , and I load a car model in the rviz and display the point cloud . The "frame_id" of the LIDAR is "velodyne" and the car base's is "base_link" . Then I do these steps :

1. launch the LIDAR and publish the topic velodyne_pointclouds whose type is sensor_msg::PointCloud2 ;
2. run the tf_broadcaster , transform the frame between velodyne and base_link;
3. launch the car model and display in rviz .

But point cloud did not show out ater I add the PointCloud2 in the left window . And it informs an Error :

For frame [velodyne]:Frame [velodyne] dose not exist .

Maybe I misunderstand the tf and the relationship between reality and simulation . Can tell me what should I do ?

I have not try , but you can try to source the setup.bash file in the /opt/ros/../ in two terminal and the input roscd in each terminal .

We do not need to load a pre-created map , our car aims to run in a wide range , we do not know how to deal with the map_server .

Hello ! We team want to develop a UAV recently , and we decide to use move_base in our car's computer . But we meet many questions . Our car equipped a HDL-32E LIDAR , a GPS device . I can understand the structure of Navigation conceptually. structure But we still do not know :

1. how to use GPS data into the move_base . We plan to input a goal GPS position to the car's computer , but we do not find the interface to input .
2. Is the map_server necessary ? I think it is not useful to us ?

Could you give me some advices ? Thank you very much !

Hello , I am learning how to use OpenCV in ROS recently , now I meet a question about display the image . Here is my code :

ROS_INFO_STREAM("node1");
cv::namedWindow("test",1);
ROS_INFO_STREAM("node2");

But after I run the code , there is not window display . The terminal just print these information :

[ INFO] [1407293765.605951849]: node1
[ INFO] [1407293765.629249378]: node2

I can not understand why . Can you help me ? Thank you !

Hello ! I am using the LIDAR velodyne HDL-32E recently . The device was fixed on a car . Now I can get the data from the device using package velodyne , and I need to detect the objects and terrain on the road . So I want to know that is there any package or library can do it ? I notice some information here :http://www.ros.org/news/robots/

said:

Like many Urban Challenge vehicles, Marvin has a Velodyne HDL lidar and Applanix Position and Orientation System for Land Vehicles (POS-LV). Drivers for both of these are available in the utexas-art-ros-pkg applanix package and velodyne stack, respectively. The velodyne stack also includes libraries for detecting obstacles and drive-able terrain, as well as tools for visualizing in rviz.

Thank you ！

Yes , thank you for your share ! I think I should search it by myself first :)

Yes , the window occurred . Thank you . Maybe it should wait for several ms after imshow or namedwindow in Linux . I never met this problem in win7 with VS or QtCreator .

I ran the code in http://wiki.ros.org/cv_bridge/Tutorials/UsingCvBridgeToConvertBetweenROSImagesAndOpenCVImages , it still did not occur the window .