devesh's profile - activity

Hi jsergeant, unfortunately I'm out of touch with ROS and don't use it anymore. I remember it was a tedious chase to fix errors for compilation but don't even remember what all I did to get it to work.

http://stackoverflow.com/a/21432657/7...

The above link helped me solve it.

I got the same error in the drone_stateestimation node. But, it is a slightly different situation for me. I get this error when I run a bag file recorded from a different machine.

It turned out that the Navdata message type had a different checksum in my ardrone autonomy driver and the other machines autonomy driver. The checksum is made purely from the file contents. So, I changed my msg/Navdata.msg file to look like the other one. Recompiling and running the bag file work there after.

I am not able to make hector_quadrotor_demo as mention here http://wiki.ros.org/hector_quadrotor/Tutorials/Quadrotor%20outdoor%20flight%20demo

I am not sure what rosinstall command to run. And then, from hydro onwards, gazebo is not included as part of ros but needs to be installed separately. The package that is used is gazebo_ros instead of gazebo.

I am not able to proceed much further because all modifications I try end up with lots of build dependencies which I seem not able to solve.

Looking into some sample .world files, I can see that interval_sim value can be set in milliseconds. It seems to be working fine for 100 ms. But when I make it 0.1 ms, it doesn't seem to be running that fast. I am publishing strings via ros topics (by changing code in stageros.cpp) to test how fast it can publish. Either ros publishing or stageros cannot seem to cross the millisec boundary.

Any suggestions, experiences, fixes regarding running stageros simulation (without gui) in the microseconds range?

As gustavo suggested, I modified src/stageros.cpp. The boolean 'stall' is set iff there is a collision at the instant. Stalled() function returns this value and can be called to check.

Other details regarding the solution

But after modifying, 'rosmake stage' does not work for some reason (just like this thread http://answers.ros.org/question/87666/no-executable-in-bin-with-rosmake-on-groovy/)

So, after modifying the permissions of the stage stack folder I ran 'make'. After downloading the md5sum tarball into the build folder, it compiled most of the code. But then, it gave out the error "undefined reference to Fl::wait(double)".

Turns out, it is a problem with gcc and ordering of flags. So, as suggested in http://player-stage-gazebo.10965.n7.nabble.com/Stage-install-error-td6455.html, I edited CMakeLists.txt towards the bottom into (I just added the 3rd line)

rosbuild_add_compile_flags(bin/stageros ${STAGE_CFLAGS_OTHERS})
target_link_libraries(bin/stageros ${STAGE_LIBRARIES})
target_link_libraries(bin/stageros fltk fltk_gl fltk_images)
rosbuild_add_link_flags(bin/stageros ${STAGE_LDFLAGS_OTHERS})

I am in an exactly similar situation. RL controller with stageros for simulation.

Thanks. All this worked for me. There were slight hiccups though. 1) It was line 121 for me, instead of line 122. 2) I was making the dumb mistake of not removing- '#include "joy/Joy.h"' line 3) Third dumb mistake was including "sensor_msg/Joy" instead of "sensor_msg/Joy.h" 4) KevinNickels comment.

There is a well documented page which gives information about all the apis, etc. http://www.ros.org/wiki/geometry/Rota...

Hope this helps others who come across this question later on.

In case someone comes across this question and wants an answer, check this out - http://answers.ros.org/question/12116/calling-gazebo-service-set_model_state-in-c-code/

In the simple case when quadrotor is on ground,I've realized that the yaw value in rviz gives me the orientation of the quadrotor rotated about the z-axis of the world(and its own z-axis).Similarly,the quaternion I get is x = 0,y = 0,z = -sin(theta/2),w = -cos(theta/2). I don't understand why though

Hi, I am currently using the gazebo tum_simulator for ardrone. I am looking at the simulated environment in Rviz. I have a python subscriber/publisher code where I am getting the Pose(world coordinates plus quaternion orientation) of the quadrotor. I also know the destination's world co-ordinates.

My main aim - turn the quadrotor towards the destination and then head in a straight line towards it. How can I do this?

Other specific questions I have are What is base_link? The base_link for the drone is seen as 0 for all fields(as seen in rviz)

How do I interpret the pose quaternion I get for the drone? I read a little bit about quaternion and I know what it is but I can't figure out the reference axis and how to interpret it in this case.

Thanks, joq. I did consider rqt too but later stuck to pure rviz. But, the main thing I want here is a way for coding using rviz without any documentation.

Finally got something working using this link below. http://ros.org/rosdoclite/groovy/api/rviz_python_tutorial/html/

To create an image panel, all I needed to do was write a config file(which included a image display panel and the topic to subscribe from) and then load that config file.

Instead of manually creating the config file, I open rviz and then created a Display Panel in that and then added image to the Display and then set the topic in the properties for the image. Then, I saved these configs in from the File menu and am currently using it.

I have been trying to make a gui using rviz in python. The widgets I am creating have an rviz VisualizationFrame in them. There are gui elements there but there is no documentation anywhere that I could find, especially for the apis to these elements.

Anyone knows anyway I could solve this problem, apart from the many dir() calls I am currently making at each step to know all the callable functions?

I am not sure if this should be another question or can be included here, but is there any documentation for writing the config file for rviz(to load from)?

Sorry jj56. But I haven't been able to use that link because I am finding it hard. I believe I am much more of a noob than someone who could follow that tutorial. I still don't know how to add an image display panel.

Hi, I am a total ROS/gazebo noob. I recently installed groovy on ubuntu 12.10 and I am running the TUM's gazebo simulator for a quadrotor.

My question - There is an image topic being published by the simulator(which is the 2D image of the world that the quadrotor sees using its camera). I can view this image in rviz or using image_view package.

How do I create a gui window where I can display this image and when I click at a location in the image, I get the mouse click event(location of the click within the image window)?

I would appreciate if the solution is a bit more detailed or guiding as I am a total noob to ROS itself.(the solution need not be related to rviz)