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Hello everyone!

I'm a beginner in ROS and I was working around this tutorial: Coding a real time Cartesian controller with Eigen

However, the following declaration:
" typedef Eigen::Transform3d CartPose;" leads to the error: "Transform3d’ in namespace ‘Eigen’ does not name a type".

Any suggestion is very much welcome!

Yuquan

It works perfectly! I met the same issue and this is the correct solution:) I like it so much!

Later I realized it's better to skip the ros topic communication if possible and made it run.

In brief: how to public message to the topic that one sample robot_mechanism_controllers/JointVelocityController subscribes?

I launched my robot_mechanism_controllers/JointVelocityController with this yaml file:

r_shoulder_pan_joint_controller:   
 type: robot_mechanism_controllers/JointVelocityController  
 joint: r_shoulder_pan_joint  
 pid:   
   p: 10.0  
   i: 0.0  
   d: 0.0  
   i_clamp: 0.0

and I published to the topic "/r_shoulder_pan_joint_controller/command".

In my rxgraph terminal I could see that the publisher is working however the "r_shoulder_pan_joint_controller" is not subscribing. Its connection is like:

Connections:
  * topic: /rosout
   * to: /rosout
   * direction: outbound
   * transport: TCPROS
 * topic: /clock
   * to: /gazebo (<a href="http://localhost:39443/">http://localhost:39443/</a>)
   * direction: inbound
   * transport: TCPROS

In addition after the "gazebo" node received the message (that I published), it publishes it to itself instead of to "r_shoulder_pan_joint_controller" node:

topic: /r_shoulder_pan_joint_controller/command
* to: <a href="http://localhost:55720/">http://localhost:55720/</a>
* direction: inbound
* transport: TCPROS

I suppose "to: http://localhost:55720/" should be "to: /r_shoulder_pan_joint_controller"

Any hint/suggestion/discussion is very much welcome! Thanks!

Yuquan

I used this option: `launch-prefix="gdb --args" ` to launch gdb in my terminal however I got the same error: [tcsetpgrp failed in terminal_inferior: Inappropriate ioctl for device] each time I hit or continue from a break point.

Thanks for the quick reply! I'll try it.

Hi!

I'm following this tutorial and another similar solution to add an camera for my simulation. Basically what I did is adding one "Gazebo camera" block in my robot urdf.

However I could find the image topic using "rostopic" after I upload my "robot_description". So does it mean that "robot state publisher" will NOT publish the image topic automatically?

If yes, could I publish the image topic with, e.g. image transport?

Thanks!

Yuquan

this tutorial says it's possible to Roslauch nodes in gdb, but this doesn't apply to my case.

I launch the node in the following way:

  <node name="Multi_obj_qp_node" pkg="dumbo_Multi_obj_control" type="qp_multi_obj_control_node" cwd="node" respawn="false" output="screen"  launch-prefix="xterm -e gdb -d=$(find dumbo_Multi_obj_control)/ros/bin/ -e=qp_multi_obj_control_node" >
<rosparam command="load" file="$(find dumbo_Multi_obj_control)/config/Multi_obj_lp.yaml"/>

</node>

But I got the following error:

Exception AttributeError: AttributeError("'_DummyThread' object has no attribute '_Thread__block'",) in <module 'threading' from '/usr/lib/python2.7/threading.pyc'> ignored

Roslaunch got a 'No such file or directory' error while attempting to run:

`xterm -e gdb -d=/home/yuquan/myrepo/dam/ros/dumbo_apps/dumbo_Multi_obj_control/ros/bin/ -e=qp_multi_obj_control_node /home/yuquan/myrepo/dam/ros/dumbo_apps/dumbo_Multi_obj_control/ros/bin/qp_multi_obj_control_node __name:=Multi_obj_qp_node __log:=/home/yuquan/.ros/log/fa2d2a5c-2381-11e2-b6dc-0022150df8c3/Multi_obj_qp_node-5.log

Please make sure that all the executables in this command exist and have executable permission. This is often caused by a bad launch-prefix.

One of my friends says gdb works with a single node just like a usual executable. But in my case I need to launch yaml together. Could any one give me some suggestions?

Yes, It works! Great!

Hi, another question is would the "state_publisher" publish topic "/ptz/image_raw" automatically or do we need to publish topic "/ptz/image_raw" ourselves with, for example, image_transport package?