Joelac0193's profile - activity

I am trying to follow this tutorial: http://library.isr.ist.utl.pt/docs/ro...

I have changed all the parameters to match the names of my robot's motors.

This is my .yaml file:

• nxt_robot:
  • type: motor name: Motor_B port: PORT_B desired_frequency: 10.0
  • type: motor name: Motor_C port: PORT_C desired_frequency: 10.0
  • type: motor name: Motor_A port: PORT_A desired_frequency: 10.0
  • type: touch frame_id: r_touch_link name: touch_sensor port: PORT_3 desired_frequency: 10.0
  • type: ultrasonic frame_id: r_ultrasonic_link name: ultrasonic_sensor port: PORT_2 spread_angle: 0.5 min_range: 0.01 max_range: 2.55 desired_frequency: 10.0
  • type: color frame_id: l_color_link name: color_sensor port: PORT_1 desired_frequency: 5.0

I don't know why it's not working. Any help will be greatly appreciated, as I am new to ROS and don't know too much.

Hello, I have Ubuntu 10.04 and ROS Electric, and I am trying to follow this tutorial: http://wiki.ros.org/nxt_lxf2urdf/Tuto...

When I run rviz it opens up but the robot that was created in the urdf file does not show up, only a black screen. I was originally getting "segmentation fault" which I solved by using this command: export OGRE_RTT_MODE=Copy

Any ideas as to why I am encountering this problem and how to solve it?

It was working a few months ago and I have not touched ROS since. I am using ROS electric and Ubuntu 10.04, and I am following the tutorials on how to make ROS work with Legos NXT. When I type roslaunch robot.launch I get the error:

respawning...
[nxt_ros-2] restarting process
process[nxt_ros-2]: started with pid [6573]
Traceback (most recent call last):
  File "/opt/ros/electric/stacks/nxt/nxt_ros/scripts/nxt_ros.py", line 49, in <module>
    from PyKDL import Rotation
ImportError: No module named sip
[nxt_ros-2] process has died [pid 6573, exit code 1].
log files: /home/joel/.ros/log/19cd638e-84de-11e5-a689-0026b9c3b537/nxt_ros-2*.log

I do not now what is causing this problem and am not too knowledgeable with ROS or Linux. Any help will be greatly appreciated, thank you.

There it goes

enter code hereI am using ROS Electric, and when I add the NXTULTRASONICDISPLAY and NXTCOLORDISPLAY in Rviz, the terminal outputs:

[ WARN] [1428430767.098592506]: Message from [/nxt_ros] has a non-fully-qualified frame_id [r_ultrasonic_link]. Resolved locally to [/r_ultrasonic_link].  This is will likely not work in multi-robot systems.  This message will only print once.
[ WARN] [1428430767.099069103]: Message from [/nxt_ros] has a non-fully-qualified frame_id [l_intensity_link]. Resolved locally to [/l_intensity_link].  This is will likely not work in multi-robot systems.  This message will only print once.
[ WARN] [1428430782.123835606]: MessageFilter [target=/ref_0_link ]: Dropped 100.00% of messages so far. Please turn the [ros.nxt_rviz_plugin.message_notifier] rosconsole logger to DEBUG for more information.

I have no idea what to do. I'm fairly new to ROS so please be specific and explicit when giving instructions. Thanks!

Nevermind I got it. I input the command sudo -s and it worked. Thanks

Well whenever I do anything in the terminal I always input this command: sudo -i

I am on Ubuntu 10.04 and I have ROS Electric installed. I am following these instructions and I am on Step 3 (Generating the URDF): http://wiki.ros.org/nxt_lxf2urdf/Tuto...

When I input the command rosrun nxt_lxf2urdf lxf2urdf.py robot.lxf robot.ldr >robot.urdf I get:

[rospack] WARNING: cannot create rospack cache directory: Permission denied
[rospack] WARNING: cannot create rospack cache directory: Permission denied
[rospack] Unable to create temporary cache file /root/.ros/.rospack_cache.cSxwgs: Permission denied

What to do? I am fairly new to Ubuntu and ROS.

Thanks for pointing that out! Turns out the file was somewhere else. Thanks!

So I've created two files: robot.launch and robot.yaml. Robot.launch contains this:

Robot.yaml contains this:

nxt_robot: - type: touch frame_id: touch_frame name: my_touch_sensor port: PORT_1 desired_frequency: 20.0

When I use roslaunch robot.launch I get:

root@joel:~/learning_nxt# roslaunch robot.launch ... logging to /root/.ros/log/ea9ca04a-da59-11e4-aa30-080027df9655/roslaunch-joel-21391.log Checking log directory for disk usage. This may take awhile. Press Ctrl-C to interrupt Done checking log file disk usage. Usage is <1GB.

error loading tag: file does not exist [/opt/ros/electric/stacks/nxt/learning_nxt/robot.yaml] XML is root@joel:~/learning_nxt#

Then when I run roslaunch robot.yaml I get:

root@joel:~/learning_nxt# roslaunch robot.yaml ... logging to /root/.ros/log/158aef32-da5a-11e4-aa30-080027df9655/roslaunch-joel-21400.log Checking log directory for disk usage. This may take awhile. Press Ctrl-C to interrupt Done checking log file disk usage. Usage is <1GB.

Invalid roslaunch XML syntax: syntax error: line 1, column 0 root@joel:~/learning_nxt#

What is wrong here? I input the contents of the file robot.yaml into http://yaml-online-parser.appspot.com/ and it says that there is nothing wrong with the text.

By the way, I am following these instrucutons: http://wiki.ros.org/nxt_ros/Tutorials... - steps (3.2), (3.3) and (3.4)