neuronet's profile - activity

tl;dr
Running the simulation of turtlebot in Gazebo, I can't get the turtlebot to move with the turtlebot_teleop package. I launch the appropriate nodes, the right windows come up, and when I hit the q/w/e keys, nothing happens.

Long version
I did a fresh install of Ubuntu 14 and ROS Indigo today so I could get going with Turtlebot. I'm using Gazebo 2.2.3.

I am working through the turtlebot tutorial, and everything is fine up to the Stage Simulator. for the world navigation simulation, I entered:

roslaunch turtlebot_gazebo turtlebot_world.launch
roslaunch turtlebot_teleop keyboard_teleop.launch

Things generally seem to be working: when I launche turlebot_world.launch, it says:

[spawn_turtlebot_model-4] process has finished cleanly

On the other hand I do get one error during initialization:

Error [SDF.cc:788] Missing element description for [pointCloudCutoffMax]

The nodes after launch:

/bumper2pointcloud
/cmd_vel_mux
/depthimage_to_laserscan
/gazebo
/laserscan_nodelet_manager
/mobile_base_nodelet_manager
/robot_state_publisher
/rosout
/turtlebot_teleop_keyboard

Ouptut of rqt_graph:

The Gazebo screen is up, I see the simulated turtlebot in its little room. It is not stuck against a bureau or anything. I get the following output on the teleop screen when I press different keys to try to make the thing move:

I expect the little guy to be moving by default, and especially when I enter q/w/e (maybe there is some additional launch code or GO signal I'm ignorant of?). [edit: that last parenthetic remark was key] Nothing. He's just sitting there. Unlike the problem at the following link, I do not have multiple distributions of ROS (or Gazebo) on my system, so this likely isn't an issue with conflicting software versions: http://answers.ros.org/question/29983...

this is useful for folks working at the command line, but note the question explicitly asked for a way to do it programm

Sorry fixed that line, I didn't think it would be important. It's from this lab that has some packages I use: https://gi

Sorry fixed that line, I didn't think it would be important.

Tutorial for creating package: I get error that cpp_common depends on non-existent package I am setting up Kinetic on Ub

@gvdhoorn I've updated my question with the output of rosdep update.

Tutorial for creating package: I get error that cpp_common depends on non-existent package I am setting up Kinetic on Ub

Tutorial for creating package: I get error that cpp_common depends on non-existent package I am setting up Kinetic on Ub

Tutorial for creating package: I get error that cpp_common depends on non-existent package I am setting up Kinetic on Ub

Python 2.7 is not regular python anymore. This should not be the advice in 2018. Nobody is using Python 2.

it's highly recommended that you stick with the system version of python instead of downloading and installing advanc

I just spent a few hours getting this to work, and the solution turned out to be simple. First just install the qt bindi

I just spent a few hours getting this to work, and the solution turned out to be simple. First just install the qt bindi

tl;dr
I am trying to open amcl demo with:

 roslaunch chefbot_gazebo amcl_demo.launch map_file:=home/neuronet/hotel_world.yaml

And I am getting error:

Map_server could not open home/neuronet/hotel_world.yaml

Long version
I'm in indigo, ros version 1.11.20 on Ubuntu 14, and I am working through a project (chefbot) that is based on turtlebot:

http://www.instructables.com/id/Chefb...

I have run the gmapping_demo and created a map, and saved the map using

rosrun map_server map_saver -f ~/hotel_world

This has saved hotel_world.yaml and hotel_world.pgm in my home directory. Then the goal is to run the amcl demo. First (as instructed at instructables) I open the robot in gazebo, which works:

roslaunch chefbot_gazebo chefbot_hotel_world.launch

And then I launch the amcl_demo:

roslaunch chefbot_gazebo amcl_demo.launch map_file:=home/neuronet/hotel_world.yaml

It seems to start working (nodes start) but eventually I get the error that the map server could not open the yaml file:

core service [/rosout] found
process[map_server-1]: started with pid [6488]
process[amcl-2]: started with pid [6489]
process[move_base-3]: started with pid [6491]
**[ERROR] [1471437118.250759705]: Map_server could not open home/neuronet/hotel_world.yaml.**

Strangely, the. yaml file does exist in the intended directory. Here are the yaml file contents:

image: /home/neuronet/hotel_world.pgm
resolution: 0.010000 origin:
[-11.240000, -12.200000, 0.000000]
negate: 0 occupied_thresh: 0.65
free_thresh: 0.196

Further, the pgm file (image) does exist, here it is:

Note I'm working with rospy, if that matters (any technical c++ stuff will likely go over my head).

Finally, here is the file amcl_demo.launch file:

<launch>
  <!-- Map server -->
  <arg name="map_file" default="$(find chefbot_gazebo)/maps/playground.yaml"/>

  <node name="map_server" pkg="map_server" type="map_server" args="$(arg map_file)" />

  <!-- Localization -->
  <arg name="initial_pose_x" default="0.0"/>
  <arg name="initial_pose_y" default="0.0"/>
  <arg name="initial_pose_a" default="0.0"/>
  <include file="$(find chefbot_bringup)/launch/includes/amcl.launch.xml">
    <arg name="initial_pose_x" value="$(arg initial_pose_x)"/>
    <arg name="initial_pose_y" value="$(arg initial_pose_y)"/>
    <arg name="initial_pose_a" value="$(arg initial_pose_a)"/>
  </include>

  <!-- Move base -->
  <include file="$(find chefbot_bringup)/launch/includes/move_base.launch.xml"/>
</launch>

For reasons detailed here, I have been using Kinetic but need to install Indigo: http://answers.ros.org/question/24065...

As is clear there, I am a total noob to ROS. Is there a protocol for installing a new (old) distribution of ROS once you already have one? I've googled it and didn't find anything explicit. For instance, once I run roscore, which version will run? If I just install indigo and then source the bash will that become the default? Or are there collisions/conflicts I'll need to resolve such that it might be best just to uninstall Kinetic Kame?

I'm in Ubuntu 16.04.

Should mention x-posted at gazebo site: http://answers.gazebosim.org/question...

Why is the default to install an unsupported version of gazebo with an actively supported version of ROS? Gazebo is up to version 7 now! #roswtf

From gazebo answers:

There were a few issues scaling shapes and saving the world which have been fixed in newer versions of Gazebo. Since Gazebo 2 is no longer officially supported, I suggest you change to the latest long term support version, Gazebo 7.

Unfortunately, Gazebo 2.N is what comes packaged with Indigo. It is indeed possible to go renegade and install more recent versions of Gazebo:
http://gazebosim.org/tutorials/?tut=r...
Those intrepid souls who want to follow those instructions, live it up!

One workaround is to build walls out of cubes.

I'm working in ROS (Indigo, Ubuntu 14), starting gazebo 2.2.3 with

rosrun gazebo_ros gazebo

I go in and create a little corner of a room by dropping in a couple of cubes and scaling them:

I save the file as corner.world. Then later open it, and the scaling I did is gone:

I've now just got two cubes. Where did my walls go?

Note: cross-posted at: http://answers.gazebosim.org/question...