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2013-08-11 12:59:07 -0500 asked a question Installing Gazebo 1.9 on ROS Groovy

Hello,

Today I wanted to update my installed gazebo (version 1.8.6) to 1.9. First I uninstalled the local installed version. Then I installed the Pre-compiled binaries on Ubuntu 12.04 following these steps: http://gazebosim.org/wiki/1.9/install

No I want to install the gazeborospkgs too (http://gazebosim.org/wiki/Tutorials/1.9/Installinggazeboros_Packages) but there occurred some issues:

1) When I call after the Installation rosdep update the following output is printed:

reading in sources list data from /etc/ros/rosdep/sources.list.d
Hit https://github.com/ros/rosdistro/raw/master/rosdep/osx-homebrew.yaml
Hit https://github.com/ros/rosdistro/raw/master/rosdep/gentoo.yaml
Hit https://github.com/ros/rosdistro/raw/master/rosdep/base.yaml
Hit https://github.com/ros/rosdistro/raw/master/rosdep/python.yaml
Hit https://github.com/ros/rosdistro/raw/master/rosdep/ruby.yaml
Hit https://github.com/ros/rosdistro/raw/master/releases/fuerte.yaml
Ignore legacy gbpdistro "groovy"
Ignore legacy gbpdistro "hydro"
Query rosdistro index https://raw.github.com/ros/rosdistro/master/index.yaml
Add distro "groovy"
Add distro "hydro"
updated cache in /home/alex/.ros/rosdep/sources.cache

...and rosdep check --from-paths . --ignore-src --rosdistro groovy:

All system dependencies have been satisified
ERROR[effort_controllers]: resource not found [control_msgs]

What does this error mean?!

2) When I call now catkin_make in may workspace, the following errors occurred:

CMake Error at /opt/ros/groovy/share/catkin/cmake/catkinConfig.cmake:72 (find_package):
  Could not find a configuration file for package control_msgs.

  Set control_msgs_DIR to the directory containing a CMake configuration file
  for control_msgs.  The file will have one of the following names:

    control_msgsConfig.cmake
    control_msgs-config.cmake

Call Stack (most recent call first):
  ros_controllers/effort_controllers/CMakeLists.txt:19 (find_package)

and

-- Configuring incomplete, errors occurred!
make: *** [cmake_check_build_system] Error 1
Invoking "make cmake_check_build_system" failed

So what can I do to remake Gazebo working with ROS Groovy?! Do I have to update to ROS Hydro?!

Thanks for your help :)

2013-07-24 12:54:58 -0500 commented question How to simulate a Stewart Platform with Gazebo and ROS?

After some other test I would say that the problem is that gazebo does not detect a collision. I found some other questions about this topic but no solution...<selfCollide>true</selfCollide> is set in all links. Do I have to do something more?

2013-07-24 11:57:43 -0500 commented answer How to simulate a Stewart Platform with Gazebo and ROS?

My program increase/decrease in a loop every second the z-pos of the box since a limit I set. So the box change his position slowly which works when I don't connect it with the platform over my connection explained above (over a joint it works). "the platform moves randomly in any direction and the actuator breaks" mean that if I connect the platform without a joint it falls out of the connection even if it couldn't and the box which pos I change begins to move really fast between the limits.

2013-07-24 11:43:55 -0500 commented answer How to simulate a Stewart Platform with Gazebo and ROS?

Thanks a lot :) I tried out the two tutorials (it looks like both have nearly the same code?!) and after some changes (had to rename common.h and physics.h to common.hh and physics.hh and also the function *.GetAsRadian() to *.Radian()) it compiled. But when I started gazebo I got this message: Error [Plugin.hh:126] Failed to load plugin libpid_joints.so: cannot open shared object file: No such file or directory - even if I can find the file in my build-directory. Do you have an idea?

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2013-07-21 13:12:30 -0500 asked a question How to simulate a Stewart Platform with Gazebo and ROS?

Hi :)

For an own project I want to move a platform with a pneumatic system (like the Stewart platform and for this I need a simulation with Gazebo. I'm really a beginner in using Gazebo and ROS and so I started with some tests (and tutorials) to learn how to use both systems. To begin with a "simple urdf-file" I created a table (1 platform with 4 legs) where I want to change the size of the legs. My aim is that Gazebo simulates the position of the platform when I change the size of each leg. But now I have some problems where I don't know how to solve them - maybe you can help me :)

I'm using the standalone version of Gazebo with Groovy on Ubuntu 12.04 32-Bit.

1) Unfortunately the tutorials ends before the description of how to manipulate the robot with controllers (here) and in addition I can't find a controller which simulates a pneumatic actuator. So I decided to create two boxes and to change the position of the inner box with a c++-program - this works for the moment very nice :) The problem is that I have to switch of the gravity for the inner box to avoid that it falls down - do you have a better idea to solve this problem?

  <!-- Link 1 (outer box)-->
  <joint name="Pn1_joint1" type="fixed">
    <origin xyz="0 0 0"/>
    <parent link="world"/>
    <child link="Pn1_link1"/>
  </joint>

  <link name="Pn1_link1">
    <collision>
    <origin xyz="0 0 0.05" rpy="0 0 0"/>
      <geometry>
    <box size="${widthPneumatic} ${widthPneumatic} 0.1"/>
      </geometry>
    </collision>
    <visual>
      <origin xyz="0 0 ${heightPneumatic/2}" rpy="0 0 0"/>
      <geometry>
    <box size="${widthPneumatic} ${widthPneumatic} ${heightPneumatic}"/>
      </geometry>
      <material name="orange"/> 
    </visual>
    <inertial> 
      <origin xyz="0 0 ${heightPneumatic/2}" rpy="0 0 0"/> 
      <mass value="1"/>            
      <inertia
      ixx="1.0" ixy="0.0" ixz="0.0"
      iyy="1.0" iyz="0.0"
      izz="1.0"/>
    </inertial>
  </link>

  <gazebo reference="Pn1_link1">
    <material>Gazebo/Orange</material>
  </gazebo>          

  <!-- Link 2 (inner box) -->
  <joint name="Pn1_joint2" type="prismatic">
    <origin xyz="0 0 0"/>
    <parent link="Pn1_link1"/>
    <child link="Pn1_link2"/>
    <axis xyz="0 0 1"/>
    <dynamics damping="100"/>
    <limit lower="0" upper="${heightPneumatic}" effort="0.00001" velocity="0.00001"/>
  </joint>

  <link name="Pn1_link2">
    <collision>
      <origin xyz="0 0 ${heightPneumatic/2}" rpy="0 0 0"/>
      <geometry>
    <box size="${widthPneumatic-diffInOut} ${widthPneumatic-diffInOut} ${heightPneumatic+diffInOut}"/>
      </geometry>
    </collision>
    <visual>
      <origin xyz="0 0 ${heightPneumatic/2}" rpy="0 0 0"/>
      <geometry>
    <box size="${widthPneumatic-diffInOut} ${widthPneumatic-diffInOut} ${heightPneumatic+diffInOut}"/>
      </geometry>
      <material name="orange"/>
    </visual>
    <inertial>
      <origin xyz="0 0 ${heightPneumatic/2}" rpy="0 0 0"/>
      <mass value="1"/>
      <inertia
      ixx="1.0" ixy="0.0" ixz="0.0"
      iyy="1.0" iyz="0.0"
      izz="1.0"/>
    </inertial>
  </link>

  <gazebo reference="Pn1_link2">
    <material>Gazebo/Orange</material>
    <turnGravityOff>true</turnGravityOff>
    <mu1>100</mu1>
    <mu2>100</mu2>
    <selfCollide>true</selfCollide>
  </gazebo>

2) So I added a second one to the world and wanted to connect these two actuators with the platform. There the tree structure of the urdf-file causes ... (more)