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Why is a robot's link sinking under ground when I assign to it z axis coordinate of 0 at each update I have a model plug

Why does robot behave differently written in SDF and written in URDF with SDF code included in <gazebo> tags I hav

Is it Possible To Model a Spring? Is it possible to/did anybody create a physically true model of a spring in Gazebo? Th

Is it Possible To Model a Spring? Is it possible to/did any create a physically true model of a spring in Gazebo? The ki

Gazebo usually treats a two links connected with fixed joint as one. It chooses one of the links name (it has always bee

Gazebo usually treats a two links connected with fixed joint as one. It chooses one of the links name (it has always bee

Gazebo capability of light effects simulation Say I want to see how well the visual localization on a robot would do dur

you might be looking fot the population. It's a characteristic of the world. So you put the tag directly under the <

I run a simulation into which I spawn a robot with gazebo_ros_control plugin called simply "gazebo_ros_control". This loads all successfully. Then there is a model inside the world which has gazebo_ros_control plugin. This one only starts the joint_states topic, but not the command, pid and state topic for each joint individually.

plugin of the model inside the world:

  <transmission name="tran_robotic_arm">
    <type>transmission_interface/SimpleTransmission</type>
    <joint name="arm_base_joint1">
      <hardwareInterface>hardware_interface/VelocityJointInterface</hardwareInterface>
    </joint>
    <actuator name="arm_base_motor">
      <hardwareInterface>hardware_interface/VelocityJointInterface</hardwareInterface>
      <mechanicalReduction>1</mechanicalReduction>
    </actuator>
  </transmission>

  <plugin name="testbench_control" filename="libgazebo_ros_control.so">
    <robotNamespace>/testbench</robotNamespace>
    <robotSimType>gazebo_ros_control/DefaultRobotHWSim</robotSimType>
    <legacyModeNS>true</legacyModeNS>
  </plugin>

control yaml

testbench:
  joint_state_controller:
    type: joint_state_controller/JointStateController
    publish_rate: 50  

  arm_base_joint1_controller:
    type: velocity_controllers/JointVelocityController
    joint: arm_base_joint1
    pid: {p: 10.0, i: 0.1, d: 0.01}

control launch file:

<launch>

  <!-- Load joint controller configurations from YAML file to parameter server -->
  <rosparam file="$(find testbench_control)/config/control.yaml" command="load"/>

  <!-- load the controllers -->
  <node name="controller_spawner" pkg="controller_manager" type="spawner" respawn="false"
    output="screen" ns="/testbench" args=" joint_state_controller
                                      arm_base_joint1_controller" />

  <!-- convert joint states to TF transforms for rviz, etc -->
  <node name="robot_state_publisher" pkg="robot_state_publisher" type="robot_state_publisher"
    respawn="false" output="screen">
    <remap from="/joint_states" to="/testbench/joint_states" />
  </node>

</launch>

launch file

<?xml version="1.0"?>
<launch>
    <!-- testbench ros_control launch file -->
    <!-- creates topics for joints state and joint controller -->
    <include file="$(find testbench_control)/launch/control.launch" />
</launch>

I launch this launch file after the simulation is all loaded. I want to use the /testbench/arm_base_joint1_controller/command topic to control the robotic arm joint. Is it possible? What am I doing wrong?

Turned out, that if I use this --namespace argument when launching the controller_spawner, the gazebo_ros_control plugin

Why can't I control the second robot in the simulation? I'm having problem launching and controlling two robots in one G

Why can't I control the second robot in the simulation? I'm having problem launching and controlling two robots in one G

I didn't see it, and this is almost exactly how I ended up launching the two ROS cores. Just your link to repos is wrong

The problem in this case is, that gazebo has a fixed name for the topic for it's processes. There is a topic called /gaz

Is it possible to run multiple Gazebo simulation with one ROS core and be able to interact with all the simulation (read and sent messages)?

If so, what is needed in order for this to work?

EDIT 1

I have manage to run two simulation by putting

export GAZEBO_MASTER_URI=http://localhost:11346;

before launching the second simulation and launching each simulation in different group.

<?xml version="1.0"?>
<launch>
    <!-- define arguments -->
    ...
    <!-- startup gazebo WORLD -->
   ...
   <group ns="$(arg group_name)">
        <param name="robot_description"
            command="$(find xacro)/xacro --inorder '$(find robot_gazebo)/launch/upload_robot.xacro'" />
        <node name="urdf_spawner_$(arg group_name)" pkg="gazebo_ros" type="spawn_model" respawn="false" output="screen"
            args="-urdf -model robot_$(arg group_name) -param robot_description -x $(arg robot_x) -y $(arg robot_y) -z $(arg robot_z)"/>
        <include file="$(find robot_control)/launch/$(arg group_name)_control.launch" if="$(eval control)" >
        </include>
    </group>
</launch>

I need to use the same model. To be sure I made duplicate model and named it according to the group name. I have made separate control launches for both models and set the gazebo_ros_control controllers into different namespaces.

When I launch the first simulation, it loads as normally and all the controllers loads. As soon as I run the second simulation, however, the controllers case to exist in topic list and only 3 controller topics out of 8 expected appears on rostopic list for the second robot: the 2nd_robot/joint_states and 2nd_robot/left_wheel/command and 2nd_robot/right_wheel/command (EDIT 3: This number of topics for the second robot is actually right, because I'm using the VelocityJointInterface). Only 1st_robot/joint_states remains for the first robot.

So I have two simulations running with a robot loaded, but I can't control either of the robots (EDIT 3: I can control one of the robot, the second). How do I fix this?

EDIT 2

I have even run each Gazebo simulation on different ROS core using the multimaster-fkie package, so each Gazebo simulation has different GAZEBO_MASTER_URI and ROS_MASTER_URI, yet the behavior is still the same.

The problem in this case is, that gazebo has a fixed name for the topic for it's processes. There is a topic called /gaz

Running multiple Gazebo simulations on one ROS core Is it possible to run multiple Gazebo simulation with one ROS core a

Running multiple Gazebo simulations on one ROS core Is it possible to run multiple Gazebo simulation with one ROS core a

Running multiple Gazebo simulations on one ROS core Is it possible to run multiple Gazebo simulation with one ROS core a

Running multiple Gazebo simulations on one ROS core Is it possible to run multiple Gazebo simulation with one ROS core a

Running multiple Gazebo simulations on one ROS core Is it possible to run multiple Gazebo simulation with one ROS core a

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Can I run two gazebo_ros_control plugins in one simulation? I run a simulation into which I spawn a robot with gazebo_ro

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What is the velocity assigned to the gazebo-ros-conrtol controller When I create a transmission for the wheels of my rob

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Why does tf::TransformBroadcaster crashes Gazebo simulation I'm launching a simulation with a gazebo-ros plugin, where I

Why does tf::TransformBroadcaster crashes Gazebo simulation I'm launching a simulation with a gazebo-ros plugin, where I

Why does tf::TransformBroadcaster crashes Gazebo simulation I'm launching a simulation with a gazebo-ros plugin, where I

I was using the physics::Joint::Position() function in Gazebo 9 to get the deflection of the child link from its initial position. Now I want to implement the same in Gazebo 7, but it doesn't have this function and I can't find anything in the API documentation, that looks like it does the same thing.

What can I use to get the deflection of the prismatic joint in Gazebo 7?

I was thinking about that, but the function returns an angle. How do I map this value to the prismatic joint deflection