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It's hard to tell from just the one Gazebo view, but I think your urdf has spawned successfully in Gazebo (i.e. it's not actually broken).

The arm's links are jumbled up because the joints are not being actuated.

RViz is a visualizer, so you can "move" an arm in RViz just by broadcasting ideal joint states. Gazebo is a simulator, so you have to somehow inject joint forces into the simulated world. Otherwise you should expect limp arm behavior - similar to the real world.

You have to write/use a Gazebo Plugin that applies efforts to the joints or use en existing package like ros_control.

Some quick ways to check this:

• Spawn URDF in Gazebo off the ground (e.g. -x 0 -y 0 -z 6).
• As @ARB suggests, turn gravity off for your arm.
• View -> Joints
• Start simulation Paused and manually advance simulation in small time steps to see if arm is collapsing normally under effects of gravity or is "exploding" due to some defect in model (inertial matrices looked pretty normal so unlikely).

It's hard to tell from just the one Gazebo view, but I think your urdf has spawned successfully in Gazebo (i.e. it's not actually broken).

The arm's links are jumbled up because the joints are not being actuated.

Edit: Based on OP update, it seems urdf in Gazebo has no joints.

RViz is a visualizer, so you can "move" an arm in RViz just by broadcasting ideal joint states. Gazebo is a simulator, so you have to somehow inject joint forces into the simulated world. Otherwise you should expect limp arm behavior - similar to the real world.

You have to write/use a Gazebo Plugin that applies efforts to the joints or use en existing package like ros_control.

Some quick ways to check this:

• Spawn URDF in Gazebo off the ground (e.g. -x 0 -y 0 -z 6).
• As @ARB suggests, turn gravity off for your arm.
• View -> Joints
• Start simulation Paused and manually advance simulation in small time steps to see if arm is collapsing normally under effects of gravity or is "exploding" due to some defect in model (inertial matrices looked pretty normal so unlikely).

It's hard to tell from just the one Gazebo view, but I think your urdf has spawned successfully in Gazebo (i.e. it's not actually broken).

The arm's links are jumbled up because the joints are not being actuated.

Edit: Based on OP update, it seems urdf in Gazebo has no joints.all the joints in the same location...

RViz is a visualizer, so you can "move" an arm in RViz just by broadcasting ideal joint states. Gazebo is a simulator, so you have to somehow inject joint forces into the simulated world. Otherwise you should expect limp arm behavior - similar to the real world.

You have to write/use a Gazebo Plugin that applies efforts to the joints or use en existing package like ros_control.

Some quick ways to check this:

• Spawn URDF in Gazebo off the ground (e.g. -x 0 -y 0 -z 6).
• As @ARB suggests, turn gravity off for your arm.
• View -> Joints
• Start simulation Paused and manually advance simulation in small time steps to see if arm is collapsing normally under effects of gravity or is "exploding" due to some defect in model (inertial matrices looked pretty normal so unlikely).

It's hard to tell from just the one Gazebo view, but I think your urdf has spawned successfully in Gazebo (i.e. it's not actually broken).

The arm's links are jumbled up because the joints are not being actuated.

Edit: Based on OP update, it seems urdf in Gazebo has all the joints in the same location...

RViz is a visualizer, so you can "move" an arm in RViz just by broadcasting ideal joint states. Gazebo is a simulator, so you have to somehow inject joint forces into the simulated world. Otherwise you should expect limp arm behavior - similar to the real world.

You have to write/use a Gazebo Plugin that applies efforts to the joints or use en existing package like ros_control.

Some quick ways to check this:

• Spawn URDF in Gazebo off the ground (e.g. -x 0 -y 0 -z 6).
• As @ARB suggests, turn gravity off for your arm.
• View -> Joints
• Start simulation Paused and manually advance simulation in small time steps to see if arm is collapsing normally under effects of gravity or is "exploding" due to some defect in model (inertial matrices looked pretty normal so unlikely).
• Use the joint_state_publisher (with GUI) and robot_state_publisher in RViz to verify joints are as expected.

It's hard to tell from just the one Gazebo view, but I think your urdf has spawned successfully in Gazebo (i.e. it's not actually broken).

The arm's links are jumbled up because the joints are not being actuated.

Edit: Based on OP update, it seems urdf in Gazebo has all the joints in the same location...

RViz is a visualizer, so you can "move" an arm in RViz just by broadcasting ideal joint states. Gazebo is a simulator, so you have to somehow inject joint forces into the simulated world. Otherwise you should expect limp arm behavior - similar to the real world.

You have to write/use a Gazebo Plugin that applies efforts to the joints or use en existing package like ros_control.

Some quick ways to check this:

• Spawn URDF in Gazebo off the ground (e.g. -x 0 -y 0 -z 6).

• <!-- Spawn a urdf in Gazebo, taking the description from the parameter server -->
  <node name="spawn_urdf" pkg="gazebo_ros" type="spawn_model"
      args="-param robot_description -urdf -model robot -x 0 -y 0 -z 6" />
  

• As @ARB suggests, turn gravity off for your arm.

• View -> Joints
• Start simulation Paused and manually advance simulation in small time steps to see if arm is collapsing normally under effects of gravity or is "exploding" due to some defect in model (inertial matrices looked pretty normal so unlikely).
• Use the joint_state_publisher (with GUI) and robot_state_publisher in RViz to verify joints are as expected.

It's hard to tell from just the one The URDF is spawning successfully in Gazebo view, but I think your urdf has spawned successfully in Gazebo (i.e. it's not actually broken).

The arm's links are jumbled up because the joints are not being actuated.

The robot is then "exploding" - after which all the links are collected at the origin.

Edit: Based Update: At least one of the links in the URDF has an incorrect Inertial matrices (probably way too small)

To fix:

1) Change all your inertia tags to:

<inertia ixx="0.0001" ixy="0.000"  ixz="0.000"  
         iyy="0.0001" iyz="0.000"
         izz="0.0001"
/>

(You can go back and fix these later. Either using geometric approximations or something like MeshLab

Note: In Gazebo, View -> Inertia will give you a ballpark idea of the inertial matrices. To understand what the purple boxes actually mean check out http://gazebosim.org/tutorials?tut=inertia#CheckinginGazebo)

2) If model still explodes, disable self-collision for all links:

<gazebo reference="link_10">
  <selfCollide>False</selfCollide>
</gazebo>

You can re-enable self-collisions selectively. Links that are penetrating on OP update, it seems urdf in spawn can cause the model to "explode"

3) (Optional) I always enable implicitSpringDamping for better stability simulating joint damping:

<gazebo reference="joint_9">
  <implicitSpringDamper>True</implicitSpringDamper>
</gazebo>

You should be able to spawn your model into Gazebo has all the joints in the same location...like so:

Note: Gazebo Answers (http://answers.gazebosim.org/questions/) is usually where I go with these types of Gazebo-focused questions if you end up running into any other snags.

Old: Maybe useful info but not the correct answer to OP's problem

RViz is a visualizer, so you can "move" an arm in RViz just by broadcasting ideal joint states. Gazebo is a simulator, so you have to somehow inject joint forces into the simulated world. Otherwise you should expect limp arm behavior - similar to the real world.

You have to write/use a Gazebo Plugin that applies efforts to the joints or use en existing package like ros_control.

Some quick ways to check this:debugging:

• Spawn URDF in Gazebo off the ground (e.g. -x 0 -y 0 -z 6).

  <!-- Spawn a urdf in Gazebo, taking the description from the parameter server -->
  <node name="spawn_urdf" pkg="gazebo_ros" type="spawn_model"
      args="-param robot_description -urdf -model robot -x 0 -y 0 -z 6" />
  

• As @ARB suggests, turn gravity off for your arm.

• View -> Joints
• View -> Inertia
• Start simulation Paused and manually advance simulation in small time steps to see if arm is collapsing normally under effects of gravity or is "exploding" due to some defect in model (inertial matrices looked pretty normal so unlikely).
• Use the joint_state_publisher (with GUI) and robot_state_publisher in RViz to verify joints are as expected.