Now that we have learned about the camera plugin definition in Gazebo, we can launch the complete simulation using the following command:
$ roslaunch seven_dof_arm_gazebo seven_dof_arm_with_rgbd_world.launch
We can see the robot model with a sensor on the top of the arm, as shown here:
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Figure 2: Simulation of seven-DOF arm with Asus Xtion Pro in Gazebo
We can now work with the simulated rgb-d sensor as if it were directly plugged into our computer. So we can check whether it provides the correct image output.