Question about urdf file and gazebo/msgs

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Hi,

I'm working on a robot arm, i already created a urdf and controller.yaml file to control my robot in gazebo with trajectory_msgs.

Now, i would like to add a target in gazebo, behind my robot and make it move in space as a function of x, y, z. The goal is that the arm reach the target using inverse kinematic.

So i would like to know what is the best way to do this :

• Should I create another urdf and controller (yaml) file for my target or i can added the model of the target in my robot_arm.urdf?
• To lead my target in space(x,y,z), i would like to use "geometry_msgs/Point.msg", is this the right method?

If you know some tutorials to do this i want them.

Thank you for your answers.