Change gripper during simulation without roslaunch again

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I want to perform a complex task in gazebo environment. The first part requires my UR robot to have a robotiq gripper to pick up small object, and then the second part requires a vacuum gripper to pick up large object. I need the whole process in one streamline simulation. Is it possible to change the gripper during the simulation without roslaunching a new launch file with different urdf/xacro files?