Connect an object to two robots in separate namespaces?

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Hi,

I am trying to simulate a hanging payload attached to multiple separate drones. I currently spawn two drones in separate namespaces, each being controlled independently. I have created a URDF for the payload which is attached to a single drone, is it possible to extend this link to another drone in a separate namespace? How would you recommend achieving this?

I am using ROS Kinetic with RotorS simulator on Ubuntu 16.04.

Thanks!