3D cmd_vel plugin on object that ignores gravity?

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I am looking to control a robot that I can fly around without physics. Basically just an orb with sensors attached. I would like to be able to give it command velocities in 3D and have it magically traverse to a new position. What is the best way to achieve this? I have been able to turn off gravity for the world, but not the individual model. I am currently using iginiton. Any help would be appreciated.

Thanks