How to identify the leader robot?

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I have three turtle bots, one of which is a leader and the remaining two are followers. I used the tf package to set up the leader follower relationship. For example, I collected the distance and angle information between leader and follower1 or follower1 and follower2 over tf and put them into a fuzzy logic algorithm. The system works as it is. Then I want to put this system in an environment with obstacles and send the leader to a target point. I actually wanted to use laser knowledge in the leader-follower approach, but in an environment with obstacles, how will the followers understand the difference between the leader and the obstacles?