Why rmf send follow_new_path every 30 seconds even if the robot has reached the destination

[ghost]

Hi,

My test scenario is using go_to_place to request the robot to move to the specified destination.
When the robot had reached the destination and callback function path_finished_callback had been invoked, I found rmf still continued to call follow_new_path to the robot at the frequency of once per 30 seconds.
In each such kind of follow_new_path request, there are 2 waypoints. And the two waypoints are the same point. It looks as if rmf commands the robot to stand still.
My question is why rmf will send these follow_new_path periodically?

Thanks
Stella

[ghost]

I will move this discussion to rmf category