Local planner current research issues

Hello @LorenzMeier, @baumanta, @nicovanduijn. Hope you are having a great day.

I am a research student at IIT kgp, India. I have worked a bit with drones. I see that github page tells “developers are currently focused on local_planner” in collision avoidance.

I would love to hear what current research challenges/areas on local planner are of importance. I would like to pick an area to work upon and finally test/compare with existing techniques. Can you people suggest me some topic/resources/research articles that can enlighten me in this field. I have some knowledge about what local planner has been implemented in PX4 stack but want to know the current scenario.