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HKUST-Aerial-Robotics / Fast-Planner

A Robust and Efficient Trajectory Planner for Quadrotors
GNU General Public License v3.0
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Is finer control possible with lower speed? #109

Open jodusan opened 3 years ago

jodusan commented 3 years ago

I'm having trouble tuning the planner with max_vel and max_acc. If I put the values too low the planned path becomes wierd/buggy (changing often too). Is there a way to exchange speed of flight for finer flight path?

Ideally I would like it to move very slow but with more precision.

ZbyLGsc commented 3 years ago

When applying a very low speed, you should increase 'search/max_tau'

3zuli commented 3 years ago

Hello @ZbyLGsc, I have a similar problem with kino_replan. I want to use max_vel = 0.5 and max_acc = 1.0, so following your previous advice I tried setting max_tau = 1.0 and resolution_astar = .01. The planner works fine in free space, but as soon as it encounters an obstacle the trajectory becomes very chaotic, sometimes it diverges and plans a trajectory to a completely different coordinate. If I further increase max_tau to a larger value like 2.0, it can't find a trajectory unless the waypoint is within about 1m from the current position. Can you give me some advice on how can I tune the parameters better?

Edit: I think I achieved a slight improvement by setting w_time = 20, but the planner still diverges. See this video at 0:38 https://www.youtube.com/watch?v=ICieNq483v8. It seems to me that the A* planner can't find a smooth trajectory when it approaches an obstacle.