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The sbpl_lattice_planner is extending path unnecessarily

Hi, I'm using this fork with its sbpl package, for indigo. And created motion primitive file with genmprim_unicycle.m ( for forward, backward, turn-in-place, forward-turn-arcs) on Matlab.

At the beginning, It computes path very well. But When the robot is near to end, planner is updating path with absurd one. And struggling with a bit left / right movements, here is image: Struggling

How can I solve this problem? And Here is its parameters:

SBPLLatticePlanner:
  planner_type: "ARAPlanner"
  allocated_time: 10.0
  initial_epsilon: 2.83 
  environment_type: "XYThetaLattice"
  forward_search: false
  primitive_filename: "" # Setting in launch file
  force_scratch_limit: 500 
  nominalvel_mpersecs: 0.4
  timetoturn45degsinplace_secs: 0.6

Thank You.

Asked by Orhan on 2016-02-19 10:24:16 UTC

Comments

And Footprint Rectangle is coming late.

Asked by Orhan on 2016-02-19 10:34:41 UTC

It looks like your robot is starting in one orientation, and ending in the opposite orientation somehow. Does it track the path well?

Asked by ahendrix on 2016-02-20 14:16:04 UTC

No, dwa_local_planner follows path at the beginning only. I'll increase its path_distance_bias. I'll write after this, I'm on mobile now.

Asked by Orhan on 2016-02-20 14:45:07 UTC

But global plan is changing fast.

Asked by Orhan on 2016-02-20 14:45:59 UTC

dwa_local_planner cannot follow the backing maneuvers that SBPL generates; it will get confused by them and command the robot to turn or move in the wrong direction. I strong suggest you use a different local planner.

Asked by ahendrix on 2016-02-20 14:54:48 UTC

I can configure dwa_local_planner for following path at the beginning, here is why I'm using dwa_local_planner.

Asked by Orhan on 2016-02-20 15:13:16 UTC

And Thank you sir. What's your best suggestion for global and local planner? Here is my other question for my robot's motion.

Asked by Orhan on 2016-02-20 15:25:17 UTC

I'm not aware of any good local planners for this. This may be a good starting point, but it needs a lot of work.

Asked by ahendrix on 2016-02-21 00:50:35 UTC

Answers