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sbpl motion primitives

asked 2012-05-17 02:55:21 -0600

fmarques

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Hi, I'm using the sbpl_lattice planner and I have a question about how to generate my own motion primitives. My robot cannot perform foward motion arc that have a radius below 1 meter.

So I'm trying to modify the genprim_unicycle.

%1/16 theta change basemprimendpts0_c(4,:) = [4 1 1 forwardandturncostmult];

From what I can understand this is the X,y, theta displacement.

But I'm having problems in making smooth trajectories.

Does anybody already has experience in making your own motion primitives??

I've already altered the base_local_planner so it to follows the plan very accurately.

Thanks

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I'm using the standard pr2.mprim and somehow I get this error alot when I put replaning at 1 second interval ERROR: successor not found for transition

fmarques ( 2012-05-24 03:23:16 -0600 )edit

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answered 2012-05-24 21:55:33 -0600

mlphilli
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Are the motion primitives themselves not smooth or just the resulting path which is composed of the motions?

In terms of motion primitive design, you may consider reading this: M. Pivtoraiko and A. Kelly, "Generating near minimal spanning control sets for constrained motion planning in discrete state spaces"

I'd like to look into the error you're getting when replanning often....are you using ARA* or AD*?

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I'm using ARA*, normally the error occurs when I'm in constrained spaces like very narrow hallways.

fmarques ( 2012-05-24 22:04:06 -0600 )edit

The path resulting of the motion primitives is not very smooth, and I need to generate short arc but with radius longer than 1 meter. I'm going to read the Paper you suggested. Thank you very much for your help

fmarques ( 2012-05-24 22:11:03 -0600 )edit

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Asked: 2012-05-17 02:55:21 -0600

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Last updated: May 24 '12

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