[OpenRAVE-users] Generating IK for 6DOF humanoid appendages (prototype GFE robot) fails

[Stefan K. <ste...@gm...>]

Hi,

I tried generating ikfast IK for the arm of the prototype
GFE robot that is supplied with the 1.0 release of the DRC simulator.
The URDF file is here:

https://bitbucket.org/osrf/drcsim/src/bfb4796909f71942a8a917393c6c36dc45ce25fa/models/drc_robot/?at=drcsim_1.0.2

Confusingly, it's named model.sdf, but indeed is in URDF format.
Conversion to OpenRAVE/COLLADA gave me errors for the camhand meshes,
but otherwise succeeded. If requested, I can also attach the .dae
(it's 2.3Mb).

Generating the Transform6D IK fails for me. I used the attached scene
description and got the attached ikfast output with error "cannot
solve 6D mechanism!" in the end. I'd be grateful for any tips to get
this working (I also assume there are other people around the globe
that'd be interested ;) ).



I succeeded in generating IK for the legs, but sometimes when testing
running iktests, a assertion is hit:

[ikfastsolver.cpp:684] ik call failed for ik ikfast
ikfast.41ce8f518e437c58cb4a4b72298f906c.Transform6D.drc_left_leg
:0x67000001: ikfast exception:
/home/kohlbrecher/.openrave/kinematics.41ce8f518e437c58cb4a4b72298f906c/ikfast61.Transform6D.x86_64.40_41_42_43_44_45.cpp:1127:
polyroots4: Assertion 'rawcoeffs[0] != 0' failed

Any tips for avoiding this are also appreciated.


regards,
Stefan