I am working on a custom 5 DOF arm(image at the bottom). I have generated the URDF, the MoveIt configs etc for it.
I want to have the basic IK, planning and collision detection features of MoveIt. Before programming my application, I tried running the simple planning in RViz, using the interactive marker etc. Now, since it is a 5 dof system, I had to enable "Allow Approximate IK solutions", for it to let me use the interactive markers.
It was using OMPL by default. I tried planning for some random-valid goal states. The problem is that the planning success rate was very very low. 4 out of 5 times the planning failed. I also tried changing the planners from the dropdowns, but none of them were consistent in planning succesfully, all of them were failing quite frequently.
After looking up this problem [here on Ros-Answers](http://answers.ros.org/question/10407/inverse-kinematics-solver/) and many other places, we found that IKFast would be what we should use, as it works reliably for 5 dof systems.
After installing openrave and ikfast via source, we ran the commands to generate a IKfast cpp file(using [this tutorial](http://wiki.ros.org/Industrial/Tutorials/Create_a_Fast_IK_Solution)) for our robot model. We tried the TranslationDirection5D ik type. Now here we are getting a `tuple index out of range error` which is something that others have faced before and have not been able to solve. See [this](http://openrave-users-list.185357.n3.nabble.com/Struggling-to-get-ikfast-to-work-td4027761.html) and [this](http://openrave-users-list.185357.n3.nabble.com/IndexError-tuple-index-out-of-range-td4026855.html). Basically, we've now hit a wall trying to get the IK on my 5 dof robot to work properly. Openrave is not even able to generate an Ikfast cpp.
Here'ss the exact error i get when i try to generate an ikfast cpp,
Traceback (most recent call last):
File "/usr/local/lib/python2.7/dist-packages/openravepy/_openravepy_/ikfast.py", line 9521, in
chaintree = solver.generateIkSolver(options.baselink,options.eelink,options.freeindices,solvefn=solvefn)
File "/usr/local/lib/python2.7/dist-packages/openravepy/_openravepy_/ikfast.py", line 2281, in generateIkSolver
chaintree = solvefn(self, LinksRaw, jointvars, isolvejointvars)
File "/usr/local/lib/python2.7/dist-packages/openravepy/_openravepy_/ikfast.py", line 2796, in solveFullIK_TranslationDirection5D
coupledsolutions,usedvars = solvemethod(rawpolyeqs2[index],newsolvejointvars,endbranchtree=[AST.SolverSequence([endbranchtree2])], AllEquationsExtra=AllEquations)
File "/usr/local/lib/python2.7/dist-packages/openravepy/_openravepy_/ikfast.py", line 5226, in solveLiWoernleHiller
hassinglevariable |= any([all([__builtin__.sum(monom)==monom[i] for monom in newpeq.monoms()]) for i in range(3)])
IndexError: tuple index out of range
Is there a recommended way to get IKfast to generate a cpp or maybe even get the normal KDL to work reliably for my 5 dof system? I would really appreciate any kind of help to get this to work, thanks
Here's the picture of the bot from RViz
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