If you want an easy way to test if KDL can solve it, the arm_kinematics package has some easy structure for that. http://www.ros.org/wiki/arm_kinematics -DL!! On Tue, Nov 9, 2010 at 3:27 AM, Herman Bruyninckx wrote: > On Tue, 9 Nov 2010, Jeroen Willems wrote: > >> I have a question regarding the inverse kinematics using KDL. >> >> I would like to use carttojnt of the inverse kinematics solver. >> The problem is I have to use a destination frame as input. >> I'm using something similar to a elbow manipulator so you can imagine I only want a reference position. >> The arm only can have 2 poses to a reference position, to get the rotational part of the frame I actually have to get the joint positions to calculate it (correct me if I'm wrong). >> >> So >> 1. Am I right? >> 2. Could I use KDL to compute the IK or should I use an analytic solution? > > The major issue with your problem is that "IK" does not make too much sense > for a 2DOF system: when you don't take precautions the input frame will > never lie in the span of your 2DOF, so you will have make a "projection" > from the full 6D space onto your 2D subspace. KDL has algorithms to do > that, but they make choices about how to project that might not correspond > to your intuition. But that's inevitable. > > So, please try to formulate exactly what kind of input you would like or > need to have. > > Herman > _______________________________________________ > ros-users mailing list > ros-users@code.ros.org > https://code.ros.org/mailman/listinfo/ros-users >