ik service call fails

Question

I'm doing a little IK work with a 7-DOF arm using ROS' IK service calls but with little luck. I want the ability to use either the collision free IK or just the regular IK service. I can connect to and see the /get_ik, /get_ik_solver_info, and /get_constraint_aware_ik with no problem, but when I send the solver a pose, I get the error:

Inverse kinematics service call failed

If I run the collision free IK with the same exact pose, it has no problem finding a solution and returning from the service. I can dig through the service calls and try and hunt down why it might err when the only difference is which service I connect to, but I was hoping someone here may know the culprit or why it may be acting up like this.

I might also add that yesterday before I left work, I had the get_ik service call working with no issues. Today, without changing a single thing, I have yet to be able to return successfully from the ik service call. I have restarted my simulation multiple times and verfied the rosservice is started as well as any controller I need.

Thanks.

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Originally posted by seth_g on ROS Answers with karma: 178 on 2011-12-22

Post score: 0

Answer 1

I would suggest that you try changing the resolution that the IK solver works in. In your constraint_aware launch file, add a parameter of:

 <param name="arm/epsilon" value="0.001" />

Where "arm" is the name of your arm. The default value is 1e-5, I've found that 1e-3 or 1e-4 tends to work better for my arm.

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Originally posted by fergs with karma: 13902 on 2011-12-24

This answer was ACCEPTED on the original site

Post score: 0