The default rotation parametrization of Inverse Kinematics uses quaternions but it causes Ipopt crashes

[S-Dafarra]

We (@Yeshasvitvs ) were facing a strange segfault problem when using the IK. Here the test. By adding the following line

ik.setRotationParametrization(iDynTree::InverseKinematicsRotationParametrizationRollPitchYaw);

it started working as expected. The problem is that by default iDynTree::InverseKinematicsRotationParametrizationQuaternion is used, as can be see here.

Also, by using a verbose output, IPOPT's derivative checker find several issues.

[traversaro]

The derivative problem for quaternion is unfortunately a known issue, see https://github.com/robotology/idyntree/issues/282#issue-220883630, but indeed:

• it is poorly documented
• the default choice should definitely be a working one, not the experimental one.