EAIK does not find solutions for spherical redundant robots

[JonathanKuelz]

It seems that EAIK does not find solutions for some robots even thought they are spherical (hasKnownDecomposition == True).

I think all robots I have seen with this issue so far are redundant. Here is an example in DH parameters:

alpha_test = np.array([-1.5708,  1.5708,  1.5708,  1.5708,  1.5708, -1.5708])
a_test = np.array([0.2951, 0.4270, 0.0000, 0.0000, 0.0000, 0.1680])
d_test = np.array([0.0000, 0.9954, 0.6455, 0.0000, 0.0000, 0.0000])
# a_test = np.array([0.2951, 0.4270, 0.2000, 0.0000, 0.0000, 0.1680])  --> This fixes the issue

(this robot fails for basically any pose it can reach)

In theory, EAIK should be able to solve these, shouldn't it?

[OstermD]

This robot is indeed redundant in every configuration, as the last four axes intersect. As none of the other axes intersect, SP5 becomes part of its decomposition, which then fails for every desired pose.

See #17 for further information