Inverse kinematics error / no valid IK solution found

[timonegk]

I try to use IKFast to generate an analytical solution for a 6R robot leg.
The generated solution does not pass the tests (~7% success rate).
I attached the dae file of the robot (txt file ending because of github's restrictions).
Do you have any idea on the source of the problem?

robot_leg_simple.dae.txt
wrapper.xml.txt