Fanuc offer a 5-axis version of the 200iD robot the 200iD/4SH. The 5-axis configuration seems to have advantages in some applications, since there is no singularity possible where joint 4 lines up with the joint 6 (there is no joint 4).
Firstly is this correct that the 5-axis robot avoids this singularity?
And secondly, is it possible to move a 6-axis Fanuc robot (or other brand) in a '5-axis mode' fixing joint 4 for particular moves?