Co-ordinated axes are real or imaginary axes. A group of co-ordinated axes may be implemented by first implementing the real axes (methodology described on previous pages) and then the group.

In a slave axis group, the master axis may be real, imaginary or external and the slave axes may be real or imaginary. Implementing a slave axis group first entails implementing the independent axes which make up this group, following the methodology described on the previous pages, and then the group.