The control strategy available on the machine is the use of a
fuzzy controller to adjust the IEG according to a desired
machining current. The use of this approach for the ECM
processed was pointed out by Labib et al. [45] who highlighted
the necessity for the controller to have decision making
capabilities. Since the PECM process is very hard to mathematically
model, conventional control approaches such as
proportional-integral-derivative (PID) or state space controllers
are limited and based on the linearisation of the process
function (and therefore approximation). They observed that
the occurrence of sparking was efficiently prevented when
fuzzy logic control (FLC) was applied to the ECM process
and encouraged further research to develop FLCs for the
EMM process. Moreover, it is worth mentioning that fuzzy
logic was also used to control the process in EDM,Wire EDM
[46, 47] and electro-chemical discharge machining (ECDM)
[48, 49].