Like the term artificial intelligence, the term fuzzy logic is bound to intrigue as well as confuse. Its application to EDM is especially interesting. Fuzzy logic means that the control unit does not follow strict rules to reach conclusions or arrive at decisions, but weighs options according to desired results. This approach is appropriate in situations where questions may have more than one correct answer. "Correctness" is determined by the priorities of the user, which may vary from case to case.
Fuzzy logic is such a promising development for EDM because it encourages strategic planning while enhancing automatic operation. For example, the cutting conditions to produce high accuracy and fine surface finish are unlike those to produce fast cutting speed. Choosing the desired results is a strategic decision that implies various machining parameters and power settings, but selecting the right parameters and settings is complex. It is the nature of EDM that the variables are both numerous and highly interrelated. Managing these variables is the key to successful and efficient EDM, and fuzzy logic supposedly lets any user manage them with the expertise of an old pro.
Novick’s control, which is based on 32/64-bit computer processing, queries the user about the given workpiece material, its size, and the electrode. The user is then asked to indicate desired cutting speed, surface finish, and accuracy (in order of priority), along with how many passes or cuts the user plans for. The unit responds, based on fuzzy logic, by presenting a series of "results", based on the priorities of the user.
At this point, the user can look over the series and "think again", perhaps choosing an alternative to the top-listed recommendation. For example, if an extremely fine surface finish and very high accuracy are given top priority, cutting times are likely to be very long. The user may decide that they are too long. By scanning the list, the user can review the alternatives and see at a glance what finishes and accuracies are possible at faster speeds. The appropriate power settings for the final selection are established automatically.