Programmable controller with unclear control function, unclear control process and unclear control monitoring process

摘要

A programmable controller or PC (41) to which fuzzy control logic principles have been applied is disclosed. The controller improves operational speed by performing several of the fuzzy logic functions in the A/D and D/A converters (50, 60) traditionally used in PC units, thereby allowing portions of a fuzzy logic control operation to proceed in parallel and independently. The invention dispenses with the use of look-up tables and the like for fuzzy membership functions, fuzzy output functions, etc., by defining the functions typically in terms of three points in an orthogonal coordinate system, saving memory space. The invention also includes a fuzzy control process having the described aspects and a method of monitoring a PC or PCs having a fuzzy control function.