High-order interval type-2 Takagi-Sugeno-Kang fuzzy logic system and its application in acoustic emission signal modeling in turning process

Type-2 fuzzy logic systems (FLSs) are gaining in popularity because of their capacity to handle rule uncertainties in a more complete way. Moreover, higher-order interval type-2 (IT2) FLS can reduce drastically the number of rules needed to perform the approximation and improve transparency and interpretation in many high-dimensional systems. This paper presents architecture and inference engine of generalized IT2 Takagi-Sugeno-Kang (TSK) FLS and the design method of higher-order IT2 FLS. An experimental acoustic emission (AE) signal modeling using a second-order IT2 TSK FLS in turning process is given to demonstrate the differences between the first-order and second-order IT2 FLSs and the advantage and efficiency of high-order IT2 FLS. The estimation of uncertainty of AE could be of great value to a decision maker and used to investigate tool wear condition during the machining process.