Fuzzy Controller where i and j = 0~6, Ai and Bj are fuzzy number, and cj,i is real number. The graph of fuzzification and fuzzy rule table is shown in Fig. 4. (d) Construct the fuzzy system uf (s,ds) by using the singleton fuzzifier, product-inference rule, and central average defuzzifier method. Although there are total 49 fuzzy rules in Fig. 4 will be inferred, actually only 4 fuzzy rules can be effectively excited to generate a non-zero output. Therefore, the (16) can be replaced by the following expression:

Fuzzy Controller Fig.2 The symmetrical triangular membership function of e and de, fuzzy rule table, fuzzy inference and fuzzification

Fuzzy Controller PL PMPSZEPL PMPSZENSPM PL PMPSZENSNMPS PLPMPSZENSNMNLZE PMPSZENSNMNL NS PSZENSNMNL NM ZENSNMNL PLPMPSZENSNMNL e de uf Fuzzy rule table PL (positive large) ， PM (positive middle) ， PS (positive small) ， ZE (zero error) ， NS (negative small) ， NM (negative middle) ， NL (negative large) 。

Fuzzy Controller e de uf Rule table before adjusted

II. Simulation FC in Matlab