Optimized Fuzzy Logic for Motion Control

For any fuzzy logic application the first and foremost task is to select the optimumnumber and shape of membership functions such as bell shape, singleton, triangular, etc.for fuzzification; then it is equally essential to select the appropriate defuzzification method,such as COG, COM, MOM, etc. The sampling rate to execute the given command isanother important parameter. If these three parameters are optimally selected then theoutput response of motion controller will have a shorter rise time, less settling time,minimized overshoots/undershoots and negligible steady state error. Hence, the systematicstudy on selection of number and shape of membership function, selection of defuzzificationmethods and sampling time for speed control of PMDC micro motor is studiedexperimentally by applying LabVIEW software. The experimental results reveal that 7numbers of triangular membership functions, COG defuzzification method and 1millisecond (msec) sampling rate for labVIEW program execution are the optimumparameters for motion control.