A central composite design based fuzzy logic for optimization of drilling parameters on natural fiber reinforced composite

Machining of polymeric composite is inevitable during assembly of components. In view of making holes on structural composites, drilling is essential and a study to optimize the machining parameters is very important. The present study has been made to investigate the defaces and cutting forces associated during drilling of natural fiber reinforced plastics. Plastic composite has been manufactured using chemically treated vetiveria zizanioides as the reinforcement and polyester as the matrix. The composite has been drilled several times on the basis of central composite design. Speed and feed rate of the spindle, point angle and diameter of the tool are considered as the input parameters. Deface of each hole during entry and exit, thrust force and torque have been measured as the output parameters. A fuzzy model has been created and a comparative study between the central composite design and fuzzy model is made. The design has been optimized with the objective of minimizing the output parameters and a set of confirmatory experiments have been conducted. The central composite model has been validated by comparing it with the fuzzy model and confirmatory runs. The comparison presented only a minimal error and hence the modeling by central composite design and fuzzy are consummate.