Fuzzy process capability indices for simple linear profile

Process capability indices are numerical tools that quantify how well a process can meet customer requirements, specifications or engineering tolerances. In real world, in some cases we are faced with imprecise data. So, fuzzy logic is engaged to deal with them. This paper develops two fuzzy methods for measuring the process capability in simple linear profiles in the circumstances in which lower and upper specification limits are imprecise. Furthermore, numerical example is presented to illustrate the applicability of the proposed methods.