On the tradeoff control to concurrent product and process design

Concurrent product and process design may be modeled as a generalized two-objective optimization problem. The first objective characterizes "product design" with the aim of best enhancing product functionality, while the second objective corresponds to "process design" with the aim of minimizing overall manufacturing costs. However. these performing goals may be mutually conflicting in arriving concurrently at their respective optima; therefore, design tradeoffs must be settled in order to achieve a best compromise design. In this work, an adaptive tradeoff parameter, lambda(0 less than or equal to lambda less than or equal to 1.0), is introduced to adaptively control the progressive design tradeoffs between the two performing goals by calibrating the tradeoff parameter lambda over the interval of 0 to 1.0. A fuzzy control scheme is proposed to control the iteration-based design tradeoffs with concurrent design progression for an optimal compromise settlement in design. Three design models are presented to accommodate different tradeoff scenarios in concurrent design. The proposed approach is illustrated through the case study of a welded beam design.