Tolerance synthesis by a new method for system reliability-based optimization

The performance–cost ratio of a product may be significantly improved by a better tolerance assignment. Current practice guided by experience usually leads to a conservative and costly design. Because yield in mechanical engineering is analogous to system reliability in structural engineering, this article applies a system reliability-based optimization formulation to tolerance synthesis and presents a sequential approximate programming method. This method is an extension of the approach for the optimization with component reliability constraints. Two often-quoted examples are analyzed in detail to illustrate its effectiveness and a strategy for tolerance assignment is recommended.