Attributing to variations of process capability index and tolerance in aircraft manufacturing,such cases will occur that the assembly quality specifications were violated or the manufacturing cost fluctuated a lot.So,a novel tolerancing methodology based on feasible and sensitive robust design was
developed.On one hand,taking into account the effects of design parameters such as
tolerances on the assembly feasiblity,the feasible robust tolerancing could ensure the
achievement of the designed assembly function in occurrence of design variations.
On the other hand,the sensitive robust tolerancing took the effects of design parameters
on manufacturing cost and assembly quality into consideration,which could minimize the
influence of design variations on manufacturing cost and assembly accuracy.
Furthermore,a toleant lexicotraphic method was proposed to solve the multiobjective
optimization problem in feasible and sensitive robust tolerancing.Such factors as manufacturing costs, fluctuations of assembly quality and fluctuations of manufacturing cost were sorted according to their effects in tolerancing.Above all,the general tolerance with
minimized manufacturing cost could be achieved.Then,
under the tolerant constraint of minimized cost,the tolerance was deduced by minimizing
the fluctuation of assembly quality.Finally,under the tolerant constraints of cost and
fluctuation of assembly quality,the optimal tolerance with minimized cost fluctuation was
obtained.The proposed methodology was proved to be feasible and effective by
an example.