[en] The metal connector is one of the commonly used connectors in mechanical systems. Its structure design is a typical multi-objective optimization problem which is constrained by strength, stiffness, fatigue life and stability, etc. In the Ω-shaped connectors were taken as the research object, the effects of structural parameters of which were analyzed under the centrifugal force on two key mechanical properties, stress and stiffness. And an optimization model was established with the aim of reducing stress and stiffness by finite element method. The structure optimization was realized by multi-objective genetic algorithm (MOGA), changing the relatively independent status of the strength and stiffness design process for a long time. And the ability of flexible connectors' structure design was also improved. (authors)

[en] Bellows is an important connected part of flexible rotor. One of the important performance parameter of bellows is bending stiffness. It is difficult to measure bending angle because expansion joint of bellows is small and deformation is tiny under load. So it is essential to study the measuring method of bending stiffness of bellows for good test. Three measuring methods of bending stiffness of bellows are method of axial loading, method of the horizontal support and method of static vibrational excitation. It is concluded that the method of axial loading is fit for measuring bending stiffness of bellows in flexible rotor by studying. (authors)