Abstract：To overcome the obstacles of measuring rotational dynamic flexibility and exerting moment excitation on the substructure which lie in experimental component mode synthesis method, a numerical differentiation formula is utilized to estimate the rotational displacement, the moment excitation is represented by a parallel force system, and then a newly indirect measuring technique for the rotational dynamic flexibility is developed. By measuring a set of force induced translational dynamic flexibilities at a limited number of points using hammer excitation method or frequency sweeping method, it is possible to express approximately the moment induced rotational dynamic flexibilities in terms of those measured quantities. The merits of this indirect measuring technique are that no attached T block is needed, moment excitation is also not needed, and even the parallel force excitations are not needed. The indirect measurement of rotational dynamic flexibility is then brought into the fixed frequency residual dynamic flexibility based experimental component mode synthesis method to satisfy the rotational compatibility at the interface of the substructures. Finally, numerical examples have demonstrated the validity and efficiency of the proposed method.
2013, Vol. 32 
