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In order to generate in-flight acoustic and vibration fields inside an aircraft cabin mock-up, an N&V simulator was developed. The preliminary work on the development, setup and characterization of the N&V simulator will be presented. Firstly, an overview of the system will be given, including the desired input signals, followed by the presentation of the control software, which was developed to simplify the operation of the system by end users during routine testing. Secondly, the set-up strategy to adjust the reproduction of levels and spectrum of both acoustic and vibration fields will be presented, along with comparative vibroacoustics results between the mock-up and original in-flight recordings. Finally, a discussion on different methods for adjusting the simulator reproduction by means of optimal filtering is made, and further developments are presented.

Mechanical systems excited by vibratory point-sources tend to suffer from interference among axes, due to characteristics of the reproduction system or difficulties associated with the application of the excitation forces on the system's mass center. Thus, when it is necessary to excite the system independently in different directions, control techniques are needed for the correct reproduction of the desired signals. This work presents the developments for the reproduction of vibrations in two directions, on platforms employed as the base of seats of an aircraft cabin simulator. Each platform is independently excited by two orthogonal shakers, located in the geometrical center of the latter. Based on an evaluation of the degree of coupling between both orthogonal axes, signal processing solutions for the decoupling problem are proposed. Using SVD to diagonalize the transfer-function matrix, an independent base for the system was identified.