Multi-axial simulation of aircraft cabin vibrations

The systematic investigation of the vibration comfort of air passengers requires the multi-axial simulation of aircraft cabin vibrations. Preconditions for significant experiments are a vibration test facility and methods for test preparation, \nperformance and evaluation. This report describes the upgrade of an existing vibration test facility as well as the development of appropriate methods and test approaches. First steps consisted of a renewal of basic hydraulic components, an adaptation and overhaul of electric and electronic equipment, the development of a safety concept and a formulation of a test procedure for human test person \nundergoing vibration tests. Based on this, a certification of the vibration test facility and a concession for vibration tests on humans could be achieved. The existing uniaxial control system was extended and a concept for the reproduction of multiaxial vibrations was developed. It could be shown that a high quality of signal reproduction is possible. In next steps, comprehensive software tools for the analysis, comfort evaluation and processing of vibration test data were developed. Finally, a test campaign with human test person was performed. Aircraft vibrations during gusts and turbulences were simulated and the vibrations of the vibration table as well as the physiological reactions of human test person were measured. Summarizing the results and experiences it can be concluded that the vibration test facility, the utilized equipment, the employed tools and the overall approach were able to fulfill all requirements for these and future vibration tests on human test person. Further \nimprovements of the vibration simulation with respect to effort, time and reproduction quality can be expected from an online multi-axial control system.