Global static and dynamic car body stiffness based on a single experimental modal analysis test

Global car body stiffness is an important design attribute in vehicle design. Therefore accurate characterization of this stiffness is needed. The current industrial method for static stiffness determination has several downsides, amongst others its time consuming set-up preparation. Dynamic characterization by means of modal analysis on the other hand has high repeatability and a less time consuming set-up preparation. This paper describes and experimentally validates the industrial implementation of a method to overcome the downsides of the classic static test by determining both global static, as well as dynamic stiffness based on a single modal analysis test. The method combines several techniques available in literature. Theory behind the method is elaborated, simulation tests show the potential of the method and finally experimental validation on a full body-in-white proves industrial applicability of the proposed technique.