Structure-Borne Prediction on a Tire-Suspension Assembly Using Experimental Invariant Spindle Forces

Road induced noise is getting more and more significant in context of the electrification of the powertrain. The automotive industry is seeking for technologies to predict the contribution of vehicle components upfront, early in the development process. Classical Transfer Path Analysis (TPA) is a well-established technique that successfully identifies the transmission paths of noise and vibration from different excitation sources to the target responses. But it has a drawback: it requires the physical availability of the full vehicle. To achieve shorter development cycles, to avoid costly time-consuming design iterations and due to the limited availability of prototypes, engineers derived a method that addresses these requirements. Component-based TPA is a relatively new structure borne substructuring approach that allows to characterize the source excitation by a set of equivalent loads (blocked forces) independently from the receiver structure and to predict its behavior when coupled to different receivers. Frequency Based Substructuring, FBS, is applied in order to obtain the coupled assembly. However, there are a number of challenges affecting its applicability, such as the proper modelling of the coupling degrees of freedom and the difficulty to access the interface connection points. Geometrical reduction aims to solve those inconveniences. This paper aims to investigate these challenges of component-based TPA by measurements on a tire-wheel suspension in static condition. The source component (the tire-wheel) is characterized by a set of blocked forces and transfer functions identified on a dedicated tire-wheel test-rig. These calculated loads are combined with the FRFs of the fully assembled system. The FRFs are calculated by using experimental substructuring methods. The sensitivity of applying FBS together with geometrical reduction in the frame of component-based TPA will be analyzed.