Use of Single Point Interface Measures for Characterization of Attachments

Often components or subsystems are attached to other systems through multiple fasteners at multiple locations. Examples may include things like compressors, alternators, engine cradles, powertrain mounting systems, suspension systems, body structures or almost any other interface between components or subsystems. Often during early design stages, alternative component or subsystem configurations are being considered that can have very different interface characteristics, such as alternators with different number of mounting fasteners, or suspension systems with different number of body structure interface attachments. Given these different mounting configurations, it can be difficult to meaningfully compare the interface performance of the two components or subsystems. This paper will present a means of reducing multiple component connections down to a single point interface that is common between different designs such that the interface performance of the two components can be compared. Further, a method for applying this technique to both analysis and test data will be presented. This method reduces the responses at the individual physical attachment points down to the response at a single point interface. This geometric reduction can be done on both FE based data and test based data. Quantifying the performance of components or subsystem using this single point interface method enables high level comparisons between systems with very different interface characteristics.