Application of Transfer Path Analysis (TPA) to a Mechanical Structure with a Variety of Transfer Paths

In a typical mechanical product such as an automobile or construction machinery, it is important to identify deformation modes, for which experiments and analyses can result in significant improvements. It is also important to consider how to improve the structure with high rigidity by using a technique such as the strain energy method in conventional design and development. However, the abovementioned method often generates conflicting results with regard to weight saving and cost reduction of development requirements. Transfer path analysis (TPA) using the finite element method (FEM) is an effective way to reduce noise and vibration in the automobile with respect to these issues. TPA can reveal the transfer path from the input to the response of the output point and the contribution of the path, and to efficiently consider improved responses. TPA using FEM was applied to a mechanical structure with a variety of transfer paths, and evaluated the contribution of the vibration transfer path toward improving ride comfort. Analysis revealed the contribution of the partial structure of a vibration transmission path not found in the conventional technique. A comparison of analytical solutions revealed the differences between TPA and the conventional strain energy method. Studying the improvements in the structure based on these results led to a reduction in output points. This paper discusses the mechanism of vibration response and response reduction, their effectiveness, and issues regarding the future developments of TPA.