Selection of Input Force Locations when Determining Blocked Forces

Blocked force determination is an alternative to the more customary method of using transfer path analysis to determine inverse forces. The primary advantage of the approach is that the source does not need to be detached from the machine. Results are valid so long as the source and machine are intact and the blocked forces are determined at the interface between the source and machine. In this research, finite element analysis is used to determine a pseudo set of blocked forces between two plates joined along an edge. The number of necessary force locations needed to model the edge is determined for different frequency ranges. In addition, strategies for selecting the number and locations for response points are recommended. Results are assessed by comparing the predicted and simulated responses at selected receiver points which were not used for the inverse force analysis.