Sensor placement for on-orbit modal identification and correlation of large space structures

A method is presented for the selection of a set of sensor locations from a larger candidate set for the purpose of on-orbit identification and correlation of large space structures. The method ranks the candidate sensor locations according to their contribution to the linear independence of the target modal partitions. In an iterative manner, locations that do not contribute significantly are removed. The final sensor configuration tends to maximize the trace and determinant and minimize the condition number of the Fisher information matrix corresponding to the target modal partitions. This leads to better estimates and improved correlation. Advantages of the method include its computationally nonintensive nature compared with exhaustive search techniques found in the literature and the benefit of physical insight into the ranking and ultimate selection of sensor locations. The method is successfully applied to the selection of sensor locations for identification and correlation of a set of target modes for the structural characterization of a proposed large space structure. The final sensor configuration provides superor Fisher information matrix trace, determinant, and condition number values compared to other methods of sensor selection. (Author)