MOVING FORCE IDENTIFICATION: OPTIMAL STATE ESTIMATION APPROACH

Existing techniques to identify moving forces exhibit the common weakness of having large fluctuations in the identified results. A new method of moving force identification is developed in this paper making use of the dynamic programming technique to overcome this weakness. The forces in the state-space formulation of the dynamic system are identified in the time domain using a recursive formula based on several distributed sensor measurements, and responses of the structure are reconstructed using the identified forces for comparison. Like all inverse problems, the computation is ill-conditioned. However, the dynamic programming technique inherently provides bounds to the ill-conditioned forces, and results from the simulation studies and laboratory work show great improvements over existing methods in the accuracy of identification.

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