Candidate Set DOF

 

The next step in the model preparation is to determine the candidate set DOF. For each FEM configuration the Iterative Residual Kinetic Energy algorithm was employed to start with 2 DOF and build up a set of 500 DOF by iteratively adding DOF to minimize the residual kinetic energy of the first 10 modes. This process was performed independently for the two FEMs in truck_wload_fem_irke.dat and truck_fem_irke.dat using DMAP alter fast_iter_rke6 which writes the candidate set DOF to the punch file in DMIG format. The DMIG matrices are converted to ASET cards using Matlab function pch2aset.m6. The resulting candidate set of each FEM is in truck_wload_irke.aset and truck_irke.aset.

After the candidate set of DOF has been determined for each FEM configuration the union of the two sets should be created. This ensures that the DOF that are selected by the two IRKE analyses that are common to both structures are present in each FEM’s candidate set. The union of the two sets of DOF was created, then intersected with each FEM configuration DOF to generate truck_wload_union_irke.aset and truck_union_irke.aset.