CLM, a global optimisation method applied to FEM updating

A new efficient global optimisation technique, named Coupled Local Minimisers (CLM), will be investigated in the paper. In CLM, a cooperative search mechanism is set up using an ensemble of local optimisers, each starting from a different point in the search space. The local optimisation processes are coupled ’on-line’ by interaction and information exchange. The combination of a fast convergence, due to the derivative information used in the local algorithms, with the capability of finding the global minimum, resulting from the parallel strategy, guarantees an efficient global optimisation algorithm. The principal idea of CLM is worked out in the paper. A test function with several local minima is minimised successfully. Next, CLM is applied to Finite Element Model (FEM) Updating using experimental modal data and illustrated with a simulated example of a damaged beam. The damage pattern can be identified accurately using the CLM-method.