This paper presents a new concept and procedure for structural modeling of linear and nonlinear systems. Both concept and procedure are based on an identical linear condition equation in the frequency domain. This consists of the structural parameters and a group function, which can be calculated from input/output data, and describes experimentally the dynamic behaviour of the system. By using this condition equation, not only can the structural parameters be estimated directly, but the model can be examinated and improved out effectively. In addition, the deviation of a model can be simply recognized, and new information for further improvement of the model can be generated. Hence, an accurate structural model can be obtained by using this procedure. (C) Elsevier, Paris.
