System Identification: An experimental verification

System identification may be defined as the process of determining a model of a dynamic system using observed system input-output data. The identification of dynamic systems through the use of experimental data is of considerable importance in engineering since it provides information about system parameters which is useful in predicting behavior and evaluating performance. Traditional methods of System Identification are usually time-consuming, costly, and difficult to use in other than a product development environment. Within the last decade, more sophisticated techniques for System Identification have been developed that can simultaneously estimate many parameters accurately and repeatedly. These modern techniques are, in addition, efficient, easy to use, inexpensive, and readily adaptable to manufacturing and in-the-field environments where they can be used to evaluate product quality and performance. This paper describes the use of one such System Identification algorithm to estimate several mechanical parameters of 8-inch hard-disk drive spindles in a manufacturing-like setting. The results obtained are in excellent agreement with results acquired by more conventional methods, and demonstrate the potential benefits of System Identification techniques in evaluating product quality and performance.