Combination of data sets for system identification

A multiple-cost approach is proposed which is found to be extremely powerful and useful. A relationship between the results obtained using this approach and those obtained using straightforward individual-run identification is derived, and its accuracy investigated. Using this relationship, it is possible to obtain estimates for multiple-cost identification results on the basis of individual-run results, allowing existing single-run software and techniques to be used unchanged for multiple-cost identification. An example is given of the use of multiple-cost identification with flight data for a Puma helicopter; good results are obtained and some important issues highlighted and discussed.