Some Investigations Related to Gradients for Aircraft Parameter Estimation
Abhay A. Pashilkar, R.V. Jategaonkar · Institutional Repository @ NAL (University of Southampton) · 1998
This report describes the implementation of the Modified Newton Raphson with Estimated Sensitivities (MNRES) for gradient computations of the output error method. This method of gradient computation was tested on a range of aircraft models and its performance compared with the well known Modified Newton Raphson (MNR) method using finite differences. The results of this study are reported here. The finite difference method was also compared with exact sensitivities computed for a linear aircraft model. The convergence behaviour of the MNR methods is sensitive to the quality of the gradient information. It was found that when there were convergence problems in the MNR methods, the Levenberg- Marquardt method performed better.