Simplex optimisation with fminsearch using a Simulink model

Hi every one,

I have some problem with a basic optimisation using fminsearch. I'm trying to find the optimal values of three parameters descibing the rolling resistance of a vehicle in coastdown simulation. I have a Simulink model that simulates the coastdown and among the inputs there are also the three parameters that I have to optimize, they are set as constant blocks and theoretically the values are read from the workspace. I have a set of experimental data to fit with my model and the objective function for fminsearch is the mean square error between the experimental dataset and the simulation results of the model in terms of velocities. The Simulink is called inside the user defined function for the computation of the mean square error every time.

The principal problem is that the variables are not updated and every input of the three parameters I set as x0 (starting point of fminsearch) is also the result of the optimisation.

What can I do to solve my problem?

Thank you for your time, Daniele

Answer 1

[Manas Meena]

You can refer to the following link to learn about Simplex optimisation using fminsearch

• https://www.mathworks.com/matlabcentral/answers/415890-simplex-optimisation-using-fminsearch?s_tid=answers_rc1-2_p2_MLT