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How to make fmincon search through the all domain of definition?

How to make fmincon search through the all domain of definition?

How to make fmincon search through the all domain of definition?

(OP)
Hello to everyone,
i am implementing a driver model with look-ahead function. Herefore, i have to use an optimization algorithm, which look in a finite future horizont, to define Np optimal control signals, so that a specific Cost function J(trade off between deviation to reference trajectory and Consumption), can be minimized. That means if for example i am only minimizing J over the acceleration pedal Ua, then i call fmincon from a level 2 s-function within the main Car-model like this for example:
Uopt = fmincon(@(u)fun(u),U0,[],[],[],[],-100,100,@nonlcon,options).
whereby U0 is a vector of size = [Npx1]. Within teh function fun a simplified vehicle model, is then called with u as input and the velocities over the Np time steps as output!
My questions are then:
1) since i set DiffMinChange=0.1 and DiffMaxChange = 100, why does fmincon only try pulses of u=0.1 at different time steps, and doesn't try bigger values within the range [0.1 ,100]??? Fmincon then stops since(i think) with a single input of 0.1 as pedal position the cost function doesn't vary very much. It would be something else if it would ahve tried u = [100 50 80 10 9] in case Np = 5 for example.

2) the all process of calling the simulink model is really, really slow. Is there a more convenient way to implement predictive control, when i don't have the predictive control toolbox???
I am new to the site and i hope we will have some great discussions.
Thanks for your time and help.
Armand

RE: How to make fmincon search through the all domain of definition?

(OP)
well the prediction will actually also controls the shifting-strategy for the manual gearbox(that was just a small part of the problems) and since i'am simulating an hybid driveline, i tought it was the right forum.

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