Hey Muhammad,
The issue seems to be that the simulation results are not correctly captured and used for error calculations, which might be due to improper handling of workspace variables or incorrect assignment of simulation outputs. To address this, You need to ensure that variables are accurately assigned and retrieved from the base workspace, and that the simulation results are correctly captured and utilized. The approach involves careful management of the scope of variables and ensuring proper evaluation and assignment of simulation data.
In the optimization_PID function, I made the following change to ensure the ITAE values are fetched directly from the base workspace:
function cost = optimization_PID(k)
assignin("base", "k", k);
sim("Model1.slx");
itae_values = evalin("base", "ITAE.Data");
cost = sum(itae_values);
end
In the main experiment function, I used evalin to fetch simulation results, ensuring variables like DriveCycle, tout, and v_act_lim are accurately captured. This ensures that the interpolated simulated results match the drive cycle time points and that error values are validated to exclude infinite values:
function [mean_abs_error] = Experiment2Function1(params)
tend = params.time;
start_simulation_time = tic;
no_var = 2;
lb = [params.lbP params.lbI];
ub = [params.ubP params.ubI];
ga_opt = optimoptions('ga','Display','off','Generations',params.generations,'PopulationSize',params.population,'PlotFcns',@gaplotbestf);
obj_fn = @(k) optimization_PID(k);
[k, best] = ga((obj_fn),no_var,[],[],[],[],lb,ub,[],ga_opt)
simulation_time = toc(start_simulation_time);
tend = 1800;
sim("Model1.slx")
driveCycleTime = evalin("base", "DriveCycle(:,1)");
driveCycleSpeed = evalin("base", "DriveCycle(:,2)");
index1800s = driveCycleTime <= tend;
driveCycle1800s = [driveCycleTime(index1800s), driveCycleSpeed(index1800s)];
simulatedTime = evalin("base", "tout(tout <= tend)");
simulatedSpeed = evalin("base", "v_act_lim(tout <= tend)");
simulatedSpeedInterp = interp1(simulatedTime, simulatedSpeed, driveCycle1800s(:, 1), 'linear');
error = (driveCycle1800s(:, 2) - simulatedSpeedInterp)./ driveCycle1800s(:,2)*100;
abs_error = abs(error);
validIndices = isfinite(abs_error);
validAbsError = abs_error(validIndices);
mean_abs_error = mean(validAbsError)
end
Hope this helps!
