Why "Index in position 2 exceeds array bounds." ?

Hey guys,

i wanted to identify system parameters of a DC-Motor with Simulink and two matlab scripts. The scripts I want to use, should use the least square error and optimise params with fminsearch.

This is my IdentifyMotor.m file:

clear; close all
global t velocity  K T1 T2 k
load Sprungantwort_Encodermotor.txt
velocity = Sprungantwort_Encodermotor(1:800);
t = (0:length(velocity)-1)*100e-6;
clear Sprungantwort_Encodermotor
plot(t, velocity)
grid
xlabel('time [usec]')
ylabel('velocity')
K = 800;
T1 = 2;
T2 = 1;
figure(2)
hold
k = 0;
p = [T1 T2]
options = optimset('MaxFunEvals', 60);
p = fminsearch('SumSquareErrors', p, options)
figure (2)
hold

This is the SumSquareErrors.m :

function summe = SumSquareErrors(p)
global t velocity simResponse K T1 T2 k
T1 = abs(p(1))
T2 = abs(p(2))
if T1 < 0.01
    T1 = 0.01
end
if T2 < 0.01
    T2 = 0.01
end
sim('SimSystem')
figure(1)
plot(t,velocity,simResponse(:,1),simResponse(:,2),'r')
grid
xlabel('time [usec]')
ylabel('velocity')
title('system identificaion')
q = velocity-simResponse(:,2);
summe = sum((q.^2))
figure(2)
k=k+1;
plot(k,summe,'*')

The errors i get are the following:

Index in position 2 exceeds array bounds.
Error in SumSquareErrors (line 13)
plot(t,velocity,simResponse(:,1),simResponse(:,2),'r')

Error in fminsearch (line 200)
fv(:,1) = funfcn(x,varargin{:});

Error in IdentifyMotor (line 19)
p = fminsearch('SumSquareErrors', p, options)

The problem i have is that simResponse doesn't show up in my Workspace while im running those scripts. But it is declared in the Simulink-Model and also in the SumSquareErrors file. I tried to work with toWorkspace-Blocks but that didn't helped either...

Can anyone help me?

[Image Analyst]

Can you set a breakpoint at that line? Then try this

>> whos simResponse

Evidently simResponse has only one column.

[Tim Brachat]

thank you! I debugged the script and noticed that i assigned simResponse the wrong way