For some strange reason the kalman function doesn't work on my MATLAB 2008b even with examples from the MATLAB documentation it fails
??? Undefined function or variable
'Nu'.
Error in ==> ss.kalman at 136
known = 1:Nu;
After editing the kalman function I discovered that the Nu variable isn't initialized but it's used many times on the code, thus the error.
Can someone with the Control System Toolbox™ check it out?
Example — Designing an LQG Servo Controller , this is from MATLAB 2008b documentation, it should work but it doesn't because of the missing Nu initialization on the kalman function.
A = [0 1 0;0 0 1;1 0 0];
B = [0.3 1;0 1;-0.3 0.9];
G = [-0.7 1.12; -1.17 1; .14 1.5];
C = [1.9 1.3 1];
D = [0.53 -0.61];
H = [-1.2 -0.89];
sys = ss(A,[B G],C,[D H])
nx = 3;
ny = 1;
Q = blkdiag(0.1*eye(nx),eye(ny));
R = [1 0;0 2];
K = lqi(ss(A,B,C,D),Q,R)
Qn = [4 2;2 1];
Rn = 0.7;
kest = kalman(sys,Qn,Rn);
trksys = lqgtrack(kest,K)
