How to maintain eigenvalues sequence
4 Ansichten (letzte 30 Tage)
Ältere Kommentare anzeigen
Hello,
I have to draw root-locus for longitudinal motion; Short Period Mode and Phugoid Mode. Here is a code
%% Dynamics
Vp = 111.174
A_lon = [-0.0283 0.3139 -11.0665 -32.0344;
-0.4204 -1.5452 108.6931 -3.2616;
0.0205 -0.2011 -3.5080 0;
0 0 1 0]
B_lon = [0.0115 0.1150;
-0.2185 0;
-0.3591 0;
0 0]
C_lon = [1 0 0 0;
0 -1 0 Vp]
%% LQR Servo Design
A_servo = [A_lon zeros(4,2);
-C_lon zeros(2,2)]
B_servo = [B_lon ; zeros(2,2)]
n = 100; a = logspace(-2,2,n);
for i = 1:n
Q = a(i)*[1 0 0 0 0 0;
0 1 0 -Vp 0 0;
0 0 0 0 0 0;
0 -Vp 0 power(Vp,2) 0 0;
0 0 0 0 1 0;
0 0 0 0 0 1];
R = eye(2);
[K,S,P] = lqr(A_servo,B_servo,Q,R);
p_cl = P;
cl_sh(i,1) = p_cl(5); cl_sh(i,2) = p_cl(6);
cl_ph(i,1) = p_cl(3); cl_ph(i,2) = p_cl(4);
end
%% Plot
figure;
plot(real(cl_sh(:,1)), imag(cl_sh(:,1)), '+', real(cl_sh(:,2)), imag(cl_sh(:,2)), 'x', MarkerSize=5);
title("Root Locus of Short Period Mode")
xlabel("real")
ylabel("imag")
grid on;
figure;
plot(real(cl_ph(:,1)), imag(cl_ph(:,1)), '+', real(cl_ph(:,2)), imag(cl_ph(:,2)), 'x', MarkerSize=5)
title("Root Locus of Phugoid Mode")
xlabel("real")
ylabel("imag")
grid on;
When the code is executed, the sequence of eigenvalues is misaligned from some point in the iteration statement and the point was depended on weight of Q, R matrix. So when the sequence of eigenvalues is out of order from a certain point in time like this, how should we modify the code to solve it?
0 Kommentare
Antworten (0)
Siehe auch
Kategorien
Mehr zu State-Space Control Design and Estimation finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!