Files
PBSwissMX/matlab/StateSpaceControlDesign.m

257 lines
6.3 KiB
Matlab

function [ssc]=StateSpaceControlDesign(mot,motid)
% !!! first it need to run: [mot1,mot2]=identifyFxFyStage() tobuild a motor object !!!
%
% builds a state space controller designed for the plant.
% shows step answers of open and closed loop, also for the observer controller and the final discrete observer
%
% finally it opens a simulink observer file for testing
%References:
%http://ctms.engin.umich.edu/CTMS/index.php?example=Introduction&section=ControlStateSpace
%space state controller:
% web(fullfile(docroot, 'simulink/examples.html'))
% web(fullfile(docroot, 'simulink/examples/inverted-pendulum-with-animation.html'))
% web(fullfile(docroot, 'simulink/examples/double-spring-mass-system.html'))
%
% https://www.youtube.com/watch?v=Lax3etc837U
%ss_ol=mot.ssPlt;
ss_ol_plt=mot.ssPlt; %real plant (model of real plant)
ss_ol_plt.Name='open loop plant';
ss_ol_mdl=mot.ssMdl;%ssMdl; %simplified model (observable,controlable) for observer
ss_ol_mdl.Name='open loop model';
[Ap,Bp,Cp,Dp]=ssdata(ss_ol_plt);
[Am,Bm,Cm,Dm]=ssdata(ss_ol_mdl);
%sys=ss(sys.A,sys.B,sys.C(3,:),0); % this would reduce the outputs to position only
figure();h=bodeplot(ss_ol_plt,ss_ol_mdl);
setoptions(h,'IOGrouping','all')
% step answer on open loop:
t = 0:1E-4:.5;
u = ones(size(t));
xp0 = zeros(1,length(Ap));
xm0 = zeros(1,length(Am));
[yp,t,x] = lsim(ss_ol_plt,u,t,xp0);
[ym,t,x] = lsim(ss_ol_mdl,u,t,xm0);
figure();plot(t,yp,t,ym,'--');title('step on open loop (plant and model)');
legend('plt.iqMeas','plt.iqVolts','plt.actPos','mdl.iqMeas','mdl.iqVolts','mdl.actPos')
poles = eig(Am);
%w0=abs(poles);
%ang=angle(-poles);
%-------------------
%p=w0.*exp(j.*ang)
% *** space state controller ***
%
%place poles for the controller feedback
if motid==1
%2500rad/s = 397Hz -> locate poles here
%6300rad/s = 1027Hz -> locate poles here
if length(poles)==4
p1=-6300+2800i;
p2=-6200+1500i;
P=[p1 p1' p2 p2'];
else
p1=-3300+2800i;
p2=-2700+500i;
p3=-2500+10i;
%p1=-3300+2800i;
%p2=-1500+500i;
%p3=-1200+10i;
P=[p1 p1' p2 p2' p3 p3'];
end
else
%2500rad/s = 397Hz -> locate poles here
%6300rad/s = 1027Hz -> locate poles here
if length(poles)==4
p1=-6300+2800i;
p2=-6200+1500i;
P=[p1 p1' p2 p2'];
else
p1=-3300+2800i;
p2=-1900+130i;
p3=-2900+80i;
p4=-2300+450i;
p5=-2000+20i;
p6=-1500+10i;
%p1=-3300+2800i;
%p2=-1500+500i;
%p3=-1200+10i;
P=[p1 p1' p2 p2' p3 p3'];% p4 p4' p5 p5' p6 p6'];
end
end
K = place(Am,Bm,P);
%K = acker(Am,Bm,Pm);
V=-1./(Cm*(Am-Bm*K)^-1*Bm); %(from Lineare Regelsysteme2 (Glattfelder) page:173 )
%Nbar(2)=1; %the voltage stuff is crap for now
if length(V)>1
V=V(3); % only the position scaling needed
end
%prefilter to compensate non observable resonance frequencies
numV=mot.prefilt.Numerator{1};
denV=mot.prefilt.Denominator{1};
% step answer on closed loop with space state controller:
t = 0:1E-4:.5;
ss_cl = ss(Am-Bm*K,Bm*V,Cm,0,'Name','space state controller','InputName',mot.ssMdl.InputName,'OutputName',mot.ssMdl.OutputName);
[y,t,x]=lsim(ss_cl,V*u,t,xm0);
figure();plot(t,y);title('step on closed loop');
% *** observer controller ***
%
%observer poles-> 5 times farther left than system poles
if motid==1
op1=(p1*5);
op2=(p2*5);
if length(poles)>4
op3=(p3*5);
OP=[op1 op1' op2 op2' op3 op3'];
else
OP=[op1 op1' op2 op2'];
end
else
op1=(p1*2);
op2=(p2*2);
if length(poles)>4
op3=(p3*2);
op4=(p4*2);
op5=(p5*2);
op6=(p6*2);
OP=[op1 op1' op2 op2' op3 op3'];% op4 op4' op5 op5' op6 op6'];
else
OP=[op1 op1' op2 op2'];
end
end
L=place(Am',Cm',OP)';
%L=acker(A',C',OP)';
At = [ Am-Bm*K Bm*K
zeros(size(Am)) Am-L*Cm ];
Bt = [ Bm*V
zeros(size(Bm)) ];
Ct = [ Cm zeros(size(Cm)) ];
% step answer on closed loop with observer controller:
ss_o = ss(At,Bt,Ct,0,'Name','observer controller','InputName',{'desPos'},'OutputName',mot.ssMdl.OutputName);
figure();lsim(ss_o,ones(size(t)),t,[xm0 xm0]);title('step on closed loop with observer');
% *** disctrete observer controller ***
%
Ts=1/5000; % 5kHz
ss_od = c2d(ss_o,Ts);
ss_od .Name='discrete obsvr ctrl';
% step answer on closed loop with disctrete observer controller:
t = 0:Ts:.05;
figure();lsim(ss_od ,ones(size(t)),t,[xm0 xm0]);title('step on closed loop with observer discrete');
%plot all bode diagrams of desPos->actPos
figure();
h=bodeplot(ss_cl(3),ss_o(3),ss_od(3));
setoptions(h,'FreqUnits','Hz','Grid','on');legend('location','sw');
figure();
h=pzplot(ss_cl(3),ss_o(3),ss_od(3));
setoptions(h,'FreqUnits','Hz','Grid','on');legend('location','sw');
%calculate matrices for the simulink system
Ao=Am-L*Cm;
Bo=[Bm L];
Co=K;
Do=zeros(size(Co,1),size(Bo,2));
mdlName='observer';
open(mdlName);
%state space controller
ssc=struct();
for k=["Ts","Ap","Bp","Cp","Dp","Ao","Bo","Co","Do","V","K","L","ss_cl","ss_o","ss_od","numV","denV"]
ssc=setfield(ssc,k,eval(k));
end
end
%code snipplets from an example on youtube (see reference at top)
function SCRATCH()
A = [ 0 1 0
980 0 -2.8
0 0 -100 ];
B = [ 0
0
100 ];
C = [ 1 0 0 ];
poles = eig(A)
t = 0:0.01:2;
u = zeros(size(t));
x0 = [0.01 0 0];
sys = ss(A,B,C,0);
[y,t,x] = lsim(sys,u,t,x0);
plot(t,y)
title('Open-Loop Response to Non-Zero Initial Condition')
xlabel('Time (sec)')
ylabel('Ball Position (m)')
p1 = -10 + 10i;
p2 = -10 - 10i;
p3 = -50;
K = place(A,B,[p1 p2 p3]);
sys_cl = ss(A-B*K,B,C,0);
lsim(sys_cl,u,t,x0);
xlabel('Time (sec)')
ylabel('Ball Position (m)')
p1 = -20 + 20i;
p2 = -20 - 20i;
p3 = -100;
K = place(A,B,[p1 p2 p3]);
sys_cl = ss(A-B*K,B,C,0);
lsim(sys_cl,u,t,x0);
xlabel('Time (sec)')
ylabel('Ball Position (m)')
t = 0:0.01:2;
u = 0.001*ones(size(t));
sys_cl = ss(A-B*K,B,C,0);
lsim(sys_cl,u,t);
xlabel('Time (sec)')
ylabel('Ball Position (m)')
axis([0 2 -4E-6 0])
Nbar = rscale(sys,K)
lsim(sys_cl,Nbar*u,t)
title('Linear Simulation Results (with Nbar)')
xlabel('Time (sec)')
ylabel('Ball Position (m)')
axis([0 2 0 1.2*10^-3])
end