states are the roll angle phi, the body velocities ub,vb,wb, and the angular rates p,q,r.
Accordingly, use modred to obtain a 7th-order model that only retains these states.
G7 = G;
xKeep = {...
'phi theta psi(1)'
'ub,vb,wb(1)'
'ub,vb,wb(2)'
'ub,vb,wb(3)'
'p,q,r(1)'
'p,q,r(2)'
'p,q,r(3)'};
[~,xElim] = setdiff(xG,xKeep);
for ct=1:40
G7(:,:,ct) = modred(G(:,:,ct),xElim,'truncate');
end
With these linearized models in hand, you can move to the task of tuning and scheduling
the flight control system gains. See “Angular Rate Control in the HL-20 Autopilot”
(Control System Toolbox) for Part 2 of this example.
See Also
More About
- “Angular Rate Control in the HL-20 Autopilot” (Control System Toolbox)
- “Model Gain-Scheduled Control Systems in Simulink” (Control System Toolbox)
11 Gain-Scheduled Controllers