Simulink Control Design™ - MathWorks

trim values of the deflections da,de,dr depend on the airframe orientation relative to the

wind. This orientation is characterized by the angle-of-attack (AoA) alpha and the sideslip

angle (AoS) beta.

With the operspec and findop functions, you can efficiently compute the trim

deflections over a grid of (alpha,beta) values covering the operating range of the vehicle.

Here we trim the model for 8 values of alpha ranging from -10 to 25 degrees, and 5

values of beta ranging from -10 to +10 degrees. The nominal altitude and speed are set to

10,000 feet and Mach 0.6.

d2r = pi/180; % degrees to radians

m2ft = 3.28084; % meter to feet

Altitude = 10000/m2ft; % Nominal altitude

Mach = 0.6; % Nominal Mach

alpha_vec = -10:5:25; % Alpha Range

beta_vec = -10:5:10; % Beta Range

[alpha,beta] = ndgrid(alpha_vec,beta_vec); % (Alpha,Beta) grid

Use operspec to create an array of operating point specifications.

opspec = operspec('csthl20_trim',size(alpha));

opspec(1)

11 Gain-Scheduled Controllers