Simulink Control Design™ - MathWorks

• Normal velocity w (m/s)


• Pitch rate q (deg/s)


• Pitch angle theta (deg)


• Lateral velocity v (m/s)


• Roll rate p (deg/s)


• Roll angle phi (deg)


• Yaw rate r (deg/s)

The control system of the model has two feedback loops. The inner loop provides static

output feedback for stability augmentation and decoupling, represented in the model by

the gain block SOF. The outer loop has a PI controller for each of the three attitude

angles. The controller generates commands ds,dc,dT in degrees for the longitudinal

cyclic, lateral cyclic, and tail rotor collective using measurements of theta, phi, p, q,

and r. This loop provides the desired setpoint tracking for the three angles.

This example uses these control objectives:

• Track setpoint changes in theta, phi, and r with zero steady-state error, rise times of
  about 2 seconds, minimal overshoot, and minimal cross-coupling.


• Limit the control bandwidth to guard against neglected high-frequency rotor dynamics
  and measurement noise. (The model contains low-pass filters that partially enforce this
  objective.)


• Provide strong multivariable gain and phase margins. (Multivariable margins measure
  robustness to simultaneous gain or phase variations at the plant inputs and outputs.
  See the diskmargin reference page for details.)

Set Up the Model for Tuning

Using Control System Tuner, you can jointly tune the inner and outer loops to meet all the

design requirements. To set up the model for tuning, open the app and specify which

blocks of the Simulink model you want to tune.

In the Simulink model window, in the Analysis menu, select Control Design > Control

System Tuner.

13 Control System Tuning Examples