Simulink Control Design™ - MathWorks

Tuning of a Two-Loop Autopilot

This example shows how to use Simulink Control Design to tune a two-loop autopilot

controlling the pitch rate and vertical acceleration of an airframe.

Model of Airframe Autopilot

The airframe dynamics and the autopilot are modeled in Simulink.

open_system('rct_airframe1')

The autopilot consists of two cascaded loops. The inner loop controls the pitch rate q, and

the outer loop controls the vertical acceleration az in response to the pilot stick command

azref. In this architecture, the tunable elements include the PI controller gains ("az

Control" block) and the pitch-rate gain ("q Gain" block). The autopilot must be tuned to

respond to a step command azref in about 1 second with minimal overshoot. In this

example, we tune the autopilot gains for one flight condition corresponding to zero

incidence and a speed of 984 m/s.

Tuning of a Two-Loop Autopilot