Design Case Studies

Computing Open-Loop Eigenvalues

Compute the open-loop eigenvalues and plot them in the -plane.

• damp(sys)
  
  Eigenvalue                    Damping         Freq. (rad/s)  
                                                           
   -7.28e-003                  1.00e+000      7.28e-003    
   -5.63e-001                  1.00e+000      5.63e-001    
   -3.29e-002 + 9.47e-001i     3.48e-002      9.47e-001    
   -3.29e-002 - 9.47e-001i     3.48e-002      9.47e-001 
  
  pzmap(sys)
  
  
  
  

This model has one pair of lightly damped poles. They correspond to what is called the "Dutch roll mode."

Suppose you want to design a compensator that increases the damping of these poles, so that the resulting complex poles have a damping ratio with natural frequency rad/sec. You can do this using the Control System toolbox analysis tools.

Yaw Damper for a 747 Jet Transport

Open-Loop Analysis