Aircraft Longitudinal & Lateral/Directional Models & Modes (Phugoid, Short Period, Dutch Roll, etc.)

In this video we break apart the linear aircraft model into 2 separate linear models (the longitudinal model and the lateral/directional model). We show that at certain flight conditions, these models are decoupled and therefore can be treated/simulated independently. From these simplified models we investigate the characteristic modes of the aircraft (phugoid, short period, dutch roll, roll subsidence, spiral divergence, and heading modes). We show how to excited these modes and observe the response of the system to gain insight and intuition into how these modes affect the behavior of an aircraft.

Topics and timestamps:
0:00 – Introduction
8:25 – Similarity transformation to reorder states
19:53 – Decoupled systems
24:09 – Longitudinal aircraft model
30:46 – Exciting longitudinal modes with elevator doublet
36:19 – Exciting longitudinal modes with initial conditions
45:35 – Short period mode
50:25 – Phugoid mode
56:04 – Lateral/directional aircraft model
57:41 – Dutch roll mode
1:00:34 – Roll subsidence mode
1:01:36 – Spiral divergence mode
1:06:44 – Heading mode
1:09:09 – Conclusions

Lecture notes and code can be downloaded from https://github.com/clum/YouTube/tree/...

References/Prerequisites:
-A Nonlinear, 6 DOF Dynamic Model of an Aircraft: the Research Civil Aircraft Model (RCAM) (   • A Nonlinear, 6 DOF Dynamic Model of a...  )
-Building a Matlab/Simulink Model of an Aircraft: the Research Civil Aircraft Model (RCAM) (   • Building a Matlab/Simulink Model of a...  )
-Trimming a Model of a Dynamic System Using Numerical Optimization (   • Trimming a Model of a Dynamic System ...  )
-Trimming a Simulink Model Using the Linear Analysis Tool (   • Trimming a Simulink Model Using the L...  )
-Numerically Linearizing a Dynamic System (   • Numerically Linearizing a Dynamic System  )
-Linearizing a Simulink Model Using the Linear Analysis Tool and 'linmod (   • Linearizing a Simulink Model Using th...  )
-Similarity Transformation and Diagonalization (   • Similarity Transformation and Diagona...  )
-(Similarity Transformation of a Linear Dynamic System (   • Similarity Transformation of a Linear...  )
-Eigenvalues and Modes of Linear Systems (   • Eigenvalues and Modes of Linear Systems  )
-Translating Inputs, Outputs, and Initial Conditions Between Linear and Nonlinear Dynamic Systems (   • Translating Inputs, Outputs, and Init...  )
-Visualizing the State of a Simulink Aircraft Model Using X-Plane (   • Visualizing the State of a Simulink A...  )

All Flight Mechanics videos in a single playlist (   • Flight Mechanics  )

#FlightMechanics

All Control Theory videos in a single playlist (   • Control Theory  )

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