Week 06

Routh-Hurwitz Stability

I follow the saved course materials and calculations from modeling through stability, root locus, and frequency response.

Automatic Control course visual
Course visual for this study sequence.

What I connect in this unit

A Routh-Hurwitz array determines the number of right-half-plane poles directly from the characteristic-polynomial coefficients. Sign changes in the first column reveal instability, and a symbolic gain turns the same conditions into an admissible gain interval.

Concept map

  1. Characteristic equation
  2. Routh arrays
  3. Right-half-plane poles
  4. Gain range

Technical anchor

Place alternating coefficients of a_n s^n+...+a_0=0 in the first two rows and complete the first column. Solve all first-column positivity inequalities together to obtain the gain condition.

How I review it

Treat a zero leading element separately from an all-zero row, and use the auxiliary polynomial to check for imaginary-axis roots at a boundary gain.

Connection to the full course

Unit 6 of 12. Unit numbers organize the concepts found in the materials and do not reproduce an attendance schedule.

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