# Bode, Nyquist, and Nichols Diagrams of Second-Order Systems

Bode, Nyquist, and Nichols Diagrams of Second-Order Systems

Consider a second-order system given by the transfer function:

G(s)=+2ζτs+1

K

p

2

τ

2

s

where is the damping coefficient, is the response time, and is the process steady-state gain.

ζ

τ

K

p

This Demonstration plots the Bode, Nyquist, and Nichols diagrams for user-set values of the parameters , , and . Different behaviors are observed for (underdamped or oscillating system), (critically damped system), and (overdamped system).

ζ

K

p

τ

0≤ζ<1

ζ=1

ζ>1