Dynamics & Control · Lab

First-Order System Lab

G(s) = K / (τs + 1). Read the same first-order system in the time domain or in the frequency domain: response and metrics, or Bode magnitude and phase with the corner frequency and bandwidth.

The same K/(τs + 1), seen as a response in time or as magnitude and phase against frequency.

System

1
1

Equivalent model

K
1
τ
1 s

G(s) = 1 / (s + 1)

The plotted curve is the total response: zero-input decay from y(0) plus the zero-state response to u(t).

Excitation

Excitation u(t)

Characteristics

Pole-1
DC gain G(0)1
Corner frequency1 rad/s
Time to 63.2%1 s
Rise time (10%–90%)2.197 s
Settling time (2%)4 s
Settling time (5%)3 s

Continue with this system

The current model travels with the link; nothing is re-entered and nothing opens on its own.

A first-order lag has no second-order continuation: nothing here maps onto ωn and ζ, so none is offered.

Response y(t)

Time view
output solid · input dashed grey · horizon 7 s

Measured response metrics

Final value y∞1
Peak value0.9991
Peak time7 s
Percent overshoot0 %
Settling time (2%)3.912 s
Settling time (5%)3 s
Rise time (10%–90%)2.197 s

Pole–zero map

poles = × · zeros = ○ · dashed line = imaginary axis
Numeric poles and zeros
RootRe(s)Im(s)Multiplicity
Pole ×-101

What this Lab models

The single-pole lag G(s) = K/(τs + 1): its time response to standard inputs, its pole and corner frequency, and its magnitude/phase against frequency — the same K and τ throughout.

Related calculations