2 # $Id: controls.dem,v 1.3 1999/10/17 19:16:58 lhecking Exp $
4 # warning: this demo is SLOW on PCs without math coprocessors!
6 # From _Automatic_Control_Systems_, fourth ed., figure 6-14
7 # transient response of a second-order system to a unit step input function
9 damp(t) = exp(-s*wn*t)/sqrt(1.0-s*s)
10 per(t) = sin(wn*sqrt(1.0-s**2)*t - atan(-sqrt(1.0-s**2)/s))
11 c(t) = 1-damp(t)*per(t)
13 # wn is natural undamped frequency
22 # plot c(t) for several different damping factors s
24 plot s=.1,c(t),s=.3,c(t),s=.5,c(t),s=.7,c(t),s=.9,c(t),s=1.0,c(t),s=1.5,c(t),s=2.0,c(t)
25 pause -1 "Hit return to continue"