User`s guide

Time Delays
2-51
Note that the 0.1 second delay is on the input in the first model, and on the
output in the second model.
InputDelay and OutputDelay Properties
When the state trajectory is of interest, you should use the InputDelay and
OutputDelay
properties to distinguish between delays on the inputs and
delays on t he outputs in state-space models. For example, you can accurately
specify the two models above by
M1 = ss(–1,1,1,0,'inputdelay',0.1)
M2 = ss(–1,1,1,0,'outputdelay',0.1)
In the MIMO case, you can specify a different delay for each input (or output)
channel by a ssigning a vector value to
InputDelay (or OutputDelay).For
example,
sys = ss(A,[B1 B2],[C1;C2],[D11 D12;D21 D22])
sys.inputdelay = [0.1 0]
sys.outputdelay = [0.2 0.3]
creates the two-input, two-output model
You can also use the
InputDelay and OutputDelay properties to conveniently
specify input or output delays in TF, ZPK, or FRD models. For example, you
can create the transfer function
by typing
s = tf('s');
H = [1/s ; 2/(s+1)]; % rational part
H.inputdelay = 0.1
x
·
t() Ax t() B
1
u
1
t 0.1–()+ B
2
u
2
t()+=
y
1
t 0.2+()C
1
xt() D
11
u
1
t 0.1–()D
12
u
2
t()++=
y
2
t0.3+()C
2
xt() D
21
u
1
t 0.1–()D
22
u
2
t()++=
Hs()
1
s
---
2
s 1+
------------
= e
0.1s–