How to represent uncertain transport delays

Hi all,

I would like to have a dynamic system with uncertain transport delay. Is there any straightforward way to do it using Control System and Robust Control toolboxes?

I was able to create either a system with uncertain poles and zeros, or a system with constant ('certain') time delay.

 T = ureal('time',1); G_unc = tf(1,[T 1])
 Gdel = ss([],[],[],1,'OutputDelay',1)

However, the two things together did not work:

 ss([],[],[],1,'OutputDelay',T)

gave the following error (due to ltipack.matchType)

 Error using StaticModel/ss (line 107)
 Undefined function or variable "A".

and

 ss(T,T,T,T,'OutputDelay',T)

resulted in

 Error using StaticModel/ss (line 107)
 The value of the "OutputDelay" property must be a vector of nonnegative numbers.

Am I missing something? Any help would be appreciated..

Thanks, Ondrej

Answer 1

[Arkadiy Turevskiy]

Hi,

Unfortunately, modeling of uncertain transport delays is not currently supported.

Arkadiy

[Ondrej Holub]

Arkadiy,

Thank you for the reply. Even though I sampled the delays on my own, it would be a nice addition to the current functionality.

Regards, Ondrej

[Arkadiy Turevskiy]

Thank you for your suggestion.

You might be interested in taking a look at our recent webinar on modeling time-delay systems. It covers robustness analysis for uncertainty in time delay value.

Arkadiy

[Boris Konig]

Unfortunately, the link does not work anymore. Is the webinar still available somehow?