Hello,

I am VERY new to Simulink, I am trying to model the Mackey-Glass equation. 

dx(t)/dt = 0.2 ___x(t - tau)____ - 0.1x(t)      where x(0) = 2.5  and tau=15 
                      1 - x^10 (t- tau)

I know that I must take the derivative of y, integrate to generate x . So everything is delayed tau seconds I think I must use the  transport delay block.

But how do I arrange the blocks so that it all works?  And how do i do x^10 in Simulink?

Blocks I am using: Constant (1)
                          Step
                          Add (+ + -)
                          Integrator
                          Gain (2 and 0.1)
                          Transport Delay
                           Scope
                          Workspace

Any help is very appreciated.

"Antonio0878 Manzoni" <antonio040778@gmail.com> wrote in message 
news:ibsooo$6r5$1@fred.mathworks.com...
> Hello,
>
> I am VERY new to Simulink, I am trying to model the Mackey-Glass equation.
> dx(t)/dt = 0.2 ___x(t - tau)____ - 0.1x(t)      where x(0) = 2.5  and 
> tau=15 1 - x^10 (t- tau)
>
> I know that I must take the derivative of y, integrate to generate x . So 
> everything is delayed tau seconds I think I must use the  transport delay 
> block.
>
> But how do I arrange the blocks so that it all works?  And how do i do 
> x^10 in Simulink?

The simplest way I can think of:  draw a line in your model and label it 
dx/dt.  Now pass that through an Integrator block and label the output line 
with the mathematical expression it represents.  [Hint:  what do you get if 
you integrate dx/dt?]  Then use that in conjunction with the other blocks to 
build up the right side of your differential equation, which you then feed 
back to become the source of that first line you drew.  As for your second 
question:  look at the Math Functions block in the Math Operations library.

If you still need help, put your Simulink model on some file hosting site 
and include a link to it in your next newsgroup posting.  [Please don't 
email it to me directly.]

-- 
Steve Lord
slord@mathworks.com
To contact Technical Support use the Contact Us link on 
http://www.mathworks.com