Why sum block outputs value half of the input?

Hello,

I am new to simulink and trying to understand why this system always gives the output half of the input.

If you calculate the the output

it should be 1 - 0 = 1

next step, 1 - 1 = 0

next step, 1 - 0 = 1

and so on.

How to understand the current behavior of the system?

[Roger J]

Looks like you have an algebraic loop. See the following

https://www.mathworks.com/matlabcentral/answers/95310-what-are-algebraic-loops-in-simulink-and-how-do-i-solve-them#answer_104662

To get the alternating 1 and zero, try adding a delay before the ”-” input on your adder.

[shubham aadhe]

Thank you Roger.

I got my concept cleared.

Answer 1

[Walter Roberson]

There is no implied delay between blocks, and you have configured a continuous solver.

Your system is equivalent to asking

solve(1-x==x)

which has a solution of 1/2

You need to break the algebraic loop, by using one of the methods of introducing a delay between the output of the difference and the time the difference gets fed back as input. Look in blogs.mathworks.com for the topic of breaking algebraic loops