It's so simple! you just need to study slotine's applied nonlinear control book, you will find out how to choose integral sliding surface and you can develop it to any system.

if the upper bound of uncertainty in your system is unknown you can use adaptive control theory to estimate uncertainty bound.

Thanks brother.

Dear Anteneh,

You can go through the book attached below. It is very simple and very helpful book on different SMC techniques with simulation example codes.

Follow Edwards and Spurgeon Book to understand sliding mode control and the method to design the sliding surface.

You can use adaptive sliding mode control to deal with uncertainty bound.

Assuming you have model of robotic arm, you need to define integral sliding mode surface as per standard literature.. then you need to show states on the surface converge to origin. Good thing about integral smc is there is no reaching time.

You can also watch my YouTube lectures on my channel yasiramir

For further discussion email.

[email protected]