Mosfet not working

I use a Mosfet(IRL540 N-channel) to control electrical grounding, I want to simulate touch screen.
http://www.fpl2012.org/Presentations/PHD7.pdf, It not works.

But I use the mosfet to control LED, It works fine.

Why?

I want to simulate touch screen.

I think you mean sTIMULATE touch screen.
Post a schematic of your circuit and a link for the touch screen.

schematic

You shouldn't use a led without a resistor.

Just test the Mosfet, I can control the led to close or open, but I can't control the touch

You haven't posted anything useful to tell us what your touchscreen is. Your link above is useless. We need a vendor link and a photo of the touchscreen. Without that we can't even begin to help you.