Can anyone explain this building technique?

[TravisH44]

Hi All,

I recently came across this incredible piano MOC that LEGO picked up to produce and among all of its dazzling features is an adjustable bench. I'm trying to learn as many building techniques as I can but I cannot figure out how this is done. Can anyone explain? Link below:

 

[coinoperator]

WOW

No idea but this is stunning.

[Mylenium]

A simple scissor mechanism most likely - two liftarms jacking open and or closing based on a corkscrew wheel.

Mylenium