Scissor lift?

[artdutra04]

It's generally very difficult to make scissor lifts "work", and when they do work they have many poor mechanical/kinematic qualities. They need to be light-weight to work decently, but it takes a lot of added weight to make them robust enough to actually work. It also takes a tremendous amount of force to start lifting them, as there is a very poor transmission angle.

Regular arms, four-bar arms, and forklift/telescoping elevators are all mechanically preferable to scissor lifts.