What will help me keep the structure at the same height? (People Playground)

Need help. What will help me keep the structure at the same height? For example: I have a platform at a height let's say two blocks from the ground. And I want to start the mechanism from it. I need it to be able to move right or left without losing altitude. I've already tried the Hover Truster, but it loses altitude until it almost hits the ground. What to do?