[EricH]

Originally Posted by sandbag747

We don't even know how to move the segments if we tried that, how would you power it? My thought was pneumatic but we need it shorter thank the full length

Use a shorter pneumatic piston. The only restriction is that the piston (cylinder) be rated to 125 psi.
Also, look at some of 254's cable-powered lifts, for example in 2007. That takes a motor, a winch, and some cable or rope, along with pulleys. A little more work, perhaps, but infinite positions within the range of motion.