This is the physical staircase that users will step on. There will be a moving stair tread
which rebounds to its raised position via several springs under the moving tread plate.
The tread plate will be hinged in the back to restrict the tread to one degree of motion.
The tread will be limited in its vertical travel to about a half inch. We will be able to
adjust the vertical travel of the stair via screw with an adjustable wing nut.