US Patent 8631529 Operable step

A step assembly provides access between a lift platform and an alighting surface. The step assembly includes a tread and a panel rotatably connected to the tread about a first axis. An actuator assembly is operably coupled to the panel to selectively move the step assembly between a raised position and a lowered position. In the raised position, the tread is substantially horizontal, and the panel is orthogonal to the tread. In the lowered position, the tread and the panel are substantially parallel and form a predetermined angle with respect to a horizontal plane.