Abstract: A conveyor system incorporating a plurality of lift assemblies, wherein the lift assembly includes a platform for supporting an article during manufacture. A cylinder assembly is used for vertically supporting the platform and for moving the platform vertically between any one of a plurality of vertical height positions. A control system is used for actuating the cylinder assembly. The control system monitors the movement of the article along the assembly line, and includes predetermined height/position routines that are used to actuate the cylinder assembly and thereby move the platform vertically to a predetermined platform height corresponding to the location of the article on the line. In this way, the platform heights are selected to provide an ergonomic benefit in performing each operation.