A hydraulic cylinder (assembly of piston rod and cylinder burrel) is in the main assembly, such that the hydraulic cylinder is subassembly. 

How may I change the stroke of the piston rod in the main assembly by manipulating the constraint in the subassembly (i.e constraint between th barrel and piston rod)?

I reffer to the Autodesk Inventor Adaptive - Drive Constraints. 

Creation of multiple configurations