An instrumented navigation system for aiding a towboat and barge configuration in the entry and traversal of a lock located on a waterway or for navigation around other structures, such as bridge piers or docks. The first region may be different from the second region, and the first and second virtual keyboards may display a substantially identical set of virtual keys. The engagement protrusion is provided to an outer surface of each lock piece. A first valve is in fluid communication with the first infusate reservoir and an inlet of the accumulator, and a second valve is in fluid communication with the second infusate reservoir and an inlet of the accumulator. The first device may modify the tuple information so as to identify the desired core when used with the hash key of the second device.