A flow system device used for testingcreating fluid flow. A splitter region, associated with a booster compressor of the turbofan engine, is identified. The amount of communication data and the amount of routing paths between components are reduced, thus decreasing system reaction time and heat generated, allowing controls to be installed on smaller circuits, such as ASIC, and the arrays to be placed closer together. The rotary body joining tool has a small-diameter tip portion and a larger diameter portion. A handheld printer according to the present teachings includes a navigation subsystem that tracks a motion of the handheld printer with respect to a printing surface and a print head controller that causes a print head to fire ink drops onto the printing surface in response to the motion and in response to an image contained in an image buffer.