Burton, Richard T.2004-08-312013-01-042005-08-312013-01-042004-082004-08-30August 200http://hdl.handle.net/10388/etd-08312004-100306This thesis proposes a new type of hydraulic valve: an adjustable-ratio flow divider. This valve attempts to split one input flow into two output flows in a predetermined ratio, independent of load pressure or total flow. The valve uses a two dimensional structure to form a two-stage valve with only one moving part; the pilot stage uses the spool s rotary position, and the main stage uses its linear position. This arrangement allows for a cheaper, simpler valve with smaller volumes (translating into faster response). The ratio of outlet flows can be set on the fly by the angular position of the spool, driven by a stepper motor or other low-power input. In order to evaluate the initial feasibility of the concept, steady state and dynamic models were developed and the effects of the physical parameters were studied. Two non-linear non-derivative multiobjective optimization strategies were used to determine the optimum parameters for a prototype. Finally, the prototype s performance was experimentally examined and appears to work as expected.en-UShydraulicflow controlflow dividerfluid powervalvehydraulicsAn adjustable-ratio flow dividing hydraulic valvetext