Portland State University. Department of Engineering and Applied Science
Pah I. Chen
Date of Award
Master of Science (M.S.) in Applied Science
1 online resource. Digitized photocopy of typescript.
Fluidic devices -- Design -- Data processing, Automatic control -- Mathematical models
This thesis presents the method of state diagram synthesis and the development of a computer program for designing fluidic sequential feedback • control circuits of the fundamental mode. A paper on state diagram synthesis was authored by Chen and Lee, presented in Detroit and published as ASME paper 73-WA/Flcs-2 in 1973. Hypothetical systems are illustrated by using series of events characterized by the piston positions of some double-acting pneumatic cylinders. In these systems , an action can only begin when the previous action has been completed. Every extension or retraction of a piston is memorized and manifested by a flip-flop element in the feedback circuit. If different combina- tions of control signals result from different combinations of feedback signals, the logic design is straightforward. Otherwise secondary variables are needed to differentiate between repeated appearances of some ambiguous input combinations. A secondary variable is obtained as the output of a fluidic flip-flop with set and reset inputs. When a sufficient number of secondary variables are obtained, they are combined with the feedback signals. Considerations of these variables and their associated logic complementary "don't-care" conditions leads to a set of simplified control equations. The complete process of the circuit design, using state diagram synthesis, has been programmed for a digital computer. After the control equations are obtained , one can take the signal transmission characteristics into account in order to build a hazard-free circuit.
Lee, Yau-Hwang, "Computer Aided Design for Fluidic Sequential Circuits of Fundamental Mode" (1975). Dissertations and Theses. Paper 2391.