A micropump is a small device that can precisely deliver a tiny amount of fluid. Micropumps are widely used in microfluidic systems such as micro-cooling systems, fuel cells, and biomedical analysis systems. However, many micropumps are expensive and not reliable due to their design and fabrication processes. The objective of this work is the development of a micropump that can satisfy most common application requirements, such as the delivery of fluid at a controllable flow rate at a specified pressure, low power consumption, biocompatibility, compactness, reliability, and durability. In order to achieve this objective, extensive application requirements were considered systematically and transferred to design requirements during the concept design stage of the micropump design.

This thesis presents a novel design of a micropump system which can be fabricated using micromilling and microinjection molding technology. The micropump is driven by a commercially available PZT actuator and whose backflow is controlled by using flap valves. It has only 4 components, the PZT actuator, a top and bottom housing, and a valve plate. The overall size of the micropump is 30mm x 25mm x 6mm. A rational design of the micropump was achieved by using design methodologies and engineering analysis such as concept scoring, axiomatic design, design for manufacturing and assembly (DFMA), multiphysics finite element analysis (FEA), and fatigue analysis. The micropump design was also prototyped and tested to verify the proposed manufacturing process and the performance. The maximum flow rate obtained is 5.2 ml/min and the maximum pressure obtained is 13.4 kPa.

The contributions of this work include developing an axiomatic design method for concept selection, incorporating novel micropump design features, examining the application of DFMA to the detailed design of micro components and assemblies, applying engineering analysis for modeling of PZT actuators, fatigue of the valve and flow characteristics, confirming that micro-components can be effectively prototyped using micro-machining processes, and verifying the performance through testing.