Optimization of a Piezoelectric Micropump Actuator for Medical Application in Glaucoma and Phthisis Therapy

摘要

The goal in this project was to design a micropump that enables a therapy for the eye diseases glaucoma and phthisis. By adding or removing eye liquid with an implant system, the intraocular pressure is to be manipulated to a healthy level. The main challenges of the implant are to fulfill the fluidic requirements as well as minimize the overall system size to fit within the eye cavity. A piezoelectric micropump actuator has been optimized to address the requirements of flow rates ＞6μl/min and a pressure ability of ＞120kPa while limiting the operating voltage to 150V and providing good energy efficiency to minimize the implant size. A Mathematica simulation has been performed to balance different performance values like the inverse proportional maximum pressure ability and flowrate. Driving the piezo at a pump frequency of 25Hz the estimated real flow rate will be around 110μl/min. Applying the necessary average flow rate of 2μl/min for glaucoma patients the system only needs to be active for less than half an hour per day, making a treatment adjusted by a physician feasible.