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LCP MEMS sensor and package design for CPAP devices
thesisposted on 2022-03-28, 12:27 authored by William Thorby
The ability to accurately measure fluid flow velocity and direction are important measures for data collection in a variety of industries including environmental science, biotechnology, aerospace and emergency response organisations. As a result of extensive research and development into micro-electromechanical systems (MEMS), a low-cost, miniaturised, biomimetic piezoresistive sensor inspired by the lateral line sensory system has been developed to be more durable, flexible, robust to harsh environments, more cost effective to manufacture and more sensitive than traditional MEMS flow sensors on the market today. This thesis aims to design, simulate, assemble and test different packaging designs and configurations for the LCP sensor in order to determine its usability and performance in air flow monitoring within the medical industry, by comparing the air flow velocity detection capabilities of the system with a commercially available sensor inside a Continuous Positive Airway Pressure (CPAP) device, used to treat patients with sleep apnea. It is demonstrated in this thesis that the pressure sensor configuration and flow sensor configuration outperform the commercial sensor in low flow velocity detection, reduced signal noise and the ability to show a measurable voltage change per ILPM change in flow rate, but there is a lack of response time due to the mechanical nature of the sensor. Various future work suggestions are recommended, with preliminary testing of the flow sensor in a nasal mask completed.