My MSc research involved developing new techniques for collecting blood for wearable glucose monitoring applications. The thesis text and summary are publicly available from the University of Calgary.
Core concept of the main area of investigation: Shape memory alloy wires contract to pull a slider, which drives an L-shaped needle against one wall of a custom opening, causing the needle to rotate downwards.
The most sophisticated version of the slider-needle assembly: the L-shaped needle was embedded in a disposable plastic part, free to rotate between 15 and 90° relative to the main plane. The plastic part was fitted onto a metal slider, providing isolation and a reliable interface between single- and multi-use parts of the mechanism.