In this study, a new HMS (Health Monitoring System) device is developed for diabetic patient. This device mainly
consists of I) 3D blood vessel searching unit and II) automatic blood glucose measurement (ABGM) unit. This device
has features such as 1)3D blood vessel location search 2) laptop type, 3) puncturing a blood vessel by using a minimally
invasive micro-needle, 4) very little blood sampling (10μl), and 5) automatic blood extraction and blood glucose
measurement. In this study, ABGM unit is described in detail. It employs a syringe type's blood extraction mechanism
because of its high accuracy. And it consists of the syringe component and the driving component. The syringe
component consists of a syringe itself, a piston, a magnet, a ratchet and a micro-needle whose inner diameter is about
80μm. And the syringe component is disposable. The driving component consists of body parts, a linear stepping motor,
a glucose enzyme sensor and a slider for accurate positioning control. The driving component has the all-in-one
mechanism with a glucose enzyme sensor for compact size and stable blood transfer. On designing, required thrust force
to drive the slider is designed to be greater than the value of the blood extraction force. Further, only one linear stepping
motor is employed for blood extraction and transportation processes. The experimental result showed more than 80% of
volume ratio under the piston speed 2.4mm/s. Further, the blood glucose was measured successfully by using the
prototype unit. Finally, the availability of our ABGM unit was confirmed.
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