Please complete this documentation where necessary since they were put together retrospectively from some disconnected technical notes I had (we realised half the way that nobody was documenting the session),
Open-source Digital Microfluidic (DMF) automation system, the dropbot
Participants (I remember):
Joel Murphy
Dulce Alarcón
Jean Pierre Tincopa
…(pelase add)
A group of about 10 people from different backgrounds attended this session, mostly men except from Dulce (from Peru).
This device can manipulate discrete droplets on a surface of electrodes covered by a hydrophobic layer.
Ryan started by explaining the design and functioning basis of the dropbot. Particularly, the composition of base electrode, insulation/hydrophobic layer, sample (drops) and a top layer consisting of GND, basically.
He proceeded to open the device and pass around internal boards to close inspection. He started from the top board containing all the circuitry for logic control and V conversion. The device uses 110V but is powered from 12V. Ryan explained the basic circuitry that allows the 12V—>110V conversion by using a chip and a special transistor to ramp up the voltage. He also explained the use of some transistors (I didn´t catch in what part) with very low resistance (micro-ohms) that guarantees less heat generation from high currents. He also described the use of a teensy for logic control (e.g. temperature monitoring inside the whole device).
He also explained the use of reversible fuses (PTC) for over-current protection
The metal case was ordered from polycase. Please add images!