The strip connector has been one of the main obstacles in designing a Universal Glucometer. Glucose test strips all seem to have slightly different dimensions, as well as spacing and ordering of contacts.
My original vision was to use a single connector/port to insert test strips into. My idea was to use a connector with multiple contacts and when the strip was selected from the menu the contacts specific to each strip would be enabled (and unused contacts disabled).
To accomplish this I, initially, thought that I
would either need a micro-controller with enough pins available for
this or I would need to use a parallel to serial converter to select pins. Of course, using a shift register,
(which would only work if all the pins also went through ADC's to convert the analog signal to digital information.
I decided that this approach would add to many parts to the design – making it more expensive and more difficult to put together.
Thankfully, I kept the suggestion by netrunner in the back of my mind – seems to be the best approach for now. This approach involves adapters that plug into the meter that match the contacts and dimensions of different strips and adapt them to the Universal Glucometer strip reader jack/connector.
Currently this involves 3D Printing housings for strip connectors, Copper clad board, 90 degree male headers (0.1” standard spacing), and 22 gauge hook up wire.
Evolution of the design:
Accu-Check Aviva Strip connector salvaged from meter and adapted to breakout board for testing on breadboard (total of 8 contacts). This was the first connector I tried using (since it seemed adaptable to different strips by using different contacts).
This connector I pulled out of a xxx test strip reader. Before I could test this with actual strips I broke it while trying to add mounting holes.
Hand Milled from scrap acrylic - contacts are just 22 gauge wire threaded through. This basic setup worked fine with ReliOn test strips (not very elegant but functional)
This is the type of connector I'm finally settling on - connects easily to the Universal Glucometer board, easy to adapt to different strip dimensions and pinouts.