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I've Built Myself An Artificial Pancreas!

@catapillar, the issue with the glucagon version of an AP is that the available glucagon now is only stable for a day. Bigfoot has been working with manufacturers who are trying to extend this, and the way openAPS works, if a dual chamber pump was available, it could apply glucagon to counter impending lows.
 
tim2000s said:
@catapillar, the issue with the glucagon version of an AP is that the available glucagon now is only stable for a day. Bigfoot has been working with manufacturers who are trying to extend this, and the way openAPS works, if a dual chamber pump was available, it could apply glucagon to counter impending lows.
Click to expand...

Yep, beta bionics with the bionic pancreas has all the hardware and software available to do dual chamber AP, but not stable glucagon and glucagon isn't licenced in the us (where it would be trialled) for micro bolusing. So it's not imminently available. Which is sad because I think Ed Damiano wanted to be able to send his son off to college with a running bionic pancreas, and he must be starting college right now. I wonder if they are just swapping out the glucagon chamber daily? But it's on my wish list. I can be ambitious for my wish list. Top of the list is a cure, next is a closed loop dual chamber AP. I'm demanding :)
 
So after rather a lot more hacking than I expected to have to do to get the 640G data into the oref0 algoriithm effectively and offline, I have a fully looping system that's not dependent on a network connection to make a decision. If you aren't using the straightforward, well followed path, this can be a right PIA, but it's very satisfying to see it doing what it's supposed to be when you get there! This is this morning after a sensor change and a very proteiny breakfast.

Loop_zpsrcgtyx4y.jpg
 
So taking this a step further, I finally got around to the Loop app. This is an evolution of the openAPS work , built by someone else, but along very similar guidelines, and in my opinion is what all Hybrid Closed Loop manufacturers should be considering.

Loop is an iPhone app that interfaces with a pump via the RileyLink (a Bluetooth to 900MHz converter) and uses Dexcom G5 on board the phone for CG data). It has similar features to OpenAPS, but as it all runs on your iPhone, requires a lot less carrying.

IMG_0182_zpsdpexcsnx.jpg


As you can see in the picture below, Loop has a console showing the current sensor glucose level, the predicted level and also carb and insulin profiles. It also gives you a nice image of basal rate changes. The other feature that's rather cool is the "bolus" feature that works from the Apple Watch or the Phone, and if using the phone, requires the use of the Touch security. Without your fingerprint, no bolus.

IMG_0181_zps6kgam12y.png


What I'd like to see from all the guys trying to commercially produce products like this is that they looked at what we as a community have built and then worked out how they could build a commercial product that fits into that model. Our stuff looks like this because we want it to work for us, in our workflows.

So an app on the phone and the pump and CGM all combining either through that or through a single pump device with a connected phone app has to be the right way to go!
 
Hi Tim

How does it manage a negative insulin delivery, surely this can only be zero or positive ? 3am 6am ?

But looks great BTW.
 
When it gives you a negative number, it basically sets a basal rate of 0. The purpose of the negative value is part of the prediction of future glucose levels.

Both Loop and openAPS are fantastic by the way!
 
Ok understood, thanks for that.

In hindsight I wish I'd gone down the Medtronic route 6 months ago, but in another 3 years it will all change again. Great to see you're doing so well with it.
 
I thought it might be interesting to show the outcome of one whole month of running on a combination of Loop and OpenAPS. This is the Ambulatory Glucose Profile and the Monthly Stats for a month with a Hybrid Closed Loop. Throughout this period, I've not been low carbing particularly and there have been cakes, toast and just maybe the rather too frequent chocolate. It makes for interesting reading.

What's interesting for me when compared to the 80 days from April through to mid-June that I wore CGM whilst Sugar Surfing on the pump is the similarity of the stats. The major difference between the two is the amount of effort required to get to the same results.

Percentile.JPG Distribution.JPG

For comparison, I present 80 days of data from the beginning of April through to Mid-June which was all on a pump, but using sugar surfing techniques, rather than having a hybrid closed loop do it for me.

Sugar Surfing 80 AGP.JPG SUgar Surfing 80 Dist.JPG
 
tim2000s said:
I can't find the "Evil Stare" emoji.....
Click to expand...
My laughing face one never worked from my 3rd party android keyboard - so a grinning face will do.

Nice BG trends, etc btw. Man I hope I can get approved for a pump! I think playing around with all this available software will open so many doors!
 
So.... I have finally gotten my OpenAPS rig down to a one box solution that works with the glucose monitoring on the pump. It's now highly portable, completely offline capable, charges wirelessly and I monitor it from a Pebble watch on my wrist. It looks a little something like this:

IMG_1336.jpg
 
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