What is a closed loop system with AAPS?
AAPS is an app that acts as an artificial pancreas system (APS) on an Android smartphone. What is an artificial pancreas system? It is a software program that aims to do what a living pancreas does: keep blood sugar levels within healthy limits automatically.
An APS can’t do the job as well as a biological pancreas does, but it can make type 1 diabetes easier to manage using devices that are commercially available and software that is simple and safe. Those devices include a continuous glucose monitor (CGM) to tell AAPS about your blood sugar levels and an insulin pump which AAPS controls to deliver appropriate doses of insulin. The app communicates with those devices via bluetooth. It makes its dosing calculations using an algorithm, or set of rules, developed for another artificial pancreas system, called OpenAPS, which has thousands of users and has accumulated millions of hours of use.
A note of caution: AAPS is not regulated by any medical authority in any country. Using AAPS is essentially carrying out a medical experiment on yourself. Setting up the system requires determination and technical knowledge. If you don’t have the technical know-how at the beginning, you will by the end. All the information you need can be found in these documents, elsewhere online, or from others who have already done it – you can ask them in Facebook groups or other forums. Many people have successfully built AAPS and are now using it entirely safely, but it is essential that every user:
Builds the system themselves so that they thoroughly understand how it works
Adjusts its individual dosage algorithm with his or her diabetes team to work nearly perfect
Maintains and monitors the system to ensure it is working properly
Disclaimer and Warning
All information, thought, and code described here is intended for informational and educational purposes only. Nightscout currently makes no attempt at HIPAA privacy compliance. Use Nightscout and AAPS at your own risk, and do not use the information or code to make medical decisions.
Use of code from github.com is without warranty or formal support of any kind. Please review this repository’s LICENSE for details.
All product and company names, trademarks, servicemarks, registered trademarks, and registered servicemarks are the property of their respective holders. Their use is for information purposes and does not imply any affiliation with or endorsement by them.
Please note - this project has no association with and is not endorsed by: SOOIL, Dexcom, Accu-Chek, Roche Diabetes Care, Insulet or Medtronic.
If you’re ready for the challenge, please read on.
Primary goals behind AAPS
An app with safety built in. To read about the safety features of the algorithms, known as oref0 and oref1, click here (https://openaps.org/reference-design/)
An all-in-one app for managing type 1 diabetes with an artificial pancreas and Nightscout
An app to which users can easily add or remove modules as needed
An app with different versions for specific locations and languages.
An app which can be used in open- and closed-loop mode
An app that is totally transparent: users can input parameters, see results, and make the final decision
An app which is independent of particular pump drivers and contains a “virtual pump” so users can safely experiment before using it on themselves
An app closely integrated with Nightscout
An app in which the user is in control of safety constraints
How to start
Of course, all of this content here is very important, but can be in the beginning quite confusing. A good orientation is given by the Module Overview and the Objectives.