Our inspiration to make ContacTrak was the many headlines and concerns over COVID-19 in schools that are reopening this fall. We wanted our app to make schools a safer environment for everyone in them.
What it does
Our app uses Core Bluetooth to keep track of the students that have been in contact with each other throughout the school hours. We store this data and make it exportable so you can send the data to a school administrator or to warn someone if you got COVID-19 and they could be at risk.
How we built it
We made our mobile app using Swift but the main functionality, the contact tracing, we built using Core Bluetooth. Core Bluetooth gives you a number called the RSSI, which is basically how strong the bluetooth signal is between two phones. Using this number, we calculated the distance between the phones and constantly checked if they were breaking social distancing.
Challenges we ran into
One of the main challenges that we ran into was the inaccuracy of both RSSI and multipeer connectivity. Our team started out by using RSSI, but realized that it wasnt that accurate so we decided to switch to using multipeer connectivity. After trying multipeer connectivity, we realized it got the distance between devices through latitude and longitude coordinates which are not that accurate on a small scale. From here, we decided to go back to using RSSI and learned that one of the factors that might have been affecting the accuracy of it was the orientation of the phones. After fixing this problem, we were able to get our contact tracing app to be a lot more accurate.
Accomplishments that we're proud of
We are proud of how we were able to use Apple’s CoreBluetooth API to create our own technology. We are also very proud of how we built a contact tracing app that is accurate to the meter, as most other projects use coordinates, which are highly inaccurate in a school setting.
What we learned
Through the making of this project, we learned a lot about RSSI, or Received Signal Strength Indicator, and the factors that can affect it such as phone orientation. In addition, we learned more about multipeer connectivity and how it uses latitude and longitude coordinates to get the distance between phones. Related to this, we learned about how latitude and longitude is inaccurate on a smaller scale (like when checking if someone is within 6 feet of you).
What's next for ContacTrak
Some ideas are: An Apple Watch App - This could allow for easier contact tracing because you wouldn't need the app on your phone if implemented correctly Indoor Mapping - In the future we could provide indoor mapping of schools, to see where exactly the student was when they made that contact with someone else Database Storage - We can store all of the accounts, details, and data that the app collects in a database Web App - To accompany this iOS App we could've also made a web app, that would show this data on the screen for a specific account. This would be only possible if we utilized database storage