Cross University Collaboration: Asynchronous Contact Tracing with Smartphone Sensors.

Asynchronous contact tracing with smartphone sensors is an exciting cross-university collaboration. Dr. Ryan Southall from the School of Architecture and Design participates in this venture led by Dr. Khuong An Nguyen (University of Brighton) and Dr. Marcus Winter (University of Brighton), Prof. Chris Watkins (Royal Holloway University of London), and Prof. Zhiyuan Luo (Royal Holloway University of London), and is funded by Brighton’s Connected Futures grant.

Contact tracing has been instrumental in the fight against disease outbreaks. However, most Bluetooth based contact tracing systems may only detect synchronous contacts, when both persons were in the same place, at the same time. The ‘asynchronous’ infectious contacts happening when the victims touch a contaminated surface at different times, are challenging to identify, because precise location tracking is both unavailable indoors without the GPS signals and is intrusive to the user’s privacy. More critically, many airborne viruses, such as COVID-19, may survive on certain materials such as cloth fabric for up to 4 days, and stainless steel, glass, latex for up to 7 days.

Ryan said “I am especially pleased to be able to work with colleagues from the School of Computing, Engineering and Mathematics on this innovative project. Contributing to, and drawing upon, a broad and deep body of knowledge is for me what working at a University is all about”.

This project aims to assess the feasibility of detecting asynchronous contacts, using smartphone sensor traces, including the accelerometer, magnetometer, barometer, and acoustic sound. The inspiration was that when two phones visited the same place, their respective sensor measures of the environment could be similar. The proposed tracing model works as follows. Firstly, a smartphone app will be developed to collect the sensor measures silently in the background. These data do not contain any intrusive location history, nor ever leave the phone without the user’s consent. Secondly, when a positive test is confirmed, the user may release the sensor logs for other participants to locally match their private traces for asynchronous contact detections.

The project will deliver a proof-of-concept study by collecting smartphone sensor data in various confined indoor spaces, along with ground-truth measures from specialist equipment. This pilot data will be analysed to confirm the feasibility of the approach. Due to the short timescale, this proposal will focus entirely on the office environment within the Brighton campuses.