Macquarie University researchers develop new anti-drowning technology

A new wearable device that detects signs of drowning and alerts lifeguards to the swimmer's location is being trialled by Macquarie University researchers.

The Macquarie University research team’s work has seen the development of a prototype wristband device - currently named APPTRAKK -­ detects a swimmer's heart rate, oxygen and movement patterns, using floating transmitters to send potentially lifesaving information to rescuers.

The device uses sensors to detect heart rate, blood oxygen, water depth, submersion time and movement patterns, overcoming substantial challenges like underwater wireless communication to create a system with the potential to save thousands of lives worldwide each year.

When a person is missing in the water, the time taken to locate them is critical to their survival.

The waterproof device can be tailored to suit both the user and the conditions, monitoring people in a range of hazardous aquatic environments including back yard swimming pools for children using artificial intelligence to identify distress in swimmers.

Over this past winter, the team has continued improving the device, making it smaller and adding features such as the ability to customise alerts to suit different swimmer capabilities.

Introducing the technology, Dr Mohsen Asadnia, Associate Professor at Macquarie University’s School of Engineering, explained “a surprisingly high number of people who drown are good swimmers.

“Drowning can happen quickly and quietly and people swimming in deep water aren’t easy to keep track of - that’s why a wearable device is ideal."

Dr Asadnia points to a substantial body of research shows that drowning tends to be silent, as people use most of their energy trying to keep their heads above water, and if they panic as water gets into their airways, may be unable to call or signal for help.

He states “a drowning person is usually only spotted if someone sees them struggling in the water with difficulty breathing.

“When a person is missing in the water, the time taken to locate them is critical to their survival.”

Drowning prevention strategies include swimmer education, regulations and close monitoring, but while all of these have reduced deaths, hundreds of Australians still drown each year.

However, Dr Asadnia “developing an accurate device to detect dangerous situations where a swimmer is in  trouble in the water or on the verge of drowning, could dramatically reduce water-related deaths and accidents, save lives and reduce the amount of money spent on search and rescue.”

The research has been partly funded by the Smile Like Drake Foundation, which was established by the Drake family to develop and promote water safety solutions, in memory of 23-year old law student and former professional surfer Christopher Drake.

In March 2013, the family went through terrible tragedy when their son drowned, thrown from the North Curl Curl rock pool into rough seas by a freak wave while helping others to safety, with rescue teams unable to recover his body for five agonising days.

Nicolle Drake, Chris’s mother, commented “we believe that Chris’s drowning was preventable, so we utilised our deep grief to commence our own analysis of fatal and non-fatal drownings in ocean pools, dams, rivers, waterways and backyard swimming pools.”

She says that time is critical when trying to locate a missing person and the device could fast-track rescue and resuscitation, suggesting that “if Chris was wearing APPTRAKK at the time he went missing, it may not have changed the outcome however, we would have been able to say goodbye and donate his precious organs.”

Macquarie University engineering professor Michael Heimlich began researching the device in 2017, and Dr Asadnia has continued to lead the work following Professor Heimlich's death earlier this year.

Image: Dr Mohsen Asadnia and Salman Jalalifar test the APPTRAKK device. Credit: Maja Baska/Macquarie University.