Smart bracelet can sense danger, call for help

Scientists have developed a smart bracelet that can automatically detect physical or sexual assault, scare off the attacker and call for help.

Upon detection that the user is in danger, it is programmed to emit a loud beeping sound and red strobe lights begin to flash in an effort to scare the attacker off and to alert other people who may be nearby.

"A major challenge to assault prevention is that, during an assault, victims often do not have an easily accessible way to call for help," said Ragib Hasan, associate professor at the University of Alabama at Birmingham (UAB) in the US.

"Whether calling 911 or using an emergency alert app or device, each of these tools requires users to press a button in order to call for help. That is often not possible while a violent act is taking place or if a person is unconscious as a result of the assault," said Hasan.

The Smart Jewelry Bracelet, which is currently a prototype, uses machine learning and a multitude of sensors to analyse a user's movements in order to detect an assault as it is taking place.

Upon detection that the user is in danger, it emits a loud beeping sound and red strobe lights to scare the attacker and alert people nearby.

The device then connects to the user's smartphone via Bluetooth and instantly sends emergency messages and coordinates of the user's location to emergency personnel and a list of contacts predetermined by the user through a mobile app.

The bracelet contains a small microcontroller equipped with a gyroscope, accelerometer, temperature and pressure sensors, GPS, and microphones.

"The sensors allow the bracelet to collect user activity and vital signs continuously," said Jayun Patel, a graduate research assistant at UAB.

"It can also determine the orientation of the user, for example, whether they are standing or lying down. A machine learning algorithm detects and differentiates the user's regular movement and unexpected and sudden movements that can be indicative of an assault," said Patel.

While the bracelet was primarily designed for detecting assault, the device can also be used by the elderly or those with disabilities to automatically detect sudden falls or other risky movements.

Patel hopes to refine the design and expand the technology to other everyday items worn on the body, such as earrings and shoes.

The Smart Bracelet prototype cost less than USD 40 to create and can be made even cheaper if it is mass-produced commercially.