A new device analyses brain waves to warn drivers before they nod off

Good Vibrations

A new device analyses brain waves to warn drivers before they nod off

Published: 12 Apr 2013 at 00.00

As Songkran arrives, Thais are again warned to steer away from drunk driving during the water-splashing festival to prevent what is usually a spike in road accidents.

Researchers at Mahidol University’s department of biomedical engineering have devised a patentpending sleep alarm system to detect drowsiness via brain signals.

But while statistics indicate most accidents are caused by drunk driving, Manoon Leechawengwongs, chairman of the Anti-Drowsy Driving Fund of the Ramathibodi Foundation, thinks otherwise.

Dr Manoon believes drowsiness causes 80% of road accidents that occur while driving. In fact, he believes drowsiness is the cause of a large percentage of all deaths in Thailand. Official figures state drowsiness caused 2-3% of all deaths.

He advises motorists to drink coffee if they are feeling drowsy in order to quicken the awakening process if they do fall asleep at the wheel.

“The Public Health Ministry is afraid people will become addicted to coffee, so they do not want people to drink it. But this is a life-saving issue,” said Dr Manoon.

Yodchanan Wongsawat, director of the brain-computer interface lab at Mahidol University’s department of biomedical engineering, said brain waves are divided into five levels when people sleep.

Research conducted by his team on a group of 50 people indicated that waking up at the second stage, which is around 15 minutes into sleep, results in the highest level of freshness.

But how do we know when we are about to doze off?

A team of seven researchers at the department have been devising a patent-pending sleep alarm system for three years to detect drowsiness via brain signals. The device is said to be the first of its type in the world to use both brain signals and blinking to detect drowsiness.

The device is said to have 90.4% accuracy, and is inserted in a headband that is worn comfortably in a cap or sport sweatband.

The device consists of three main components: the pad, sender and receiver. The pad will be in contact with the forehead to receive the brain wave signals. The sender box attached to the pad will filter, amplify and send the wireless signal to the receiver box. The receiver will pass the signal through the algorithm to calculate the drowsiness level.

When the index reaches an unsafe level, the receiver will sound an early alarm to alert the driver, some five to 10 seconds before he or she falls asleep.

The first batch of 1,000 devices is being produced for the market by May, with another 20 now available for commercial tests.

Mr Yodchanan expects the production of 10,000 devices per annum will be reached in five years.

The product has caught the eye of logistics firms and the Royal Thai Police. “SCG is currently having their drivers test the device. Damage from cement truck accidents is worth millions of baht,” said Mr Yodchanan.

The drowsiness data can also be sent to the head office in real-time via a global positioning system (GPS) installed on the truck.

Three samples have been sent to the Royal Thai Police for education purposes.

The researchers also plan to set up a company and open a website to sell the devices online to overseas customers. Indonesia and Singapore have expressed interest in purchasing the devices.

The production cost is 3,000 baht per device, but research and development is under way to lower costs below 1,500 baht.

Mr Yodchanan said the retail price should be no more than 8,000 baht for now, compared to 100,000 to 1 million baht for similar devices used in hospitals.

“Usually the price is set 10 times higher than the production cost, but I don’t want to price it more than 8,000 baht for the Thai market,” he said.

Future devices will contain a “sleep lab” to analyse problems that occur during sleep. Clients can be sent to doctors for further examination.