The cap read the thoughts of the team

It looks like a regular baseball cap. But when worn, this hat can detect and analyze an electroencephalogram (EEG) signal from the brain. It even tells you whether you are sleepy while driving or not, based on a brain wave pattern. Similar technology can allow you to control consumer electronics such as TVs, computers and air conditioners, all just by thinking about them.

The brain-computer interface consists of a cap with 6 electrodes (an electrode located below the ear) that detects the team's EEG signal.In the current sample, the brain-detectable system responds to the alertness of the team.(Photo: Chin-Teng Lin)

A group of Taiwanese researchers designed a new biological signaling system inside a cap with the purpose of making it more convenient and easy to use in everyday life. Because this system is wireless, portable and can handle data and feedback in real time, it can be useful for many indoor and outdoor applications.

According to researcher Li-Wei Ko, Chiao-Tung National University in Taiwan, 'This work describes in detail the design, development and testing of wireless, mobile and non-intrusive EEG systems. In order to continuously monitor the temporal brain kinetics without the lead gel applied to the scalp. This system accesses online EEG signals and processes real-time signals. It can be used in many applications. We only apply to driving, such as alertness testing. '

Together with Ko, researchers at Chiao-Tung National University, National Cheng-Kung University and University of California, San Diego, published the work on the brain-computer interface system on an edition of IEEE Transactions. on Biomedical Engineering.

Researchers explain that by measuring EEG signals, the BCI system can monitor an individual's cognitive and physiological states. The system uses advances in sensors and information technology to reduce energy consumption and production costs. Currently, the system can operate for about 2 days before needing to charge lithium-ion batteries, but researchers hope to increase battery life in the future.

Users wear hats with 5 dry electrodes, and an electrode behind the left ear, collecting EEG signals. The EEG signal is then transmitted wirelessly to the data receiver, where they are processed in real time using a dual-core processor. The BCI system transmits data via Bluetooth within a distance of less than 10m (for example in driving applications), and via RF within distances up to 600m (in sports applications). Next, the processed signal is transmitted back to the helmet, where the data can be stored, displayed in real time on the screen, or used to generate an audible warning signal.

For example, to test the accuracy of a real-time driver's alerting system, the researchers performed experiments with virtual reality highway driving environments. The tester 'drove' a real vehicle mounted on the platform, with a 3-dimensional screen around. The car suddenly drifted away from the center of the road and the driver had to adjust the direction. The longer they adjust the direction, the less alert they are.

Drivers also wear a BCI hat, an EEG signal detector while they drive so that researchers can compare the alertness of the BCI system with the alertness decided by the virtual reality system. The average correlation of the two measurement methods is 75%, indicating that the BCI system determines the user's alertness quite accurately.

Besides driving, mobile EEG-aware BCI system can be used for a variety of other applications. For medical purposes, researchers believe that the technology could be used to take care of the elderly, medical supervision and exercise. They also hope it can be applied to the control of household electrical appliances, previously tested devices for individuals with disabilities.

Ko said 'We will shrink this system and apply SoC (System on chip) technology. We will also create more applications, using EEG wireless and mobile systems. '