BRAIN WAVES USED TO CONTROL WHEELCHAIRS

Technology that allows people to steer a wheelchair using only their thoughts has been developed in a collaborative research project involving Toyota.

The system interprets brainwaves to enable the wheelchair to move forwards and turn left or right almost instantly.

It is among the fastest systems in the world for analysing brain waves - taking just 125 milliseconds (one-eighth of a second) compared with several seconds for previous systems.

Rather than using their muscles or speaking, a person in the wheelchair has a cap with electrodes that read and analyse brain waves.

Brain-wave analysis results are displayed on a panel so quickly that drivers do not sense any delay.

The system has the capacity to adjust itself to the characteristics of each individual driver, thereby improving the efficiency with which it senses a driver's commands.

Drivers can get the system to learn their commands (forward, right, left) quickly and efficiently.

The new system has succeeded in having drivers give commands to their wheelchairs with an accuracy rate of 95 per cent.

This technology is expected to be useful in the field of rehabilitation and for physical and psychological support of wheelchair drivers.

Research into personal mobility is part of Toyota's long-term strategy of helping to make people healthy and comfortable in ways that go beyond automobiles.

The system was developed by the BSI-TOYOTA Collaboration Center (BTCC), which was established in 2007 by RIKEN, an independent administrative institution.

It is a collaborative project with Toyota Motor Corporation (TMC), Toyota Central R&D Labs, Inc. and Genesis Research Institute, Inc. as well as BTCC's non-invasive Brain-Machine Interface (BMI) unit.

Recent developments in BMI technology have received attention because they allow elderly or handicapped people to interact with the world through signals from their brains, without having to give voice commands.

BTCC's new system fuses two of RIKEN's technologies - Blind Signal Separation (BSS) and space-time-frequency filtering (STF).

The technologies allow brain-wave analysis to occur much faster than with conventional methods.

BSS separates the "noise" components and useful components from brain signals that can be used to control the wheelchair.

Using multiple electrodes placed on the scalp, the system records the brain's spontaneous electrical activity (or electroencephalography [EEG] signals).

Space-time-frequency filtering extracts space and time patterns and frequency oscillation data from EEG electrodes to discriminate significant features and components, which are able to control the wheelchair reliably.

Plans are underway to utilise this technology in a wide range of applications centred on medicine and nursing care management.

Improvements being considered include increasing the number of available commands and developing more efficient dry electrodes.

So far, the research has centered on brain waves related to imaginary hand and foot control.

However, through further measurement and analysis, it is anticipated that this system may be applied to other types of brain waves generated by various mental states and emotions.