Motivation for the Proposal
For a person with disabilities, particularly those who are paralyzed or cannot move independently, it is a challenge to carry out everyday activities that are seemingly simple for normal healthy people. For example, it is not possible for them to drive or move independently. They will face difficulties in giving input to devices, such as a computer or audio/visual devices. It is also a challenge to them to express their feeling or emotion to other people, when speech and expressions are obviously not as easy as people without similar disabilities.
Traditionally, among techniques applied and investigated in the past decades, newer approaches aim to enable hands-free control using various human-machine interfaces (HMI). Examples of investigated HMI are such as techniques using muscle signals (Electromyography - EMG) (Felzer & Freisleben, 2002), eye movements (Electrooculography - EOG) (Barea, Boquete, Mazo & Elena, 2002) or video-based eye gaze tracking (Murata, 2006), human body movements (limited limb movements, head gestures, facial expression etc.) (Ju, Shin & Kim, 2008), voice command (Harada, Landay, Malkin, Li & Bilmes, 2008) and brain signals (Electroencephalography - EEG) (Iturrate, Antelis, Kubler & Minguez, 2009).
To provide a feasible and affordable solution to the targeted users, unobtrusive techniques based on commercial-off-the-shelf (COTS) devices can be an attractive option. The availability and cost of these products will be an advantage as compared to specialized, high-end and/or medical-grade devices. They are usually simpler and more intuitive than the high-end devices in terms of daily usage. Common shortcomings are the trade-off of accuracy and sometimes efficiency. However, there are situations where a fair trade-off is expected but patients may still accept the unobtrusive COTS devices, as long as the errors and loss of efficiency are not life threatening. For example, for self-initiated vital information monitoring and measurements at home, away from health care institutions and professionals, may be worth the above mentioned trade-off, because patients do not need to travel to their assigned health care institutions to perform periodical check-up (Lau et al., 2010). Patients may opt for in-home recuperation, as long as the monitoring procedures and reporting can be performed by medical experts with acceptable accuracy and efficiency.
One specific technology listed above is the usage of EEG devices to allow “mind-control”-based approaches to help patients to express themselves, control and move around. Particularly for patients with amyotrophic lateral sclerosis (ALS), cerebral palsy or spinal cord injury, this technology enables them to capture their “thoughts” through the translation of their measured brain signals into usable commands or machine-comprehendible thoughts.
This chapter intends to present a survey of related work that applies EEG-devices for patients with movement disabilities. Focus will be given to the COTS devices and the techniques used for the respective solutions.