Assistive Technology for the Physically Disabled[1]
Grace
Tay Lay Ting (grace.tay.2011@law.smu.edu.sg), 3rd Year student, Bachelor of Laws,
Singapore Management University
Executive
summary
This
paper examines how the use of assistive technologies can and have markedly transformed
the lives of the physically disabled. It will explore the trend in assistive
technology development as well as identify the implications which might arise
from the growth of the assistive technology market.
This
paper will focus on two major categories of assistive technology– assistive
technology which enhance mobility and assistive technology which augment
communication. These two categories are chosen as the author believes that the
basic touchstones to a respectable quality of life are essentially the ability
to interact with others and exert control over the external environment.
1 Introduction
"When you have a disability, knowing that you
are not defined by it is the sweetest feeling." – Anne
Wafula Strike (Anne Wafula Strike, 2010)
Born in Kenya, Anne Wafula Strike was struck down
with polio at the age of 2. The debilitating disease left her paralyzed from
the waist down. Fast-forward to the year 2004, Anne became the first Kenyan
wheelchair racer to represent her country at the Athens Paralympics. Today, she
is a British Paralympic wheelchair racer and a Sporting Ambassador.
All her sporting achievements would not have been
possible without the advent of the racing wheelchair. Marvelling over the
empowerment which her wheelchair has granted her, Anne reveals in a clip which
won BBC’s ‘My Story’ competition: “(the) first time I got my racing chair,
which was custom-made for me…I was ecstatic because I could go at speed,
something that I had never been able to do, ever ever in my life”. (Anne Wafula
Strike, 2010)
1.1 Physical
disability
Physical disability is the situation in which the individual’s
voluntary movements are inhibited due to the impairments in his/her skeletal or
neuromuscular systems. Disability can be said to result “when environmental
demands exceed an individual’s mobility resources (and thus restricts his/her)
participation (in the environment)”. (Rachel E. Cowan et al, 2012)
For those who are afflicted with severe disorders
which incapacitate their neuromuscular system, the individual may lose all (or
retain very minimal) control over voluntary muscular movements. In the most
extreme cases, the individual may be said to suffer from “lock in” syndrome,
unable to communicate with the outside world in any way.
1.2 Assistive
Technology
Borrowing from the definition of assistive
technology as codified in the United States Assistive Technology Act 1998, an
assistive technology is any “item, piece of equipment, or product system,
whether acquired commercially, modified, or customized, that is used to
increase, maintain, or improve functional capabilities or individuals with disabilities”.
(Assistive Technology Act, 1998)
Assistive technology is therefore used to augment
the daily activities of living of disabled users.
2 Historical Perspectives
For people with physical disabilities, the advent
of modern assistive technologies have not only changed, but revolutionised the
way they live and learn. The capacities made possible by assistive devices
today allow them to accomplish tasks which would have been unfathomable to
their counterparts years ago.
The history of modern assistive technology does not
go very far back however. According to Suzanne Robitaille (2010), the pioneers
of early assistive technologies are still alive today. Gregg Vanderheiden, who
had developed the Auto-corn in the 1970s, is now a resident professor at the
University of Wisconsin-Madison and is currently working on expanding the
accessibility of the Internet to disabled users.
In the United States, the rise of assistive technology
can traced to the pre-computer era, particularly the aftermath of World War II.
The great number of veterans disabled by war-time wounds posed a worrying
social problem and prompted the US Veterans Administration to launch a
prosthetic and sensory aids program. This was later reinforced by various
initiatives commencing modern research into rehabilitation and assistive
technology. (Suzanne Robitaille, 2010)
Assistive technology has come to be recognised
today as being of immense importance to augmenting the daily activities of
living of the physically disabled. A person with a disability should aim not
necessarily at mere body normality, but instead at life normality.
3 Current Situation
Today, numerous assistive devices exist on the
market to empower people with disability needs ranging from the mild to the
severe. These technologies encompass the low-tech, such as a walking cane or a
conventional manual wheelchair, to something as multifarious and complex as a
bionic limb or brain-computer interface technology.
Some of the most commonly employed assistive
technology devices today include those that are simple to use and minimally
costing, such as the mouth stick and the head wand. The former allows
individuals with no control over his hands to manipulate a stick-like device
using his mouth to type on a computer or control a trackball mouse to navigate
more complex interfaces. The head wand performs a similar function, with the
difference being that the stick is strapped to the head. This model may be more
practical and/or less tiring for some users. (Motor Disabilities: Assistive
Technologies)
For persons with very limited mobility, a
single-switch access device is available, which may be incorporated into other
assistive technology to allow the user to manipulate the device by clicking on
the switch. For instance, a person with only constructive control over head
movements can have the switch placed to the side of his head for easy
activation. (Motor Disabilities: Assistive Technologies)
Another alternative technology for individuals who
have little or no control over voluntary movements, is the eye-tracking device.
The device works by tracking movements of the user’s eyes to navigate through software
interfaces and enables the user to access a computer or type words on a screen.
For those who are unable to engage in meaningful verbal communication, this
technology represents a powerful speech assistive device which gives them a
‘voice’. (Motor Disabilities: Assistive Technologies)
Prosthetic limbs are another form of assistive
technology and they have a great potential to bring about ‘destructive’,
immensely transformative changes to lives of the physically disabled, allowing
many to fully realise their physical potentials.
An
outstanding example of such an individual is Oscar Pistorius, a South African
Paralympic runner who had both his lower legs amputated when he was a baby,
after he was born without fibula bones in his shin. Equipped with advanced
running prosthesis, Pistorius went on to make sporting history as the first
double-amputee to compete at the 2012 London Olympics against non-disabled
athletes. (Paul Kelso, 2012) Another stellar example alluded to at the start of
this paper is Anne Wafula Strike, Figure
1. Oscar Pistorius at the 2012 London Olympics a British Wheelchair racer.
Reproduced
from The Telegraph. (2012)
Were it not for both athletes’ prosthesis, neither
would have been able to fulfil their tremendous potentials as elite athletes.
Another technology which has been greatly
transformative for persons who suffer from complete paralysis of the body
(“locked in”) is brain-computer interface (BCI) technology. BCI contemplates
the “(harnessing of) electroencephalographic activity (EEG) or other
electrophysiological measures of brain function (to) provide an alternative,
non-muscular channel for sending messages and commands to the external world”. (J.R.
Wolpaw et al., 2002)
Figure 2 shows an instance of how BCI technology may
be incorporated and utilized. J.R. Wolpaw et al. (2002) explains how this BCI
system works: “Signals from the brain are acquired by electrodes on the scalp
or in the head and processed to extract specific features (e.g. amplitudes of
evoked potentials, firing rates of cortical neurons) that reflect the user’s
intent. These features are translated into commands that operate a device (e.g.
a simple word processing program, a wheelchair, or a neuroprosthesis). Success
depends on the interaction of the two adaptive controllers of user and system.
The user must develop and maintain good correlation between his or her intent
and the signal features employed by the BCI; and the BCI must select and
extract features that the user can control and must translate those features
into device commands correctly and efficiently.”
Figure
2. BCI System
Reproduced
from J.R. Wolpaw et al., (2002)
Over the past 15 years, BCI research has expanded,
fuelled by greater understanding of how the human brain works, the proliferation
of inexpensive computer equipment and growing acknowledgment of needs as well
as potentials of people with disabilities. However, the efficacy of BCI
technology currently is hampered by slow information transfer rates. As J.R.
Wolpaw et al. (2002) astutely observes: “the future value of BCI technology
will depend substantially on how much this transfer rate can be increased”.
4 Future Considerations
4.1 Trend
of assistive technology advancement
In the past, assistive technology devices are often
assembled sums of varied, discrete pieces of technology parts. Each part came
equipped with its own switch mechanism, power supply, control device and
mounting mechanism. Not surprisingly, this often led to user confusion and a
high cost of maintenance of the entire device. (P. Nisbet, 1996) The complexity
of such assistive technologies also made it inaccessible to the severely
disabled.
Thus, the challenge to provide practical solutions
to this group of disabled users has given rise to the present trend towards a
more seamless integration in the functionality of assistive devices, with fewer
attendant control options.
According to Rachel E. Cowan et al. (2012), this
trend is best evinced in the development of four key assistive technologies –
the powered wheelchair, prosthetic limbs, functional electrical stimulation,
and wearable exoskeletons – of which the first two will be further elaborated
upon by this paper, for the reason that they are two of the most commonly
employed assistive devices.
4.1.1 Powered
Wheelchair
A ‘shared control’ model is being explored in the
development of powered wheelchairs. This entails the elimination of mode
changes between different functionalities of the wheelchair. As mode changes can
impose a substantial mental burden on the user if he/she suffers additionally
from a cognitive impairment, this development could lead to improved device
accessibility and user-friendliness. A shared control approach envisages
greater integration of the user and the machine.
For instance, the Collaborative Wheelchair
Assistant (CWA) developed by a research group at London’s Imperial College
seeks to minimise the control required of the user by incorporating a
self-navigation system into the powered wheelchair. Pre-programmed paths are
encoded into the wheelchair interface and the user need only manage controls
for obstacle avoidance and speed changes. This greatly reduces the mental load
placed on the user in having to be constantly cognisant of wheelchair
navigation. (Burdet E. et al., 2009)
Another approach seeks to better exploit the user’s
inherent capabilities for controlling the wheelchair via the use of a body part
interface. This approach eliminates the need for a physical interface by allowing
information from any part of the user’s body to be mapped to sensors which can
then be manipulated for wheelchair control. This greatly improves the
accessibility of the powered wheelchair to severely disabled users, as any body
part with the greatest range of motion can be employed to steer the wheelchair.
(Casadio M et al., 2010)
Yet another method capitalizes on the user’s innate
capacities to engage his brain, through the use of BCI technology to capture
and translate intentions from brain electrical activity into real-time
wheelchair navigation. This involves the development of a “shared control
system” whereby the “computer ‘drives’ the chair between destinations using
pre-programmed paths while the user monitors the (pathway) for unexpected obstacles”
(Berger TW et al., 2008), not unlike the concept contemplated by the CWA.
4.1.2 Prosthetic
limb control
In the area of prosthetic
limb control, researchers in Europe have come up with 3 novel approaches, all
of which envisages greater interfacing of the user and their prosthetic.
The computer-vision
enhanced control (Dosen S. et al., 2010) essentially utilises camera software
to estimate the nature and dimensions of grasp control required of an object
and feeds this information to the attached prosthetic hand. The user is only
required to activate, aim and orientate the hand in line with the object of
choice. This enhances the autonomy of prosthetics and reduces user burden.
The peripheral nervous
system interface (Micera S. et al., 2010) seeks to tap into the nervous system
responsible for transmitting information between the brain and the users’ limbs
to control the substituted prosthetic. Results of studies into this technology
show that it is even possible to manipulate the nature of the prosthetic grip
by adjusting the number of interface electrodes. This approach has been
recognised as highly user-intuitive given that a pathway is provided for
sensory feedback between the user and his prosthesis.
The last innovation
identified is the kinematic/kinetic control system which provides for greater
synchronisation between the prosthesis and the remaining, normally functioning
limbs. Researchers of the Sensory Motor Systems laboratory at ETH Zurich have
developed a complementary limb motion estimation (CLME) technology which
harnesses the “physiological inter-joint couplings of the intact leg to
instantaneously determine (and consequently drive) the motion required of the
prosthetic leg”. (Vallery H. et al., 2011) This technology potentially broadens
the range of motion of the prosthesis and gives the user greater, more
intuitive freedom of movement.
4.2 Encouraging
continued research and development in assistive technology
With the growing recognition of the valuableness of
assistive technology for the disabled, there is a need to ensure continued
innovation and development in this area. For instance, further research and
innovation is needed to raise the information transfer rates of BCI technology,
in order that the benefit of the technology can be fully exploited.
National and state governments can play a crucial
role in facilitating research and development efforts. This can be done through
the provision of incentives for companies to set up research bases in the
country and by reducing regulatory red-tape. Grants can also be provided by the
government to encourage and facilitate collaboration between companies and
institutes of higher learning, to allow for wider pools of innovative ideas to
be tapped.
Further, intellectual property laws should be
strengthened in order to ensure that new innovations will receive adequate
property rights protection. This would go towards helping to create a conducive
and attractive environment for investment in assistive technology research and
development.
4.3 Addressing
the fragmentation of the assistive technology market
Currently, there is a lack of collaboration and
consultation between the various stakeholders of the assistive technology
industry (researchers, clinicians, marketers, consumers, etc.) in the larger
markets such as Europe and America. In the European Union, this has been
attributed to the differences in geographical, cultural and political
situations amongst the states and the lack of a common platform for the
facilitation of such collaboration. (Christian Buhler and Richard Barbera,
2011) However, in order to achieve the above-mentioned goals of greater integration
and to enable the benefits of innovation to be fully exploited as well as ensure
that innovation meet the needs and expectations of users, it is essential to
bring about greater collaboration.
This can be done through establishing common
platforms on which greater interaction and dialogue can take place between the
stakeholders. Such platforms can come in the form of an association with the
various stakeholders as members or possibly through forum initiatives set up by
individual stakeholder groups.
In order to ensure that new developments in
assistive technology meet the needs of consumers, the author believes that it
is essential to involve users in the development/innovation process. This is as
disabled persons themselves are conceivably the best candidates to provide
design specifications for what is meant by ‘intuitive’, ‘seamless’, and
‘non-obtrusive’ technologies. (Rachel E. Cowan et al., 2010)
Hence, it is pertinent to encourage and facilitate
such user involvement. Presently, developers are disinclined to engage
end-users in the development process due to inconvenience and resource-efficiency
concerns. In the United Kingdom for example, the presence of medical directives
presents a disincentive. The directives require that ethical approval must
first be obtained before users may be involved in the testing of devices. This
entails considerable paperwork and time which developers, especially those from
small companies, may wish to avoid and they may ultimately elect not to involve
users in the design and development process. (Avril D. McCarthy (2012).
Regulatory influences on assistive technology innovation: Enabling or
disabling? Technology and Disability, 24, 205-210.)
There is a need to raise awareness of the value of
user-consultation in the development of assistive technology. This may be done
through awareness campaigns, incentive grants to encourage companies to involve
disabled users as participants in testing out devices, or through reforms of
existing laws where necessary/realistic.
4.4 Ensuring
the availability and affordability of assistive technology
Ultimately, the purpose and value of assistive
technology advancements are only fulfilled when the benefits of such technology
may be enjoyed the target user groups. Hence, affordability and accessibility
of such assistive technology should be made a primary concern. The less
well-off must not be denied of an opportunity to lead a higher quality of life
simply due to financial disadvantages.
Fortunately, most countries do have in place
policies which seek to ensure that those who require assistive technologies
will have access to them. In Singapore, the Assistive Technology Fund provides
financial assistance for the purchase of assistive devices by disabled users
attending mainstream education and employment. (SG Enable, 2013) Similarly, the
governments of the United States, United Kingdom and Switzerland provide grants
to the disabled for the purchase of assistive technologies. In Canada, the
government has done away with the tax requirement for disabled persons in the
purchase of such devices. (PRWeb (USA), 2013)
5 Conclusion
In summary, assistive technology has come to be
recognized as representing great transformative potential and essential to augmenting
the quality of life of the physically disabled. Assistive technology takes
numerous forms, the most common of which is the powered wheelchair and
prosthesis, as well as increasingly, BCI technology incorporated into assistive
hardware. The rise of utility of the latter is fuelled in part by growing
understanding of brain functions as well as rapid advances in the area of
information and communications technology.
Modern advancements in assistive technology reflect
a trend towards greater integration of systems, with increasing interfacing
between user and device, leading to a reduction in user operational burden.
Also, developers are becoming cognizant that their innovations should be made
compatible with existing assistive devices on the market in order to achieve
greater applicability and accessible of their products. However, notwithstanding
the general shift towards the creation of comprehensive integrated systems
however, it is pertinent to realize that no one-size-fits-all model can be
employed in assistive technology. The sheer variety and uniqueness of
individual capabilities and extent of disabilities must be taken into account
in prescribing the most appropriate form of assistive technology.
The future implications of assistive technology
advances include the need to address the present undesirable fragmentation of
the industry, in order to remedy the problem of functionality of new developments
falling short of users’ needs and expectations; and the importance of ensuring
accessibility and affordability of assistive technologies in order that
disabled users are able to reap the extensive transformative benefits of such
technology.
All things considered, the future is an especially
exciting one for the physically disabled, whose lives await radical
transformation by new assistive technology innovations.
6 References
Anne Wafula Strike (2010). BBC My Story – In My
Dreams I Dance. Retrieved from http://annewafulastrike.blogspot.sg/2010/09/bbc-my-story-in-my-dreams-i-dance.html.
Assistive Technology Act of
1998. Pub. L. No. 108-364, §2432,112 Stat. 3627.
Berger TW, Chapin JK, Gerhardt GA, McFarland DJ,
Principe JC, Soussou WV, et al. (2008). Brain-Computer Interfaces: An
International Assessment of Research and Development Trends. World Technology Evalution Center, 2008,
1–281.
Burdet E, Zeng Q, Teo CL (2009). Evaluation of a
collaborative wheelchair system in cerebral palsy and traumatic brain injury
users. Neurorehabil Neural Repair, 23(5),
494–504.
Casadio M, Pressman A,
Fishbach A, Danziger Z, Acosta S, Chen D, et al. (2010). Functional
reorganization of upper-body movement after spinal cord injury. Exp Brain Res, 207(3–4), 233–247.
Christian Buhler and Richard Barbera (2011).
Assistive technology industry: A field for cooperation and networking. Technology and Disability, 23, 115-130.
Dosen S, Cipriani C, Kostic
M, Controzzi M, Carrozza MC, Popovic DB (2010). Cognitive vision system for control
of dexterous prosthetic hands: experimental evaluation. J Neuroeng Rehabil, 7, 42.
Figure 1. Oscar Pistorius
at the 2012 London Olympics, finishing last in 400m. (2012, August 6).
Retrieved from http://www.telegraph.co.uk/sport/olympics/athletics/9454624/Oscar-Pistorius-knocked-out-of-London-2012-Olympics-but-his-achievements-will-resound-for-years-to-come.html.
Figure 2. Graphic representation of the use of
brain-computer interface technology. Retrieved from Jonathan R. Wolpaw, Niels Birbaumer, Dennis J.
McFarland, Gert Pfurtscheller, and Theresa M. Vaughan (2002). Brain-computer
interfaces for communication and control. Clinical
Neurophysiology, 113, 767-791.
Jonathan R. Wolpaw, Niels
Birbaumer, Dennis J. McFarland, Gert Pfurtscheller, and Theresa M. Vaughan
(2002). Brain-computer interfaces for communication and control. Clinical Neurophysiology, 113, 767-791.
Micera S, Citi L, Rigosa J,
Carpaneto J, Raspopovic S, Di Pino G, et al. (2010). Decoding information from
neural signals recorded using intraneural electrodes: toward the development of
a neurocontrolled hand prosthesis. Proc
IEEE, 98(3), 407–417.
Motor Disabilities: Assistive Technologies.
Retrieved from http://webaim.org/articles/motor/assistive.
Paul Kelso (2012, August 6). Oscar Pistorius
knocked out of London 2012 Olympics but his achievements will resound for years
to come. The Telegraph. Retrieved
from http://www.telegraph.co.uk/sport/olympics/athletics/9454624/Oscar-Pistorius-knocked-out-of-London-2012-Olympics-but-his-achievements-will-resound-for-years-to-come.html.
P. Nisbet (1996). Integrating assistive
technologies: current practices and future possibilities. Med. Ng. Phys., 18(3), 193-202.
PRWeb (USA) (2013, October 25). Global Elderly and
Disabled Assistive Devices Market is Expected to Reach USD 19.68 Billion in
2019: Transparency Market Research. PRWeb
(USA).
Rachel E. Cowan, Benjamin J Fregly, Michael L
Boninger, Leighton Chan, Mary M Rodgers, and David J Reinkensmeyer (2012).
Recent trends in assistive technology for mobility. Journal of NeuroEngineering and Rehabilitation, 9, 20-29.
SG Enable (2013, July 1). Assistive Technology Fund. Retrieved from http://www.sgenable.sg/Schemes__Assistive-Technology-Fund.aspx.
Suzanne Robitaille (2010). The Illustrated Guide to Assistive Technology. New York: Demos
Medical Publishing.
Vallery H, Burgkart R,
Hartmann C, Mitternacht J, Riener R, Buss M (2011). Complementary limb motion
estimation for the control of active knee prostheses. Biomed Tech (Berl), 56(1), 45–51.
No comments:
Post a Comment