Accessibility
Worldwide need for accessibility support for people with disabilities
Finding good data about disability incidence worldwide is challenging. In America and Europe, we have some general statistics:
- Half of all disability incidence numbers are from people over 65 years of age
- Roughly 0.1% of the population is blind
- Roughly 0.1% of the population has a speech impairment (could benefit from their computer talking for them)
- Roughly 0.05% of the population is deaf, while 0.2% is hard of hearing
Since we tend to get more disabilities as we age, we would expect these percentages to be lower in children. On the other hand, health issues like West Nile Virus that are a huge cause of blindness (and the altitude in places like Tibet, another cause of blindness) aren't significant issues in America and Europe - so you would expect that the incidence of disabilities in the OLPC markets will be higher.
So, until we get better data, it probably makes sense to adopt as rough numbers for OLPC children the general percentages from America and Europe taken across all age ranges.
This means that if the OLPC project reaches every child (so roughly 1 billion systems), we will need to serve 1 million blind children, and 1 million children who have a speech impairment, and 2 million children who have difficulty hearing.
Accessibility and Assistive Technology
Even in "first world" countries like the USA, Assistive Technology and Accessibility adaptations are expensive. People with physical or mental disabilities are often, due to their disability, in the lowest income classes, and have difficulty affording the technologies required.
In the Open Source Software community, a fair amount of software already exists to aid the disabled. However, they are often not installed or configured by default, and can be extremely difficult to add by a normal user.
Under this area, we should seek to list specifically:
- what Assistive Technology software packages should be included in the default olpc distribution
- how they should be configured by default
- what technologies need to have improved documentation to be useful
Accessibility ideas for the OLPC laptop
For people with physical impairments
Physical impairments range from fairly minor (difficulty using the mouse), to more significant (unable to use a normal keyboard, but still have a fair amount of upper body dexterity), through to being paralyzed from the neck down. Repetitive stress injury is another issue, though incidence of that is currently probably quite low in OLPC's target market.
Roughly 0.2% of the U.S. population has "difficulty using hands and fingers, e.g. to pick up a glass or grasp a pencil". By our logic above, that works out to 2,000,000 target OLPC users
- OLCP should be fully operable from the keyboard, without requiring the trackpad for operation. Something like a painting program might be an exception; but otherwise, tasks like launching programs and browsing the web and reading a book (and ideally most games) should be fully operable from the keyboard. There should be a visible indication of which object has the keyboard focus (and this visual indication should become more obvious in various themes for vision impairments)
- OLCP should support the AccessX suite of keyboard enhancements (StickyKeys, MouseKeys, BounceKeys, etc.)
- OLCP should support external keyboards & mice/trackpad devices
- OLCP should support an on-screen keyboard (e.g. [GOK]), and likewise support hardware input from switches (USB, but perhaps also inexpensive ones connected via the microphone port), and also head mice (USB, but perhaps also one that uses the built-in camera tracking a reflective piece of clothing or dot pasted onto a persons forehead or glasses)
For people with visual impairments
There is a fairly wide range of vision impairments. They range from the fairly minor (color blindness, or vision that isn't too bad, but no longer 20/20), to pretty significant (18 point text isn't large enough), all the way through to total blindness.
For people with minor visual impairments
- Sugar and all OLPC application should use a luminosity contrast ratio of at least 3:1 by default; ideally 5:1
- Color should never be the only indication of something (e.g. using red text to set off something from black text)
- Sugar should include several "themes" for vision impairments, including several with different contrast settings (e.g. a "high contrast" theme) and large print. All applications should respect these settings. The interface for launching applications should be enlarged in the large print theme (cf. the themes in the default GNOME desktop).
8% of males of European descent have color blindness; 1% of females of European descent. Numbers are lower for Asians and Native Americans; lowest of all for blacks.
For people with 'low vision'
- OLPC should support software magnification. Magnification should track keyboard focus and the text input caret. It should also magnify the mouse cursor.
- Mouse-only enhancement would be useful (mouse-trails & separate mouse cursor enlargement, to help locate the mouse cursor)
Roughly 0.2% of the U.S. population has "difficulty seeing words in newspaper". By our logic above, that works out to 2,000,000 target OLPC users.
For people who are blind (from 'legally' blind through to totally blind)
- A screen reader which supports text-to-speech and works with all applications (Orca is the obvious choice here)
- Lightweight text-to-speech in all languages (eSpeak is a good candidate)
Roughly 0.1% of the U.S. population has "Unable to see words in newspaper at all, or self identify as 'blind'". By our logic above, that works out to 1,000,000 target OLPC users.
For people with hearing impairments
The main things we need to do for folks with for hearing impairments are:
- Not use exclusively audio for getting the attention of a user (e.g. the ShowSounds feature to flash the menu bar / screen during a system beep)
- Ensure that all media players support captioning, and all media is captioned
But beyond that, thanks to the built-in video camera in the OLPC, we have the possibility of supporting sign language chat. In the BTest-2 systems, using the bulit-in camera application the frame rate seems to be on the edge of good enough for this (in an informal test performed at the CSUN Conference on Technology and Persons with Disabilities). With a promised 30fps frame rate of 640x480 resolution, this ought to work. Further tests need to be carried out over a wireless video chat to be certain.
For people with cognitive impairments
The Sugar user interface already addresses many of the needs of people with cognitive impairments. It has very limited use of text, and provides an uncluttered interface. However, there are a number of additional things we can do for folks with cognitive impairments:
For people with speech (generation) impairments
- ...
Misc.
The following pages in this wiki may be of interest.
Accessibility Computing Numerical Pointer
Helping Blind and Visually Impaired People
Although probably not a main target of the OLPC effort, the blind and visually impaired community seems to be a tight and cohesive community with clear requirements and needs, that could piggy-back on the effort as a whole, and hopefully make technology more multi-media in the true sense. Some resources or ideas:
- JAWS - from Freedom Scientific. Non-free.
- Orca - from Gnome, FAQ and wiki. LGPL license
- There's a Grupo de usuarios ciegos y deficientes visuales de GNU/Linux (blind and visually impaired GNU/Linux users group) and its wiki.