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Thermostat regulation via a Web interface:
For visually impaired and sighted individuals
Engineering Psychology
Seminar on Assistive Technology
Fall 2005
Anne Adams
Britt Caldwell
Lisa Mauney
Jamie Weitz
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Table of Contents
Overview of the Project ..................................................................................................................... 4
Introduction ........................................................................................................................................ 5
Visual impairment .......................................................................................................................... 5
Assistive Technology in the Home ................................................................................................ 8
Assistive Technology and Computer Use .................................................................................... 11
Ways to Receive Information ...................................................................................................... 11
Choosing a general design approach and strategy ....................................................................... 14
Assistive Technology ............................................................................................................... 14
Universal Design (UD). ........................................................................................................... 15
Participatory Design................................................................................................................. 16
Building an Assistive Technology --- The Design Process ............................................................. 19
Target Users ................................................................................................................................. 19
Getting started with a Needs Analysis ......................................................................................... 19
Participants. .............................................................................................................................. 19
Method. .................................................................................................................................... 19
Results. ..................................................................................................................................... 20
Implication for design. ............................................................................................................. 21
Three different design alternatives............................................................................................... 22
Existing solutions and implications for our design ...................................................................... 23
Important User Characteristics (revisited) ................................................................................... 25
Task Analysis ............................................................................................................................... 25
User Task Characteristics. ....................................................................................................... 25
Environment Task Characteristics ........................................................................................... 25
Higher Level Task Analysis..................................................................................................... 27
Detailed Task Analysis/Function Allocation ........................................................................... 27
Social and Technical Context. ................................................................................................. 30
Participatory Design..................................................................................................................... 30
Participants. .............................................................................................................................. 31
Method. .................................................................................................................................... 31
Table 1. Results of the second interviews ................................................................................ 33
Implication for design. ............................................................................................................. 35
Creating and evaluating the prototype ............................................................................................. 36
Information about controls and displays to consider ................................................................... 36
Creating the prototypes ................................................................................................................ 38
Evaluating the prototypes ............................................................................................................ 39
Participants. .............................................................................................................................. 39
Materials. ................................................................................................................................. 39
Procedure. ................................................................................................................................ 40
Results of prototype evaluation – sighted participants .................................................................... 41
Mental model and system image.................................................................................................. 41
Feedback ...................................................................................................................................... 42
Scheduling.................................................................................................................................... 42
Website 1 specific results (combo boxes, time range) ................................................................. 43
Website 2 specific results (radio buttons, 1 time) ........................................................................ 43
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Website 3 specific results (links, 1 time) ..................................................................................... 43
Summary for graduate students ................................................................................................... 44
Results of prototype evaluation – visually impaired participants .................................................... 45
Website 1 specific results (combo boxes, time range) ................................................................. 45
Website 2 specific results (radio buttons, 1 time) ........................................................................ 45
Website 3 specific results (links, 1 time) ..................................................................................... 46
Summary for visually impaired participants ................................................................................ 46
Discussion/Recommendations ......................................................................................................... 48
General Website Problems/Recommendations ............................................................................ 48
Website #1 (combo boxes)........................................................................................................... 50
Website #2 (radio buttons) ........................................................................................................... 50
Website #3 (links) ........................................................................................................................ 51
What We’ve Learned ....................................................................................................................... 52
References ........................................................................................................................................ 54
Appendix A – Screenshot of Website 1 (combo boxes, time range) ............................................... 58
Appendix B – Screenshot of Website 2 (radio buttons, 1 time) ...................................................... 59
Appendix C – Screenshot of Website 3 (links, 1 time).................................................................... 60
Tables 2-10........................................................................................Error! Bookmark not defined.
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Overview of the Project
The purpose of this project was to develop an Assistive Technology (AT) with a special
population in mind, but which was also a technology that can be potentially useful for a broader
population as well. The population we chose to focus on was the visually impaired, that is, blind
or low vision individuals. We were interested in focusing on issues they had with independent
living in terms of performing household tasks. After learning more about visually impaired people
we performed a Needs Analysis to receive direct feedback from visually impaired individuals in
terms of what assisting technology they would like to have. Using this information, we narrowed
our scope for the project to designing an accessible thermostat. We performed background
research on existing thermostats and considered further feedback from the visually impaired as part
of the participatory design process. The next step was prototyping and evaluating our Virtual
Thermostat. We presented three mocked-up versions to both sighted subject matter experts and
visually impaired participants, who evaluated the Virtual Thermostat by performing specific tasks
with the system and providing us with feedback. User preference, usability, and accessibility of
the interfaces were our focus in the evaluation.
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Introduction
Visual impairment
To learn about our user population we looked up the definition and statistics in regards to
visual impairment. When looking at statistics on “visual impairment” it is important to ask how
“visual impairment” is defined and who is included. Defining this term is important because
improper use of the terms visually impaired, blind, and low vision in combination with the
respective statistics can provide an inaccurate picture of their prevalence in the population. The
World Health Organization (WHO) is a source frequently cited for the definition of and statistics
on visual impairment (Resnikoff, Pascolini, Etya’ale, Kocur, Pararajasegaram, Pokharel, &
Mariotti, 2004).
The definitions of low vision, blindness, and visual impairment, according to the 10th
Revision of the WHO International Statistical Classification of Diseases, Injuries and Causes of
Death, are as follows:
... low vision is defined as visual acuity of less then 6/18, but equal to or better than
3/60, or corresponding visual field loss to less than 20 degrees, in the better eye
with best possible correction. Blindness is defined as visual acuity of less than
3/60, or corresponding visual field loss to less than 10 degrees, in the better eye
with best possible correction. Visual impairment includes low vision as well as
blindness. (WHO, 2004)
It is important to note that the term visual impairment includes both low vision as well as
blindness.
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The WHO estimated that in the year 2002, about 161 million people were visually impaired
worldwide. Of these 161 million people, about 124 million (77%) had low vision and 37 million
(23 %) were blind. The 2002 estimates by WHO show that the USA is amongst those with the
lowest prevalence rates. The prevalence of blindness in the US was 0.20% (compared to 0.57%
worldwide) and of low vision 1.20% (compared to 2.0% worldwide). In terms of geography, 90%
of people with vision impairments live in developing countries (Resnikoff et al., 2004; see also
Figure 1, WHO, 2004). Despite these relatively low numbers for the USA, this still means that of
the people living in the USA in 2002 about 4.7 million people were visually impaired, 4 million
(85%) of which had low vision and 0.7 million (15%) were blind.
Figure 1: “Global estimate of visual impairment by WHO region” (taken from WHO, 2004)
As acknowledge by WHO (2004), these numbers are likely biased. People with refractive
errors have not been included, so the number for people with low vision is probably
underestimated. A comparison to previous years’ data and inferences about trends are somewhat
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problematic because of the different definitions used, different sampling, and current practice of
collecting data via surveys. Furthermore, some countries have adopted different policies and
practices to deal with vision impairment (e.g., India) (WHO, 2004). An additional factor to keep
in mind is that the definition is only concerned with vision after correction, which possibly
accounts for part of the lower numbers in industrialized countries.
In general, more females than males have some form of vision impairment (ratios between
1.5 and 2.2), and there are two age-related links to blindness. The first link concerns the younger
age in terms of childhood blindness: About 1.4 million vision impaired people worldwide are
below the age of 15. It is noteworthy that childhood blindness as a cause for blindness does not
differ that much between the USA (3.1%) and the world average (3.9%). The second link
concerns the older age. WHO notes that visual impairments are due less to infectious-disease and
more to age-related blindness. While only 19% of the world’s population is over the age of 50, a
surprising 82% of blind people are over the age of 50. The 3 leading causes of blindness
worldwide are cataracts (47.8%), glaucoma (12.3%), and age-related macular degeneration (8.7%)
– see also Figure 2. In the USA, the leading causes of blindness are age-related macular
degeneration (50%), cataracts (18%), and diabetic retinopathy (17%) (Resnikoff et al., 2004).
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Figure 2: Global causes of blindness as a proportion of total blindness in 2002 (WHO, 2004)
These statistics show that vision impairment affects a significant proportion of people
around the world. Even in the USA, vision impairment is a real phenomenon and requires
investigation into how this affects everyday life. The next step for us was to find out how living
with a visual impairment affects very simple tasks such as going to the grocery store or picking out
clothes to wear. We decided to investigate assistive technology in the context of the home.
Assistive Technology in the Home
Many visually impaired individuals want to be as independent as possible when it comes to
taking care of things in their daily life. Regardless of being at work or at home, people like to
maintain autonomy over the tasks they perform, regardless of the devices needed to complete the
tasks. Many assistive technologies (ATs) have been designed or redesigned to suit tasks
performed at home. AT products for the home typically fit into one of three categories: (1)
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labeled, (2) explicitly manufactured, or (3) off-the-shelf products. Products can be augmented to
suit visually impaired users by labeling certain areas with high contrast marks or Braille. Braille is
a system of touch reading in which 63 different characters can be formed from embossed dots
arranged in various patterns in a quadrangular space (Reilly, 2001). Two examples of labeling are
marking stoves with a dark marker for high, medium, or low settings and placing Braille labels on
the microwave keys for certain settings. Products can also be manufactured explicitly for visual
impairments by enhancing auditory features (e.g., a talking caller ID). Lastly, products can remain
the same as commercial off-the-shelf devices and users may adapt to their functionality, such as
when cell phone users just memorize the layout of their phone. Many products and appliances
around the house can be redesigned by the user or produced commercially by a company to better
suit the needs of visually impaired individuals, while at the same time keeping them in control of
maintaining their home.
The types of ATs used around the house have different interaction styles, typically to suit a
specific kind of task (e.g., knowing who is calling on the telephone) or to be done by a specific
user (e.g., a person with arthritis). Devices can be grouped into three categories depending on size
and ability of the device. Small remote devices, such as talking watches, are mobile with the user
(Dynamic Living, Inc., 2005). Stand alone devices such as talking phones, alarm clocks, scales,
pill bottle identifiers, and thermometers are stationary but provide the user with direct control over
the device. This direct control can be exercised via voice recognition, speech output, as well as by
typical displays and controls (Dynamic Living, Inc., 2005). Environmental or integrated control
systems are broader in a sense as they control and monitor things like heat, energy, and lights
(HomeTech Solutions, 2005). Depending on the design, integrated control systems allow the user
to control the home environment remotely, such as from an office computer.
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In all three of these device categories, talking products are fairly common. As previously
mentioned, talking devices exist to assist visually impaired individuals by utilizing auditory
interfaces (Dynamic Living, Inc., 2005). Appliance-wise, most augmented systems have Braille
dots to guide users, but they do not have speech output. One exception is the talking microwave
oven (SightConnection, 2005) but it comes at a high cost of $395 (compared to $100-$200 for a
non-talking 1 cubic foot microwave). Users of a talking thermometer and a talking caller ID claim
that the devices just did not work. Many devices may also be difficult to program for a low vision
user and need to be set up by someone else which could pose a problem for visually impaired
individuals who live alone. In general, however, talking devices add autonomy for users to
monitor and control their home life.
With more than 57% (62.3 million) of U.S. households connected to the Internet (Zanthus,
2003), the prevalence of Smart Homes and environmental or integrated control systems has grown.
Smart/Aware Homes would integrate safety, environmental control systems, communication,
energy-control-systems, and entertainment through the telephone or Internet (Laberg, 2004).
Users could monitor and control environmental settings in their home from remote locations. This
remote access is appealing not only for visually impaired individuals, but also for those with any
disability, older adults, and adults in general. Visually impaired users could control their home
environmental systems from work on a computer that is designed to use a screen reader and have
speech recognition input. This setup would allow a blind person, for example, to independently set
his or her house to a specific temperature when they walk in the door. The development of
Smart/Aware Homes and environmental control systems adds to a safe and comfortable home
environment for all people (Laberg, 2004). For individuals with impairments, the ability to control
and monitor home events helps to establish their independence.
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Assistive Technology and Computer Use
A growing number of ways to communicate information, education, and job related
computer-based applications are being developed for visually impaired or low vision individuals.
In order to interact with a computer, both input from the user and output from the computer need to
be understood. When designing an accessible computer for the visually impaired, developers must
address the different ways users may input information or retrieve the output from the computer.
The types of programs currently in existence for assisting computer users with reduced vision
include speech recognition, alternative keyboards, Braille devices, screen readers, and screen
magnifiers. These programs are evaluated by their adherence to the usability characteristics of
computer systems in Assistive Technology--flexibility, adaptability, customization to a user and/or
need, and specific applications or upgrades based on software instead of hardware (Cook &
Hussey, 2002). Cost effectiveness should also be considered to weigh the balance of features and
needed power. Current computer programs could be analyzed in terms of their usability and
utility. Such an analysis would help determine what would be useful to integrate, for example, a
potential thermostat system controlled by a computer system.
Ways to Receive Information
Braille devices are beneficial for translating visual text to a tactile Braille output.
However, while more effective than screen readers, Braille devices are only useful for computer
users who are familiar with Braille. Speech output is easily understood and can be relayed at a
faster rate than reading Braille. Computer programs have addressed synthesized speech output for
users with visual impairments, and can be used to assist users in navigation of a wide variety of
computer programs (e.g., programs to control a household appliance).
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Screen readers are software programs that work with the computer sound boards to
generate speech. Dolphin Supernova is an adaptable and customizable program that provides
screen magnification, speech output in more than 12 languages, as well as Braille output (Solutions
for Humans, 2004). Although only compatible on the Windows operating system, Supernova is a
versatile screen reader that combines many of the features that low vision users need in one
program. Supernova is very useful for computer navigation, but may not be very cost effective at
$1,195-$1,495. Its use may not be as common or reliable as JAWS, an extensive and customizable
screen reader that is slightly less pricey.
As claimed on their website, JAWS for Windows is the most popular screen reader
worldwide (Freedom Scientific, 2005). JAWS has the capability of assisting users with software
applications, including all standard Windows editions from 98 to XP, nonstandard Windows
applications, the Internet, and is available in 17 different languages. JAWS thereby connects its
visually impaired users to a wide array of visually displayed information. The software speech
synthesizer is also versatile in terms of Braille support, since JAWS can create refreshable Braille
display outputs in Grade 2 Braille (i.e., a more advanced Braille technique than letter-by-letter
Braille). Although Freedom Scientific has provided an extensive training package including
tutorials for introducing and installing JAWS (Freedom Scientific, 2005), the versatility,
flexibility, and reliability that the software package has on computer applications comes at a cost.
Specifically, the costs associated with this software are a minimum of $1,095 for JAWS
Professional (Windows NT/2000Pro/XPPro and 95/98/Me/XPHome) and $895 for JAWS Home
(Windows 95/98/Me & XP Home) (Freedom Scientific, 2005).
Other screen readers are available for download and installation in alternative operating
systems including Linux (Linux Accessibility HOWTO). Although free of charge, the programs
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require the user to reconfigure and write scripts to install the application, thus not as easily
customizable for a user or his or her needs. The quality of performance of these screen readers
may not be ideal and the additional features seem limited.
FreedomBox is also popular in the visually impaired community, as most of the people that
we interviewed use both JAWS and FreedomBox. FreedomBox is a “voice-controlled Internet
access device” (Serotek Corp., 2005) that uses speech recognition to allow users control over their
personal computer via voice command. FreedomBox also provides speech output and comes
either as software to install or in a more portable and flexible form. The FreedomBox Pass Key is
a credit card sized compact disc that can be transported easily and inserted in any computer to give
access to the Internet via direct voice command and through a screen reader. The Key to Freedom
performs the same functions as mentioned previously by accessing the FreedomBox Network, but
is memory stick sized and USB compatible. The FreedomBox Surfboard again provides the same
Internet access as the other FreedomBox products but is an entire computer condensed to the size
of a keyboard. The Surfboard comes with Windows operating system and allows users to attach
additional devices (e.g., mouse, monitor, printer). The increased portability of FreedomBox
devices coupled with the power of being able to use voice commands and a screen reader makes
the products popular with the visually impaired.
In addition to direct human-computer communication programs, users with reduced visual
capabilities may need assistance to navigate within a computer system. Screen magnifiers are
useful if low vision users need to view information on their computer screen at a larger size or
sharper contrast. Screen magnifiers vary in cost from free, included in the installed operating
system, to $545 depending on what functions the user needs (Freedom Scientific, 2005).
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Choosing a general design approach and strategy
Assistive Technology. It is very important for individuals with disabilities to have
accessible and affordable technology in order to participate in society, making the design process
critical for the success of a product. An assistive technology (AT) is any device, service, strategy,
or practice that is applied to improve the problems faced by people with disabilities (Cook &
Hussey, 2002). According to Public Law 100-407 of the Technical Assistance to the States Act, an
assistive technology device is, “Any item, piece of equipment or product system whether acquired
commercially off the shelf, modified, or customized that is used to increase, maintain or improve
functional capabilities of individuals with disabilities” (Cook & Hussey, 2002, p.5).
However, building upon these definitions, Cook and Hussey point out that it is important to
investigate the whole assistive technology system, which consists of the assistive technology
device, a human operator with a disability, and the environment in which the activity takes place
(2002). The AT world is also changing with new technology and models being developed, such as
accessibility application programming interface (API), open programming architecture, “just-intime accommodations”, and a “universal remote.” APIs specify how mainstream technology and
AT exchange information, such as standardizing how ATs and operating systems talk to each
other. Open programming architecture is common in the wireless world, allowing users to
download programs, ring tones, etc. from the wireless network directly to their cell phones
(Tobias, 2003). Another type of technology being developed is called “just-in-time
accommodations.” This technology will allow the device (e.g., an ATM) to download the exact
interface preferred by the user (e.g., the language the text is displayed in). An additional approach
to AT is the idea of a “universal remote” or “single interface device.” This approach creates a
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device tailored to the user to control or communicate with several different technologies using
standard data-communication protocols (e.g., infrared, RF, and Bluetooth) (Tobias, 2003).
Universal Design (UD). According to Ron Mace, UD is “the design of products and
environments to be usable by all people, to the greatest extent possible, without the need for
adaptation or specialized design” (as cited in North Carolina State University, 1997). Below are
the seven Principles of Universal Design “Copyright © 1997 NC State University, The Center for
Universal Design”:
(1) Equitable Use: The design is useful and marketable to people with diverse abilities.
(2) Flexibility in Use: The design accommodates a wide range of individual preferences and
abilities.
(3) Simple and Intuitive: Use of the design is easy to understand, regardless of the user's
experience, knowledge, language skills, or current concentration level.
(4) Perceptible Information: The design communicates necessary information effectively to
the user, regardless of ambient conditions or the user's sensory abilities.
(5) Tolerance for Error: The design minimizes hazards and the adverse consequences of
accidental or unintended actions.
(6) Low Physical Effort: The design can be used efficiently and comfortably and with a
minimum of fatigue.
(7) Size and Space for Approach and Use: Appropriate size and space is provided for
approach, reach, manipulation, and use regardless of user's body size, posture, or mobility
(Connell et al., 1997).
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Both UD and AT share the same purpose to “reduce the physical and attitudinal barriers
between people with and without disabilities” (North Carolina State University, 1997). However,
whereas AT attempts to meet the specific needs of individuals with disabilities, the goal of UD is
to simplify life and make technology and the environment more usable by people of all ages and
abilities (North Carolina State University, 1997; Tobias, 2003). Due to the expensive nature and
lack of information, ATs are only used by a small number of the intended users. As a result of this
weakness, companies may find a larger market for their products that use UD because of a larger
number of successful users (Tobias, 2003).
Another strong point of UD is that it may provide users with more input and output options,
allowing the users to select and operate the device in a manner that personally fits them. However,
Tobias also warns against a few specific design barriers to UD: the “needle in a haystack” barrier,
the “so close” barrier, and a support barrier. The “needle in a haystack” barrier is when there is an
overabundance of information or features on a given product, causing more accessibility and
usability problems than anticipated. The “so close” barrier involves products that have all of the
components needed for accessibility, but that are not arranged properly. The support barrier
occurs when an accessible technology does not have adequate implementation support for
accessibility (e.g., no one company owns Linux so there is no one to take responsibility for
accessibility) (Tobias, 2003).
Participatory Design. When designing and evaluating interactive computer systems, one
must take into account the user, the task, and the user’s total performance (Card, Moran, & Newell,
1980). According to Card et al., there are many different dimensions to performance: time, errors,
learning, functionality, recall, concentration, fatigue, and acceptability (1980). They also note that
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there is no single kind of task and that the users also vary among many dimensions: extent of
knowledge, knowledge of other systems, motor skills, technical ability, and experience (e.g.,
novice or expert). All of these complex dimensions must be taken into account in the design
process to increase the usability of the product (Card et al., 1980).
Since the users of technology often have different perspectives than the researchers or
designers of the system, it is important to involve the users in the design process. Designing
without the feedback of users may lead to the designer missing the perceived needs of the user
(Chambers, 1997, as cited in Davies, Marcella, McGrenere, & Purves, 2004). Kensing and MunkMadsen discuss two models of communication that are involved in design: a traditional model and
an alternative model (1993). In the traditional model, communication is created at one place (e.g.,
the developers’ office) and then brought to the users (e.g., a written system description). This type
of communication assumes that successful communication is determined by the developer’s ability
to form a precise message (Kensing & Munk-Madsen, 1993). However, the users’ needs may not
be met in this communication model because the designer did not include the user in the design
process. An alternative communication model is based on Participatory Design (PD) and is
created by people who interact. According to Kensing and Munk-Madsen, “successful
communication depends on the ability to establish situations in which mutual perturbations trigger
changes in the state of those involved, which in turn lead to structural congruence (social coupling)
among communicating partners” (1993, ¶ 16). PD assumes flawless communication among all
members of the design team as well as communication with the users of the system (Davies et al.,
2004; Kensing & Munk-Madsen, 1993).
To increase successful communication, designers using PD often employ techniques such
as prototyping, mapping, future workshops, and metaphorical design. When using paper
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prototypes, for example, the researcher and user walk through the design of the prototype together
and jointly modify the prototype. Through feedback from users about the system at this initial
stage, many usability problems are often discovered earlier in the design process (Davies et al.,
2004). PD is needed to acquire the knowledge required to develop a new system that will be easy
to use by the user population (Kensing & Munk-Madsen, 1993). Kensing and Munk-Madsen also
point out that knowledge of the task at hand, technological options, and the new system must be
developed and integrated for a successful design process. Providing users with technological
options are particularly important in PD because it stimulates their imagination and enables better
understanding of abstract descriptions of technical solutions (Kensing & Munk-Madsen, 1993).
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Building an Assistive Technology --- The Design Process
Target Users
The target users of our system are visually impaired and sighted individuals, age 18 and
older.
Getting started with a Needs Analysis
Many ATs have been designed to help the visually impaired in and around their household.
For our project we wanted to get a first hand view of the different ATs that are actually used by the
visually impaired and what tasks in the household still remain problematic. We decided to focus
on household tasks to provide the visually impaired with an increased level of independence in the
home environment. To gather information from the eventual users of the assistive technology
system we would build, we performed a Needs Analysis by informally interviewing some visually
impaired individuals.
Participants. Two visually impaired, adult females who volunteered their time and
opinions.
Method. To guide our research options, we created open ended survey questions to gain
information about problems people experience with household tasks (e.g., finding lost objects,
preparing meals). We chose to use a survey in form of an interview to learn more about the
potential users (e.g., the problems currently experienced) and the market (e.g., the solutions
currently available) before we designed a new assistive system. We collected data using the
following survey questions:
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(1) What are some common problems that you have on a daily basis around the house?
(2) How big/frequent of a problem is it?
(3) How do you currently deal with the problem? And what resources do you use for doing
so?
(4) Can you think of anything that would help you solve the problem?
(5) What kind of assistance would you like to see? (when, how, how often)
(6) How do you think this (mentioned) technology could assist you?
(7) What kind of benefits (drawbacks) do you see?
(8) What types of assistive technologies do you currently use?
(9) What problems do you have with these technologies?
Results. We found that the daily issues that were problematic occurred mostly with digital
appliances (i.e., any smooth surfaces or flat keys), air conditioning and heating control, preparing
food (i.e., reading labels on frozen food, baking instructions), setting the stove settings, and having
numerous code lists that keep track of how appliances are labeled. The ways that these problems
were dealt with depends partially on whether the interviewed live alone or not. Irrespective of this,
friends or relatives have to assist with the set up or installation for many appliances, and in many
cases, set the equipment so the visually impaired individual does not have to deal with it on a daily
basis. This could be problematic for people who live alone and want to adjust the settings on their
stove, washer and dryer, or thermostat.
Therefore, to make various devices more accessible to the visually impaired, the most
common solutions that our participants mentioned were either placing Braille labels, raised dot
indicators, on keys (e.g., on a remote controller) or using a bright marker to label certain settings
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on appliances (e.g., 350, 375, 425 degrees on the stove). Some over-the-counter appliances and
devices have been made, but are typically very expensive and not always functional.
According to the users that we interviewed, JAWS is unmatched in its performance as a
screen reader, which describes, albeit not warrants, the reason for its high cost. Furthermore,
although speech interaction for the visually impaired is beneficial in many ways, the people we
interviewed mentioned some problems with talking devices, particularly with their functionality.
Implication for design. The results of the needs analysis and the lack of an optimal solution
left us wanting to create a more reliable way of assisting individuals around the house. Our initial
idea was to create a system to control several appliances (e.g., stove, oven, microwave, washer,
and dryer). We thought of three possible design solution interfaces: 1. a universal remote, 2. a wall
display, and 3. a program that runs from the computer. These devices could give users added
independence of extended control. They could turn the washing machine on while sitting in the
living room, the heat off while cooking in the kitchen, or access the stove controls from the
computer in the bedroom. While possibly ideal in some situations, we realized that there are some
important issues which go along with this freedom of control. One could accidentally activate the
stove while trying to control the television, and with small children or pets in the home, this could
be a potentially dangerous situation. Some people have already difficulties keeping track of their
television remotes, but what if the universal remote was lost? Could the individual still use the
household appliances? On a simpler note, general design issues also exist when making a
universal system. Particularly, how can one fit all the features individuals would want on a single
interface but still be able to make it accessible? These issues lead us to decide against the
universal system control idea because of safety concerns.
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We revisited the suggestions and concerns made by the visually impaired individuals, and
decided to create a more accessible thermostat. Temperature control was something that both
participants we interviewed mentioned as having issues with and needed some degree of assistance
with. In fact, one of the participants mentioned that she had a friend set up her thermostat and has
not touched it since that friend left! The other participant reported that she has her husband deal
with the thermostat if she wants the temperature changed. We felt that these descriptions gave us
good reason to create an accessible thermostat that a visually impaired individual can use without
help.
Three different design alternatives
The design solutions we developed for the accessible thermostat were a talking thermostat,
a universal controlled thermostat on a wall mounted display, and a software or Internet-based
temperature controller. We first assessed the advantages of a talking thermostat as follows: people
with visual impairments (1) could interact with the device; (2) could access thermostat in the dark;
(3) could incorporate Braille with device; and (4) get extra feedback. The disadvantages of a
talking thermostat are that: (1) people could get annoyed with speech output; and (2) if the
environment is noisy it will be ineffective. Next, we assessed the advantages of a universal wall
mounted temperature controller such that: (1) it could be larger and easier to use than thermostat;
and (2) it could control other devices, such as lights and security system. We perceived the
disadvantages of a universal wall mounted display to be: (1) probably that it would be digital, so
people with visual impairments might have problems with it; (2) security/safety issues with
controlling multiple systems; (3) it would have to be specially installed. Lastly, we saw the
benefits of a software-based temperature controller such that a visually impaired person: (1) would
not have to walk to the thermostat; (2) would not need to search for the control (and therefore
23
cannot lose it); (3) could upload it to and access it from any computer; (4) it would make use of
already existing computer AT (e.g., JAWS, Freedom Box); (5) it could be used by many people of
various disabilities or people without disabilities; and (6) it could be supplementary to an on-thewall unit. On the other hand, a software-based temperature controller would require: (1) computer
access; and (2) possibly needed internet access. After assessing the pros and cons of all of the
systems, we decided to do some more research into devices similar to these design alternatives.
Existing solutions and implications for our design
After initial research into current solutions, we found that a talking thermostat already
exists, complete with a remote control and auditory feedback (T² RERC). This system was
designed with usability testing for a wide population of disabled people including older adults in
addition to people with motor and vision impairments. The thermostat gives visual, auditory, and
tactile feedback. Through user-centered design testing, the thermostat claims to optimize
accessibility, visibility, and intuitive use. Although the projected price of the system is not too
high at $99, consumers would have to buy an entire new system, which seems to be the only
downside of this accessible thermostat. Even though this system is still being researched and has
not actually been produced yet, its design seems solid enough to overlap with many of our ideas.
Therefore we decided to narrow our design solution to a software or Internet-based thermostat
system, which was not addressed by T² RERC.
The advantages to such an Internet-based thermostat system would be the added flexibility
to any user of the system, not only the visually impaired. The system could also be accessed from
anywhere (i.e., home, work, or while on vacation). Users would not have to walk up to the
thermostat or do not have to worry about potentially losing the remote control. The software
would be such that any computer could run the program, and could make use of existing computer
24
assistive technology such as JAWS and Freedom Box screen readers. Some constraints with this
solution are that users would need access to a computer and possibly to the Internet. Familiarity
with both would be a plus.
Alas, we discovered that a temperature control system that can be accessed from any
computer is already in existence in the market (HomeTech Solutions, 2005). The Proliphix
Network Thermostats can be accessed anywhere with an Internet connection and can control
multiple environmental monitoring systems (e.g., lights and security) besides temperature.
However, there are some huge accessibility problems with this thermostat. The complicated
system takes three screens to get to the temperature control part of the wall thermometer, and it
provides no auditory feedback. Furthermore, the web-based control interface is almost a mess
with complicated labeling, small font size, and non-optimal contrast. User-centered design was
not used according to the information provided on the website, much less designed with visually
impaired individuals in mind. In addition, the system requires a new installation of a wall mounted
thermostat. This brings the total price of the Internet-based thermostat to be $299.95 each.
The functionality and flexibility of an accessible thermostat should be able to be enjoyed
by the general population as well as the disabled population. This would help bring the price
down, while still benefiting a special group. The group in this case is the visually impaired, and in
order to prototype an accessible and more affordable temperature control system, we decided to
ask once again for their input in designing an Internet-based thermostat. Additionally to the
participatory design we revisited important user characteristics, performed a task analysis, and
looked at issues related to social and technical context.
25
Important User Characteristics (revisited)
Users must have access to a computer and the internet. We assume a prerequisite
understanding of a general thermostat system. Users will know what a thermostat is, how to
change the temperature, how to switch between HEAT and COOL, and how to turn off the system.
Users may have an understanding of how the thermostat program works, but this knowledge is not
required to use our web-based thermostat system. We also assume that our users are familiar with
using the internet and how to perform basic functions on a computer, such as how to install and run
a program. Physically, we are assuming that users are able to use a computer, with or without
assistive technologies.
Task Analysis
User Task Characteristics. The tasks performed by users can be divided into several
groups: visual/auditory perception, cognitive understanding/decision making, and motor skills. All
the subtasks involved with turning the system on and off involve visual/auditory perception and
motor skills. Changing the temperature involves: the sensory perception of the current
temperature; the minor cognitive choice of how much colder or warmer to set the temperature; the
understanding of what button/slider/switch to use to change the temperature; and the motor skills
involved in activating or moving this button/slider/switch. Programming the thermostat involves:
the sensory perception of the program menu; the cognitive choice of deciding what days, times,
and temperatures to set for the program; and the cognitive choice of how to start or activate the
program.
Environment Task Characteristics. The important characteristics of the task environment
will vary depending on the users personal preferences. The environment can be in the user’s home
26
and/or office. The environment will have a computer, which may have a screen reader or screen
magnifier if the user is visually impaired. The lighting around the computer may vary from
completely off (especially if the person is visually impaired) to bright indoor lighting.
Temperature would be controlled by the user to be a comfortable level (which is the whole point of
the project!). The task of accessing the thermostat on a computer can be performed alone or with
people around (e.g., at work), potentially creating a social and interactive work environment. A
noisy environment is grounds for attention diversion and loss of memory in regards to
programming the thermostat. These characteristics of the environment will be taken into
consideration when designing the system.
27
Higher Level Task Analysis
Access system
Display system status
Determine system status
Exit
Off
Heat
Change system status
Cool
Exit
Air
only
Set temperature
Auto
Change temperature
Program thermostat
Exit
Figure 3. Higher level task analysis for setting a thermostat.
Detailed Task Analysis/Function Allocation
1.0. Set COOL mode temperature
1.0.1. Access system (human)
1.0.2. Display system status (machine)
1.0.3. Determine system status (human)
1.0.3.1. If COOL on, Go To 1.0.5. (human)
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1.0.3.2. If not, Go To 1.0.4. (human)
1.0.4. Turn COOL on (human)
1.0.5. Display current temperature (machine)
1.0.6. Determine current temperature (human)
1.0.6.1. If temperature setting acceptable, Go To 1.0.7. (human)
1.0.6.2. If not, change temperature (human)
1.0.7. COOL mode running (machine)
2.0. Set HEAT mode temperature
2.0.1. Access system (human)
2.0.2. Display system status (machine)
2.0.3. Determine system status (human)
2.0.3.1. If HEAT on, Go To 2.0.5. (human)
2.0.3.2. If not, Go To 2.0.4. (human)
2.0.4. Turn HEAT on (human)
2.0.5. Display current temperature (machine)
2.0.6. Determine current temperature (human)
2.0.6.1. If temperature setting acceptable, Go To 2.0.7. (human)
2.0.6.2. If not, change temperature (human)
2.0.7. HEAT mode running (machine)
3.0. Turn system off
3.0.1. Access system (human)
3.0.2. Display system status (machine)
3.0.3. Determine system status (human)
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3.0.3.1. If thermostat off, Go To 3.0.5. (human)
3.0.3.2. If not, Go To 3.0.4. (human)
3.0.4. Turn system off (human)
3.0.5. System off (machine)
4.0. Program system
4.0.1. Access system (human)
4.0.2. Set program (human-machine)
4.0.2.1. Select day (human)
4.0.2.2. Select temperature (human)
4.0.2.3. Display chosen settings (machine)
4.0.2.4. Confirm chosen settings (human)
4.0.2.4.1. If program settings complete, Go To 4.0.3. (human)
4.0.2.4.1. If not, Go To 4.0.2.1. (human)
4.0.3. Run program (human-machine)
This is a task analysis/function allocation for the thermostat system. To read this task
analysis, you start at 1.0 and move in numerical order down the list, unless instructed to skip to a
particular number. Everything not in the parentheses is the task needed to perform the higher level
goal indicated by either 1.0, 2.0, 3.0, or 4.0. The word(s) in parentheses informs who/what will be
performing that task. "Human" means that the user performs that action, "machine" means the
system does, and "human-machine" means both the user and the system performs the task. After
further analyses, a function reallocation may need to be done to see if the human or machine can
do certain tasks safer, more efficiently, or better than currently listed.
30
Social and Technical Context. External contexts that could affect our system include the
influence of both social and technical factors. Social factors include individual characteristics such
as age and willingness to try an alternative method for changing one’s thermostat. Reluctance to
try new technology may hurt the acceptance of the new system in society. However, one social
factor that may help in the success of our system is the increasing amount of travel that people are
doing. Being able to remotely access one’s thermostat while on vacation is a good selling point for
our system.
The technical context with the web-based system has to do with the basic understanding of
how thermostats work, how to operate a computer, and how use the internet. Past familiarity with
turning the thermostat system on and off, changing the temperature, programming the thermostat,
and operating the various controls will be helpful procedural knowledge when wanting to use our
web-based thermostat control system. More general background knowledge and familiarity with
other technical systems such as computers and the internet is required in order to operate the
system. For users who are visually impaired, experience with a screen reader or screen magnifier
is necessary to interact with the system on the computer. Due to the added interaction with a
computer, our design must consider users of all technical background knowledge areas to ensure
usability with our system. Our system must also be accessible to screen readers if visually
impaired users are to access our online thermostat.
Participatory Design
After we decided to focus on the software-based thermostat, we further involved potential
users in our participatory design process by conducting a second round of interviews via telephone.
31
Participants. Three visually impaired, adult females who volunteered their time and
opinions.
Method. We asked three visually impaired women via telephone the following general
questions about their current thermostat use:
(1) What features of your thermostat do you use?
(2) What features of you thermostat do you not use?
(3) How much would you be willing to pay to make your current thermostat accessible?
(4) Do you use a screen reader?
(5) If so, what brand(s) do you use?
(6) Would you be interested in some sort of software or website that would allow you to
interact with your thermostat from your computer?
After these general questions, we explained our project using the following script: “For our
project for our Assistive Technology class, we decided to design a computer software program to
control a thermostat. This program would consist of a website you can long onto or a CD that you
can load onto multiple computers (e.g., work and home computers) that would allow you to
monitor and change the current temperature of your house. This would also allow you to set the
temperature from work so that when you arrive home the house is a comfortable temperature for
you. Given this program….”
We then asked the participants the following questions about how they would design a
web-based thermostats:
(7) How would you arrange a webpage to help you control your thermostat?
- Single column?
32
- Two columns?
- Single Page?
- Multiple Pages?
- Functions—heat on/off, cooling on/off, set heat/cooling, current temperature reading,
current thermostat setting, fan on/off, program
(8) How would you like the functions/buttons labeled?
- Heat, heater, cold, cool, A/C, etc.
- Current temperature (what air temperature is), current thermostat setting (what
thermostat temperature is set for)
(9) What controls would you like?
- General off button vs. heat/cold off buttons?
- General set temperature button vs. set heat/cold temperatures buttons?
(10) How would you like to control the input of temperature?
- Up/Down Arrows?
- Numerical Value Input?
(11) Would you use the program feature?
(12) Would you want to access the temperature from a location away from the home (ex.
work, travel)?
(13) Would you be interested in this sort of technology for other devices such as:
- Washer/Dryer?
- Lights?
- Security Systems?
- Dishwasher?
33
Table 1. Results of the second interviews
Question
Number
1
Participant A
Responses
Heat and A/C, push
buttons with tactile
feedback, set hold
button
Participant B Responses
Participant C Responses
On/off, Heat/ cool switch,
Run (someone else set the
program up), Up and
down arrows to adjust
temp
2
program
Everything else (don’t
know what cause she
doesn’t use them),
Program button
3
no more than what it
cost, tired of
spending money for
technology
No more than $50
4
Freedom box at home Freedom box at home and
and JAWS at work
JAWS at work and home
No, wouldn’t use it,
Yes
not a computer
person
Uses all of the features, Does
not have a programmable one,
but requested a manual
thermostat, It has a slider like
in the old days, Lever on the
right that can slide up for the
temperature to rise, If you
slide it to the left (=heat), the
right (=cold), the middle
(=off). And it has an auto,
Also has a fan only mode,
There is programmable
thermostat that talks, but it’s
not a high priority for her, Put
marks by the temperatures
(70, 80), bubble dots.
Uses all of them because it’s
very simple, She dealt with a
programmable one, but that
seems to have not been a good
experience, Problem was that
if you reset it, you need a
sighted person to set it up.
Thought about the talking
thermostat. A friend has
purchased one that wasn’t
compatible with house, and
the friend resold it, They cost
around 100$ or more than
100$. She wouldn’t be willing
to pay that much.
JAWS for Windows, Freedom
Box
Interesting concept! Very
doable!
5
34
6
*
7
*
8
*
9
*
10
11
*
*
12
If it was a remote,
but not with a
computer
Single column … a screen
reader reads everything off in
a running order. If had 2
columns, then she wouldn’t
know … then corrects herself
… because screen reader will
say ‘column 1, column 2’ …
but will still put everything in
a running order,
prefers everything on one
page, grouped in sections, for
example all cold [controls] in
one section, all heat in one
section etc, plus programming
and making changes online
use tabs to get to
Heat … basically what they
heat/cool, then adjust with are currently labeled, would
up and down arrows
like to have these functions,
how they are normally labeled
Heat, A/C, Off, “Current
Prefers a general off button
Temperature is:”,
because you don’t have heat
“Current Thermostat
and cold running at the same
setting is:”
time, Prefers a general set
temperature button and better
if scroll up and down, If have
set heat/cold … would suggest
that had to enter both.
General Off button,
Yes to arrows. JAWS has a
General set temp button
combo box for arrows up or
down, Numerical input good
option to have
Both types of input
yes
yes
Would love to … would be
good for anybody blind or
sighted, Travel is what popped
into her mind right away
Yes to all
Interesting idea. Doesn’t know
about washer and dryer. They
have turn dials, But she could
see it for: (1) porch lights (she
turns them on in the evening
and sometimes forgets to turn
them off in the morning), (2)
alarm systems, (3) anything
that can hook up to the
network, (4) internal lights
Maybe easier with a
single column, Maybe
double columns would
work too, Single page
probably, do not use
multiple pages
35
(turn them on when traveling
so it looks like someone is at
home), (5) maybe stove – to
set timer, laughed when she
heard dishwasher 
Please note that the * indicates missing data. After Participant A responded that she would
not use a computer-based thermostat system, the rest of the questions, except for the last one, were
skipped.
Implication for design. From the second round of interviews we learned that the visually
impaired participants wanted a single column on one page. They also wanted grouped sections
(e.g., all cold controls in one section) and to keep the current labels on their thermostats (e.g.,
HEAT and COOL). The participants suggested a general OFF button and a general Set
Temperature button. Both combo boxes (scroll up and down) and numerical value input seemed to
be the preferred methods of inputting choices on the web applet. We used these suggestions when
designing our three web-based prototypes.
36
Creating and evaluating the prototype
Information about controls and displays to consider
A control is an input device or a way to select and execute responses for a device (e.g.,
buttons, sliders, switches) (Cook & Hussey, 2002; Wickens, Gordon, & Liu, 1998). The spatial
characteristics of controls and how they relate to the user must be considered in the design process
to increase usability. The four spatial characteristics of controls are: (1) overall physical size,
shape, and weight; (2) number of available targets contained within the control interface; (3) size
of each target; and (4) spacing between targets (Cook & Hussey, 2002). Cook and Hussey also
point out that the activation characteristics of a control interface—method of activation, effort,
displacement, flexibility, durability, maintainability—should also be considered when designing an
interface, especially if users with disabilities will be using the device (2002). If a user is limited in
his ability to input information into the control, then the system has failed and cannot be used,
which is why the physical dimensions and layout of a control must be thoroughly researched
before completing the design.
A display is an output device or a way to perceive the relevant system variables and
facilitate processing of information (e.g., voice output, monitors, paper printouts) (Cook & Hussey,
2002; Wickens, Gordon, & Liu, 1998). Wickens et al. discuss the physical dimensions of displays
that can be manipulated by designers: location, color, dimensionality, motion, intensity, coding,
modality, and what to display (1998). It is critical that users are able to gather and understand
information from a display or else the design has failed, regardless of the success of the control
design. To increase the success of the display, Wickens et al. layout 13 design principles for
displays that should be considered throughout the design process:
37
(1) Avoid absolute judgment limits—avoid judgments based on a single sensory variable
like color or size.
(2) Top-down processing—expectation and past experiences will affect how people
perceive and interpret signals.
(3) Redundancy gain—present alternative physical forms for information.
(4) Discriminability—similarity causes confusion.
(5) Principle of pictorial realism—display should look like the variable it represents.
(6) Principle of the moving part—moving elements should move in a spatial pattern and
direction compatible with user’s mental model.
(7) Ecological interface design—display has close correspondence with environment being
displayed.
(8) Minimizing information access cost—minimize time and effort to move selective
attention between display locations.
(9) Proximity compatibility principle—mentally integrate two or more sources of
information for the same task.
(10) Principle of multiple resources—divide information across resources, such as present
visual and auditory information concurrently.
(11) Principle of predictive aiding—remove resource demanding cognitive tasks with
perceptual tasks.
(12) Principle of knowledge in the world—placing explicit visible reminders or statements
of what is to be done at the time; and
(13) Principle of consistency—design displays consistent with other similar displays.
(1998)
38
There are many factors, perceptual and mental, involved in the design of controls and
displays that need to be considered, including information about the users of the system and the
system as a whole as we already outlined earlier.
Creating the prototypes
We created three prototyped websites for our participants to evaluate, trying to incorporate
as much user feedback as possible, while also considering the control and display issues outlined
earlier. The prototypes were created using Macromedia Dreamweaver and through direct
manipulation of HTML. Some JavaScript was used so that the websites could provide feedback.
All three websites had the system controls (heat, cool, off) and the fan controls (on, auto) grouped
separately. This was modeled after how many current thermostats use these controls so our
prototypes would be consistent with user experience and expectations.
As the system was being developed, it was checked for its screen reading accessibility by
using Microsoft Narrator. Because Narrator is not what the participants used to navigate through
the virtual thermostat (all used JAWS instead), there were some problems that arose during the
usability testing. We also tested our websites in various online W3C validation services, such as
http://validator.w3.org/ and http://webxact.watchfire.com/ . However, our websites were not W3C
compliant according to these validation services, but we did not have the skills to make it
compliant with these rules.
The prototypes differed in the way in which the user interacts with each of these controls.
The first website used drop-down menus (i.e., combo-boxes), the second website used radio
buttons and combo-boxes, and the third website used clickable links (see Appendix A, B, and C for
screenshots of each website version). The method for changing the temperature on all three sites
was controlled by combo-boxes and/or numerical input. The reason for this was that with more
39
than 40 temperatures to choose from, radio buttons did not seem a sensible option. All three
websites offered users a way to set a program that the thermostat could be instructed to run. Two
of the websites offered participants the option to set the program to a specific temperature. The
third website offered users a way to set a program so that between a range of times the system
would be set to a specific temperature. Two of the three websites were fully functional while one
website was only a mockup. The websites employed labels to help the blind users recognize the
different elements when read aloud to them by their screen readers.
Evaluating the prototypes
Participants. We tested the prototypes with subject matter experts for both sighted as well
as visually impaired people. The subject matter experts for sighted were five graduate students
enrolled in the engineering psychology program at the School of Psychology at the Georgia
Institute of Technology. The graduate students (4 males and 1 female) were between 25 and 30
years old. The visually impaired participants were all female and between the age of 48 and 54
years old. All three of the visually impaired participants required screen readers while using the
computer. No compensation was being provided for participating, but participants were thanked
for their time and effort.
Materials. We used the three websites described above to test participants on various
computers, ranging from PCs with Windows to Macintoshes with OSX. The three visually
impaired participants used their own computers with their own JAWS screen reading software.
We recorded the data (task completion, errors, problems, and comments) on the two attached task
sheets (see Tables 2 and 3). The evaluation forms contained the questions we asked participants
40
for each website prototype as well as spaces to record what we observed. See Table 4 for the form
we used for the exit interview questions and the comments from the third website.
Procedure. Testing for the subject matter experts took place at their work place. For
graduate students this was the School of Psychology at Georgia Tech. Two of the three visually
impaired participants were tested at the Center for the Visually Impaired in Atlanta, and one
visually impaired participant was tested at the Food and Drug Administration building in Atlanta.
Graduate students were tested by one experimenter. Due to the fast pace of screen readers and
expected difficulties for one experimenter to note all important information, at least two
experimenters were present when testing visually impaired subject matter experts.
First, consent was obtained from the participants. For graduate students this meant that the
participant read the consent form and signed it. This was followed by the experimenter signing the
form. The consent form was read to visually impaired subject matter experts in the presence of a
witness (other than the experimenters). The participant, witness, and experimenter all signed the
form.
Next, participants were given a general overview of the experiment. For each of the three
web pages, participants were first given a few minutes to familiarize themselves with layout and
content. After this familiarization phase, participants were instructed to perform a set of tasks such
as obtaining and changing the current temperature to a specific number and setting the weekday or
weekend schedule (see Tables 2 and 3 for specific tasks). Experimenters noted the steps and
problems in completing these tasks as well as any comments made.
After completing the tasks and before moving to the next web page, participants were
asked what they liked and disliked about the layout of the current web page. After evaluating all
three web pages, participants were asked to compare and provide feedback on all three web pages.
41
Results of prototype evaluation – sighted participants
The following comprises a summary of the results. Please see Tables 5-10 for specific
results of the evaluation for sighted and visually impaired adults.
Mental model and system image
For all three websites, the graduate students had conceptual problems, irrespective of the
layout of the website. There were difficulties understanding how the possible status of the system
(on, off, heat, and cool) interacts with the possible settings of the fan (on, off, or auto). Graduate
students also voiced having the same problems with the physical thermostats outside the
experiment. For example, they did not really know whether the system would still work when it
was set to cool or heat, but the fan was off. Similarly, what would happen if the system was set to
off, but the fan was on?
When asked to set the system to heat (or cool), this unclear system image lead two of the
five graduate students to adjust the temperature additionally to setting the system to heat (or cool,
respectively) just to ensure that the system was doing the intended action. A related concern was
whether the temperature was activated when the fan was turned on.
Irrespective of the layout of the website, the five graduate students used all kinds of
system/fan combinations to turn on the heat or the cool (see Table 11 below). This supports the
idea that participants did not have a clear system image or suggests that there are multiple routes to
achieve the goal.
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System setting (heat/cool/off)
Fan setting (on/auto)
Temperature
Heat or Cool
On
unchanged
Heat or Cool
Auto
unchanged
Heat or Cool
not clicked
unchanged
Heat
not clicked
change temperature
Table 11. System/fan combinations made by graduate students when setting the thermostat.
Feedback
A second issue for the graduate students across websites was confusion over which of the
settings would take precedence: the current settings or the programmed ones. A related issue was
being unclear about whether adjusting the current or programmed setting was sufficient to activate
them, or if it was necessary to click the ‘run program’ button. Possibly due to this confusion, the
graduate students also commented across websites that they would like to gain more feedback on
the current system status. The students looked at the combo boxes to verify that the correct
number or time was chosen.
Scheduling
Although the graduate students overall like the idea of programming the temperature, the
rational for choosing one setting for the whole week (Monday through Friday) while having
separate settings for Saturday and Sunday was unclear. To participants, a distinction between
‘weekdays’ and ‘weekend’ would have made more sense or being able to choose settings for each
individual day.
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Website 1 specific results (combo boxes, time range)
The graduate students liked this layout because it was clear, uncluttered, and for its
programming functionality. The amount of scrolling involved was perceived negatively and
participants would like to see current temperature and set temperature in closer physical proximity.
Website 2 specific results (radio buttons, 1 time)
The feedback on the radio buttons was mixed. Some students liked that all options were
immediate visible, whereas others disliked it because it produced clutter and because radio buttons
can be accidentally activated. Furthermore, radio buttons constitute smaller targets and require
more precise navigation. Graduate students liked about this website that it was compact and easier
to be programmed, however, some students disliked that they could not set a time range.
Website 3 specific results (links, 1 time)
The links were perceived to be easier targets, but do suggest that they will go to another
page. Graduate students were confused by the inconsistency between the upper portion of this
layout where a link indicated a change in the system’s settings and the lower portion of the
webpage where the visual format (underlining) indicating a link was used as a format for a header.
Specific to this layout was the lack of visual separation between the system and fan
settings. It suggested a choice out of five, when in fact there were two choices to be made: one out
of three for the system, and one out of two for the fan. Too many similar words for these five lines
made it hard to decipher the actual meaning of the links – or to glean the difference between the
five links.
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Summary for graduate students
Overall, three graduate students like the first website better because of the clearer
differentiation of the functions and the organization of the categories. Two students like the
second one better because the options were more visible, showing them all at once, and because it
involved less scrolling. The use of radio buttons was equally divided. All graduate students would
have liked more feedback on the current system status and receiving some form of
acknowledgement that the changes in temperature and program were accepted. The graduate
students completed the tasks very quickly, although sometimes with different settings. When
asked at the end, if the participants could see themselves using the web to control their thermostat
at home, most graduate students answers yes.
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Results of prototype evaluation – visually impaired participants
Website 1 specific results (combo boxes, time range)
Participants found the Fan mode placement confusing, resulting in navigating up and down
the pages several times before finding the correct mode (e.g., COOL). The screen readers also
showed that we had mislabeled some of the functions in the website. For example, in the program
function, the times are set “from” Time A “to” Time B. However, the “to” was mislabeled and
said “from” instead, which caused some confusion. Another example of the mislabeling was also
in the program setting. On the Saturday schedule, it read “weekday” instead “Saturday.” Despite
the mislabeling, 26 out of 27 tasks (9 tasks x3 participants) were completed successfully. The
perceived advantages of this website were: (1) accessible to screen readers (one participant said,
"Well done for accessibility!”); (2) it was simple and intuitive despite the labeling issues; and (3)
participants loved the combo boxes and the ability to type in the degrees into the boxes. The only
mentioned drawback of the website was the mislabeling issue, although participants said the site
was intuitive enough to figure out despite incorrect labeling.
Website 2 specific results (radio buttons, 1 time)
The problems that participants experienced with the second website were more issues
related to functionality. The forms mode of JAWS was not working with the radio buttons, so the
radio buttons could not be accessed properly. Like the first website, there were also some labeling
issues, especially with the radio buttons. The radio buttons were labeled “OFF 1 out of 3”, but all
of the buttons were shifted down one and did not line up with the respective wording. What
participants did like about this website was its simple layout. They also like the combo boxes that
were still present for setting the temperature and in the programming section. Participants also
46
liked how the radio buttons were after the word options, which was easier to hear read to them by
JAWS. However, one participant said that the website. “Doesn’t make a whole lot of sense.”
Overall, they thought the second version was more difficult to use.
Website 3 specific results (links, 1 time)
The third website was confusing because the links did not lead to another page. Although
one participant thought this was an excellent feature, she added that the presence of links may
deter people who may not want to leave the page, especially if they are not familiar with JAWS.
This would affect the acceptability of the system. One of the participants who was not as
technologically oriented as the others felt that the links were an easier way to tab through the
options, especially since she was not used to radio buttons and combo boxes. Although they
seemed easier for one participant, the others still raved about the combo-boxes in the first version
of the thermostat website.
Summary for visually impaired participants
Overall, two of the visually impaired participants strongly preferred first version. They felt
that the combo boxes were simple and easy to use. One person preferred the third version
followed by first. This preference may be dependent upon familiarity with computers and JAWS,
which was a comment from the participant herself. She had a lot of trouble with many of the tasks
because she was not familiar with JAWS and, therefore, felt that the links were most
straightforward. However, all three participants liked the program function of the first website,
with the range of temperatures to set. When asked if the participants could see themselves using
the web to control their thermostat at home, one person responded, “It would be cool!” They felt it
was reliable and could be used with any type of thermostat. Another participant responded
47
“Absolutely! Send it to me!” This person would also use it to control other systems, such as her
security system and outside lights.
48
Discussion/Recommendations
General Website Problems/Recommendations
First of all, corrections need to be made to the labels and links that caused problems with
the screen readers. Also, more feedback needs to be provided with all of the websites. Both
sighted and visually impaired participants requested to have feedback on the current system status
such as if the system was on HEAT, COOL, or OFF. Sighted participants also wanted the current
temperature and set temperature choices closer to each other so they did not have to scroll up to
find the current temperature. In addition, a lot of the participants (both sighted and visually
impaired) had problems with the fan mode in all of the websites and how it interacts with the
various system functions. The location of the fan mode on the interface needs to be carefully
thought about in order to place it in a location that people feel is intuitive. One suggestion that we
got from the presentation was to have fan in AUTO mode as a default, but to have a FAN option
grouped with HEAT, COOL, and OFF. This way, users might understand that there was the
option to only have the fan running.
Another issue with all of the websites is the program function. Not all thermostats have a
program mode and people may not be familiar with its functionality. However, the people who
currently have a programmable thermostat and use it will better understand what it does.
However, there is the problem on how to design the layout and labeling of the program. Our
participants (sighted as well as visually impaired) were confused or not satisfied with the “Set
Program” and “Run Program” buttons/links. Currently, we have the “Set Program” heading
(which is not a link) above the program and the “Run Program” button at the bottom of the
program. One possible way to redesign this layout is to move the “Run Program” button next to
49
the “Set Program” button. It might also be a good idea to actually make “Set Program” a working
button that you have to press in order to change anything in the program. Changing the
functionality in this matter could decrease confusion about the layout of the program, but also
decrease the chance of accidental activation.
Another problem with the program that both participant groups had was the choice of
labeling the days. Some participants did not like how the days were grouped by weekdays,
Saturday, and Sunday. One way we could change this is to have a setting for weekday
temperatures and a separate setting for weekend temperatures, which would also have the benefit
of saving physical space. Another possibility is to provide the ability of setting each day of the
week separately. Depending on how this is implemented, it could easily take up more space, cause
more scrolling, and result in more clutter. Yet a different option is to have a general weekday
setting and add a link/button to click that opens up the possibility of setting specific days during
the week. We could program the website to not allow a general weekday setting once you make
changes on specific days. This way the user would not have to scroll or set every day if that was
not desired, but the option was at least available.
Participants (sighted as well as visually impaired) also wanted to see the current
temperature setting closer to “Set temperature” option in all three websites. The scrolling up to the
top of the page to obtain the current temperature was not liked by the participants. One participant
mentioned that we should use the capabilities of the software and give users only the options that
make sense at a time. For example, if the user has COOL mode on, then the Fan mode should not
appear as a choice. This would help reduce clutter, but could cause problems if the person is not
sure what they do want to actually happened. Something else that we discovered is that the system
model needs to match the users’ mental models. These mental models are based on prior
50
experience with thermostats and could play a role as to how easy the website is for the user. This
mismatch of mental and system models was especially evident in the Fan and program issues
mentioned above. We may need to rework the system model. Other than the problems specific to
the screen readers (i.e., mislabeling and issues with forms mode), the graduate students and
visually impaired participants had similar issues with the websites, indicating that the websites are
usable by both populations.
Website #1 (combo boxes)
Overall, people appeared to like the first website the best. They felt it was clear,
uncluttered, intuitive, easy to read, and the choice of scrolling in the combo boxes or typing in the
first number to jump to that group of numbers. The visually impaired people who were familiar
with combo boxes loved the functionality of the boxes and ease that JAWS reads them. Both the
sighted and visually impaired participants liked the range of times available on the program
function of this website better than the other websites.
Website #2 (radio buttons)
Although more people like the first website the best, some people in both groups did prefer
the second website with the radio buttons. They felt that they could see all of the targets at once
and less scrolling was needed. However, the radio buttons are small targets and could cause
accidental activation.
51
Website #3 (links)
The third website with the links was generally not very well liked by all participants. We
do feel that this layout has potential to be a good website, especially if we change the links to
buttons and decrease the number of words for the different functionalities.
52
What We’ve Learned
Firstly, we discovered that prototyping while learning a computer language is a trying task.
While none of us specifically has skills in coding, one group member was taking a class that taught
Dreamweaver and general web design concepts, which we found to be helpful for this project. If
we had access to a web designer, we could have spent more time on the evaluation process, include
iterations of our design. Despite the resources taken from the above-mentioned class, there
remained numerous questions that stood in the way of creating three fully functional versions of
our website. We had to deal with our websites complying with accessibility guidelines and JAWS
functionality, as well as make sure they were designed in the way the three visually impaired
people with spoke with suggested. Getting everything right in this sense meant fixing
programming errors as we went along and tested our prototypes with the visually impaired. If
there were to be future versions of the Virtual Thermostat system, some of these malfunctions with
coding would be fixed to allow for better usability testing. In the mean time, we recognize that
adequately mocking-up a website takes time and experience.
Along with the amount of time it takes to learn a new computer language, we also now
recognize the need to continuously test the prototype with the kind of assistive technology the
visually impaired use to access it with. These problems would most likely have been curtailed had
we been testing the mock-up with JAWS instead of Narrator.
Thirdly, we learned that people with disabilities do not want to spend a lot more money on
assistive technology than one would pay for the normal technology. This could be because they
typically need or want several different assistive technologies, and with the cost of each AT being
high, money definitely becomes an issue. The visually impaired individuals that we spoke with
mentioned owning devices that were “accessible,” such as a talking caller ID or talking
53
thermometer, but do not even work in basic functionality. Even if an accessible system does work,
a high price tag could deter people from purchasing it. Therefore, we learned to design a virtual
thermostat system that would appeal to any consumer, not just one with a disability. Implementing
universal design would keep the price of the system lower so it could be more competitive with
existing thermostats on the market.
Lastly, through this project we understood the hard task of designing to suit a user’s mental
model of an existing system while also considering the variety of mental models due to individual
differences. A truly usable virtual system will reflect an individual’s mental model of how such a
system operates in the real world. But what if there is no standard system model? This accounted
for the difference in opinions of how the thermostat should work according to the sited graduate
students. We can attempt to design under these considerations, but what if we also have to account
for the visually impaired individual’s mental model? This introduces more design considerations,
and it becomes difficult to produce a system that makes intuitive sense to every user. We strived
for a universally designed system concept by aiming to make the thermostat simple and easy to use
for every consumer (i.e., lots of white space, high contrast, large font, etc.). However, most of
these considerations would be fleshed out through multiple iterations of the design. Overall, we
learned it was important to allow for design iteration, along with user feedback, when designing a
system for any population, including the visually impaired.
54
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Appendix A – Screenshot of Website 1 (combo boxes, time range)
Note: above screenshot is not true to the actually displayed text size
59
Appendix B – Screenshot of Website 2 (radio buttons, 1 time)
Note: above screenshot is not true to the actually displayed text size
60
Appendix C – Screenshot of Website 3 (links, 1 time)
Note: above screenshot is not true to the actually displayed text size