Sensory devices: - Helen Hamlyn Centre - Royal College of Art

Sensory devices:
communication in domestic appliances to aid use by
older people
Helen Hamlyn Research Associate:
Bryn Griffiths
RCA Industrial Design Engineering
Research Partner:
Dyson Research
October 2000

i~design case studies
This is one of a series of inclusive design case
studies published as part of the i~design research
programme. These case studies document inclusive
design collaborations between the Helen Hamlyn
Centre (HHC) and industry and voluntary sector
partners, under the Helen Hamlyn Research
Associates programme. They also document the
results of the ‘Inclusive Design Challenge’, a
design competition co-ordinated by the Helen
Hamlyn Research Centre and the Design Business
Association.
i~design is a multi-centre collaborative research
programme funded by the Engineering and Physical
Sciences Research Council (EPSRC). The purpose
is to foster the adoption of inclusive design by
business decision makers and professional designers,
in particular by presenting the business case,
developing tools and techniques, and building
a network of researchers around the projects.
i~design partners
• The Helen Hamlyn Centre at the Royal College of
Art, London, is a centre for inclusive design, with
extensive contacts in industry and
design professions.
• The Engineering Design Centre at the University
of Cambridge has a strong reputation in
the improvement of design process and
development of design methodologies
to address specific issues.
• Applied Computing at the University of Dundee
develops information technology systems to
support older and disabled people.
• The HCI Group at the University of York has
a long history of inter-disciplinary research
in the area of user centred design arising from
collaboration between the departments of
Psychology and Computer Science.
• The Design Council inspires and enables the
basic use of design by business, education
and government to improve prosperity and
well-being.

Sensory devices:
communication in domestic appliances to aid use by
older people
Abstract
It is often the familiarity of everyday domestic appliances which obscures shortcomings in the
way they operate. The physical interfaces of such products as vacuum cleaners, kettles and
washing machines remain unchanged and unyielding to older users in particular, while newer
product categories afford much easier interaction. This applied research study investigates
new ways to communicate the product functions of Dyson vacuum cleaners to older users (Fig
8). More than a quarter of Dyson’s customers are aged 55 and over and through this project
Dyson Research has a new road map for future development of new features to aid older
users. Many of the findings are much more widely applicable. Product communication audits,
ethnographic and other research findings were mapped against a parallel investigation of
automotive interface issues to produce a set of guidelines for inclusive design. Such issues as
form, colour, orientation, consistency and commonality of features, signs and symbols, and
reassurance through other senses were mapped and used to help direct the design process. A
series of design proposals then showed how audio and textural sensory devices can be incorporated
to improve the ease of use of domestic appliances for all. Concepts include polymers,
which change colour when appliances get hot, sound reeds which emit audio signals and buttons
that deploy textural contrasts and vibration in use.
Keywords
Domestic appliances, vacuum cleaners, older users, inclusive design, sensory feedback,
physical product interface.
Project period
October 2000 - October 2001
Overview
Over recent years In many new product and
technology categories consumers have
seen much progress in the quality of both
physical and digital interaction as the idea of the
user interface has become more sophisticated. In
the domestic appliance industry, by comparison, a
reliance on instruction manuals, rather than intrinsic
design features, has resulted in everyday products
that do not communicate their operation to the user.
This problem has been compounded by domestic
appliance producers ignoring the needs of an ageing
population; it is older users in particular, with
a range of physical impairments, who require
the improved clarity of operation that benefits all.
As the population ages across the developed
world, the key role of everyday domestic
appliances to support in independent living for
older users becomes clearer. Figures for sensory
and physical impairment are set to becomes more
influential in the creation of products and
environments (Table 1).
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Sensory Devices | Bryn Griffiths
Numbers of people with physical and sensory impairment across Europe 2000
Number in millions
Poor vision 12
Reduced strength 22
Reduced co-ordination 12
Intellectually impaired 30
Table 1. European levels of physical and sensory impairment (source: Dr John Gill RNIB)
The overall objective of several strands of research
deployed in this project was to identify the critical
areas of performance in the interaction between
the user and appliance. Research focused on the
Dyson vacuum cleaner and formed the basis of an
inclusive design framework and other recommendations,
which would provide industry partner,
Dyson Research with a comprehensive guide to
specific and overall issues of inclusivity in its products.
As is customary in HHRC Research Associate
projects the one-year project was divided into four
stages:
Stage 1: Explore (October-December)
Stage 2: Focus (January- March)
Stage 3: Develop (April-June)
Stage 4: Deliver (July-September)
Methods
The four main stages were intended together identify
the critical areas on the vacuum cleaner where opportunity
for enhanced user understanding lay.
• A product communication audit, along with other
desk research carried out at Dyson Research identified
the information available to Dyson customers
at one step removed from the product: packaging,
graphics, instructions, advertising, point of sale, in
the media etc.
• Generic user scenarios identified potential older users
and the appliance-related problems and opportunities
they face.
• An investigation into interface issues in the automotive
industry was made to see how designers
enable complex information to be conveyed quickly
and effectively to users.
Product Audit
Generic User Scenarios
Critical Areas
Automotive Industry
Ethnographic Research
Figure 1. The separate sub-research phases feed into identification of the critical areas
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Sensory Devices | Bryn Griffiths
• The final stage of research, comprised ethnographic
studies on 12 individuals aged between 55 and
85. This in-depth observation of older users who
had never encountered, or used a Dyson vacuum
cleaner, compared responses across a set series of
tasks or scenarios such as assembly, stair and other
cleaning, bin-emptying etc (Table 2).
• Additional areas of enquiry included listening in
on customer help-lines at Dyson during the explore
phase of the project and incorporating material and
feedback data into the develop phase.
Figure 2. Turning the vacuum cleaner on: an ethnographic
study focused on a range of key interactions or scenarios
Ethnographic vacuum cleaning scenarios: detailed observation of vacuum cleaner use among older
people aged between 55 and 85
Scenario 1
Presenting the interviewee with the product and asking them
for feedback on the assembly process
Scenario 2
Cleaning the kitchen
Scenario 3
Cleaning the stairs
Scenario 4
Emptying the bin
Table 2. Tasks observed during ethnographic vacuum-cleaning scenarios
These scenarios required the user to perform nearly
all of the tasks needed to operate the product effectively.
Analysis, along with the findings of the other
strands of research mapped the cleaning scenarios
against emerging ‘critical areas’ of interaction with
the product.
The detailed identification of the critical areas of
interaction with the vacuum cleaner were developed
into a framework for use in the early stages of the
design process and a series of recommendations
made for the development of inclusive vacuum
cleaners in the future.
AREA SCENARIO 1:
Accessing, assembling, turning on /off dismantling, putting away
Colour
Discordant
Changing colours
Meanings of colours
Black & White
Patterns
Metaphors/Symbols/Semiotics
Understanding
Ease of seeing
Diagram v text
Tactile aspects
Texture
Sensation
Force Required
Sound
Can it be used as a medium?
Would users be able to understand a warning noise?
Reference Points/commonality of features
Where do I instinctively go?
What do I want to grab?
Form
What does the form tell me?
Scale/shape/action of buttons/
catches .... / What do they want you to do?
Figure 2. Turning the vacuum cleaner on: an ethnographic study focused on a range of key interactions or scenarios
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Sensory Devices | Bryn Griffiths
Results and design outcomes
The four main streams of initial research produced
findings which were grouped into six main areas of
consideration for the improvement of interaction
between older users and the product; Form, colour,
orientation, consistency and commonality of features,
signage and sensory reassurance (see Table 3).
A further step used these ‘critical areas’ to generate
guidelines and recommendations for use in the
early stages of the design process for new product
development in the vacuum cleaner sector and
beyond.
On/off button with contrast
Juxtaposition of two components to provide good contrast
between symbol and button
Use of colour within a thermo sensitive polymer to reveal a thermal cut-out
Table 3. Design ideas
In addition to generating detailed Dyson-specific
observations, the research produced general conclusions
about the diffuculties relating to shape, colour
and communication in products used by older users.
Form
The ethnographic research revealed that the complex
form of the vacuum cleaner – termed ‘complicated’
or ‘busy’ by users – made it difficult to understand
and use. Along with such overall perceptions and
attitudes, the research gave specific insights into the
form of vacuum cleaners such as buttons that do not
reveal the motion required to operate them. Most
found it extremely difficult to stand on one leg in
order to activate the brush tool bar mechanism. Each
informant felt that more hands were required to
separate the components for use. The symbol for on/
off has little contrast between symbol and the shiny
surface of the button: glare interferes with clarity.
Colour
Colour should be viewed as a tool to assist the user in
the navigation of the product and not solely to make
the product look appealing. There are many ways
to interpret an object but in general the number of
misleading elements can be kept to a minimum, for
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Sensory Devices | Bryn Griffiths
Figure 4. During interviews the users were asked to remove
the cylinder from the machine. Having located the button they
applied force apparently indicated by the surface shape and
dismissed it upon lack of reaction.
example: users believed the yellow components on the
product to be dynamic, expecting four stationary yellow
blades on the bin interior to rotate. Buttons with
shiny surfaces create light-scatter within the eye; increased
sensitivity to glare and recovery from this glare
takes longer for older users, making shiny buttons
extremely difficult to see. Older users need contrast
between the symbols on the buttons and the colour of
the buttons themselves. The size of any symbol should
be relative to the distance at which it is viewed.
Figure 5. The introduction of another colour on a button
provides contrast that may help users with reduced vision
Orientation
The orientation of buttons and features is extremely
important if the product is to send out a clear coherent
message. For older users, it is better to have features
or buttons that the hand can operate since our
hands are generally more capable of movement than
feet. By careful positioning, the designer can create
an intuitive process for the user: buttons located so
that only the correct button can be seen – activation
reveals the second button when the previous operation
had been successfully carried out. This example
can be described as ‘layering’.
Figure 6. Many users were confused by the sequence of actions
required to operate these buttons
Figure 7. Here there is only one correct choice; a second
switch underneath could become apparent on operation
of the first
Consistency and commonality of features
As manufacturers brings out new products, it is
important that there is consistency between each
new model. The ability for older users to break
previous habits is hard to overcome and may persist
in interfering with the development of new skills.
People with memory restrictions in particular rely
on familiar and consistent controls, symbols and
procedures.
Signage
This complex area has no set standards. The designer
should not design a feature and assume that the
graphics will explain how it should be operated.
Thought and attention should be paid to the
component at a much earlier stage so that the
shape, colour etc. can be used to assist the user
in its operation.
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Sensory Devices | Bryn Griffiths
Reassurance through other senses
Most domestic appliances rely heavily on the user’s
sense of sight, causing real problems for those with
visual impairment. Domestic goods must engage
other senses, in particular touch and hearing; for elderly
users it can mean the difference between being
able to use the product and not use it and impacts on
their capacity for independent living.
Reassurance through sound
The research showed that sounds could comfort users.
Many find it satisfying to hear the dirt hitting the
hose as it is drawn into the cleaner. There are many
ways in which sound can be used to inform the user
of a problem or to alert them that they should perform
a service task. For example, the filter, as it becomes
blocked reduces the suction of the cleaner. The
use of reducing: sensors might trigger various audible
prompts to indicate that the filter needs changing or
cleaning. The same effect may be achieved by diverting
air through reeds or beads etc. to produce sound.
Reassurance through touch
Tactile sensitivity reduces with age, especially at frequencies
of 250Hz and above. Interviewees used their
sense of touch to confirm that they had performed
tasks; feeling clicks, vibrations and the resistance of
different vacuum heads in use. Many products lack
textural contrast. The use of rubber in conjunction
with polycarbonates may be all that is required to
deliver textural contrast sufficient for an elderly user
with reduced vision.
Figure 8. Findings were expressed as a framework to guide the design of vacuum cleaners in the future
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Sensory Devices | Bryn Griffiths
Inclusive Design Framework
The findings from the tasks in Stage 3 (Develop) have
been used to formulate a design framework (Figure
8). It encourages designers to consider the important
aspects when designing products for an ageing population.
The framework should be used within the
early stages of the design process so that the product
does not rely solely on graphics to communicate its
features. It aims to encourage product designers,
amongst other things, to use the third dimension
and not rely solely on two-dimensional symbols.
Discussion
The stated aim of the brief was to investigate new
ways to communicate Dyson product functions to older
users. In combining a thorough assessment of all
the ways that the vacuum cleaner communicates its
characteristics and functions with examples from the
automotive sector, the study was grounded in a high
standard of physical interface. Ethnographic methods
enabled observation of the reality of interaction
with products that occurs among older users within a
structure that identified key areas of interaction and
their precise performance in use.
Central to the challenge of this project was
the ambition to enhance product communication
through formal and sensory qualities, without resorting
to descriptions and instructions unsuited to a
domestic product in daily use. In seeking to inform
Dyson Research activity at a strategic level, the full
effect of this research is embedded in the time constraints
of the product development cycle. Long lead
times mean that the results of this research will reveal
themselves over a matter of years. The methods used
clearly demonstrate that it is possible to map the performance
of everyday domestic appliances for their
inclusivity and provide clear examples and direction
for the improvement required in interface issues. As
such the project is a useful model for the potential
improvement of a wide range of domestic and other
products.
take little or no account of the needs of older users:
in particular assumptions about visual, memory and
manipulative capacity.
• User testing can readily demonstrate the difficulties
of older users in using appliances.
• Design measures to address the different sensory
world of some older users are relatively simple to
develop.
• Mapping and forming solutions to the interface
shortcomings of products can suggest an entire
framework for the future development of more
inclusive products.
Conclusions and future work
The main conclusions of this project have revealed
great scope for the improvement of the interface
between domestic appliances and older users.
• Many assumptions about the form and orientation
of vacuum cleaner and their role in its operability
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Select Bibliography
• Warren, G. Green Ideology: Construction and
Consumption In The Home
• Morley, C. Homemakers and Design Advice in the
Postwar Period
• Wengraf, T. Documenting Domestic Culture by
Ethnographic Interview
• Clifford J. and Marcus G. Ethnographic Principles
in Practice
• Spradley, J.P. The Ethnographic Interview
• Semiotics And The Philosophy Of Language – Umberto
Eco
• Bailey, R. W., Matejka, L. and Stein, P. The Sign:
Semiotics Around the World
• MacCannell, D. and MacCannell, J. F. The Time Of
The Sign: A Semiotic Interpretation of Modern
Culture
• Cobley, P. and Jansz, L. Introducing Semiotics
• Mandel, T. The Elements Of Interface Design
• The Third Age Driver, their Characteristics and
Needs – ICE Ergonomics
• ISO/IEC Guide 71 – Guide To Address The Needs Of
Older Persons With Disabilities In Standardisation
• ISO/COPOLCO - Working Group On Elderly And
People With Disabilities
• Hackos, J. T. and Redish, J. C. User And Task Analysis
for Interface Design
Acknowledgements
• Design Council – Andreas Fruchtl (research analyst)
• Age Concern Service support
• Peter Hings – RNIB
• Rolls Royce Motor Cars Ltd. – Steve Rawley (Head of
interiors)
• Autodesign – Colin Harvey
• Ford Motors – Mike Bradley (ergonomics)
• Cambridge Ergonomics – Mike Stearn
• MSX – Collin Clifton (ergonomics)
• Rebecca Pockney – Lecturer in Occupational Therapy
• Hilary Dalke – Colour Research Unit, South Bank
University
• London Taxis – Collin Smith
• Hawthall Whiting – Russel Murphy
Thanks also to members of staff at the Helen Hamlyn
Research Centre, Royal College of Art.
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About the research partners
Dyson Research: Dyson, inventor and manufacturer
of the Dyson Dual Cyclone vacuum cleaner, launched
its first product – the DC01 – in 1993. Dyson cleaners
are now best sellers in the UK and they are sold
in 18 countries across the world. Dyson believes in
investing in R&D to create new technologies to make
better products.
www.dyson.com/
About the Research Associate
Bryn Griffiths: British. MA
(RCA) Industrial Design Engineering
1999; BSc (Hons)Ist
Class, Industrial Systems &
Business Management, University
of Westminster 1994.
Work experience: Rolls Royce
Motor Cars; Isis UK design consultants.
Awards: Rio Tinto Travel Awards; Engineering
and Physical Research Council Scholarship.
Contact: 07967 326869/b.griffiths@ukgateway.net.
The Helen Hamlyn Centre was set up at the Royal
College of Art in January 1999 to alert design and
business to the far-reaching implications of a rapidly
changing society. It works to advance a socially inclusive
approach to design through practical research
and projects with industry. Its Research
Associates Programme teams new RCA
graduates with industry partners.
www.hhrc.rca.ac.uk

The Helen Hamlyn
Centre
Royal College of Art
Kensington Gore
London SW7 2EU
T +44 (0)20 7590 4242
F +44 (0)20 7590 4244
hhc@rca.ac.uk
www.hhc.rca.ac.uk