Treat Me Well: Affective and Physiological Feedback
for Wheelchair Users
Octavian Postolache
Instituto de
Telecomunicações
ISCTE-IUL,
Lisbon, Portugal
opostolache@lx.it.pt
Pedro Silva Girão,
Mário Ribeiro
Instituto de
Telecomunicações
Lisbon, Portugal
psgirao@ist.utl.pt
Helder Carvalho,
André Catarino,
Universidade do Minho,
Braga, Portugal
helder@det.uminho.pt
Gabriela Postolache
Universidade Atlântica,
Oeiras, Portugal
gabrielap@uatlantica.pt
Abstract — This work reports a electrocardiograph and skin
conductivity hardware architecture, based on E-textile
electrodes, attached to a wheelchair for affective and
physiological computing. Appropriate conditioning circuits and a
microcontroller platform that performs acquisition, primary
processing, and communication using Bluetooth were designed
and implemented. To increase the accuracy and repeatability of
the skin conductivity measuring channel, force measurement
sensors were attached to the system certifying measuring contact
force on the electrode level. Advanced processing including R-
wave peak detector, adaptive filtering and autonomic nervous
system analysis based on wavelets transform was designed and
implemented on a server. A central design of affective recognition
and biofeedback system is described.
Keywords - affective computing, physiological computing,
embedded system, E-textile, heart rate variability
I. INTRODUCTION
Mrs. Alda (fictitious name) is an old age woman with elegant
body posture and clothes. Age traces in her clear pink skin are
faded by brilliance of her blue tiny eyes remembering the
many grannies who with goodness and wisdom reflected in the
hands and body movements, gathered around the warm cakes
and fascinating stories, the grandchildren, the family, the
community. She is an 88 years old lady invited to a Nursing
Workshop to speak about her experience on retirement
residence where she has been living for the past 5 years. She
says that she feels well mainly when she can receive her
family visits and when she can talk with the nurse. When
asked to indicate what she desires to demand from any nurse
from a retirement residence, she says shortly, with a smile that
seems guilty, that what she wants is to be “well treated”.
Nobody ask her to give examples of what she means by “well
treated”, perhaps because before her presence on the
workshop, was analyzed a text from a letter of a American
nurse, Mrs. Rosemary Wills, who in order to prepare her
future in a nursing home, wrote on the needs of aged people
and on the attitude that nurses should have in order to respect
old people’s dignity. It is outlined in this letter that – “Perhaps
it will seem demanding, exaggerated in what I want, but what
I want is just to receive affection, to be well treated, and a
friendly, lovely person to take charge of me”.
Our team has been involved in the development of electronic
health systems that allow non-invasive or unobtrusive health
and healthcare monitoring. Currently, we investigate
developed or in course of implementation technologies that
should allow affective communication, a perception of well
treatment, and might turn the caregivers more friendly and
lovely.
In our work we search for solution to a range of issues related
with affective and physiological computing for wheelchair
users: What emotions or moods should be outlined, when, and
how? Are deep models of emotion necessary? The programed
software should respond to all situations or can respond only
to some events and selected requirements? How the affective
expressions maintain subject engagement? Which expressive
modalities should be used (e.g. face expressions, gestures,
behavior selection)? What role do the subject´s emotions play
in the developed affective and physiological sensing? Does the
personality of the involved people must be assessed in
affective computing? What information about the person
affective reactions should enable adaptations to the daily life
challenges?
The aim of this work is to explore the rich possibilities of
affective computing and physiological computing in order to
set out new research for future healthcare solutions. In
Sections 2 and 3 of the paper a general introduction on
affective and physiological computing is presented. In Section
4 we introduce our work on unobtrusive psychophysiological
interactive computer system implementation. Finally, we
conclude with future directions of research.
II. AFFECTIVE COMPUTING
Affective Computing is a “branch of study and development
of artificial intelligence that deals with the design of systems
and devices that can recognize, interpret, and process human
emotions” [1]. The pioneer of this type of research, Rosalind
Picard, defines Affective Computing as “computing that
relates to, arises from, or deliberately influences emotion” [2].
978-1-4673-0882-3/12/$31.00 ©2012 IEEE