A
ccording to the National Stroke
Association (http://www.stroke.org),
in the US alone, there are more
than 750,000 people experiencing
a new or recurrent stroke each year, leading to
motor disabilities. There is considerable evidence
which directly links functional recovery from a
stroke to the duration, frequency, regularity, and
intensity of physical (motion and force) interac-
tions in a rehabilitation regimen.
1,2
To this end, we wanted to develop the archi-
tecture and algorithms for an inexpensive haptic
telerehabilitation framework that extends the
individualized interactive nature of traditional
rehabilitation therapies to patients’ homes. We
implemented this in the form of the haptic
Virtual Driving Environment (hVDE), with an
intended audience of patients with upper limb
(UL) dysfunction (secondary to a cerebrovascular
event, such as a stroke or physical injury). For a
brief background on important considerations as
well as the state of work in the field, see the side-
bar, “Home-Based Rehabilitation Programs.”
Architecture
The hVDE, shown in Figure 1 (on page 34),
serves as an illustrative example of an individual-
ized interactive haptic telerehabilitation frame-
work by allowing us to integrate multiple aspects
of our research. At the same time, it lets us identi-
fy the issues with development, implementation,
and deployment of a flexible, reconfigurable,
inexpensive, portable telerehabilitation tool, suit-
able for setup in patients’ homes and outpatient
clinics. Finally, the development of such a reha-
bilitation tool in the context of driving, one of
the higher activities of daily living, can serve to
enhance the motivation and compliance aspects
of a therapeutic regimen. However, we note that
this hVDE is intended to serve as a network-based
tool for assessment and rehabilitation of UL
physical motor dysfunction and not as a driving
simulator for cognitive assessment. (See for com-
parison Systems Technology’s STISIM Drive sim-
ulator at http://www.systemstech.com/index.
php?pid=22.)
Patient interface
The hVDE consists of a patient interface (ulti-
mately intended to be home based) and a thera-
pist interface (ultimately intended to be at a
remote central hospital location) that are con-
nected through the Internet. The patient interface
serves both as the data-acquisition framework as
well as the exercise-deployment framework. It
consists of force-feedback kinesthetic-interface
devices coupled with a variety of exercise scenar-
ios implemented in the form of immersive dri-
ving activities within a haptics-enabled virtual
environment.
Kinesthetic interface devices
A careful selection of the kinesthetic interface
is important because it serves to stimulate the
sense of touch and movement, while creating
quantitatively measurable and customizable pat-
terns of user motions and forces. We focused on
selecting and validating the use of low-cost,
mass-produced devices (such as the Microsoft
Sidewinder force-feedback steering wheel and
hobby-rate gyros) with simplified PC interfaces
(Universal Serial Bus-based versus explicit data
acquisition). Additionally, such commercial, off-
the-shelf gaming devices employ standard soft-
ware interfaces making them easy to control
from a PC environment. For example, we took
advantage of the extensive DirectX libraries of
force-feedback (FFB) effects (available free at
http://www.microsoft.com/windows/directx/
default.aspx). These can be composed, within our
specially developed Matlab/DirectX FFB interface
32 1070-986X/06/$20.00 © 2006 IEEE Published by the IEEE Computer Society
Individualized
Interactive
Home-Based
Haptic
Telerehabilitation
Chetan Jadhav, Pravin Nair,
and Venkat Krovi
State University of New York at Buffalo
Haptic User Interfaces for Multimedia Systems
We present a haptic
telerehabilitation
framework for
patients with upper-
limb dysfunction
that is well-suited for
deployment in
patients’ homes.
Specifically, a
commercial-off-the-
shelf (COTS) haptic
force-feedback
driving wheel
interfaces with a PC
to create a haptic
Virtual Driving
Environment
(hVDE). Coupling
this framework with
parametric exercise/
movement protocols—
structured as driving
exercises along
paths of varying
complexity—is the
key to the creation
of an inexpensive,
immersive, and yet
individualized
personal-movement
trainer.