Functional balance and upright posture are of the utmost importance for human, since
they are the condition for walking and also enable greater mobility and thus a higher
quality of life. Persons who suffered a stroke often have limited ability to maintain a
balance, thus the balance is given special treatment in the process of rehabilitation.
The present work deals with the use of movable floor as a haptic interface in the
system for non-obtrusive capture and assessment of postural abilities during the execution
of tasks, using a virtual reality in the system of tele-rehabilitation.
In the first part, we check the technical capabilities of haptic floor for creating disturbances
in the balance of human. We have determined the parameters of a controller
used in the management of device, and the measured properties, such as the bandwidth
of the device, and the speed of movement of the top plate. In the healthy volunteers
were included responses to displacement of ground in eight directions. On the basis of
the measured responses we made the norm, which was compared to the responses in one
subject after suffering a stroke. Differences can be characterized and used in estimating
the postural abilities.
In the second part, in order to assess the impact of movable floor in the exercise in
balance with virtual reality, we capture postural responses of healthy volunteers exposed
to combinations of the presence of haptic and visual feedback mesh. We observe muscle
activation of predominantly lower extremities using electromiograms and changes in the
angles of the joint of the hip, knees and ankles using triaxial accelerometers. We have
shown that the response at the task in the virtual reality is of no apparent dynamics,
while the haptic plates require dynamic response. When we used a combination of both,
the persons chose a different strategy, because the presence of virtual environment allows
pre-preparation.
The third part presents the developed software framework, which consists of services
and tools for the implementation of tele-rehabilitation. It allows execution of tasks and
remote monitoring, and management of the rehabilitation process and consists of three
parts. Central server with database and a web server that provides services through two
different web interfaces. A web site, dedicated to patient, allows him to log into the
system, to select tasks from the narrowed selection and the performance of a task itself,
which is performed as a game in virtual reality. The therapist can review the history of
performed tasks, prescribe tasks and monitor the implementation of task in real-time via
graphs of individual parameters and with the view into the virtual environment of the
task.
With this programming framework the system for balance training was implemented,
to which we ported an existing task. The operation of system was compared with conventional
exercise of balance and with exercise, supported by a standing frame, and it has
proven to be comparable according to previously and subsequently carried out clinical
tests of the three cooperating groups of patients in the subacute phase of stroke.
Both studies, analysis of the responses and the use of tele-rehabilitation system, are a
fine example of how to take advantage of the benefits offered to us by technology. Using
the responses, covered in a remote location while performing tasks in virtual reality, can
contribute to a successful tele-diagnostics, which can reduce the number of required resources;
this means less visits to specialized institutions and a smaller number of necessary
staff.
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