In Europe, strokes are the most common cause of physical disability
among the elderly. This often result in paralysis of one side of the
body, and many patients suffer much reduced physical mobility and are
often unable to walk on their own.
These are the hard facts the EU
project CORBYS has taken seriously. Researchers in six countries are
currently developing a robotic system designed to help stroke patients
re-train their bodies. The concept is based on helping the patient by
constructing a system consisting of powered orthosis to help patient in
moving his/her legs and a mobile platform providing patient mobility.
The CORBYS researchers are also working with the cognitive aspects.
The aim is to enable the robot to interpret data from the patient and
adapt the training programme to his or her capabilities and intention.
This will bring rehabilitation robots to the next level.
Back to walking normally
It is vital to get stroke patients up on their feet as soon as possible. They must have frequent training exercises, and re-learn how to walk so that they can function as good as possible on their own.
Why a robot? “Absolutely, because it is
difficult to meet these requirements using today’s work-intensive manual
method where two therapists assisting the patient by lifting one leg
after the other”, says ICT researcher Anders Liverud at SINTEF, which is
one of the CORBYS project partners.
Robot-patient learning
CORBYS involves the use of physiological
data such as heart rate, temperature and muscle activity measurements to
provide feedback to the therapist and help control the robot. Do the
patient’s legs always go where the patient want? Is the patient getting
tired and stressed?
“The walking robot has several settings, and the therapist selects
the correct mode based on how far the patient has come in his or her
rehabilitation”, says Liverud. “The first step is to attach sensors to
the patient’s body and let them walk on a treadmill. A therapist
manually corrects the walking pattern and, with the help of the sensors,
create a model of the patient’s walking pattern”, he says.
In the next mode, the system adjusts the walking pattern to the
defined model. New adjustments are made and are used to improve
optimisation of the walking pattern.
“The patient wears an EEG cap which measures brain activity", says
Liverud. “By using these signals combined with input from other
physiological and system sensors, the robotic system registers whether
the patient wants to stop, change speed or turn, and can adapt
immediately", he says. “The robot continues to correct any walking
pattern errors. However, since it also allows the patient the freedom to
decide where and how he or she walks, the patient experiences control
and keeps motivation to continue with the training”, says Liverud.
Working with Europe
The European researchers have now completed specification of the system and its components, and construction of the robot is underway.
Construction involves a large team. The
University of Bremen is heading the project and developing the
architecture to integrate all system modules, and German wheelchair,
orthosis and robotics experts are constructing the mechanical
components, while two UK universities are working with cognitive
aspects. Spanish specialists are addressing brain activity measurements
and the University of Brussels is looking into robot control. SINTEF is
working with the sensors and the final functional integration of the
system.
In a year’s time construction will be completed and the robot
will be tested on stroke patients at rehabilitation institutes in
Slovenia and Germany. The CORBYS project has a total budget of EUR 8.7
million.
Source: SINTEF