UWE Bristol Engineering showcase 2015

Sam Needham
Robotics
Project Supervisor
Sanja Dogramadzi:
Wearable Soft Robotic Device for Post-Stroke Shoulder Rehabilitation
Introduction:
Stroke occurs approximately 152,000 times a
year in the UK, with 1.2 million survivors; and 17
million times a year worldwide (Stroke Association,
2015). The rehabilitation process can be helped
with mechanical aid.
The aim of this project is to develop a system
that will aid in post-stroke shoulder rehabilitation.
The system will move in a forward extension to
give the user an appropriate use to grasp objects,
it will also lower the arm back to resting state. This
is a way to move the arm to rehabilitate the user.
Process:
The process involved research into similar
systems. Once an understanding of the
components needed was achieved, research into
the best components was undertaken.
The system reads sensory information from flex
sensors, picture below. Two flex sensors are used,
one to lift the arm up and one to lower the arm.
Project summary
A system has been designed and built to aid
in the post-stroke rehabilitation process for
the shoulder. The system can be used along
with regular rehabilitation and offers more
independence for the user.
Project Objectives
To design and build a system that can be
worn comfortably by the user, and to raise
and lower the arm to aid in the rehabilitation
process.
With current systems that this is based on, the
price is approximately £1200. This system has
been built with approximately £50.
Specification:
The system complies to these specifications:
1. It should be client to improve safety. Rigid
components are avoided.
2. It must be adaptable to anatomical variations
and misalignments.
3. Easy to don and doff.
4. It must be light as possible.
5. It should generate forces to assist during the
rehabilitation process.
6. It should be a cost effective system.
The shoulder and wrist support have already
been medically tried and tested making it a
suitable addition to the system. It has nor rigid
components, adaptable to anatomical variations,
easy to don and doff, very light and ‘breathable’.
They only need to be compressed a small
amount to spin the motor, as the user may not
have full control of the fingers. The motor has a
torque of 1Nm which was calculated to be suitable
to lift a 5.6kg arm.
Only one motor is used, it is combined with a H-
bridge chip to allow the motor to spin bidirectionally,
the up and down movements. In
other systems flexible Bowden cables were used,
which are similar to the cables used for bicycle
brakes, they can be very expensive. In this system
a cheaper and more feasible solution was to use
fishing line, the type that can lift a maximum of
15.6kg, which will have no problem lifting the
5.6kg arm!
The system was built and programmed using the
Arduino Uno development board, pictured below.
Normally used for prototyping which was perfect
for this system.
.
Project Conclusion
The system was built and tested. Possible
future applications of the system were also
thought of to help aid rehabilitation, such as
the leg for example.
A pulley was attached to the shaft of the motor
allowing the fishing line to coil round and thus
raise the arm.