Rehabilitation Technology;. The applicability of Smart materials. Arjan Buis, PhD. .... Translation into Rehabilitation Technology. Prosthetics. &. Orthotics ...
Dr. Arjan Buis
BIOMEDICAL ENGINEERING Technology for Life
Rehabilitation Technology; The applicability of Smart materials Arjan Buis, PhD. Biomedical engineering, University of Strathclyde, Glasgow, Scotland, UK
Overview o Biomedical engineering at Strathclyde o Introduction to Smart materials.
o Transducers, Sensors & Actuators. o Translation into Rehabilitation technology.
Biomedical Engineering
Activity Scope (research)
Rehabilitation Engineering
Introduction to Smart materials o What do we mean by “Smart”
o Definition of Smart Material behaviour. Material that has the intrinsic or extrinsic capabilities to respond to an external stimulus in a functionally useful, reliable, reproducible and usually reversible manner. Smart behaviour is the reaction of a material to stimuli from its environment, no material can be Smart in isolation, it must be a part of a structure or system such as your mobile phone, the coffee mug or a leg prosthesis.
Types of Smart materials o o o o o o o
Chromogenic. Halo-chromic . Shape Memory; Alloys , Polymers. Piezoelectric. Magneto-strictive. Smart fluids. Smart Fabrics.
Chromogenic Materials o Chromogenic materials change colour in response to external stimuli: o Electrical
o Optical (i.e. light intensity) o Thermal changes.
www.slowtwitch.com images5DON186U thermochromic-urinal_zTLKJ_58
Halochromic materials; o Colour change as a result of changing acidity
imagesLDT0P9XX
Shape Memory materials; Alloys Nitinol (Ni-Ti) One-way SME Two-way SME Pseudo-elasticity
Polymers
Ag-Cd 44/49 at.% Cd Au-Cd 46.5/50 at.% Cd Cu-Al-Ni 14/14.5 wt.% Al and 3/4.5 wt.% Ni Cu-Sn approx. 15 at.% Sn Cu-Zn 38.5/41.5 wt.% Zn Cu-Zn-X (X = Si, Al, Sn) Fe-Pt approx. 25 at.% Pt Mn-Cu 5/35 at.% Cu Fe-Mn-Si Pt alloys Co-Ni-Al Co-Ni-Ga Ni-Fe-Ga Ti-Pd in various concentrations Ni-Ti (~55% Ni) Ni-Ti-Nb Ni-Mn-Ga
o Stimuli responsive polymers (plastics) Applications; drug delivery, textiles, artificial muscles etc. Jani, J. M.; Leary, M.; Subic, A.; Gibson, M. A. (2013). "A Review of Shape Memory Alloy Research, Applications and Opportunities". Materials & Design.
Piezoelectric materials; o Produces a voltage when stress is applied
www.youtube.com/watch?v=OPwIKWSiwVU www.youtube.com/watch?v=RydSojhrur8
Magnetostrictive materials o Magnetostrictive materials can convert magnetic energy into kinetic energy, or the reverse, and are used to build actuators and sensors.
Magnetostriction_by_Zureks
Smart fluids o A smart fluid is a fluid whose properties (for example the viscosity) can be changed by applying an magnetic field or a electric field .
www.youtube.com/watch?v=7LArS6tlVNg www.youtube.com/watch?v=yViGgApwrIk
Transducers, Sensors and Actuators Sensor(s) oA sensor is a device, which responds to an input quantity by generating signals proportional to the changing measurand, usually in the form of an electrical or optical signal. Transducer(s) oA transducer is a device that converts energy from one form to another. When a transducer converts a measurable quantity (sound pressure level, optical intensity, magnetic field, etc) to an electrical voltage or an electrical current we call it a sensor. Actuator(s) oWhen the transducer converts an electrical signal into another form of energy, such as sound, mechanical movement, it is called an Actuator. cas.ee.ic.ac.uk
Transducers, Sensors and Actuators
www.pi.com linear actuator www3.gehealthcare.com
Transducers, Sensors and Actuators
www.pi.com linear actuator www3.gehealthcare.com
Translation into Rehabilitation Technology
Prosthetics & Orthotics
Prosthetic examples
Orthotic examples
Prosthetics
Prosthetics
Prosthetics & Smart materials Prosthetic components
Otto Bock healthcare gmbh Ossur ltd
Prosthetics Body/device interface; What can smart materials contribute? o Issues: Quantification of socket fit.
Interface pressure and shear Bone movement Activity Temperature Blood flow Volume management
Prosthetics Interface pressure and shear
Boundary shear
Pressure
Shear stress level
Pressure level
Prosthetics Bone movement
Lateral
Lateral
A
P
Medial
Hydro Cast
P
A
Medial
Ischial Containment
Prosthetics o Activity
o Temperature o Blood flow
o Volume management
Future developments Sensor(s)
o Toward ubiquitous mobility solutions for body sensor networks on Healthcare. o Dynamic adaptable prosthetic sockets. o Dynamic adaptable orthotics. o Powered prosthesis/orthosis using artificial muscle concepts. o Self healing components.
Thank you!