Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

Artificial hand able to respond sensitively thanks to muscles made from smart metal wires

24.03.2015

Engineers at Saarland University have taken a leaf out of nature’s book by equipping an artificial hand with muscles made from shape-memory wire. The new technology enables the fabrication of flexible and lightweight robot hands for industrial applications and novel prosthetic devices. The muscle fibres are composed of bundles of ultrafine nickel-titanium alloy wires that are able to tense and flex. The material itself has sensory properties allowing the artificial hand to perform extremely precise movements. The research group led by Professor Stefan Seelecke will be showcasing their prototype artificial hand and how it makes use of shape-memory ‘metal muscles’ at HANNOVER MESSE.

HANNOVER MESSE 2015 – the world’s largest industrial fair – from April 13th to April 17th. The team, who will be exhibiting at the Saarland Research and Innovation Stand in Hall 2, Stand B 46, are looking for development partners.


Filomena Simone, an engineer in the research team led by Professor Stefan Seelecke, is working on the prototype of the artificial hand.

Credit: Oliver Dietze

The hand is the perfect tool. Developed over millions of years, its ‘design’ can certainly be said to be mature. The hand is extraordinarily mobile and adaptable, and the consummate interaction between the muscles, ligaments, tendons, bones and nerves has long driven a desire to create a flexible tool based upon it.

The research team led by Professor Stefan Seelecke from Saarland University and the Center for Mechatronics and Automation Technology (ZeMA) is using a new technology based on the shape memory properties of nickel-titanium alloy. The engineers have provided the artificial hand with muscles that are made up from very fine wires whose diameter is similar to that of a human hair and that can contract and relax.

‘Shape-memory alloy (SMA) wires offer significant advantages over other techniques,’ says Stefan Seelecke. Up until now, artificial hands, such as those used in industrial production lines, have relied on a lot of complex background technology. As a result they are dependent on other devices and equipment, such as electric motors or pneumatics, they tend to be heavy, relatively inflexible, at times loud, and also expensive.

‘In contrast, tools fabricated with artificial muscles from SMA wire can do without additional equipment, making them light, flexible and highly adaptable. They operate silently and are relatively cheap to produce. And these wires have the highest energy density of all known drive mechanisms, which enables them to perform powerful movements in restricted spaces,’ explains Seelecke. The term ‘shape memory’ refers to the fact that the wire is able to ‘remember’ its shape and to return to that original predetermined shape after it has been deformed.

‘This property of nickel-titanium alloy is a result of phase changes that occur within the material. If the wire becomes warm, which happens, for instance, when it conducts electricity, the material transforms its lattice structure causing it to contract like a muscle,’ says Seelecke.

The engineers use ‘smart’ wires to play the role of muscles in the artificial hand. Multiple strands of shape-memory wire connect the finger joints and act as flexor muscles on the front-side of the finger and as extensor muscles on the rear. In order to facilitate rapid movements, the engineers copied the structure of natural human muscles by grouping the very fine wires into bundles to mimic muscle fibres.

These bundles of wires are as fine as a thread of cotton, but have the tensile strength of a thick wire. ‘The bundle can rapidly contract and relax while exerting a high tensile force,’ explains Filomena Simone, an engineer who is working on the prototype of the artificial hand as part of her doctoral research.

‘The reason for this behaviour is the rapid cooling that is possible because lots of individual wires present a greater surface area through which heat can be dissipated. Unlike a single thick wire, a bundle of very fine wires can undergo rapid contractions and extensions equivalent to those observed in human muscles. As a result, we are able to achieve fast and smooth finger movements,’ she explains.

Another effect of using the shape-memory metal wires is that the hand can respond in a natural manner when someone intervenes while a particular movement is being carried out. This means that humans can literally work hand-in-hand with the prototype device. A semiconductor chip controls the relative motions of the SMA wires allowing precise movements to be carried out.

And the system does not need sensors. ‘The material from which wires are made has sensor properties. The controller unit is able to interpret electric resistance measurement data so that it knows the exact position of the wires at any one time,’ says Seelecke. This enables the hand and the fingers to be moved with high precision.

The research team will be exhibiting their system prototypes at HANNOVER MESSE 2015 and showcasing the potential of the technology by performing hand grasps and the controlled movement of individual fingers. The researchers want to continue developing the prototype and improve the way in which it simulates the human hand. This will involve modelling hand movement patterns and exploiting the sensor properties of SMA wire.


Contact:
Professor Stefan Seelecke (Multifunctional Materials and Systems Lab),
Tel. +49 (0)681 302-71341; E-mail: stefan.seelecke@mmsl.uni-saarland.de
http://www.mmsl.uni-saarland.de/
Benedikt Holz, Tel.: +49 (0)681 302-71345, E-mail: benedikt.holz@mmsl.uni-saarland.de
Filomena Simone, Tel.: +49 (0)681 302-71347 E-mail: filomena.simone@mmsl.uni-saarland.de

During HANNOVER MESSE 2015, the Saarland Research and Innovation Stand can be contacted at Tel.: +49 (0)681 302-68500

Note for radio journalists: Studio-quality telephone interviews can be conducted using broadcast audio IP codec technology (IP direct dial or via the ARD node 106813020001). Interview requests should be addressed to the university’s Press and Public Relations Office (+49 (0)681 302-64091 or -2601).

Background:
Saarland University, Saarland University of Applied Sciences (HTW) and industrial partners are working together at ZeMA – Center for Mechatronics and Automation Technology in Saarbrücken to strengthen the fields of mechatronic engineering and industrial automation in Saarland and to promote technology transfer. ZeMA is home to a large number of industry-specific development projects and projects aimed at transforming research findings into practical industrial applications. http://www.zema.de/

Claudia Ehrlich | Universität des Saarlandes

More articles from HANNOVER MESSE:

nachricht Measurement of components in 3D under water
01.04.2015 | Fraunhofer-Institut für Angewandte Optik und Feinmechanik IOF

nachricht Greater productivity in industry thanks to digitalization
26.02.2015 | Siemens AG

All articles from HANNOVER MESSE >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Das Auto lernt vorauszudenken

Ein neues Christian Doppler Labor an der TU Wien beschäftigt sich mit der Regelung und Überwachung von Antriebssystemen – mit Unterstützung des Wissenschaftsministeriums und von AVL List.

Wer ein Auto fährt, trifft ständig Entscheidungen: Man gibt Gas, bremst und dreht am Lenkrad. Doch zusätzlich muss auch das Fahrzeug selbst ununterbrochen...

Im Focus: Vorbild Delfinhaut: Elastisches Material vermindert Reibungswiderstand bei Schiffen

Für eine elegante und ökonomische Fortbewegung im Wasser geben Delfine den Wissenschaftlern ein exzellentes Vorbild. Die flinken Säuger erzielen erstaunliche Schwimmleistungen, deren Ursachen einerseits in der Körperform und andererseits in den elastischen Eigenschaften ihrer Haut zu finden sind. Letzteres Phänomen ist bereits seit Mitte des vorigen Jahrhunderts bekannt, konnte aber bislang nicht erfolgreich auf technische Anwendungen übertragen werden. Experten des Fraunhofer IFAM und der HSVA GmbH haben nun gemeinsam mit zwei weiteren Forschungspartnern eine Oberflächenbeschichtung entwickelt, die ähnlich wie die Delfinhaut den Strömungswiderstand im Wasser messbar verringert.

Delfine haben eine glatte Haut mit einer darunter liegenden dicken, nachgiebigen Speckschicht. Diese speziellen Hauteigenschaften führen zu einer signifikanten...

Im Focus: Kaltes Wasser: Und es bewegt sich doch!

Bei minus 150 Grad Celsius flüssiges Wasser beobachten, das beherrschen Chemiker der Universität Innsbruck. Nun haben sie gemeinsam mit Forschern in Schweden und Deutschland experimentell nachgewiesen, dass zwei unterschiedliche Formen von Wasser existieren, die sich in Struktur und Dichte stark unterscheiden.

Die Wissenschaft sucht seit langem nach dem Grund, warum ausgerechnet Wasser das Molekül des Lebens ist. Mit ausgefeilten Techniken gelingt es Forschern am...

Im Focus: Hyperspektrale Bildgebung zur 100%-Inspektion von Oberflächen und Schichten

„Mehr sehen, als das Auge erlaubt“, das ist ein Anspruch, dem die Hyperspektrale Bildgebung (HSI) gerecht wird. Die neue Kameratechnologie ermöglicht, Licht nicht nur ortsaufgelöst, sondern simultan auch spektral aufgelöst aufzuzeichnen. Das bedeutet, dass zur Informationsgewinnung nicht nur herkömmlich drei spektrale Bänder (RGB), sondern bis zu eintausend genutzt werden.

Das Fraunhofer IWS Dresden entwickelt eine integrierte HSI-Lösung, die das Potenzial der HSI-Technologie in zuverlässige Hard- und Software überführt und für...

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics
Veranstaltungen

Internationale Fachkonferenz IEEE ICDCM - Lokale Gleichstromnetze bereichern die Energieversorgung

27.06.2017 | Veranstaltungen

Internationale Konferenz zu aktuellen Fragen der Stammzellforschung

27.06.2017 | Veranstaltungen

Fraunhofer FKIE ist Gastgeber für internationale Experten Digitaler Mensch-Modelle

27.06.2017 | Veranstaltungen

 
VideoLinks
B2B-VideoLinks
Weitere VideoLinks >>>
Aktuelle Beiträge

Umfangreiche Fördermaßnahmen für Forschung an Chromatin, Nebenniere und Krebstherapie

28.06.2017 | Förderungen Preise

Immunabwehr: Wie Proteine Membranbläschen zusammenbringen

28.06.2017 | Biowissenschaften Chemie

Das Auto lernt vorauszudenken

28.06.2017 | Maschinenbau