PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

A micro-muscular breakthrough

Berkeley Lab researchers make a powerful new microscale torsional muscle/motor from vanadium dioxide

2013-12-20
(Press-News.org) Contact information: Lynn Yarris
lcyarris@lbl.gov
510-486-5375
DOE/Lawrence Berkeley National Laboratory
A micro-muscular breakthrough Berkeley Lab researchers make a powerful new microscale torsional muscle/motor from vanadium dioxide

Vanadium dioxide is poised to join the pantheon of superstars in the materials world. Already prized for its extraordinary ability to change size, shape and physical identity, vanadium dioxide can now add muscle power to its attributes. A team of researchers with the U.S. Department of Energy (DOE)'s Lawrence Berkeley National Laboratory (Berkeley Lab) has demonstrated a micro-sized robotic torsional muscle/motor made from vanadium dioxide that for its size is a thousand times more powerful than a human muscle, able to catapult objects 50 times heavier than itself over a distance five times its length within 60 milliseconds – faster than the blink of an eye.

"We've created a micro-bimorph dual coil that functions as a powerful torsional muscle, driven thermally or electro-thermally by the phase transition of vanadium dioxide," says the leader of this work, Junqiao Wu, a physicist who holds joint appointments with Berkeley Lab's Materials Sciences Division and the University of California-Berkeley's Department of Materials Science and Engineering. "Using a simple design and inorganic materials, we achieve superior performance in power density and speed over the motors and actuators now used in integrated micro-systems."

Wu is the corresponding author of a paper describing this research in the journal Advanced Materials. The paper is titled "Powerful, Multifunctional Torsional Micro Muscles Activated by Phase Transition." Co-authors are Kai Liu, Chun Cheng, Joonki Suh, Robert Tang-Kong, Deyi Fu, Sangwook Lee, Jian Zhou and Leon Chua.

What makes vanadium dioxide highly coveted by the electronics industry is that it is one of the few known materials that's an insulator at low temperatures but abruptly becomes a conductor at 67 degrees Celsius. This temperature-driven phase transition from insulator-to-metal is expected to one day yield faster, more energy efficient electronic and optical devices. However, vanadium dioxide crystals also undergo a temperature-driven structural phase transition whereby when warmed they rapidly contract along one dimension while expanding along the other two. This makes vanadium dioxide an ideal candidate material for creating miniaturized, multi-functional motors and artificial muscles.

"Miniaturizing rotary motors is important for integrated micro-systems and has been intensively pursued over the past decades," Wu says. "The power density of our micro-muscle in combination with its multi-functionality distinguishes it from all current macro- or micro-torsional actuators/motors."

Wu and his colleagues fabricated their micro-muscle on a silicon substrate from a long "V-shaped" bimorph ribbon comprised of chromium and vanadium dioxide. When the V-shaped ribbon is released from the substrate it forms a helix consisting of a dual coil that is connected at either end to chromium electrode pads. Heating the dual coil actuates it, turning it into either a micro-catapult, in which an object held in the coil is hurled when the coil is actuated, or a proximity sensor, in which the remote sensing of an object (meaning without touching it) causes a "micro-explosion," a rapid change in the micro-muscle's resistance and shape that pushes the object away.

"Multiple micro-muscles can be assembled into a micro-robotic system that simulates an active neuromuscular system," Wu says. "The naturally combined functions of proximity sensing and torsional motion allow the device to remotely detect a target and respond by reconfiguring itself to a different shape. This simulates living bodies where neurons sense and deliver stimuli to the muscles and the muscles provide motion."

The vanadium dioxide micro-muscles demonstrated reversible torsional motion over one million cycles with no degradation. They also showed a rotational speed of up to approximately 200,000 rpm, amplitude of 500 to 2,000 degrees per millimeters in length, and an energy power density up to approximately 39 kilowatts/kilogram.

"These metrics are all orders of magnitudes higher than existing torsional motors based on electrostatics, magnetics, carbon nanotubes or piezoelectrics," Wu says.

The heating of the vanadium dioxide micro-muscle to actuate it can be done either globally with a tiny heating pad, or with an electrical current applied to the dual coil. Wu says heating with the electric current is the better way to go because it allows for the selective heating of individual micro-muscles and the heating and cooling process is much faster. In addition, as vanadium dioxide absorbs light and coverts it into heat, the coil can also be triggered optothermally. "With its combination of power and multi-functionality, our micro-muscle shows great potential for applications that require a high level of functionality integration in a small space," Wu says.



INFORMATION:

This work was supported by a DOE Office of Science Early Career Award to the University of California, Berkeley.

Lawrence Berkeley National Laboratory addresses the world's most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab's scientific expertise has been recognized with 13 Nobel prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy's Office of Science. For more, visit http://www.lbl.gov.

The DOE Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.



ELSE PRESS RELEASES FROM THIS DATE:

Inside the Bloomberg public health toolbox

2013-12-20
Inside the Bloomberg public health toolbox Health policy insiders reveal details of the data-driven process behind the city's public health successes; approach can be a model for other cities nationwide December 19, 2013 —As Mayor ...

Women's perceptions of 'normal' female genitalia may be influenced by exposure to modified images

2013-12-20
Women's perceptions of 'normal' female genitalia may be influenced by exposure to modified images Women's perceptions of what is considered normal and desirable female genitalia may be influenced by exposure to modified images, suggests a new study published today (20 December) ...

First plant-based 'microswimmers' could propel drugs to the right location

2013-12-19
First plant-based 'microswimmers' could propel drugs to the right location In the quest to shrink motors so they can maneuver in tiny spaces like inside and between human cells, scientists have taken inspiration from millions of years of plant evolution and ...

UCLA researcher highlights advances in nanotechnology's fight against cancer

2013-12-19
UCLA researcher highlights advances in nanotechnology's fight against cancer As cancer maintains its standing as the second leading cause of death in the U.S., researchers have continued their quest for safer and more effective treatments. ...

Ways of the photoelectric effect; How physicists have learned how to select them

2013-12-19
Ways of the photoelectric effect; How physicists have learned how to select them This work was recently published in Physical Review Letters. In contrast to its apparent simplicity (that brought Einstein his Nobel Prize), the photoelectric effect, when an ...

NOAA: Coastal ocean aquaculture can be environmentally sustainable

2013-12-19
NOAA: Coastal ocean aquaculture can be environmentally sustainable Little to no effects on coastal ocean environment seen with proper safeguards, planning Specific types of fish farming can be accomplished with minimal or no harm to the coastal ocean environment as long ...

Physical inactivity after cardiac surgery linked with substantially higher risk of depression

2013-12-19
Physical inactivity after cardiac surgery linked with substantially higher risk of depression Patients undergoing cardiac surgery should be assessed for depression and physical activity, say researchers in the Canadian Journal of Cardiology Philadelphia, PA, December ...

Survey reveals regulatory agencies viewed as unprepared for nanotechnology

2013-12-19
Survey reveals regulatory agencies viewed as unprepared for nanotechnology Three stakeholder groups agree that regulators are not adequately prepared to manage the risks posed by nanotechnology, according to a paper published in the peer-reviewed ...

New data compression method reduces big-data bottleneck; outperforms, enhances JPEG

2013-12-19
New data compression method reduces big-data bottleneck; outperforms, enhances JPEG New discovery is rooted in physics and the arts In creating an entirely new way to compress data, a team of researchers from the UCLA Henry Samueli School of Engineering ...

Data are lost to science at 'astonishing rate'

2013-12-19
Data are lost to science at 'astonishing rate' New evidence reported in the Cell Press journal Current Biology on December 19 confirms long-held fears about the fate of scientific data. Careful evaluation of more than 500 randomly selected studies found that the original data ...

LAST 30 PRESS RELEASES:

Exercise as an anti-ageing intervention to avoid detrimental impact of mental fatigue

UMass Amherst Nursing Professor Emerita honored as ‘Living Legend’

New guidelines aim to improve cystic fibrosis screening

Picky eaters by day, buffet by night: Butterfly, moth diets sync to plant aromas

Pennington Biomedical’s Dr. Leanne Redman honored with the E. V. McCollum Award from the American Society for Nutrition

CCNY physicists uncover electronic interactions mediated via spin waves

Researchers’ 3D-printing formula may transform future of foam

Nurture more important than nature for robotic hand

Drug-delivering aptamers target leukemia stem cells for one-two knockout punch

New study finds that over 95% of sponsored influencer posts on Twitter were not disclosed

New sea grant report helps great lakes fish farmers navigate aquaculture regulations

Strain “trick” improves perovskite solar cells’ efficiency

How GPS helps older drivers stay on the roads

Estrogen and progesterone stimulate the body to make opioids

Dancing with the cells – how acoustically levitating a diamond led to a breakthrough in biotech automation

Machine learning helps construct an evolutionary timeline of bacteria

Cellular regulator of mRNA vaccine revealed... offering new therapeutic options

Animal behavioral diversity at risk in the face of declining biodiversity

Finding their way: GPS ignites independence in older adult drivers

Antibiotic resistance among key bacterial species plateaus over time

‘Some insects are declining but what’s happening to the other 99%?’

Powerful new software platform could reshape biomedical research by making data analysis more accessible

Revealing capillaries and cells in living organs with ultrasound

American College of Physicians awards $260,000 in grants to address equity challenges in obesity care

Researchers from MARE ULisboa discover that the European catfish, an invasive species in Portugal, has a prolonged breeding season, enhancing its invasive potential

Rakesh K. Jain, PhD, FAACR, honored with the 2025 AACR Award for Lifetime Achievement in Cancer Research

Solar cells made of moon dust could power future space exploration

Deporting immigrants may further shrink the health care workforce

Border region emergency medical services in migrant emergency care

Resident physician intentions regarding unionization

[Press-News.org] A micro-muscular breakthrough
Berkeley Lab researchers make a powerful new microscale torsional muscle/motor from vanadium dioxide