Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

ASU, Walter Reed researchers create prosthesis of the future

03.05.2007
Researchers at Arizona State University's Polytechnic campus and the Military Amputee Research Program at Walter Reed Army Medical Center are teaming up to create the next generation of powered prosthetic devices based on lightweight energy storing springs.

The device, nicknamed SPARKy, short for Spring Ankle with Regenerative Kinetics, will be a first-of-its-kind smart, active and energy-storing transtibial (below-the-knee) prosthesis.

Existing technology in prosthetic devices is largely passive and requires the amputee to use 20 to 30 percent more energy to propel themselves forward when walking compared to an able-bodied person, according to Thomas Sugar, ASU assistant professor of engineering at the Polytechnic campus.

Once complete, SPARKy is expected to provide functionality with enhanced ankle motion and push-off power comparable to the gait of an able-bodied individual.

"A gait cycle describes the natural motion of walking starting with the heel strike of one foot and ending with the heel strike of the same foot," says Sugar. "The cycle can be split into two phases — stance and swing. We are concerned with storing energy and releasing energy (regenerative kinetics) in the stance phase."

When you look at the mechanics of walking, it can be described as catching a series of falls, explains Sugar. In the team's device, a tuned spring brakes falls and stores energy as the leg rolls over the ankle during the stance phase, similar to the Achilles tendon.

Sugar's team, made up of doctoral students Joseph Hitt and Matthew Holgate, and ASU Barrett Honors College student Ryan Bellman, have coined SPARKy a robotic tendon because of its bionic properties.

"What we hope to create is a robotic tendon that actively stretches springs when the ankle rolls over the foot, thus allowing the springs to thrust or propel the artificial foot forward for the next step," said Sugar. "Because energy is stored, a lightweight motor can be used to adjust the position of a uniquely tuned spring that provides most of the power required for gait. Thus, less energy is required from the individual."

The team is the first to apply regenerative kinetics to design a lightweight prosthetic device. Others are using large motors combined with harmonic drives, a monopropellant or extremely high-pressure oil.

Sugar's team already has proof that SPARKy is working. In recent experiments with able-bodied subjects outfitted with a robotic ankle orthosis, or a powered assist device, the researchers found that the spring and motor combination was able to amplify the motor power by three-fold. This significant finding allows SPARKy to be downsized from a 6 to 7 kg motor system to a 1 kg (2 lb) system, which is significant weight savings for those who wear a prosthetic.

"We expect this device to revolutionize prosthetics and will be especially helpful for military personnel wounded in active duty," says Hitt.

The project is a multi-phased effort led by ASU's Human Machine Integration Lab, Arise Prosthetics, Phoenix, and Robotics Group Inc., Scottsdale, Ariz. Arise Prosthetics is helping in the fitting of the device and Robotics Group, Inc. is designing embedded processors and motor amplifiers.

The first phase of SPARKy featuring the robotic tendon is expected to be ready for demonstration in December 2007. "I will know it is successful when a wounded solider is able to walk using the device on a treadmill," said Sugar about this phase.

The project will culminate with the functionality to support walking in a daily environment, which is expected in 2009.

Christine Lambrakis | EurekAlert!
Further information:
http://www.asu.edu

More articles from Health and Medicine:

nachricht 'Icebreaker' protein opens genome for t cell development, Penn researchers find
21.02.2018 | University of Pennsylvania School of Medicine

nachricht Similarities found in cancer initiation in kidney, liver, stomach, pancreas
21.02.2018 | Washington University School of Medicine

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Researchers invent tiny, light-powered wires to modulate brain's electrical signals

21.02.2018 | Life Sciences

The “Holy Grail” of peptide chemistry: Making peptide active agents available orally

21.02.2018 | Life Sciences

Atomic structure of ultrasound material not what anyone expected

21.02.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>