The technology that makes a cell phone vibrate is the same technology that provides more natural movements to prosthetic limbs.
A University of Houston research team is working on recreating and enhancing this technological effect, which, if successful, could result in better prosthetic movements and also provide instant electrical power for soldiers and others through the simple act of walking.
Pradeep Sharma, a UH mechanical engineering professor, is leading the team to create a “piezoelectric on steroids.” Piezoelectricity is the ability of some materials to generate an electric charge when placed under stress. This pioneering technology already is more useful than many people realize. Piezoelectrics are involved in everything from making an airbag deploy to how a lighter produces a flame.
Although piezoelectrics are naturally occurring, they have their limits. If an application requires a level of energy conversion not found in a naturally occurring piezoelectric, a composite consisting of piezoelectrics and non-piezoelectrics must be made. Sharma and his team are creating piezoelectrics from man-made materials that have no piezoelectric property.
“If you press on a piezoelectric, or apply mechanical force, it will produce a voltage,” Sharma said. “Or, if you apply a voltage or electrical force to it, the object will bend or change its shape.”
An engineered piezoelectric strip placed in the boot of a soldier would generate electricity and power the increasing number of devices that soldiers carry. The walking motion produces force or deformation of the strip, which generates electricity with every step. The highly customizable piezoelectrics also could enable the creation of prosthetics that come closer to offering both the flexibility and the strength of real limbs. Current prosthetic limbs face challenges in range and movement by the two types of naturally occurring piezoelectrics, ceramic and polymer.
“Ceramic piezoelectrics are very hard and brittle, and don’t allow for a lot of movement,” Sharma said. “They take a lot of electrical energy for a lot of motion. Polymers are better for large forces of motion, but don’t have a lot of strength. So, you can stretch adequately, but may not even be able to pick up an egg. Nature has given us some elements, and now we’re going beyond and designing materials from the ground up. We wanted to combine the best qualities of the two types of piezoelectrics, among other things.”
Sharma has been working to refine his theoretical ideas for two years. His research team includes Ramanan Krishnamoorti of the UH Cullen College of Engineering, Boris Yakobson of Rice University and Zoubeida Ounaies of Texas A&M University. Krishanmoorit and Ounaies will begin putting the research to the test with the help of a $1.22 million grant from the National Science Foundation.
“The real applications of this technology are going to come from the fact that you don’t have to depend on existing piezoelectrics,” Sharma said. “You can create materials, using certain nanoscale effects, that give higher energy conversion. These are basically piezoelectrics on steroids.”
Scientists create biodegradable, paper-based biobatteries
08.08.2018 | Binghamton University
Ricocheting radio waves monitor the tiniest movements in a room
07.08.2018 | Duke University
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.
Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
14.08.2018 | Life Sciences
14.08.2018 | Life Sciences
14.08.2018 | Earth Sciences