Soft materials are great at damping energy — that’s why rubber tires are so good at absorbing the shock of bumps and potholes. But if researchers are going to build autonomous soft systems, like soft robots, they’ll need a way to transmit energy through soft materials.
Now, researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS), in collaboration with colleagues at the California Institute of Technology, have developed a way to send mechanical signals through soft materials.
The research is described in the Proceedings of the National Academy of Sciences.
“Soft autonomous systems have received a lot of attention because, just like the human body or other biological systems, they can be adaptive and perform delicate movements. However, the highly dissipative nature of soft materials limits or altogether prevents certain functions,” said Jordan Raney, postdoctoral fellow at SEAS and first author of the paper. “By storing energy in the architecture itself we can make up for the energy losses due to dissipation, allowing the propagation of mechanical signals across long distances.”
The system uses the centuries-old concept of bistable beams — structures stable in two distinct state — to store and release elastic energy along the path of a wave. The system consists of a chain of bistable elastomeric beams connected by elastomeric linear springs. When those beams are deformed, they snap and store energy in the form of elastic deformation. As the signal moves down the elastomer, it snaps the beams back into place, releasing the stored energy and sending the signal downstream like a line of dominos. The bistable system prevents the signal from dissipating downstream.
“This design solves two fundamental problems in transmitting information through materials,” said Katia Bertoldi, the John L. Loeb Associate Professor of the Natural Sciences at SEAS and senior author of the paper. “It not only overcomes dissipation, but it also eliminates dispersive effects, so that the signal propagates without distortion. As such, we maintain signal strength and clarity from start to end.”
The beam geometry requires precise fabrication techniques. If the angle or thickness of one beam is off by one degree or millimeter, the whole system fails.
The team used advanced 3D printing techniques to fabricate the system.
“We’re developing new materials and printing methods that enable the fabrication of soft materials with programmable bistable elements,” said Jennifer A. Lewis, the Hansjorg Wyss Professor of Biologically Inspired Engineering and coauthor of the paper.
The team designed and printed a soft logic gate using this system. The gate, which looks like a tuning fork, can be controlled to act as either as an AND or as an OR gate.
“It’s amazing what you can do using simple beams — a building block that’s been around hundreds of years,” said Bertoldi. “You can do new stuff with a very old, well studied and very simple component.”
Learn more: Transmitting energy in soft materials
The Latest on: Autonomous soft systems
via Google News
The Latest on: Autonomous soft systems
- Austin Bay: China prepares for ‘informationized’ waron November 28, 2020 at 9:10 pm
For at least two decades, Chinese military leaders have debated the idea that electronic information equipment has become the primary warfighting platform — not tanks, missiles or ships but the ...
- Fiat 500 3+1 electric vehicle gets a fresh redesignon November 26, 2020 at 8:41 am
Italian car manufacturing company Fiat has unveiled redesigns for its FIat 500 3+1 La Prima electric car, adding an extra door and sustainable materials.
- China Prepares for 'Informationized' Waron November 25, 2020 at 8:01 pm
Chinese Premier Wen Jiabao, speaking to the National People's Congress, declared that the Chinese military's most important mission was "to win local wars under Information Age conditions."Wen's ...
- On Point: China Prepares for 'Informationized' Waron November 25, 2020 at 5:48 pm
However, military analysts pointed out that Wen specified a violent (kinetic) action somewhere near China that must be won. Information Age warfare required integrated electronics and weapons hardware ...
- Fearing Abandonment, Hong Kong Activists Look to Biden Amid China Crackdownon November 20, 2020 at 12:46 am
Hong Kong's pro-democracy camp found an ally in President Donald Trump. The transition of power has left some concerned about continued American support against China.
- Robotics and Medicineon November 12, 2020 at 4:00 pm
Read our COVID-19 research and news. Brad Nelson, Editorial Board ETH Zurich, Switzerland The impact of robotics on medicine is undeniable. The success of Intuitive Surgical’s Da Vinci system ...
- Biobots are hybrid machines that have muscles and nerveson November 12, 2020 at 4:00 pm
An artist rendering of a new generation of biobots developed by researchers at the University of Illinois--soft robotic devices powered by ... researchers a step closer toward the development of ...
- Teaching the internet of things to learnon November 12, 2020 at 7:49 am
Autonomous vehicles and devices for intelligent homes are becoming increasingly complex. A new system based on machine learning is being designed to make the soft- and hardware used for these ...
- Self-driving air taxis could fly commuters in a post-pandemic worldon November 5, 2020 at 8:08 am
Andrea Ponti released a gallery of concept designs for a private jet-like drone that carries up to four passengers while they sit in single seats with soft fabric and leather cushions.
- 2020 Audi S6on June 5, 2020 at 11:34 am
a semi-autonomous driving mode, a head-up display, upgraded headlamps with automatic high-beams, soft close doors, a power trunklid, heated rear seats, a leather-wrapped dashboard, and a cabin ...
via Bing News