Smart materials that change their properties or behaviors in response to environmental factors such as temperature are often referred to as “smart” or “responsive” materials. These materials’ physical or chemical properties can change in response to external stimuli.
Researchers claim to have created a new composite material that can change its behavior depending on temperature in order to perform specific tasks. These materials are destined to be used in the next generation of self-driving robots that interact with their surroundings.
The new study, led by University of Illinois Urbana-Champaign civil and environmental engineering professor Shelly Zhang and graduate student Weichen Li, and conducted in collaboration with University of Houston professor Tian Chen and graduate student Yue Wang, uses computer algorithms, two distinct polymers, and 3D printing to reverse engineer a material that expands and contracts in response to temperature change with or without human intervention.
The findings of the study have been published in the journal Science Advances.
Our study demonstrates that it is possible to engineer a material with intelligent temperature sensing capabilities, and we envision this being very useful in robotics. For example, if a robot’s carrying capacity needs to change when the temperature changes, the material will ‘know’ to adapt its physical behavior to stop or perform a different task.
Shelly Zhang
“Creating a material or device that will respond in specific ways depending on its environment is very challenging to conceptualize using human intuition alone — there are just so many design possibilities out there,” says Zhang. “So, instead, we decided to work with a computer algorithm to help us determine the best combination of materials and geometry.”
The team first used computer modeling to conceptualize a two-polymer composite that can behave differently depending on user input or autonomous sensing at different temperatures.
“For this study, we developed a material that can behave like soft rubber in low temperatures and as a stiff plastic in high temperatures,” Zhang went on to say.
Once fabricated into a tangible device, the team tested the new composite material’s ability to respond to temperature changes to perform a simple task — switch on LED lights.
“Our study demonstrates that it is possible to engineer a material with intelligent temperature sensing capabilities, and we envision this being very useful in robotics,” Zhang said. “For example, if a robot’s carrying capacity needs to change when the temperature changes, the material will ‘know’ to adapt its physical behavior to stop or perform a different task.”
One of the study’s defining features, according to Zhang, is the optimization process, which allows researchers to interpolate the distribution and geometries of the two different polymer materials required.
“Our next goal is to use this technique to add another level of complexity to a material’s programmed or autonomous behavior, such as the ability to sense the velocity of some sort of impact from another object,” she went on to say. “This will be critical for robotics materials to know how to respond to various hazards in the field.”
