The Star Wars’ R2-D2 robot is passé. A research team headed by an engineer from the University of Houston (UH) developed a new type of soft robot, made of actuating electronics, ultrathin sensing, and temperature-sensitive artificial muscle capable of adapting to the surroundings and crawling, comparable to the movement of a caterpillar or inchworm.
Cunjiang Yu, Bill D. Cook Assistant Professor of mechanical engineering, noted that prospective applications include search and rescue during natural disasters, on the battleground, or surgery and rehabilitation. He further stated that since the robot body has the ability to change shape according to the environment, it can slip through narrow crevices to seek survivors in the debris left after a bombing or an earthquake.
“They sense the change in environment and adapt to slip through,” Yu said.
These soft robots, composed of ultrathin deformable sensors and actuators as well as soft artificial muscle, are highly advantageous compared to the conventional rigid robots used for automation and other physical tasks.
According to the researchers, their study, which was featured in the Advanced Materials journal, has been inspired by nature. “Many creatures, such as inchworms that have completely soft compliant bodies without any rigid components (e.g., bones), exhibit unprecedented abilities in adapting their shapes and morphologies and unique locomotion behaviors,” they described.
Conventional soft robots are not capable of adapting to their surroundings or moving autonomously.
The prototype adaptive soft robot consists of a liquid crystal elastomer, which is doped using carbon black nanoparticles in order to improve thermal conductivity, as the artificial muscle, in combination with silicon-based light sensors and ultrathin mesh-shaped stretchable thermal actuators. The heat to activate the robot is provided by the thermal actuators.
The prototype, having a length of only 28.6 mm or slightly more than an inch, is small-however, Yu said it can be easily enlarged. That is the subsequent step, together with experiments using different sensor types. He said that although the prototype employs heat-sensitive sensors, it can also be made with smart materials that are activated by light or other signals.
“This is the first of its kind,” Yu remarked. “You can use other sensors, depending on what you want it to do.”
Besides Yu, co-authors of the study include Chengjun Wang, Kyoseung Sim, and Zhoulyu Rao, all from UH; Hojin Kim and Rafael Verduzco from Rice University; Jin Chen from Beijing University; and Yuhang Li, Weiqui Chen, and Jizhou Song of Zhejiang University.
The National Science Foundation and the American Chemical Society Petroleum Research Fund Doctoral New Investigator Grant funded this study.
Researchers led by a University of Houston engineer have reported a new class of soft robot, composed of ultrathin sensing, actuating electronics and temperature-sensitive artificial muscle that can adapt to the environment and crawl, similar to the movement of an inchworm or caterpillar. (Credit: University of Houston)