Back in April, we introduced soft robotics on the blog and showed how the future of man-made robots would need to be gentler to exist side by side with human beings. Today, a new generation of robots have been created at the University of Illinois, and while they may be flexible, they’ve got some muscle to back them up. Literally.
Engineers at the University of Illinois at Urbana-Champaign demonstrated a class of walking “bio-bots,” which are powered by a strip of skeletal muscle cells and can be triggered by an electric pulse. This gives researchers a simple way to control the bio-bots and opens the possibilities for other forward design principles, allowing engineers to customize these bio-bots for specific applications.
“Biological actuation driven by cells is a fundamental need for any kind of biological machine you want to build,” said study leader Rashid Bashir, Abel Bliss Professor and head of bioengineering at the University of Illinois, to the Illinois New Bureau. “Biology is tremendously powerful, and if we can somehow learn to harness its advantages for useful applications, it could bring about a lot of great things.”
Bashir and his group, who were published in the online edition of Proceedings of the National Academy of Science, have been pioneers in designing and building bio-bots. The bots are less than a centimeter in size and made of flexible 3-D printed hydrogels and living cells. Originally, the group used heart cells to cause the bot to “walk,” but that design proved difficult to work with. Since heart cells constantly contract, it denied the researchers any control over the bot’s motion.
The group then switched to skeletal muscles, giving them more control over the bots’ movements. “Skeletal muscles cells are very attractive because you can pace them using external signals,” Bashir said. “For example, you would use skeletal muscle when designing a device that you wanted to start functioning when it senses a chemical or when it received a certain signal.” Check out this video of the bio-bots in action!
The bio-bots are designed after the muscle-tendon-bone complex found in nature. There is a backbone of 3-D printed hydrogel, strong enough to give the bio-bot structure but flexible enough to bend like a joint. Two posts serve to anchor a strip of muscle to the backbone, like tendons attach muscle to bone, but the posts also act as feet for the bio-bot.
This idea of ‘building with biology’ is not a new one. Researchers have already been working diligently on projects to reverse engineer living tissues and organs and come up with new robots to help deliver drugs to the human body. Even 3D printing has led to breakthroughs in the medical field, and we feel this is only the beginning of a bioengineering renaissance.
“The idea of doing forward engineering with these cell-based structures is very exciting,” says Bashir. “Our goal is for these devices to be used as autonomous sensors. We want it to sense a specific chemical and move towards it, then release agents to neutralize the toxin, for example. Being in control of the actuation is a big step forward toward that goal.”
Photo credit: Janet Sinn-Hanlon, Design Group@VetMed via Illinois News Bureau