Our muscles work in harmony, twitching and pulling fibers in perfect coordination. While some align in straight lines for predictable movements, others form complex patterns, enabling flexibility in all directions. Inspired by this intricacy, scientists create artificial muscles that mimic these dynamic patterns for futuristic biohybrid robots.
But here’s the catch: until recently, artificial muscles could only pull in one direction, limiting robotic motion.
MIT engineers have made a breakthrough in this area—they’ve developed a method to grow muscle tissue that contracts in multiple directions.
Their inspiration? The human iris is the part of our eye that adjusts the pupil’s size by contracting concentrically and radially.
Here’s how they did it:
The team created a handheld “stamp” using 3D printing. Its microscopic grooves, as small as a single cell, were pressed into a soft, jelly-like hydrogel. Muscle cells were seeded into these grooves, aligning and growing into functional fibers.
These engineered muscle fibers mimicked the iris, forming patterns that allowed contraction in different directions. When stimulated with light pulses, the artificial iris contracted just like its natural counterpart!
This breakthrough offers more than just cool science. These multidirectional muscles could power soft robots capable of navigating underwater or squeezing through tight spaces—places traditional machines simply can’t go. And because these robots are made from biological tissues, they’d be biodegradable and energy-efficient, paving the way for sustainable solutions.
Ritu Raman, leading the research at MIT, emphasizes the potential of their new technique: “We hope to build biohybrid robots that are not only more capable but also environmentally friendly.”
New microscopic biohybrid robots propelled by muscles, nerves
The possibilities are endless, from helping in medical applications like restoring muscle function to creating fish-like swimming robots. This achievement showcases how precision techniques and biology can join forces to redefine what machines can do.
Imagine revolutionizing robotics by taking inspiration from a Jell-O mold. That’s exactly what a team at MIT did!
They designed a tiny stamp with grooves as small as a single cell to guide muscle cells into forming complex patterns. Think of it like giving the cells a roadmap to grow along.
The team pressed the stamp into a squishy, jelly-like hydrogel—far softer than Jell-O. This wasn’t easy; they had to coat the stamp with proteins to ensure it imprinted smoothly and didn’t tear the fragile gel. Once the grooves were in place, muscle cells were added, and the magic began. Within a day, the cells aligned along the grooves and fused into fibers, creating a structure modeled after the human iris.
The results were mind-blowing. When stimulated with light pulses, the artificial iris contracts in multiple directions—just like the muscles in your eye that adjust your pupil size.
While the real human iris uses smooth muscle tissue, the team demonstrated using skeletal muscle cells, showing the potential of their stamping technique to create muscles that move in complex, coordinated ways.
And here’s the kicker: this stamp method isn’t limited to muscle cells. It could grow other types of biological tissues, like heart cells or neurons. Plus, the stamp can be created with a regular tabletop 3D printer, making it accessible and innovative.
The goal? To build soft, biohybrid robots capable of navigating tight spaces, swimming gracefully, or even breaking down naturally when their job is done—completely sustainable and energy-efficient. Talk about blending biology and tech into the future!
Journal Reference:
- Tamara Rossy, Laura Schwendeman, Sonika Kohli et al. Leveraging microtopography to pattern multi-oriented muscle actuators†. Biomaterials Science. DOI: 10.1039/D4BM01636J
Source: Tech Explorist
