Researchers at the University of California Los Angeles bioengineering department developed a tissue-based soft robot that resembles a stingray. The research is being used to transform regenerative medicine, as well as diagnostics and robotic systems that could function within the human body.
The classical image of a robot remains more or less the reality of today’s autonomous machines. Stiff, metallic and limited to a few set movements, most robots yet to reach the point of natural, flowing movement that accurately mimic the natural world. Thanks to modern Artificial Intelligence and machine learning, they can now behave more human than ever, but they still look and feel like the hardware that they are.
That is changing, though, as more researchers develop soft robots that mimic the biomechanics of an actual animal or organism.
In one of the latest cases, professor Ali Khademhosseini and his team of researchers at the University of California Los Angeles bioengineering department have developed a tissue-based soft robot that resembles a tiny stingray. The work could lead to advances in regenerative medicine, as well as diagnostics and robotic systems that could eventually function within the human body.
“Right now, most of what people think about robotics is just hardware and electronics, but more and more people are trying to see how they can be improved,” Dr. Khademhosseini says, “Things like being able to add tactile feedback or being able to have additional sensing capabilities. Being able to have the kind of features that biological systems have evolved to do.”
Read More about the latest in regenerative medicine from AABME.org.
Soft robotics brings together the cognitive power of modern robots with parts that are more pliable and resemble things found in the natural world. The goal, in part, is to create robots that are easier to interact with and integrate into practical applications.
“Soft robots are typically made from pliable parts, like soft plastic and things like that, integrated with electronic systems,” says Khademhosseini. “But the evolution of them is about making these things even smarter, and having more logical components where each cell could potentially be able to perform many different functions. It just adds additional capabilities to what one can do now.”
The flat, elongated stingray design of the 10-millimeter long UCLA robot proved to be a simple way for the team to demonstrate the movement and flexibility capabilities of its technology, modeling the biomechanical features of the fish. Starting with a 3D-printed skeleton, the team layered the robot with a series of live heart cells and flexible electrodes. Taking advantage of the natural directional flex in the tissue — heart tissue is generally omnidirectional, moving in one set direction and contracting when activated — they used the electrodes to activate certain cells at certain times, effectively controlling the movement of the robot.
The skeleton is printed in a way that allows some asymmetry in its mechanical properties; in some directions it is stiffer and more difficult to move than in other directions. When the heart cells were layered on top and started growing into artificial muscles their movements were coordinated through each layer of the robot.
“When we decided on the manta design we started to think about what the characteristic of the animal are,” says Bianca Migliori, a Ph.D. student in neurobiology, currently at Columbia University, who worked on the project with Dr. Khademhosseini and coauthored the final report. “It has a backbone, but it’s pretty soft and can flaps its wings, so it also has some axons to propagate that stimuli. We needed something to provide electricity from inside the material itself, so we decided to use gold and we designed this very flexible, electrode which could allow for movement of the membrane while still help the electrical propagation to occur within the animal.”
Broad applications
As interesting as the robot itself is to watch in action, it’s the potential applications of this technology that really has researchers excited.
Soft robots can be used as sensors, since they can sense their surrounding environments. Engineered tissues like these can also be leveraged to develop artificial meats that grow like biological tissues. The potential is to actually make living machines that can be programmed to do different sorts of work than they naturally would.
The technology can also be used to develop personalized cardiac patches. If a patient has broken tissue within their heart, soft robotics can help to reconstruct it and give shape and function to the tissue. The cell could be designed not to just beat, but to give doctors full control of the function and directionality of the impacted cells, allowing them to design perfect replicas for each patient.
The electrode technology used in the stingray robot could also forge a new path for pacemakers, Migliori says.
“Right now, pacemakers are just tape things that are inserted into the heart,” she says. “But what if you could expand the tape and integrate it totally into the cardiac tissue. It would something very small and tuneable to every heart.”
This type of functionality could extend throughout the body to include nearly any type of tissue that physicians want to engineer. The potential to replace cells, organs, and body parts is there. Medical devices could eventually be engineered to include both biological and engineered components, with both sides able to communicate and interact with each other.
“We're still very far away from these kind of sci-fi, cyborg-like concepts, but I think for many different applications there are things that biological systems do well, and there are things that current engineered systems that humans have developed do well,” Khademhosseini says. “The integration of them is an interesting opportunity. Biology has for billions of years been evolving these cells to do some pretty incredible things. Now we’re starting to think about how we can use that idea for different applications.”
Learn More about new robotics technologies on AABME.org.