Swimming Stingray Robot: Rat heart muscle was used to create this adorable robotic stingray. It’s as outlandish as it sounds, yes. “We used a small amount of rat cardiac cells, a small amount of breast implant, and a small amount of gold to make this device. Except for genetic engineering, that’s essentially it “Kit Parker, the Harvard bio-engineer who oversaw the development of the robot, says this.
To move ahead, the tissue-engineered ray’s fins undulated in response to visual stimulation. Parker’s robotic stingray is a teeny-tiny 10 grams in size and weighs less than half an inch. Instead of swimming like a stingray or a skate, it uses the same undulating action. There are 200,000 genetically modified cardiac muscle cells developed on the bot’s underbelly to fuel its movement. Even more bizarre, Parker’s team created the robot to follow brilliant pulses of light, allowing it to effortlessly twist and turn through obstacle courses. Today, Science published an article on a new and intriguing robot.
Adam Feinberg, a roboticist at Carnegie Mellon University who has worked with Parker’s team before but was not involved in designing this new robot, believes that “by employing live cells they were able to create this robot in a way that you really couldn’t reproduce with any other material,” he said. “Muscles begin to swim when a light is shined on them. Electronics and actuators on board would be unable to duplicate this movement while maintaining the vehicle’s portability and small weight. Like television, it has a remote control.”
Getting Started with a Living Bot
Let’s peel back the layers of this bad boy to see how rat muscles can power a robot stingray. The stingray robot has four layers of material. The top layer is a silicone 3D body cast in a titanium mold, which Parker describes as “the same thing as the outer covering of a breast implant.” The rest of the components are held in place by this spherical, slender structure.
The gold skeleton is the second layer down. In order for the pectoral fins to return to their original locations once they have finished undulating, Parker explains that the skeleton is present. What is the appeal of gold? According to his assessment, the material was “very simple to work with” due to its perfect combination of rigidity and elasticity.
It’s the third layer of ultra-thin silicone, this time on the bottom. However, it also serves a major function in preventing direct contact between the heart muscle and the gold. For the rat cells to “develop with the exact muscle architecture we desire,“ Parker adds, it is necessary to cast the silicone with precisely the proper small-scale patterns in addition to the top 3D layer. With the correct geometric design, we may direct these cells to build the tissue that we desire. “
Last but not least, a layer of live rat cells covers the robot’s underbelly. Originally from the heart muscle, these cells have been genetically modified and are now being used to treat cancer. In a serpentine, back-and-forth motion, Parker applies them to each of the robot stingray’s two fins. To mimic the undulating motion of genuine stingrays, these cells convey signals to other cells down the line, which in turn causes a chain reaction of muscular flexing.
This is where genetic engineering comes into play. Muscles in the robot-stingray will only contract if they are exposed to a certain wavelength of intense light. Optogenetics, a form of genetic engineering, makes it possible for normally functioning cells to respond to light. For Parker’s stingray to follow, he uses a simple two-pronged light source. When the lights go off, the robot begins to jerk its arms and legs in the air. Parker simply has to use a stronger or more rapidly flashing light on one side of the stingray to get it to bank and turn. Increasing the speed and/or force with which the fins move is a result of both of these factors.
The rat heart cells may be nourished and kept alive by the bot’s ability to float in a liquid that contains suspended nutrients. Even after six weeks, the stingray bot was still swimming with more than 80% of its cells still functioning. Feinberg, on the other hand, acknowledges that there are obstacles to be overcome. Because the cells are so vulnerable to infection, even with the correct nutrition, you would not be able to swim this bot outside of a laboratory. It’s not protected from germs or fungi because it lacks an immune system, Feinberg adds. Researchers say they used rat cardiac cells, breast implants, and gold to make the device. “We built this thing with a pinch of gold.”
Is it a machine or is it a living organism?
Parker’s robot, which he says is alive since it is made of animal cells, raises an interesting philosophical question: “It’s not a machine, but rather a biological living form,” he concludes. Because it cannot breed, I wouldn’t call it an organism, but it is unquestionably alive.”
That diverse scientists can gain so much insight from the stingray bot is one of its most intriguing features. According to Parker, the most important lesson he learned from the robot is that it shows how a certain type of heart muscle can flush and circulate liquid around it. Marine biologists can study at ray muscle tissues to determine why they are arranged the way they are, while roboticists and engineers find alternative methods to employ living cells as building materials.
In addition, Parker was kind enough to answer my readers’ questions. What do they need to take with them from this experience? “Stingrays were made from of rats. The only thing kids need to know is that this is the best thing they’ll see all year long.”