Stingray made out of heart cells
July 8, 2016

Team develops robotic stingray made out of heart cells

Using heart cells taken from a rat, scientists have developed a robotic stingray that can be controlled using pulses of light, according to a new report in the journal Science.

The study team told BBC News that their creation could provide valuable new insight into the function of the human heart.

"It turns out the musculature in the stingray has to do the same thing as the heart does: it has to move fluids," said study author Kevin Kit Parker, a bioengineering professor at Harvard University.

Creating an artificial stingray

The researchers said they built the aquatic robotic animal to learn how a natural ray slides through its liquid environment. Their prototype, weighing 10 grams and measuring just over half an inch long, was made with a gold skeleton and a layer of 200,000 cardiac cells covered with a gel-like material similar to the gel put to use in breast implants.

The team genetically modified the cardiac cells to make them responsive to light.

"When we have a light in the front (of the ray), we activate an electrical signal in the tissue and it propagates like a wave through the musculature," Parker said. "You get this undulatory motion of the fins, and it looks as if it is chasing the light."

Each side of the robot includes different cardiac cells responsive to particular light wavelengths. When used one wavelength or another, the researchers could steer the robot in a selected direction. Applying this guidance system, the artificial ray was capable of completing a simple obstacle course.

Scientists said they hope the ray will help in learning more about cardiac physiology.

"We are making assumptions from our physiology textbooks that a heart beats the same way from every beat," Parker told the BBC World Service program Science in Action. "But if you talk to cardiovascular surgeons, they would tell no, it always beats differently."

Because the robot has a soft body, it is one of the first of its kind compared to technologies that use rigid frames founded on the stride of insects or mammals. A different "soft robot" is an artificial jellyfish, currently being developed by the same Harvard laboratory.

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Image credit: Harvard