Beating Heart Cells Power Robotic Sea Animals

Scientists are studying propulsion in robotic jellyfish and stingrays made of living rat heart cells, and someday the same concepts could be used to build a human heart from scratch. These agents of biomimicry, called "medusoids," are made of heart cells because of their ability to contract and create movement. For now, scientists can guide their movement with laser light.

They are able to do so because heart cells contract in response to stimuli, and the rat heart cells in the jellyfish and stingray models are modified to contain a light-detecting protein so researchers can signal the cells to contract simply by flashing a light, making the medusoids "swim" just like a beating heart pumps blood throughout the body system.

"I'm looking at it and I'm trying to understand the heart," said Kevin Kit Parker, whose five years in robotics is largely inspired by his young daughter's fascination with aquariums.

Plus, the right and left wings can be programmed to respond to different wavelengths of light, fine-tuning the robots' movements to successfully navigate obstacle courses created by the scientists as a "biomimetic video game."

"The heart is a hollow muscle," said cardiovascular surgeon Simon Hoerstrup. "Many of the features you see in this ray, you find in the heart."