Engineer Ren Hao Soon was watching YouTube one night when he first learned about the pangolin—a scaly mammal that can curl up into a ball. The animal’s armor inspired him to design a tiny robot that can perform medical tasks inside the body.

With his research team at the Max Planck Institute in Germany, Soon created a flexible rectangle covered with metal scales. Using magnets, the scientists can trigger the robot to curl up so it can hold medicine. They can then direct the bot to roll to specific locations, like the digestive tract, to deliver the medicine. This miniature robot “is a very good example of how we can learn from nature,” says Soon.