Scientists have found a way to make'soft robots' using balloons that change shape when inflated with air. This new technology has been used to create a robot with a gripping hand, a flapping fish tail, and a moving coil that can be used to retrieve a ball. In contrast to conventional rigid robots, these soft robots are "naturally geared to interact with the soft stuff, like humans or tomatoes", assistant professor of chemical and biological engineering at Pierre-Thomas Brun at Princeton says. This could make them significantly more useful for harvesting food, taking items off a conveyor belt, or providing health care – as part of wearable exosuits or under-the-skin devices that could help people with heart issues. The robots are built by injecting bubbles into a liquid polymer called elastomer which becomes rubbery when it solidifies, then inflating the device to make it bend and move.