Each year, soft robots gain new abilities. They can jump, squirm, and grip. Unlike hard robots, they can handle tomatoes without bruising the fruit, resurface unscathed after being run over by a car, and journey through radiation, disaster zones, and outer-space with few scars. Now, a new invention gives soft robots the ability to roll, undulate, sort, meter liquids, and swallow. Customizable designs could find use in labs, hospitals, and even inside the h..