Kate Darling places a dinosaur robot the size of a housecat on the table, and flips the power switch on its belly. The dinosaur, which Darling calls Mr. Spaghetti, purrs to life. He lifts his little green head and closes his blue eyes affectionately as she rubs his neck. “He has touch sensors in his head and on his back,” she explains. “They develop their own personalities depending on how you treat them.”