Refreshable Braille Gets An Engineer's Touch

KATIE CAGEN '14, FINALIST IN NATIONAL COLLEGIATE INVENTORS COMPETITION, WORKS TO ADVANCE ACCESSIBLE TECHNOLOGIES

When Katherine (Katie) Cagen '14 was applying to Harvard, she made a new friend on campus who happened to be visually impaired. "I saw how much she used technology to be able to access her course materials," says Cagen. "Spending time with Sally made me realize that there's this whole other world out there of adaptive technology."

For her capstone design project at the Harvard School of Engineering and Applied Sciences (SEAS), Cagen invented a device she calls Ferrotouch. It is a tactile display technology that uses electromagnetically actuated materials to create a sort of "refreshable Braille."

Actually, refreshable Braille machines already exist; they use pins to display a changing message. But they cost so much, Cagen quips, "a Tweet would cost you about sixteen grand." Instead, having taken a course on applied electromagnetics, she fabricated her own electromagnets and arranged them underneath a layer of ferrofluid, a colloidal suspension of iron nanoparticles. Under the magnets' influence, the ferrofluid forms bumps that the user can feel through a layer of elastic...