Comment Can't see?, you can feel the fingers... (Score 2, Informative) 135
In the early 90's I worked with the robotic finger spelling hands called "Dexter" & "Ralph". Those devices were intended for individuals who are both deaf and blind. An individual with this kind of disability must rest their hand on the back of someone's hand (or on the back of the robotic hand) and feel letters as they are signed by the hand/fingers.