An Electrothermally Actuated MEMS Braille Dot

Abstract

With some recent attempts on development of micro tactile displays, the realization of portable Braille is becoming more feasible. Such tactile displays can help visually impaired individuals to read and comprehend patterns by using the sense of touch. The current proposed designs for such tactile displays mainly use fluid expansion to enhance the out of plane displacements of the Braille dots. These methods render some challenge in terms of fabrication and size. In this work, we propose a design based on electrothermal actuation of a micro Braille dot. The ultimate goal of the research is to work towards a wearable system that can be connected to a computer for reading text files. The proposed design can generate out of plane displacements of 250 µm at a 58 ℃ rise from ambient. The dot can be actuated by low input voltage of 1.36 V and can apply a force of 5 mN. Physical displacement and temperature can reinforce a valid dot detection.