Design and experimental study of piezoelectric driven flexible Braille contacts

A new flexible contact structure using the principle of air pressure amplification is proposed to enable better access to information for the blind. First, the structure and working principle of piezoelectric flexible Braille contacts were designed and analyzed, and the theoretical model of air pressure amplification and theoretical expressions were established. Then the gas–solid coupling simulation analysis was carried out using COMSOL Multiphysics software to derive the influencing factors of the system flexible contact amplification and the degree of influence of different gases on the contact output displacement, and the structure of flexible Braille contacts was tested experimentally. The experimental results show that when the diameter of the air cavity is 24 mm, the height of the cavity is 6 mm, the thickness of the flexible film is 0.1 mm, the contact height is 2 mm, the input voltage is 135 V, the resonance frequency reaches 196.5 Hz, the maximum output displacement of the piezoelectric flexible Braille contact is 0.286 mm, and the point display effect of the Braille contact is more significant, which verifies the feasibility of the device.