Abstract:
At present, traditional Braille books have had difficulty meeting the needs of the blind, this paper proposes a new type of ultrasonic resonant Braille display cell based on the squeeze film generated by ultrasonic vibration. The Reynolds equation which de? termines the aerodynamic characteristics of the squeeze film is derived theoretically, the mechanical model and approximate solu? tion of the output buoyancy are obtained by using the “piston effect” of the squeeze film, the vibration characteristics and output performance test of Braille display cell were tested using the built experimental platform. The results show that the resonant fre? quency of the Braille display cell is 30.8 kHz, when the peak-to-peak value of the excitation voltage is 130 Vpp to 200 Vpp, a sta? ble squeeze film with certain buoyancy can be formed. The theoretical calculation results are basically consistent with the experi? mental results. In the experiment, three kinds of samples can be lifted from 13.92 μm to 47.71 μm, Braille display cell has suffi? cient output performance.