Yuze Sun

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.

This paper describes the design of a piezoelectric-driven hydraulically amplified Braille-flexible bump device that enables the flexible formation of Braille characters. A piezoelectric vibrator is used to excite fluid resonance in a cavity, and displacement is realized by compressing the fluid, allowing Braille character dots to be formed. First, the structural design and working principle of the device, as well as the method used to drive the fluid, are explained. Expressions for the output displacement and amplification ratio of the flexible film and piezoelectric vibrator are then obtained through kinetic analysis of the system unit. Subsequently, the structural parameters that affect the output displacement and the liquid amplification are described. Finally, experimental tests of the system are explained. The results indicate that the output displacement of the contact formed by the flexible film reaches 0.214 mm, satisfying the requirements of the touch sensitivity standard for the blind, when the fluid cavity diameter measures 31 mm and the resonance frequency is 375.4 Hz. The corresponding water discharge is 8.8 mL. This study proves that constructing a Braille bump device in this way is both feasible and effective.

With the popularization of integrated circuits, MEMS, and portable electronic devices, chemical batteries have many disadvantages as the main energy supply method, such as large size, high quality, and limited energy supply life, requiring regular replacement, resulting in waste of materials, environmental pollution, and other issues. From the above reasons, energy harvesting technology plays an important role in improving the efficiency and life of electronic equipment. In order to explore the influence of the bimorph piezoelectric vibrator’s structural parameters on the power generation capacity, this paper establishes a cantilever beam rectangular bimorph piezoelectric vibrator power generation model, derives the mathematical expression of the bimorph piezoelectric vibrator power generation, and determines the parameter factors that affect the power generation effect. Using MATLAB simulation analysis to obtain the influence relationship curve of system output voltage and structural parameters, the experiment tests the influence law of output voltage and thickness ratio, width‐to‐length ratio, and Young’s modulus ratio; the test results are consistent with the theoretical analysis, verifying the theory and the correctness of the analysis. The results show that when the thickness ratio is 0.58 and the width‐to‐length ratio is 1, the power generation effect of the piezoelectric vibrator is the best to reach 14.5V; the power generation capacity of the transducer is inversely proportional to Young’s modulus ratio. This research provides a new idea for the popularization of integrated circuits, MEMS, and portable electronic devices.