The Research Of Electromagnetic Braille Display Device

In today’s world, there has approximately285million vision-impaired people, which about39million blinds. In this paper, It has innovatively proposed a portable Braille display device,which could deal with some issues, such as large reading needs and reading difficulties of theblind. It could show dynamic Brailles to replace traditional paper books or electronic textdocument, in order to replace the bulky traditional Braille books with Braille e-books. Blindstouch dynamic braille to read text via fingertip. It has information storage capacity, fast response,low cost, small size and easy to carry, which could satisfy the needs of blind readers. It isessential aid for the Blind to learn Braille.The main content of the article is to design the mechanical structure of braille displaydevice, and to improve structure for the problems existing in the design of braille display device,and finally to test performance of the braille display device comparing with the originalstructure.Firstly, this paper has elaborated background and significance of all Braille display devices,which has reviewed their research process, which has compared with their implementations andperformance. In particular, there are some difficulties in the research and development of theBraille display device. They include the way of Braille contact drive, Braille contact control, theresolution of the Braille contact and so on. What’s more, this paper has identified research goalsand contents.Secondly, The paper puts forward to reasonable design scheme according to the existingbraille display device, whose Braille contacts used electromagnetic drive mode. According to thepersons’ fingers touch threshold and the braille contacts’highlight height, the driving mechanismwas designed to meet the requirements of blinds. According to braille contacts drivingmechanism, the author has designed the overall mechanical structure of the braille display andcompleted a three-dimensional modeling of all parts. The paper has put forward feasibleprocessing methods and manufactured the first-generation prototype.Thirdly, the internal structure of the braille-contact driving mechanism of the prototype wasdetailed and the driving mechanism of power supply was determined.According to magnetic field distribution of the DC solenoid, it has worked out the magneticfield intensity of the electric solenoid and the electromagnetic force of the coil produce.According to pressure valve of human fingertip，we has figured out the force the contact applieson the fingertip so that we can solve the electromagnetic force generated by the drive mechanism. Also we can derive the current and the voltage in the field coil according to electromagneticforce the driving mechanism exports.Then, we have analyzed the characteristics of the magnet and magnetic circuit in the drivemechanism and understood the factors affecting the electromagnet suction. Aiming at theexisting problems in the first generation prototype, we has conducted the secondaryimprovements of braille display mechanism combining with the factors affecting theelectromagnetic force, and tested the performance of the improved driving mechanism. The testresults showed that the secondary drive mechanism could improve the output capacity of theelectromagnetic force.Finally we summarized the full text, speculated future work of braille display device.